WO2013084880A1 - Surface light source device, light control device and display device using same, and illumination device - Google Patents

Surface light source device, light control device and display device using same, and illumination device Download PDF

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Publication number
WO2013084880A1
WO2013084880A1 PCT/JP2012/081373 JP2012081373W WO2013084880A1 WO 2013084880 A1 WO2013084880 A1 WO 2013084880A1 JP 2012081373 W JP2012081373 W JP 2012081373W WO 2013084880 A1 WO2013084880 A1 WO 2013084880A1
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WO
WIPO (PCT)
Prior art keywords
light
light source
source unit
light guide
emitted
Prior art date
Application number
PCT/JP2012/081373
Other languages
French (fr)
Japanese (ja)
Inventor
大祐 篠崎
豪 鎌田
昇平 勝田
昌洋 ▲辻▼本
Original Assignee
シャープ株式会社
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from JP2011266172A external-priority patent/JP2015038811A/en
Priority claimed from JP2011281478A external-priority patent/JP2015038814A/en
Application filed by シャープ株式会社 filed Critical シャープ株式会社
Publication of WO2013084880A1 publication Critical patent/WO2013084880A1/en

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    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
    • G02B6/0001—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings specially adapted for lighting devices or systems
    • G02B6/0011—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings specially adapted for lighting devices or systems the light guides being planar or of plate-like form
    • G02B6/0013—Means for improving the coupling-in of light from the light source into the light guide
    • G02B6/0023—Means for improving the coupling-in of light from the light source into the light guide provided by one optical element, or plurality thereof, placed between the light guide and the light source, or around the light source
    • G02B6/0031—Reflecting element, sheet or layer
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
    • G02B6/0001—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings specially adapted for lighting devices or systems
    • G02B6/0011—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings specially adapted for lighting devices or systems the light guides being planar or of plate-like form
    • G02B6/0066—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings specially adapted for lighting devices or systems the light guides being planar or of plate-like form characterised by the light source being coupled to the light guide
    • G02B6/0068—Arrangements of plural sources, e.g. multi-colour light sources
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
    • G02B6/0001—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings specially adapted for lighting devices or systems
    • G02B6/0011—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings specially adapted for lighting devices or systems the light guides being planar or of plate-like form
    • G02B6/0066—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings specially adapted for lighting devices or systems the light guides being planar or of plate-like form characterised by the light source being coupled to the light guide
    • G02B6/0073—Light emitting diode [LED]

Definitions

  • the present invention relates to a surface light source device, a light control device, a display device using the same, and an illumination device.
  • This application claims priority based on Japanese Patent Application No. 2011-266172 filed in Japan on December 5, 2011 and Japanese Patent Application No. 2011-281478 filed in Japan on December 22, 2011. The contents are incorporated here.
  • a transmissive liquid crystal display device that performs display using light emitted from a surface light source device.
  • This type of liquid crystal display device has a liquid crystal panel and a surface light source device disposed on the back side of the liquid crystal panel.
  • a conventional surface light source device includes a light source such as a light emitting diode (hereinafter abbreviated as LED) and a light guide plate.
  • LED light emitting diode
  • the light emitted from the light source is propagated inside the light guide plate and emitted from the entire surface of the light guide plate.
  • the surface light source device provided on the back side of the display panel may be referred to as a backlight.
  • Patent Documents 1 to 3 Surface light source devices for obtaining emitted light with different directivities have been proposed (see Patent Documents 1 to 3 below).
  • a lighting device for obtaining outgoing light having different directivity characteristics a first lighting device that makes light from a light source incident from the side of a light guide and emits light having directivity from one main surface of the light guide
  • a lighting device having a two-layer structure in which a light from a light source is incident on a diffusing member and a second lighting device that emits a diffused light beam is laminated see, for example, Patent Document 1).
  • the first illumination device is an edge light type illumination device for obtaining highly directional emitted light
  • the second illumination device is a direct illumination device for obtaining diffused light.
  • Patent Document 1 discloses an illumination device in which a first illumination device and a second illumination device having different directivities of emitted light are stacked in the thickness direction of a light guide plate.
  • a light guide plate including a plurality of prisms arranged concentrically, a first light source arranged at the center of the concentric circle of the light guide plate, and a position off the center of the concentric circle of the light guide plate.
  • An illumination device including a second light source arranged is disclosed.
  • Patent Document 3 a light guide plate, a first light source that makes light incident on the first end surface of the light guide plate, and a second light that makes light incident on a second end surface adjacent to the first end surface of the light guide plate are disclosed.
  • a characteristic adjusting unit for adjusting directivity of emitted light is provided on the light guide plate corresponding to each light source.
  • JP 2008-300206 A Japanese Patent No. 4274921 JP 2008-269865 A
  • the lighting device of Patent Document 1 Since the lighting device of Patent Document 1 has a configuration in which two sets of lighting devices, a first lighting device and a second lighting device, are stacked, the number of parts is large and the manufacturing cost is increased. There are problems such as thickening. Further, in order to increase the area, it is necessary to provide a large number of light sources for diffusion, and thus there is a problem that the manufacturing cost increases.
  • the illumination device of Patent Document 2 has a problem that it is difficult to increase the size of the light guide plate because the positional relationship between the plurality of prisms and the two types of light sources is determined with respect to the light guide plate having a predetermined area.
  • Some aspects of the present invention have been made in view of the above circumstances, and an object thereof is to provide a light control device capable of switching emitted light between light having directivity and scattered light.
  • a surface light source device includes a first light source unit that includes a first light emitting element, and emits light from the first light emitting element.
  • a second light source unit that emits light from the second light emitting element as light having an angular distribution wider than the angular distribution of light emitted from the first light source unit,
  • a light guide that causes light emitted from the first light source unit and light emitted from the second light source unit to be incident from an end surface and to be emitted from a main surface, and includes the first light source unit and the light source
  • the second light source unit is provided on one end surface of the plurality of end surfaces of the light guide, and lighting / extinguishing can be independently controlled.
  • any one of the first light source unit and the second light source unit includes an angular distribution of light emitted from the first light source unit and the second light source. You may provide the angle distribution conversion member for making different the angle distribution of the light inject
  • the first light source unit includes a concave mirror that reflects light emitted from the first light emitting element as the angle distribution conversion member, and the concave mirror includes: The cross-sectional shape when cut along a plane parallel to the main surface of the light guide body has at least part of a curved shape having a focal point, and the first light emitting element is a light emitting surface of the first light emitting element.
  • the light source from the first light emitting element may be reflected by the concave mirror and incident on the light guide.
  • the second light emitting element emits light having an angular distribution wider than the angular distribution of light emitted from the first light source unit, and the second light emission.
  • the light emitted from the element may enter the light guide without passing through the concave mirror.
  • the first light emitting element and the second light emitting element may be arranged such that surfaces opposite to each other's light emitting surface face each other.
  • the first light source unit includes the plurality of light emitting elements and the plurality of concave mirrors arranged along one end surface of the light guide,
  • the light emitting elements may be arranged along the boundary between adjacent concave mirrors.
  • the concave mirror has a linear shape when the concave mirror is cut along a plane perpendicular to the main surface of the light guide, and is perpendicular to the main surface of the light guide.
  • the first light emitting element is disposed along a direction perpendicular to the main surface of the light guide, and the second light emitting element is formed on the main surface of the light guide. You may arrange
  • the first light source unit includes a convex lens disposed in a recess of the concave mirror, and the focal position of the convex lens substantially coincides with the focal position of the concave mirror. It may be.
  • the concave mirror may be formed of a metal film or a dielectric multilayer film formed on a convex surface of the convex lens.
  • the first light source unit includes, as the angle distribution conversion member, a reflective element having a reflective surface that reflects light emitted from the first light emitting element,
  • the reflective element includes the reflective surface inclined at a constant angle with respect to the one end surface of the light guide, and a light exit surface facing the one end surface of the light guide,
  • One light emitting element may be disposed on one end face of the reflecting element, and light from the first light emitting element may be reflected by the reflecting surface and incident on the light guide.
  • the second light emitting element emits light having an angular distribution wider than the angular distribution of light emitted from the first light source unit, and the second light emission.
  • the light emitted from the element may enter the light guide without passing through the reflective element.
  • a plurality of the reflective elements may be provided for the one end surface of the light guide.
  • the reflective element has a wedge shape whose thickness decreases from a side closer to an end face on which the first light emitting element is disposed to a side farther from the end face.
  • the entire end surface facing the surface may be the reflecting surface.
  • the reflection element has a plurality of prism structures on a surface facing the light emission surface, and one inclined surface of the prism structure is the reflection surface. Also good.
  • the second light source unit includes a light scattering member that scatters light emitted from the second light emitting element as the angle distribution conversion member, Light emitted from the light emitting element may enter the light guide through the light scattering member.
  • the first light source unit includes a lens that substantially parallelizes light emitted from the first light emitting element as the angle distribution conversion member.
  • the light emitted from the light emitting element may enter the light guide through the lens.
  • the light guide may have a reflecting surface that forms a predetermined inclination angle with respect to the main surface in the light propagation direction.
  • the light guide has a wedge shape that decreases in thickness toward a side farther from the side closer to the one end surface, and the entire surface facing the main surface is the It may be a reflective surface.
  • the light guide has a plurality of prism structures on a surface facing the main surface, and one inclined surface of the prism structure is the reflection surface. Also good.
  • the surface light source device further includes a direction changing member for changing the traveling direction of the light emitted from the main surface of the light guide to a direction closer to the normal line of the main surface. Also good.
  • a display device includes the surface light source device and a display element that performs display using light emitted from the surface light source device.
  • An illumination device in still another aspect of the present invention includes the surface light source device.
  • the illumination device may include the first light source unit and the second light source unit of the surface light source device.
  • the modulated light source device includes a light source unit, a light guide body having the light source unit at an end thereof, and the light guide body between the light source unit and the light guide body or in the light source unit.
  • a light distribution conversion element disposed on a side opposite to the end of the light distribution conversion element, and the light distribution characteristic of the light distribution conversion element is variable.
  • the light distribution conversion element is provided on a surface of the light source unit opposite to a surface facing the one end surface of the light guide, and from the light source unit. It may be a parabolic mirror-shaped lens provided with a reflecting mirror having a reflecting surface for reflecting light.
  • the lens may have a hollow structure.
  • the lens may be filled with resin.
  • the reflection mirror may be made of a metal vapor deposition film.
  • the reflection mirror may be a dielectric mirror.
  • a scattering liquid crystal cell may be provided on the reflection surface of the reflection mirror.
  • the lens may be provided with a plurality of protrusions that can be taken in and out of the light source unit under the control of a micro electro mechanical system.
  • the reflection mirror is an electrochromic mirror, and is transmitted through the electrochromic mirror on a surface opposite to the surface facing the light source part of the electrochromic mirror. Reflecting means for reflecting the reflected light may be provided.
  • the light distribution conversion element may be provided between the light source unit and one end surface of the light guide.
  • the light distribution conversion element may be a scattering liquid crystal cell.
  • the light distribution conversion element may be a liquid crystal lens.
  • the light distribution conversion element may be a scatterer that can be inserted and removed between the light source unit and one end surface of the light guide.
  • the light distribution conversion element includes a light incident part disposed to face one end face of the light guide, the light incident part, and the one end face.
  • a gel capable of optical bonding; a scattering pattern provided on the one end face; and a pair of reflectors that sandwich a boundary between the gel and the one end face from the thickness direction of the light guide. May be.
  • the light distribution conversion element includes a wedge-shaped light guide and a prism that faces the light guide and has a light incident surface having a saw blade shape. May be.
  • the light guide may have a wedge shape.
  • a display device includes the light control device.
  • the illuminating device in the further another aspect of this invention is equipped with the said light control apparatus.
  • a surface light source device that can switch directivity, does not increase the number of parts and the manufacturing cost, and does not increase the thickness of the entire device. According to the present invention, it is possible to realize a surface light source device that can switch directivity and can maintain a uniform luminance before and after switching directivity. According to the present invention, it is possible to realize a display device and an illumination device including the surface light source device having the above-described effects. According to some aspects of the present invention, by using a light distribution conversion element that imparts directivity to light from the light source unit, light emitted from the light control device is converted into light having directivity and scattered light. Can be switched.
  • FIG. 2 is a cross-sectional view taken along the line A1-A1 'of FIG. It is a perspective view which shows the 1st light source part and the 2nd light source part in the surface light source device of this embodiment.
  • FIG. 4 is a cross-sectional view taken along line B1-B1 'of FIG.
  • FIG. 4 is a cross-sectional view taken along line C1-C1 ′ of FIG. It is a figure which shows the effect
  • FIG. 1 It is a figure which shows the simulation result of the illumination intensity distribution in the surface light source device of this embodiment. It is a figure which shows the simulation result of the illumination intensity distribution in the surface light source device of this embodiment. It is a figure which shows the simulation result of the illumination intensity distribution in the surface light source device of this embodiment. It is a figure which shows the simulation result of the illumination intensity distribution in the surface light source device of this embodiment. It is a figure which shows the simulation result of the illumination intensity distribution in the surface light source device of a comparative example. It is a figure which shows the simulation result of the illumination intensity distribution in the surface light source device of a comparative example. It is sectional drawing of the liquid crystal display device which is one structural example of the display apparatus of this invention. It is a schematic plan view which shows 9th Embodiment of a light modulation apparatus. FIG.
  • 32C is a cross-sectional view taken along line AA of FIG. 32A, showing a ninth embodiment of the light control device. It is a schematic sectional drawing which shows one Embodiment of a scattering liquid crystal cell. It is a figure explaining the case where a normal mode polymer dispersion liquid crystal is used as a polymer dispersion liquid crystal which comprises a scattering liquid crystal cell. It is a figure explaining the case where a normal mode polymer dispersion liquid crystal is used as a polymer dispersion liquid crystal which comprises a scattering liquid crystal cell. It is a figure explaining the case where a reverse mode polymer dispersion liquid crystal is used as a polymer dispersion liquid crystal which comprises a scattering liquid crystal cell.
  • FIG. 40B is a cross-sectional view taken along line B2-B2 of FIG. 40A.
  • FIG. 41B is a cross-sectional view taken along the line CC of FIG. 41A. It is the schematic top view which shows the state which inserted the scatterer between the light source part and the one end surface of a light guide. It is the front view seen from the one end surface side of a light guide.
  • FIG. 42B is a cross-sectional view taken along the line DD of FIG. 42A. It is a schematic sectional drawing which shows 12th Embodiment of a light modulation apparatus.
  • FIG. 57B is a cross-sectional view taken along line EE in FIG. 57A.
  • FIG. 57B is a cross-sectional view taken along line EE in FIG. 57A.
  • FIG. 57B is a cross-sectional view taken along line EE in FIG. 57A.
  • FIG. 57B is a cross-sectional view taken along line EE in FIG. 57A.
  • 20th Embodiment of a light modulation apparatus and is a general view. It is the figure which expanded the area
  • FIG. 1 is a perspective view showing the surface light source device of this embodiment.
  • FIG. 2 is a sectional view taken along line A1-A1 ′ of FIG.
  • FIG. 3 is a perspective view showing one light source in the surface light source device of the present embodiment.
  • 4A is a cross-sectional view taken along line BB ′ of FIG. 4B is a cross-sectional view taken along the line CC ′ of FIG.
  • the surface light source device 11 of the present embodiment includes a light source unit 12, a light guide 13, and a prism sheet 14 (direction changing member).
  • the light guide 13 has a function of causing light emitted from the light source unit 12 to enter from the end face and to be emitted from the main surface while propagating inside.
  • the prism sheet 14 has a function of changing the traveling direction of the light emitted from the main surface of the light guide 13 to a direction closer to the normal line of the main surface. The detailed configuration of the light source unit 12 will be described later.
  • the light guide 13 is a plate made of a resin having optical transparency such as acrylic resin.
  • the light guide 13 has a wedge shape in which the thickness gradually decreases from the side closer to the end surface 13 a where the light source unit 12 is provided to the side farther from the side. That is, as shown in FIG. 2, the cross-sectional shape of the light guide 13 when cut along a plane (yz plane) perpendicular to the first main surface 13b described later is a right triangle.
  • the end surface 13 a of the light guide 13 is a light incident surface on which light emitted from the light source unit 12 is incident.
  • the first main surface 13b (upper surface in FIG. 2) of the light guide plate 3 is a light emitting surface for emitting light incident on the inside.
  • the light propagation direction in the first main surface 13b of the light guide 13 is the y-axis direction
  • the direction orthogonal to the light propagation direction is the x-axis direction
  • the first main surface is orthogonal.
  • the direction (thickness direction of the light guide 13) is defined as the z-axis direction. That is, the “light propagation direction” in this specification means a direction in which light (indicated by a dashed line arrow L) propagates while reflecting in the yz section of the light guide 13 shown in FIG. Instead, it means the direction (indicated by solid arrow Y) in which light propagates when viewed from the normal direction of the first main surface 13b of the light guide 13.
  • the second main surface 13c (the lower surface in FIG. 2) facing the first main surface 13b of the light guide 13 is inclined with a certain inclination angle with respect to the first main surface 13b in the light propagation direction.
  • the inclination angle ⁇ 1 of the second main surface 13c with respect to the first main surface 13b (the angle between the first main surface 13b and the second main surface 13c, sometimes referred to as the tip angle of the light guide 13) is, for example, 2 °. Set to degree.
  • the second main surface 13c is provided with a reflection mirror 15 made of a metal film having a high light reflectance such as aluminum.
  • the reflection mirror 15 may be a metal film directly formed on the second main surface 13 c of the light guide 13, or a configuration in which a reflection plate manufactured separately from the light guide 13 is bonded. There may be.
  • the light source unit 12 has a configuration in which a plurality of light sources 16 are arranged in a line in a direction (x-axis direction) orthogonal to the light propagation direction Y.
  • the light source 16 includes a light source unit for high directivity (first light source unit) 113 and a light source unit for wide angle (second light source unit) 114.
  • the light source unit 113 for high directivity emits light having a high directivity because the angular distribution of the emitted light is relatively narrow.
  • the wide-angle light source unit 114 emits light having a relatively wide angular distribution and low directivity.
  • the high directivity light source unit 113 includes a first LED 17 (first light emitting element), a cylindrical lens 18 (convex lens), and a concave mirror 19. ing.
  • the cylindrical lens 18 is made of, for example, acrylic resin, phenyl-based or dimethyl-based silicon resin, or the like.
  • the cylindrical lens 18 is a so-called plano-convex lens in which one is a convex surface and the other is a flat surface. Since light is emitted from the flat surface 18a, the flat surface 18a is hereinafter referred to as a light emission surface.
  • the convex surface is a curved surface that is gently curved.
  • the convex surface has a curved shape having a focal point P1, as shown in FIG. 4A.
  • the cross-sectional shape of the convex surface 18b is a parabolic shape.
  • the curved surface 8b is linear as shown in FIG. 4B. That is, the convex surface 18b of the cylindrical lens 18 is a parabolic surface that has a curvature in the xy plane and has no curvature in the yz plane.
  • a concave mirror 19 is provided along the convex surface 18 b of the cylindrical lens 18.
  • the concave mirror 19 is made of a metal film having a high light reflectance such as aluminum directly formed on the convex surface 18 b of the cylindrical lens 18.
  • the concave mirror 19 may be composed of a dielectric multilayer film such as ESR. Since the convex surface 18b of the cylindrical lens 18 and the concave mirror 19 are in close contact, the shape of the concave mirror 19 is a parabolic surface reflecting the shape of the convex surface 18b. Therefore, the focal position of the concave mirror 19 coincides with the focal position of the cylindrical lens 18. The focal point is indicated by point P1 in FIG. 4A.
  • a configuration may be adopted in which a concave mirror (also referred to as an angle distribution conversion member) manufactured separately from the cylindrical lens 18 is bonded.
  • the light exit surface 18a of the cylindrical lens 18 is provided with a groove 110 having a depth that allows the first LED 17 to be inserted therein.
  • the cross-sectional shape of the bottom of the groove 110 when the cylindrical lens 18 is cut along the xy plane is rounded into an arc.
  • the first LED 17 is disposed inside the groove 110.
  • the first LED (also referred to as a first light emitting element) 17 is disposed so that the light emitting surface 17 a faces the concave mirror 19.
  • the first LED 17, the concave mirror 19 and the cylindrical lens 18 are set such that their positional relationship, dimensions, and shape are set so that the focal point P11 of the concave mirror 19 and the cylindrical lens 18 is located on the light emitting surface 17a. ing.
  • the first LED 17 Since the light emitting surface 17a of the first LED 17 faces the concave mirror 19, almost all of the light emitted from the light emitting surface 17a of the first LED 17 is directed to the concave mirror 19 and reflected by the concave mirror 19, The light exits from the light exit surface 18 a of the cylindrical lens 18. Therefore, among the light emitted from the light emitting surface 17 a of the first LED 17, there is almost no light emitted directly without being reflected by the concave mirror 19.
  • the first LED 17 is not particularly directional, and a general LED that emits light at a predetermined diffusion angle can be used.
  • a groove 110 is provided so as to penetrate from the upper surface to the lower surface of each cylindrical lens 18.
  • the first LED 17 is provided over the entire groove 110 so as to reach from the upper end to the lower end of the cylindrical lens 18.
  • Two wires (not shown) on the positive electrode side and the negative electrode side for supplying a current to the first LED 17 are drawn from the upper end or the lower end of the cylindrical lens 18. It is desirable that the two wires are led out to be aligned with either the upper end or the lower end of the cylindrical lens 18.
  • a slight gap 112 is provided between the first LED 17 and the groove 110.
  • the gap 112 may be filled with an optical adhesive or the like, or air may be present without filling anything.
  • a plurality of separate cylindrical lenses 18 are connected, but a lenticular lens having a structure in which these plurality of cylindrical lenses are integrated may be used.
  • the wide-angle light source unit 114 includes a second LED (also referred to as a second light emitting element) 115 as shown in FIGS. 3, 4A, and 4B.
  • the second LED 115 is arranged such that the light emitting surface 115 a faces the end surface 13 a of the light guide 13. Accordingly, the first LED 17 and the second LED 115 are arranged such that the surfaces opposite to the light emitting surfaces 17a and 115a face each other. In other words, the first LED 17 and the second LED 115 are arranged back to back. Therefore, the light from the second LED 115 enters the light guide 13 without passing through the cylindrical lens 18 or the concave mirror 19.
  • the heights (dimensions in the z-axis direction) of the first LED 17 and the second LED 115 may be different as in the present embodiment, or may be the same.
  • a wiring (not shown) for supplying a current to the second LED 115 is drawn out from the gap between the cylindrical lens 18 and the light guide 13.
  • Two wires (not shown) on the positive electrode side and the negative electrode side for supplying a current to the second LED 115 are drawn from the upper end or the lower end of the cylindrical lens 18. Similar to the first LED 17, it is desirable that the two wires are drawn out to be aligned with either the upper end or the lower end of the cylindrical lens 18.
  • the first LED 17 and the second LED 115 can be controlled to turn on / off independently.
  • the light emitting surface 115a of the second LED 115 faces the end surface 13a of the light guide 13, almost all of the light emitted from the light emitting surface 115a of the second LED 115 enters the light guide 13.
  • the light emitting surface 115a of the second LED 115 is in contact with the end surface 13a of the light guide 13, but the light emitting surface 115a of the second LED 115 is not necessarily in contact with the end surface 13a of the light guide 13. It does not have to be.
  • the second LED 115 a general LED that emits light at a predetermined diffusion angle can be used.
  • the prism sheet 14 is provided at a position facing the light exit surface 13b of the light guide 13 (above the light guide 13 in FIG. 2).
  • the prism sheet 14 is provided with a plurality of prism structures 111 extending in a direction orthogonal to the light propagation direction Y on one surface.
  • the prism sheet 14 is disposed so that the surface on which the plurality of prism structures 111 are provided faces the light exit surface 13 b of the light guide 13.
  • the cross-sectional shape of one prism structure 111 in the cross section cut along the yz plane is a right triangle.
  • the prism structure 111 includes a first surface 111a that is orthogonal to the light exit surface 13b of the light guide 13, and a second surface 111b that forms a predetermined tip angle ⁇ 2 with respect to the first surface 111a. Yes.
  • the operation of the surface light source device 11 configured as described above will be described. Since the light emitting surface 17a of the first LED 17 has a predetermined area, not all points on the light emitting surface 17a necessarily coincide with the positions of the concave mirror 19 and the focal point P11 of the cylindrical lens 18. However, for the sake of simplicity, the following description will be made assuming that the area of the light emitting surface 17a is sufficiently small and the light emitting surface 17a coincides with the focal point P11.
  • the light L11 emitted from the light emitting surface 17a of the first LED 17 is directed to the concave mirror 19 with a predetermined diffusion angle and reflected by the concave mirror 19.
  • the behavior of light in a plane (xy plane) parallel to the light exit surface 13b of the light guide 13 is considered.
  • the position of the light emitting surface 17a coincides with the focal point P11, the light L emitted from the first LED 17 can be incident on the concave mirror 19 at any angle. After being reflected by the concave mirror 19, it proceeds in a direction parallel to the optical axis of the concave mirror 19.
  • the diffused light immediately after being emitted from the light emitting surface 17a of the first LED 17 is converted into light reflected and collimated by the concave mirror 19, that is, light having high directivity.
  • the light L11 exits from the light exit surface 18a of the cylindrical lens 18 and enters the light guide 13.
  • the light L12 emitted from the light emitting surface 115a of the second LED 115 enters the light guide 13 with a predetermined diffusion angle. Therefore, the angular distribution of the light L12 emitted from the wide-angle light source unit 114 is wider than the angular distribution of the light L11 emitted from the high-directivity light source unit 113.
  • the concave mirror 19 has no curvature, so that the concave mirror 19 functions like a plane mirror. That is, the light L11 emitted from the first LED 17 is reflected by the concave mirror 19 at a reflection angle equal to the incident angle. Therefore, the light L ⁇ b> 11 is emitted from the cylindrical lens 18 and is incident on the light guide 13 while maintaining the diffusion angle immediately after being emitted from the light emitting surface 17 a of the first LED 17.
  • the light L12 emitted from the second LED 115 propagates through the light guide 13 while maintaining the diffusion angle immediately after being emitted from the light emitting surface 115a.
  • the light L11 is a plane (xy plane) parallel to the light exit surface 13b of the light guide 13 when it is emitted from the light exit surface 18a of the cylindrical lens 18. ), And has no directivity in a plane (yz plane) parallel to the light propagation direction Y and perpendicular to the light exit surface 13 b of the light guide 13.
  • Such light L11 enters the light guide 13 from the light incident surface (end surface) 13a and propagates inside the light guide 13.
  • the light L12 is emitted in a plane (xy plane) parallel to the light emission surface 13b of the light guide 13 and parallel to the light propagation direction Y and emitted from the light guide 13. There is no directivity in both planes (yz plane) perpendicular to the surface 13b.
  • Such light L ⁇ b> 12 propagates through the light guide 13.
  • the light L1 propagating through the light guide 13 is repeatedly reflected between the first main surface 13b (light emission surface) and the second main surface 13c (reflection surface) as shown in FIG. Meanwhile, the light guide 13 travels in the light propagation direction Y (right side in FIG. 2). Assuming that the first main surface and the second main surface are parallel, the incident angle of the light to the first main surface and the second main surface does not change even if light is repeatedly reflected.
  • the light guide 13 has a wedge shape in which the thickness gradually decreases with increasing distance from the light incident surface 13a side, and the second main surface 13c has a predetermined inclination angle with respect to the first main surface 13b. Have. Therefore, each time the light L1 is reflected by the first main surface 13b and the second main surface 13c, the incident angle on the first main surface 13b and the second main surface 13c becomes small.
  • the critical angle on the first main surface 13b (light emission surface) of the light guide 13 is shown. That is, the critical angle at the interface between the acrylic resin constituting the light guide 13 and the air is about 42 ° from Snell's law.
  • the total reflection condition is satisfied as long as the incident angle of the light L1 on the first main surface 13b is larger than 42 ° which is a critical angle. Therefore, the light L1 is totally reflected by the first main surface 13b.
  • the incident angle of the light L1 to the first main surface 13b becomes smaller than 42 ° which is a critical angle.
  • the total reflection condition is not satisfied, and the light L1 is emitted to the external space.
  • the light L1 is confined inside the light guide 13 while the incident angle on the first main surface 13b is larger than the critical angle, and the incident angle on the first main surface 13b becomes smaller than the critical angle.
  • the first main surface 13b is sequentially ejected. Since the light L1 is refracted when emitted from the first main surface 13b, the light having an incident angle of about 42 ° to the first main surface 13b is emitted as light having an emission angle of about 70 °.
  • the light L1 when viewed in a plane (yz plane) parallel to the light propagation direction Y and perpendicular to the light exit surface 13b of the light guide 13, the light L1 is directional at the point of incidence on the light guide 13. However, it has high directivity at the time of emission from the light guide 13.
  • the emission angle of the light L1 when emitted from the light guide 13 is about 70 °, and the light L1 is emitted in a substantially horizontal direction. Therefore, using the prism sheet 14, the light L ⁇ b> 1 emitted from the light guide 13 is raised in a direction close to the normal direction of the first main surface 13 b of the light guide 13.
  • a prism sheet 14 having a prism structure 111 with a tip angle ⁇ 2 of about 38.5 ° is used, and light L1 is incident from the first surface 111a of the prism structure 111 and reflected by the second surface 111b. By doing so, the light guide 13 can be raised in a substantially normal direction with respect to the first main surface 13b.
  • the second LED 115 is turned on as shown in FIG. Light may be emitted.
  • diffused light L12 having a wide angular distribution in the xy plane is emitted.
  • the optical path of the diffused light L12 is raised in the z-axis direction by the action of the light guide 13 and the prism sheet 14, the diffused light L12 having a wide angular distribution in the xz plane is emitted.
  • the surface light source device 11 of the present embodiment when used in a mode in which light close to parallel light having a narrow angular distribution is emitted, that is, a so-called high directivity mode, as shown in FIG. Is turned on and light is emitted from the light source unit 113 for high directivity.
  • a so-called high directivity mode as shown in FIG. Is turned on and light is emitted from the light source unit 113 for high directivity.
  • light L11 close to parallel light having a narrow angular distribution in the xy plane is emitted.
  • the optical path of the light L11 is raised in the z-axis direction by the action of the light guide 13 and the prism sheet 14, the diffused light L11 having a narrow angular distribution in the xz plane is emitted.
  • the first LED 17 and the second LED 115 can be controlled to be turned on and off independently, the first LED 17 and the second LED 115 can be turned on simultaneously.
  • the diffused light L12 having a wide angular distribution and the light L11 close to parallel light having a narrow angular distribution are mixed and emitted from the light guide 13.
  • a large amount of light is emitted in the normal direction of the first main surface 13b of the light guide 13, and as a whole, emitted light having a wide angular distribution is obtained. Therefore, when the first LED 17 and the second LED 115 are turned on simultaneously, the wide-angle mode is set.
  • the angle distribution in the yz plane (not shown) emits light having a somewhat narrow angle distribution due to the effect of using the wedge-shaped light guide 13. .
  • the present inventors performed a simulation on the angular distribution of light emitted from the surface light source device of this embodiment.
  • lighting design analysis software Light Tools (ver. 7.2) was used.
  • the simulation conditions are as follows: the planar dimension of the light guide 13 is 130 mm (x-axis direction) ⁇ 130 mm (y-axis direction), the width of the cylindrical lens 18 (x-axis direction) is 26 mm, and the depth on the optical axis of the cylindrical lens 18 ( y-axis direction) is 7.5 mm, the height of the cylindrical lens 18 (z-axis direction) is 4 mm, the width of the light emission surface of the first LED 17 and the second LED 115 (x-axis direction) is 1 mm, the first The height (z-axis direction) of the light emission surface of the LED 17 and the second LED 115 was 4 mm.
  • the number of rays was set to 100,000, and the detector mesh was set at 1 ° intervals.
  • FIG. 6 is a diagram comparing the angle distribution in the x-axis direction between the wide angle mode and the high directivity mode.
  • the horizontal axis in FIG. 6 represents the polar angle (°) with the normal direction of the first main surface 13b of the light guide 13 as a reference (0 °).
  • the vertical axis in FIG. 6 indicates the luminance normalized with the maximum luminance value being 1.
  • the solid line in FIG. 6 shows the angle distribution in the wide angle mode.
  • the broken line in FIG. 6 shows the angular distribution in the high directivity mode.
  • the surface light source device 11 of the present embodiment exhibits a wide angular distribution with a luminance of 0.2 or more over a polar angle in the range of ⁇ 60 ° to + 60 ° in the wide-angle mode.
  • the surface light source device 11 of the present embodiment exhibits a narrow angular distribution over a polar angle in the range of about ⁇ 3 ° to + 3 ° in the high directivity mode. In this way, the surface light source device 11 of the present embodiment can switch the directivity of the emitted light between the wide angle mode and the high directivity mode.
  • FIG. 7 is a diagram comparing the angular distribution in the high directivity mode in the x-axis direction and the y-axis direction.
  • the horizontal axis in FIG. 7 indicates the polar angle (°) with the normal direction of the first main surface 13b of the light guide 13 as a reference (0 °).
  • the vertical axis in FIG. 7 indicates the luminance normalized with the maximum luminance value being 1.
  • a broken line in FIG. 7 indicates a luminance distribution in the x-axis direction.
  • the solid line in FIG. 7 shows the luminance distribution in the y-axis direction.
  • the angular distribution in the x-axis direction is the same as the angular distribution shown in FIG. That is, the surface light source device 11 of the present embodiment exhibits a narrow angular distribution over polar angles in the range of about ⁇ 3 ° to + 3 °.
  • the angular distribution in the y-axis direction is wider than the angular distribution in the x-axis direction, but is narrow over a polar angle in the range of about ⁇ 10 ° to + 20 °.
  • An angular distribution is shown.
  • the angular distribution in the y-axis direction is asymmetric because even if the optical path of the emitted light is raised in the vertical direction by the prism sheet 14, it cannot be raised yet and is opposite to the end face 13 a of the light guide 13 ( This is probably because the proportion of light emitted toward the side where the polar angle is positive) is large.
  • the surface light source device 11 of the present embodiment it is not necessary to prepare two sets of light guides and to stack these two light guides when switching between two types of directivities. Therefore, it is possible to solve problems such as a large number of parts, a high manufacturing cost, and a large thickness of the entire lighting device.
  • the design for making the luminance of the light emitted from the light guide 13 uniform is effective for the light from either LED 17 or 115. To work. Therefore, it becomes easy to keep the luminance uniform before and after switching the directivity.
  • the second LED 115 is hidden from the back side of the first LED 17 when viewed from the concave mirror 19 side. Become. For this reason, when the first LED 17 is turned on, the area behind the first LED 17 is originally a shadow area, so that the shadow of the second LED 115 does not increase any more.
  • the light guide 118 of the surface light source device 117 of the present modification includes a plurality of prism structures 119 on the second main surface 118c side facing the first main surface 118b (light emission surface). ing.
  • Each prism structure 119 extends in a direction orthogonal to the light propagation direction Y.
  • the cross-sectional shape of the prism structure 119 in the cross section cut along the yz plane is a right triangle.
  • the prism structure 119 includes a first surface 119a that is orthogonal to the first main surface 118b of the light guide 118, and a second surface 119b that forms a predetermined tip angle ⁇ 2 with respect to the first surface 119a. ing.
  • the second surface 119b functions as a reflecting surface that reflects light propagating through the light guide 118.
  • the light guide 118 of the present modification has a plurality of divided reflection surfaces. Therefore, the light guide 118 of this modification can also give high directivity to the emitted light by the same action as the wedge-shaped light guide.
  • the wedge-shaped light guide is used, but instead of this configuration, the light guide shown in FIG. 9 may be used.
  • the surface light source device 121 of the present modification includes a light guide body 122 formed of parallel flat plates in which a first main surface 122b (light emission surface) and a second main surface 122c are parallel.
  • the second main surface 122c of the light guide 122 is provided with a plurality of grooves and printed matter (not shown) having a prismatic cross-sectional shape.
  • the plurality of grooves and printed matter are arranged so that the density is lower as the distance from the end surface 122a provided with the light source unit 12 is lower, and the density is higher as the distance from the end surface 122a is longer.
  • the light propagating through the light guide 122 is changed in reflection angle by a plurality of grooves and printed matter, and emitted from the light guide 122.
  • the light propagation direction Y does not change before and after switching the directivity, and therefore, the arrangement of the plurality of grooves and printed matter for making the brightness of the emitted light uniform is which LED 17, It works effectively against the light from 115. Therefore, it becomes easy to keep the luminance uniform before and after switching the directivity.
  • FIG. 10 is a perspective view showing a light source unit in the surface light source device of this embodiment.
  • FIG. 11 is a plan view showing the surface light source device of this embodiment.
  • the same components as those used in the first embodiment are denoted by the same reference numerals, and the description thereof is omitted.
  • the second LED is arranged back to back with the first LED.
  • the second LED 115 is disposed along the boundary between two adjacent concave mirrors 19.
  • the second LEDs 115 are not arranged at every boundary between the two adjacent concave mirrors 19 but are arranged at every other boundary.
  • the first LED 17 and the second LED 115 have the same size, but may be different as in the first embodiment.
  • 2nd LED115 is arrange
  • the light emitting surface 115a of the second LED 115 occupies a sufficient size with respect to the light emitting surface 18a of the cylindrical lens 18, the light emitting surface 115a of the second LED 115 may face the cylindrical lens 18. .
  • the light L12 from the second LED 115 enters the cylindrical lens 18, is reflected by the concave mirror 19, and then enters the light guide 13.
  • the installation position of the second LED 115 is greatly deviated from the focal point of the concave mirror 19, the light emitted from the second LED 115 and reflected by the concave mirror 19 is not collimated. As a result, diffused light can be obtained from the second LED 115 even when the light emitting surface 115a of the second LED 115 faces the cylindrical lens 18 side.
  • lighting in the high directivity mode can be realized by turning on the first LED 17, and lighting in the wide angle mode can be realized by turning on the second LED 115.
  • achieve illumination of a wide angle mode is the same as that of 1st Embodiment.
  • the same effect as that of the first embodiment can be obtained that a surface light source device that can keep the luminance uniform before and after switching the directivity without increasing the number of parts and the manufacturing cost can be realized. It is done.
  • the luminance distribution of light emitted from the cylindrical lens 18 has a tendency that the luminance of light emitted from the central portion of the cylindrical lens 18 is large and the luminance of light emitted from the end portion of the cylindrical lens 18 is small.
  • the second LED 115 is disposed along the boundary between two adjacent concave mirrors 19. Therefore, if the first LED 17 and the second LED 115 are simultaneously turned on in the wide-angle mode, the light from the second LED 115 is applied to an area where the light intensity of the first LED 17 is low. As a result, luminance unevenness can be reduced.
  • 2nd LED115 was arrange
  • the second LED 115 may be arranged as shown in FIG.
  • the second LEDs 115 are arranged on all the boundaries between two adjacent concave mirrors 19. Therefore, in one surface light source device 26, the number of the first LEDs 17 and the number of the second LEDs 115 may be the same or different.
  • FIG. 13 is a perspective view showing a light source unit in the surface light source device of this embodiment.
  • FIG. 14A is a side view showing the surface light source device of the present embodiment.
  • FIG. 14B is a plan view showing the surface light source device of the present embodiment.
  • symbol is attached
  • the second LED is arranged back to back with the first LED.
  • the second LED 115 is arranged along a direction parallel to the upper surface and the lower surface of the cylindrical lens 18. Has been. Therefore, the first LED 17 and the second LED 115 are arranged so that their longitudinal directions are orthogonal to each other.
  • the concave mirror 19 has a straight cross-sectional shape when cut along the yz plane, and has no curvature in a direction perpendicular to the first main surface 3 a of the light guide 13.
  • the concave mirror 19 has a focal point that continuously exists along the z-axis direction, but in the yz plane, the concave mirror 19 exists continuously along the x-axis direction.
  • the second LED 115 is arranged along the x-axis direction, the light emitting surface 115 a of the second LED 115 is shifted from the focal point of the concave mirror 19.
  • 2nd LED115 is arrange
  • the second LED 115 may be arranged such that the light emitting surface 115a faces the cylindrical lens 18. In that case, the light from the second LED 115 enters the cylindrical lens 18, is reflected by the concave mirror 19, and then enters the light guide 13. However, since the light emitting surface 115a of the second LED 115 is shifted from the focal point of the concave mirror 19, the light emitted from the second LED 115 and reflected by the concave mirror 19 is not collimated. As a result, diffused light can be obtained from the second LED 115 even when the light emitting surface 115a of the second LED 115 faces the cylindrical lens 18 side.
  • lighting in the high directivity mode can be realized by turning on the first LED 17, and lighting in the wide angle mode can be realized by turning on the second LED 115.
  • achieve illumination of a wide angle mode is the same as that of 1st Embodiment.
  • the same effect as that of the first embodiment can be obtained that a surface light source device that can keep the luminance uniform before and after switching the directivity without increasing the number of parts and the manufacturing cost can be realized. It is done.
  • the second LED was arrange
  • the second LED may be configured as shown in FIG.
  • the light source 130 according to the present modification includes a plurality of second LEDs 115 arranged at predetermined intervals along the x-axis direction.
  • FIG. 16 is a perspective view showing a light source unit in the surface light source device of this embodiment.
  • FIG. 17 is a plan view showing the surface light source device of this embodiment.
  • symbol is attached
  • the second LED 115 extends across the plurality of cylindrical lenses 18 and is parallel to the upper and lower surfaces of each cylindrical lens 18. It is arranged to extend long in the direction.
  • 2nd LED115 is arrange
  • the second LED 115 may be arranged such that the light emitting surface 115a faces the cylindrical lens 18. As described above, even when the light emitting surface 115a of the second LED 115 is directed toward the cylindrical lens 18, the diffused light can be obtained from the second LED 115.
  • 1st LED17 is alternately arrange
  • lighting in the high directivity mode can be realized by turning on the first LED 17, and lighting in the wide angle mode can be realized by turning on the second LED 115.
  • achieve illumination of a wide angle mode is the same as that of 1st Embodiment.
  • the same effect as that of the first embodiment can be obtained that a surface light source device that can keep the luminance uniform before and after switching the directivity without increasing the number of parts and the manufacturing cost can be realized. It is done.
  • FIG. 18 is a perspective view showing a light source unit in the surface light source device of this embodiment.
  • FIG. 19A is a plan view of the light source unit.
  • FIG. 19B is a side view of the light source unit.
  • FIG. 20 is a diagram for explaining the action of light in the light source unit for high directivity.
  • FIG. 21 is a diagram for explaining the effect of the present embodiment. 18 to 21, the same reference numerals are given to the same components as those used in the first embodiment, and the description thereof will be omitted.
  • the light source unit 136 includes a high directivity light source unit 137 (stacked in the thickness direction (z-axis direction) of the light guide 13 as shown in FIGS. 18 and 19B.
  • the first light source unit and a wide-angle light source unit 138 (second light source unit).
  • the high directivity light source unit 137 is arranged in the upper stage, and the wide angle light source unit 138 is arranged in the lower stage.
  • the wide-angle light source unit 138 may be disposed in the upper stage, and the high directivity light source unit 137 may be disposed in the lower stage.
  • the high directivity light source unit 137 includes a first LED 17 (first light emitting element), a wedge-shaped light guide rod 139 (also referred to as a reflective element or an angle distribution conversion member), And an incident angle adjusting prism 140.
  • the first LED 17 is provided on the end surface 139 a in the longitudinal direction of the wedge-shaped light guide bar 139.
  • the first LED 17 is in contact with the wedge-shaped light guide rod 139, and is fixed so that the light emitting surface 17a faces the end surface 139a of the wedge-shaped light guide rod 139.
  • the incident angle adjusting prism 140 is disposed between the wedge-shaped light guide rod 139 and the light guide 13.
  • the wedge-shaped light guide rod 139 is a rod body made of a resin having optical transparency such as acrylic resin.
  • the same material as that of the light guide 13 can be used.
  • the wedge-shaped light guide rod 139 has a wedge shape in which the width (dimension in the y-axis direction) gradually decreases from the side closer to the end surface 139a provided with the first LED 17 toward the far side. That is, as shown in FIG. 19A, the planar shape of the wedge-shaped light guide bar 139 when viewed from the normal direction of the first main surface 3a of the light guide 13 is a right triangle.
  • the end surface 139a of the wedge-shaped light guide rod 139 is a light incident surface on which light emitted from the first LED 17 is incident.
  • the first side surface 139b of the wedge-shaped light guide rod 139 (a surface perpendicular to the end surface 139a in FIG. 19A) is a light emitting surface that emits light incident on the inside.
  • the second side surface 139c (the inclined surface in FIG. 19A) facing the first side surface 139b of the wedge-shaped light guide rod 139 is an inclined surface that is inclined with a certain inclination angle with respect to the first side surface 139b in the light propagation direction X.
  • the second side surface 139c may be provided with a reflection mirror made of a metal film having a high light reflectance such as aluminum.
  • the reflection mirror may be a metal film directly formed on the second side surface 139c of the wedge-shaped light guide rod 139, or a configuration in which a reflector made separately from the wedge-shaped light guide rod 139 is bonded. It may be.
  • the incident angle adjusting prism 140 includes a plurality of prism structures 141 provided on one surface.
  • the incident angle adjusting prism 140 is disposed such that the surface on which the plurality of prism structures 141 are provided faces the light exit surface 39b of the wedge-shaped light guide rod 139.
  • the cross-sectional shape of the prism structure 141 in the cross section cut along the xy plane is a right triangle.
  • the prism structure 141 has a first surface 141a orthogonal to the light exit surface 39b of the wedge-shaped light guide rod 139, and a second surface 141b that forms a predetermined tip angle ⁇ 13 with respect to the first surface 141a. ing.
  • the wide-angle light source unit 138 includes three second LEDs 115 as shown in FIGS. 18 and 19A.
  • three LEDs are used as the second LED 115, but the number of LEDs is not particularly limited.
  • the second LED 115 is disposed so that the light emitting surface 115 a faces the end surface 13 a of the light guide 13. Therefore, the light emitted from the second LED 115 enters the light guide 13 without passing through the wedge-shaped light guide rod 139 and the incident angle adjusting prism 140.
  • As the second LED 115 a general LED that emits diffused light can be used.
  • the light L11 emitted from the first LED 17 enters the wedge-shaped light guide rod 139 and propagates in the x-axis direction through the inside of the wedge-shaped light guide rod 139.
  • the light L11 propagating through the inside of the wedge-shaped light guide rod 139 is repeatedly reflected between the first side surface 139b (light emitting surface) and the second side surface 139c (reflecting surface) while being guided by the wedge shape.
  • the light rod 139 travels in the light propagation direction X (upper side in FIG. 20).
  • the incident angle of the light to the first side surface and the second side surface does not change even if light is repeatedly reflected.
  • the width of the wedge-shaped light guide bar 139 gradually decreases as the distance from the end face 139a side increases. That is, the second side surface 139c has a predetermined inclination angle with respect to the first side surface 139b. Therefore, each time the light L11 is reflected by the first side surface 139b and the second side surface 139c, the incident angle to the first side surface 139b and the second side surface 139c becomes small.
  • the criticality at the first side surface 139b (light emission surface) of the wedge-shaped light guide rod 139 is determined.
  • the critical angle at the interface between the acrylic resin and the air constituting the wedge-shaped light guide rod 139 is about 42 ° from Snell's law.
  • the light L11 is repeatedly reflected between the first side surface 139b and the second side surface 139c, and when the incident angle of the light L11 to the first side surface 139b becomes smaller than 42 ° which is a critical angle, the total reflection condition The light L11 is emitted from the first side surface 139b to the external space.
  • the light L11 is confined inside the wedge-shaped light guide rod 139 while the incident angle on the first side surface 139b is larger than the critical angle, and the incident angle on the first side surface 139b becomes smaller than the critical angle.
  • the incident angle on the first side surface 139b becomes smaller than the critical angle.
  • the light L1 enters the wedge-shaped light guide rod 139 when viewed in a plane (xy plane) parallel to the light propagation direction X and perpendicular to the light exit surface 39b of the wedge-shaped light guide rod 139.
  • it does not have directivity, but has high directivity at the time of emission from the wedge-shaped light guide rod 139.
  • the emission angle of the light L11 when emitted from the wedge-shaped light guide rod 139 is about 70 °, and the light L11 is emitted toward the distal end side of the wedge-shaped light guide rod 139. Therefore, using the incident angle adjusting prism 140, the light L11 emitted from the wedge-shaped light guide rod 139 is raised in a direction close to the normal direction of the end face 13a (light incident end face) of the light guide 13. Specifically, using the incident angle adjusting prism 140 having the prism structure 141 with the tip angle ⁇ 2 of about 38.5 °, the light L11 is incident from the first surface 141a of the prism structure 141, and the second surface.
  • the light guide 13 By reflecting at 141 b, the light guide 13 can be raised in a substantially normal direction with respect to the end face 13 a. In this way, the incident angle adjusting prism 140 can adjust the incident angle of light incident on the end surface 13a of the light guide 13 while maintaining high directivity.
  • the wide-angle light source unit 138 As shown in FIG. 18, the light L12 emitted from the light emitting surface 115a of the second LED 115 enters the light guide 13 with a predetermined diffusion angle. Therefore, the angular distribution of the light L12 emitted from the wide-angle light source unit 138 is wider than the angular distribution of the light L11 emitted from the high-directivity light source unit 137.
  • the light L11 is in a plane (xy plane) parallel to the light exit surface 13b of the light guide 13 when it is emitted from the incident angle adjusting prism 140.
  • the plane (yz plane) parallel to the light propagation direction inside the light guide and perpendicular to the light exit surface 13b of the light guide 13 it has no directivity.
  • Such light L ⁇ b> 1 enters the light guide 13 from the light incident surface (end surface) 3 a and propagates inside the light guide 13.
  • the light L1 is parallel to the light propagation direction in the plane (xy plane) parallel to the light exit surface 13b of the light guide 13 and inside the light guide 13. There is no directivity in both planes (yz plane) perpendicular to the light exit surface 13b of the light body 13. Such light L1 propagates in the light guide 13.
  • the behavior until the lights L11 and L12 from the light source units 137 and 138 are emitted from the light guide 13 and the prism sheet 140 to the external space is the same as in the first embodiment.
  • lighting in the high directivity mode can be realized by turning on the first LED 5 of the light source unit 137 for high directivity, and the second LED 115 of the light source unit 138 for wide angle is realized.
  • wide-angle mode illumination can be realized.
  • the 1st LED17 and the 2nd LED115 are lighted simultaneously, the point which can implement
  • the same effect as that of the first embodiment can be obtained that a surface light source device that can keep the luminance uniform before and after switching the directivity without increasing the number of parts and the manufacturing cost can be realized. It is done.
  • the concave mirror 19 and the cylindrical lens 18 as in the first to fourth embodiments are used as means for giving directivity to the light emitted from the first LED 17, as shown on the right side of FIG. Due to the curved surface shape of the cylindrical lens 18, the dimension of the light source 16 in the light propagation direction (y-axis direction) inside the light guide is increased to some extent.
  • the wedge-shaped light guide rod 139 as in this embodiment is used, even if the dimensions in the x-axis direction are the same as shown on the left side of FIG.
  • the dimension in the direction (y-axis direction) can be made smaller than that of the concave mirror 19. As a result, according to this embodiment, it is possible to reduce the size of the surface light source device.
  • the surface light source device of the said embodiment was provided with 1 set of units which consist of 1st LED and a wedge-shaped light guide rod as a high directivity light source part.
  • the light source unit for high directivity may be configured as shown in FIG.
  • the surface light source device 143 according to the present modification includes a plurality of units each including a first LED 17 and a wedge-shaped light guide rod 139 as the light source unit 137 for high directivity. In this modification, three sets of units are provided, but the number of units is not particularly limited.
  • the number of the first LEDs 17 is larger than that of the surface light source device of the above embodiment, and thus the amount of light emitted from the high directivity light source unit 137 is increased. Can do.
  • the wedge-shaped light guide rod 139 is used as means for giving directivity to the light emitted from the first LED.
  • the light guide rod shown in FIG. 23 may be used.
  • the light source unit 145 for high directivity of the present modification includes a light guide bar 146 and a first LED 17 provided on the end surface of the light guide bar 146 in the longitudinal direction.
  • the light guide rod 146 is provided with a plurality of prism structures 147 on the second side surface 146c facing the first side surface 146b (light emission surface).
  • the planar shape of the prism structure 147 is a right triangle.
  • the prism structure 147 includes a first surface 147a and a second surface 147b that forms a predetermined tip angle with respect to the first surface 147a.
  • the second surface 147 b functions as a reflecting surface that reflects light propagating through the light guide rod 146.
  • the wedge-shaped light guide rod 139 has one continuous reflection surface, whereas the light guide rod 146 of this modification has a plurality of divided reflection surfaces. Therefore, the light guide bar 146 of this modification can also give high directivity to the emitted light by the same action as the wedge-shaped light guide bar 139.
  • FIGS. 24, 25A, and 25B The configuration of the light guide of the surface light source device of this embodiment is the same as that of the first embodiment, and the configuration of the light source unit is different from that of the first embodiment.
  • FIG. 24 is an exploded perspective view showing a light source unit in the surface light source device of this embodiment.
  • FIG. 25A is a plan view of the light source unit.
  • FIG. 25B is a side view of the light source unit. 24, FIG. 25A, and FIG. 25B, the same code
  • the light source unit 150 includes a highly directional light source unit 151 (stacked in the thickness direction (z-axis direction) of the light guide 13 (see FIG. 24 and FIG. 25B).
  • the first light source unit and a wide-angle light source unit 152 (second light source unit).
  • the light source unit 151 for high directivity is arranged at the lower stage, and the light source unit 152 for wide angle is arranged at the upper stage.
  • the wide-angle light source unit 152 may be disposed in the lower stage, and the high directivity light source unit 151 may be disposed in the upper stage.
  • the high directivity light source unit 151 includes a first LED 17 (first light emitting element), a wedge-shaped light guide bar 139 (reflective element), and an incident angle adjusting prism 140. It is equipped with. That is, the configuration of the high directivity light source unit 151 is the same as that of the fifth embodiment.
  • the wide-angle light source unit 152 includes a second LED 115 (second light emitting element), a wedge-shaped light guide rod 139 (reflective element), and a light scattering member 153.
  • the light scattering member 153 is disposed on the light emission side of the wedge-shaped light guide bar 139.
  • the light scattering member 153 is a light-transmitting member that has been processed to scatter light on the surface.
  • the processing for scattering the light is performed by a technique such as printing, polishing, or providing an uneven shape. Note that it is desirable that the scattering characteristics of the light scattering member 153 be adjusted so that the proportion of light that is scattered forward is increased as much as possible, and the proportion of light that is scattered backward is minimized.
  • the light source unit 151 for high directivity and the light source unit 152 for wide angle are arranged so that the first LED 17 and the second LED 115 are located on the opposite sides. Therefore, the wedge-shaped light guide rods 139 of the high directivity light source 151 and the wide-angle light source 152 are also arranged in opposite directions. This configuration is preferable because the wiring (not shown) for supplying current to the first LED 17 and the wiring (not shown) for supplying current to the second LED 115 do not interfere with each other. However, the first LED 17 and the second LED 115 may be located on the same side.
  • the light emitted from the first side surface 139 b of the wedge-shaped light guide rod 139 in the wide-angle light source unit 152 is scattered and emitted when passing through the light scattering member 153. Therefore, the angular distribution of light finally emitted from the wide-angle light source unit 152 is wider than the angular distribution of light emitted from the high-directivity light source unit 151.
  • the “light scattering member” in the present embodiment corresponds to an “angle distribution conversion member” in the claims.
  • the various angle distribution conversion members used in the first to fifth embodiments function in a direction in which light having low directivity is incident and the directivity of the light is increased.
  • the light scattering member 153 of this embodiment functions in a direction in which light having high directivity is incident and the directivity of the light is reduced.
  • the same effect as that of the first embodiment can be obtained that a surface light source device that can keep the luminance uniform before and after switching the directivity without increasing the number of parts and the manufacturing cost can be realized. It is done.
  • the surface light source device of the above-described embodiment includes a set of units each including a first LED and a wedge-shaped light guide bar as a high directivity light source unit, and the first LED and a wedge-shaped light guide bar as a wide-angle light source unit. And a unit consisting of a light scattering member.
  • the light source unit may be configured as shown in FIG.
  • the surface light source device 155 of the present modification includes a plurality of units each including the first LED 17 and a wedge-shaped light guide bar 139 as the high directivity light source unit 151.
  • the wide-angle light source unit 152 includes a plurality of units each including a second LED 115, a wedge-shaped light guide rod 139, and a light scattering member 153.
  • each of the light source units 151 and 152 includes three sets of units, but the number of units is not particularly limited.
  • the number of LEDs is increased as compared with the surface light source device of the above embodiment, and thus the amount of light emitted from each light source unit can be increased.
  • FIG. 27A is a plan view showing a light source unit in the surface light source device of the present embodiment.
  • FIG. 27B is a side view of the light source unit.
  • symbol is attached
  • the light source unit 158 includes a plurality of high directivity light source units 159 (first light source units) and a plurality of wide angle light source units 160 (see FIG. 27A and FIG. 27B). 2nd light source part).
  • the plurality of high directivity light source units 159 and the plurality of wide angle light source units 160 are alternately arranged along a direction (x-axis direction) perpendicular to the light propagation direction Y inside the light guide 13.
  • the light source unit 159 for high directivity includes a first LED 17 (first light emitting element) and a collimating lens (also referred to as an angle distribution converting member) 161.
  • a first LED 17 first light emitting element
  • a collimating lens also referred to as an angle distribution converting member
  • the collimating lens 161 has a function of substantially collimating the light emitted from the first LED 17.
  • the collimating lens 161 is disposed in contact with the end surface 13 a of the light guide 13.
  • the first LED 17 is disposed at a position separated from the collimating lens 161 by the focal length of the collimating lens 161.
  • the wide-angle light source unit 160 includes a second LED 115 (second light emitting element).
  • a second LED 115 second light emitting element
  • a general LED that emits diffused light can be used as the second LED 115.
  • the second LED 115 is disposed such that the light emitting surface is in contact with the end surface 13 a of the light guide 13.
  • the first LED 17 when the first LED 17 is turned on, the light L11 emitted from the first LED 17 is substantially collimated by the collimating lens 161 and is incident on the light guide 13.
  • the second LED 115 when the second LED 115 is turned on, the diffused light L12 emitted from the second LED 115 is incident on the light guide 13.
  • both the first LED 17 and the second LED 115 may be lit.
  • the same effect as that of the first embodiment can be obtained that a surface light source device that can keep the luminance uniform before and after switching the directivity without increasing the number of parts and the manufacturing cost can be realized. It is done.
  • FIG. 28A is a plan view showing the surface light source device of this embodiment.
  • 28B is a cross-sectional view taken along the line AA ′ of FIG. 28A.
  • 29A to 29C are diagrams showing simulation results of the illuminance distribution in the surface light source device of this embodiment.
  • 30A to 30C are diagrams illustrating simulation results of illuminance distribution in the surface light source device of the comparative example.
  • the surface light source device 181 of the present embodiment includes a light guide 182 made of parallel flat plates in which a first main surface 182b (light emission surface) and a second main surface 182c are parallel. ing.
  • a plurality of light extraction prisms 183 extending in a direction perpendicular to the light propagation direction Y (x-axis direction) are provided on the first main surface 182b of the light guide 182 at a predetermined interval.
  • the light extraction prism 183 is preferably made of a material having the same refractive index as that of the light guide 182.
  • the cross-sectional shape of the light extraction prism 183 is a so-called reverse taper shape in which the width on the side in contact with the first main surface 182b of the light guide 182 is narrow and the width on the side opposite to the first main surface 182b is wide.
  • the plurality of light extraction prisms 183 are not arranged at equal intervals. That is, the plurality of light extraction prisms 183 are provided such that the closer to the end surface 182a of the light guide 182 provided with the light source unit 12, the lower the density and the farther from the end surface 182a, the higher the density.
  • the light L ⁇ b> 1 emitted from the light source unit 12 is incident on one of the plurality of light extraction prisms 183 while propagating through the light guide 182.
  • the light L1 that has entered the light extraction prism 183 is reflected by the reflection surface 183a, and then the angle is changed, and the light L1 is extracted to the outside of the light guide 182.
  • the surface light source device 181 of the present embodiment the surface light source device that can keep the luminance uniform before and after switching the directivity without increasing the number of parts and the manufacturing cost can be realized. Similar effects can be obtained.
  • the high directivity light source unit 113 and the wide-angle light source unit 114 are arranged on one end surface 182a of the light guide 182. Therefore, the following effects can be obtained.
  • the amount of light extraction tends to be large on the light exit surface of the light guide near the light source and small on the side far from the light source. Therefore, the illuminance distribution on the light exit surface of the light guide becomes non-uniform.
  • the plurality of light extraction prisms 183 are arranged such that the density is lower as the distance from the end face 182a of the light guide 182 is lower, and the density is higher as the distance from the end face 182a is higher. Can be made more uniform.
  • the illumination device described in Patent Document 3 if two light source units are arranged on different end faces of the light guide, a plurality of light extraction prisms 183 for making the illuminance distribution uniform can be obtained.
  • the arrangement only works for one of the light source sections.
  • the light source unit for high directivity 113 and the light source unit for wide angle 114 are arranged on one end surface 182a of the light guide 182 so that light can be transmitted before and after switching the directivity.
  • the propagation direction Y does not change. Therefore, the arrangement of the plurality of light extraction prisms 183 for making the illuminance distribution uniform works effectively for both light source units 113 and 114. Therefore, it is easy to keep the illuminance distribution uniform before and after switching the directivity.
  • the inventors performed a simulation on the illuminance distribution on the light exit surface of the surface light source device of this embodiment and the surface light source device of the comparative example.
  • lighting design analysis software Light Tools (ver. 7.2) was used.
  • the simulation conditions were set in the same manner as in the first embodiment.
  • FIG. 29A shows the surface light source device of the present embodiment, in which light from the high directivity light source unit 113 and the wide angle light source unit 114 is incident from one end surface 182 a of the light guide 182.
  • FIG. 29B shows the illuminance distribution by light from the light source unit 113 for high directivity
  • FIG. 29C shows the illuminance distribution by light from the light source unit 114 for wide angle.
  • the arrangement of the plurality of light extraction prisms 183 was not sufficiently optimized, and the illuminance distribution could not be sufficiently uniformed.
  • the illuminance distribution hardly changes before and after switching the directivity. Therefore, if the arrangement of the plurality of light extraction prisms 183 is sufficiently optimized, the illuminance distribution can be sufficiently uniformed in both the high directivity mode and the wide angle mode.
  • FIG. 30A shows a surface light source device of a comparative example, in which light from the light source unit for high directivity is incident from the end surface 182a of the light guide 182 to guide light from the light source unit for wide angle. Incident light is incident from the end face 182d of the light body 182.
  • FIG. 30B shows an illuminance distribution by light from the wide-angle light source unit.
  • the arrangement of the light extraction prism 183 is optimized with respect to the light from the light source unit for high directivity arranged on the end surface 182a. Therefore, for the light from the wide-angle light source unit, as shown in FIG. 30B, the light extraction amount is large on the side close to the high directivity light source unit, and the light extraction amount is small on the side far from the light source. It was. Thus, in the surface light source device of the comparative example, it was found that the illuminance distribution changed greatly before and after the switching of directivity, and the illuminance distribution became non-uniform in either one of the modes.
  • FIG. 32A and 32B are schematic views showing a ninth embodiment of the light control device, FIG. 32A is a plan view, and FIG. 32B is a cross-sectional view taken along the line A2-A2 of FIG. 32A.
  • the light control device 210 is generally configured by a light source unit 211, a light guide 212, a scattering liquid crystal cell 213, and a parabolic mirror-shaped lens 215 including a reflection mirror 214.
  • the light guide 212 is disposed to face the light source unit 211.
  • the light guide 212 introduces light from the light source unit 211 from the one end face 212a side, and guides light from the light source unit 211 in the longitudinal direction.
  • the scattering liquid crystal cell 213 is provided between the light source unit 211 and the one end surface 212 a of the light guide 212.
  • the parabolic mirror-shaped lens 215 is provided on the surface opposite to the surface 211 a facing the one end surface 212 a of the light guide 212 of the light source unit 211.
  • the reflection mirror 214 has a reflection surface 214 a that reflects light from the light source unit 211.
  • the scattering liquid crystal cell 213 is used as a light distribution conversion element that changes the directivity of light from the light source unit 211.
  • the light distribution conversion element of this embodiment has a variable light distribution characteristic of changing the directivity of light from the light source unit. The configuration of the light distribution conversion element will be described below.
  • the scattering liquid crystal cell 213 is roughly composed of a polymer dispersed liquid crystal 221 and a pair of transparent conductive substrates 222 and 223 that sandwich the polymer dispersed liquid crystal 221.
  • the transparent conductive substrate 222 is roughly composed of a transparent substrate 224 and a transparent conductive film 225 provided on one surface 224a thereof.
  • the transparent conductive substrate 223 is roughly composed of a transparent substrate 226 and a transparent conductive film 227 provided on one surface 226a thereof.
  • FIG. 34A when a voltage is not applied between the transparent conductive substrates 222 and 223, the liquid crystal 231 is not oriented and is scattered like the random polymer 32. Therefore, the light incident on the scattering liquid crystal cell 213 from the transparent conductive substrate 223 side is scattered by the liquid crystal 231 and is emitted from the scattering liquid crystal cell 213 as scattered light.
  • FIG. 34A when a voltage is not applied between the transparent conductive substrates 222 and 223, the liquid crystal 231 is not oriented and is scattered like the random polymer 32. Therefore, the light incident on the scattering liquid crystal cell 213 from the transparent conductive substrate 223 side is scattered by the liquid crystal 231 and is emitted from the scattering liquid crystal cell 213 as scattered light.
  • FIG. 34A when a voltage is not applied between the transparent conductive substrates 222 and 223, the liquid crystal 231 is not oriented and is scattered like the random polymer 32. Therefore, the light incident on the scattering liquid crystal cell 213 from the transparent conductive substrate 223 side is scattered by
  • the liquid crystal 231 when a voltage is applied between the transparent conductive substrates 222 and 223, the liquid crystal 231 is aligned in the thickness direction of the scattering liquid crystal cell 213, so that the scattering liquid crystal cell 213 becomes transparent. Therefore, the light incident on the scattering liquid crystal cell 213 from the transparent conductive substrate 223 side is not scattered by the liquid crystal 231 and has directivity from the scattering liquid crystal cell 213 (the directivity in the thickness direction of the scattering liquid crystal cell 213). Light).
  • FIG. 35A A case where a reverse mode polymer dispersed liquid crystal is used as the polymer dispersed liquid crystal 221 constituting the scattering liquid crystal cell 213 will be described with reference to FIG. 35A and FIG. 35B.
  • the liquid crystal 241 As shown in FIG. 35A, when no voltage is applied between the transparent conductive substrates 222 and 223, the liquid crystal 241 is aligned with the liquid crystal polymer 243 in a direction perpendicular to the thickness direction of the scattering liquid crystal cell 213.
  • the scattering liquid crystal cell 213 becomes transparent.
  • the light incident on the scattering liquid crystal cell 213 from the transparent conductive substrate 223 side is not scattered by the liquid crystal 241 or the liquid crystal polymer 243, and has directivity from the scattering liquid crystal cell 213 (in the thickness direction of the scattering liquid crystal cell 213). Of light having a directivity of 2).
  • the liquid crystal 241 is oriented in the thickness direction of the scattering liquid crystal cell 213 and is different from the random polymer 242 and the liquid crystal polymer 243. In an oriented state. Therefore, light incident on the scattering liquid crystal cell 213 from the transparent conductive substrate 223 side is scattered by the liquid crystal 241, the random polymer 242 and the liquid crystal polymer 243, and is emitted from the scattering liquid crystal cell 213 as scattered light.
  • FIG. 36A and 36B the liquid crystal 231 constituting the scattering liquid crystal cell 213 is oriented as shown in FIG. 34B, or the liquid crystal 241 constituting the scattering liquid crystal cell 213 is oriented as shown in FIG. 35A.
  • FIG. 36A is a plan view.
  • FIG. 36B is a front view seen from one end surface side of the light guide. At this time, when the light from the light source unit 211 is reflected by the reflection surface 214 a of the reflection mirror 214 and the reflected light enters the scattering liquid crystal cell 213, the reflected light is scattered by the liquid crystal in the scattering liquid crystal cell 213.
  • the light guide 212 Without incident, light having directivity enters the light guide 212 from the one end surface 212a. Therefore, the light emitted from the upper surface 212 b of the light guide 212 is emitted at a narrow emission angle without spreading in the width direction of the light guide 212.
  • the emission angle of the light emitted from the upper surface 212b of the light guide 212 is extremely narrow, for example, as shown by the broken line in FIG.
  • FIG. 37A and 37B show a state where the liquid crystal 231 constituting the scattering liquid crystal cell 213 is not oriented as shown in FIG. 34A, or the liquid crystal 241 constituting the scattering liquid crystal cell 213 is oriented as shown in FIG. 35B. It is the schematic explaining the case where the light control apparatus 210 is used in the state which is not made.
  • FIG. 37A is a plan view.
  • FIG. 37B is a front view seen from one end surface side of the light guide.
  • the light from the light source unit 211 is reflected by the reflecting surface 214a of the reflecting mirror 214 and the reflected light enters the scattering liquid crystal cell 213, the reflected light is scattered by the liquid crystal in the scattering liquid crystal cell 213, It becomes scattered light and enters the light guide 212 from the one end face 212a. Therefore, the light emitted from the upper surface 212b of the light guide 212 spreads in the width direction of the light guide 212 and is emitted at a wide emission angle.
  • the emission angle of the light emitted from the upper surface 212b of the light guide 212 is widened, for example, as shown by the solid line in FIG.
  • the scattering liquid crystal cell 213 As described above, by using the scattering liquid crystal cell 213, the light emitted from the light control device 210 can be switched between directional light and scattered light. It suffices to install it only on the end face 212a side, and the light guide 212 may be used only in one layer without being laminated as in the prior art. Further, by installing the light source unit 211 only on the one end surface 212a side of the light guide 212, the traveling direction of the light from the light source unit 211 before and after switching the directivity of the light transmitted through the scattering liquid crystal cell 213 is does not change. Thereby, in the light guide 212, whether the design for making the emitted light uniform (such as thinning of the structure for raising the guided light) is either directional light or scattered light, Works effectively. Therefore, before and after switching the directivity of the light transmitted through the scattering liquid crystal cell 213, the uniformity of the luminance of the emitted light from the illumination device 10 can be maintained to some extent.
  • Examples of the light source constituting the light source unit 211 include an LED, an inorganic EL, and an organic EL.
  • the light guide 212 has a sheet shape and is composed of an inorganic material substrate made of glass, quartz or the like, a plastic substrate made of polyethylene terephthalate, polycarbonate, polyimide, polymethyl methacrylate (polymethyl methacrylate, PMMA), or the like. ing.
  • the transparent substrates 224 and 226 of the transparent conductive substrates 222 and 223 constituting the scattering liquid crystal cell 213 are in the form of a sheet, and are made of an inorganic material substrate made of glass, quartz, etc., polyethylene terephthalate, polycarbonate, polyimide, polymethyl methacrylate ( A plastic substrate made of polymethylmethacrylate, PMMA) or the like.
  • the transparent conductive films 225 and 227 of the transparent conductive substrates 222 and 23 constituting the scattering liquid crystal cell 213 are made of indium tin oxide (ITO) or the like.
  • Examples of the reflecting mirror 214 include an aluminum vapor deposition film formed on the outer surface of the lens 215, and a dielectric mirror attached to the outer surface of the lens 215.
  • the surface in contact with the lens 215 is a reflection surface 214a.
  • the lens 215 is made of a light transmissive material such as an inorganic material made of glass, quartz, or the like, or a plastic made of polymethyl methacrylate (polymethyl methacrylate, PMMA) or the like. Further, the lens 215 may have an outer skeleton portion made of the above-described material and may have a hollow structure inside, or may have a solid structure made entirely of the above-described material.
  • FIG. 38A is a schematic diagram illustrating a tenth embodiment of the light control device.
  • FIG. 38A is a side view.
  • FIG. 38B is an enlarged perspective view of a part of FIG. 38A.
  • the light control device 250 is generally configured by a light source unit 251, a light guide 252, and a liquid crystal lens 253.
  • the light guide 252 is disposed to face the light source unit 251.
  • the light guide 252 guides the light from the light source 251 in the longitudinal direction while the light from the light source 251 is introduced from the one end face 252a side.
  • the liquid crystal lens 253 is provided between the light source unit 251 and the one end surface 252a of the light guide 252.
  • a liquid crystal lens 253 is used as a light distribution conversion element that changes the directivity of light from the light source unit 251.
  • the liquid crystal lens 253 is not particularly limited, and a known liquid crystal lens can be used as long as the refractive index is changed by applying a voltage.
  • the liquid crystal lens 253 includes, for example, a first transparent substrate 254, a second transparent substrate 255, a first transparent electrode 256, a second transparent electrode 257, an insulating spacer 258, and a liquid crystal layer 259. A unit in which a plurality of units are connected is used.
  • the light source unit 251 and the light guide 252 are the same as those in the ninth embodiment.
  • FIG. 39A is a schematic side view illustrating the case where the light control device 250 is used without applying a voltage to the liquid crystal lens 253.
  • FIG. 39A since the liquid crystal constituting the liquid crystal lens 253 is aligned in the thickness direction of the liquid crystal lens 253, when light from the light source unit 251 enters the liquid crystal lens 253, the incident light is liquid crystal in the liquid crystal lens 253.
  • the light having directivity enters the light guide 252 from the one end face 252a without being scattered by the light. Therefore, the light emitted from the upper surface 252b of the light guide 252 is emitted at a narrow emission angle without spreading in the width direction of the light guide 252.
  • FIG. 39B is a schematic side view for explaining a case where a voltage is applied to the liquid crystal lens 253 and the light control device 250 is used.
  • the liquid crystal constituting the liquid crystal lens 253 is scattered without being oriented in the thickness direction of the liquid crystal lens 253, when the light from the light source unit 251 enters the liquid crystal lens 253, the incident light is the liquid crystal lens 253. It is scattered by the liquid crystal inside and becomes scattered light, and enters the light guide 252 from the one end face 252a. Therefore, the light emitted from the upper surface 252b of the light guide 252 spreads in the width direction of the light guide 252 and is emitted with a wide emission angle.
  • FIG. 40A and 40B are schematic views illustrating an eleventh embodiment of the light control device.
  • FIG. 40A is a plan view.
  • 40B is a cross-sectional view taken along line B2-B2 of FIG. 40A.
  • the light control device 260 is schematically configured by a light source unit 261, a light guide 262, a scatterer 263, and a parabolic mirror-shaped lens 265 including a reflection mirror 264.
  • the light guide 262 is disposed to face the light source unit 261.
  • the light guide 262 guides the light from the light source 261 in the longitudinal direction while the light from the light source 261 is introduced from the one end face 262a side.
  • the scatterer 263 is provided between the light source unit 261 and the one end surface 262a of the light guide 262 so as to be insertable / removable.
  • the parabolic mirror-shaped lens 265 is provided on the surface opposite to the surface 261 a facing the one end surface 262 a of the light guide 262 of the light source unit 261.
  • the reflection mirror 264 has a reflection surface 264 a that reflects light from the light source unit 261.
  • a scatterer 263 is used as a light distribution conversion element that changes directivity to light from the light source unit 261.
  • the scatterer 263 As a material of the scatterer 263, it is preferable to use a material in which light-scattering particles are dispersed in a light-transmitting resin.
  • particles (inorganic fine particles) made of an inorganic material for example, silica beads (refractive index: 1.44), alumina beads (refractive index: 1.63), titanium oxide beads (Refractive index anatase type: 2.50, rutile type: 2.70), zirconia bead (refractive index: 2.05), zinc oxide bead (refractive index: 2.00), barium titanate (BaTiO 3 ) ( Refractive index: 2.4) etc. are mentioned.
  • particles (organic fine particles) made of an organic material are used as the light scattering particles, for example, polymethyl methacrylate beads (refractive index: 1.49), acrylic beads (refractive index: 1.50), acrylic -Styrene copolymer beads (refractive index: 1.54), melamine beads (refractive index: 1.57), high refractive index melamine beads (refractive index: 1.65), polycarbonate beads (refractive index: 1.57) Styrene beads (refractive index: 1.60), crosslinked polystyrene beads (refractive index: 1.61), polyvinyl chloride beads (refractive index: 1.60), benzoguanamine-melamine formaldehyde beads (refractive index: 1.68) And silicone beads (refractive index: 1.50).
  • polymethyl methacrylate beads reffractive index: 1.49
  • acrylic beads refractive index: 1.50
  • acrylic -Styrene copolymer beads refractive index: 1.54
  • Examples of the resin material used by mixing with light scattering particles include acrylic resin (refractive index: 1.49), melamine resin (refractive index: 1.57), nylon (refractive index: 1.53), polystyrene ( Refractive index: 1.60), melamine beads (refractive index: 1.57), polycarbonate (refractive index: 1.57), polyvinyl chloride (refractive index: 1.60), polyvinylidene chloride (refractive index: 1.
  • polyvinyl acetate (refractive index: 1.46), polyethylene (refractive index: 1.53), polymethyl methacrylate (refractive index: 1.49), poly MBS (refractive index: 1.54), medium Density polyethylene (refractive index: 1.53), high density polyethylene (refractive index: 1.54), tetrafluoroethylene (refractive index: 1.35), poly (ethylene trifluoride) chloride (refractive index: 1.42), Polytetrafu Oroechiren (refractive index: 1.35), and the like.
  • the scatterer 263 can be inserted / removed between the light source 261 and the one end surface 262a of the light guide 262 by manual or micro electro mechanical system (MEMS) control (actuator).
  • MEMS micro electro mechanical system
  • the light source unit 261, the light guide 262, the reflection mirror 264, and the lens 265 are the same as those in the ninth embodiment described above.
  • FIG. 41A to 41C are schematic views showing a state in which no scatterer is inserted between the light source section and one end face of the light guide.
  • FIG. 41A is a plan view.
  • FIG. 41B is a front view seen from one end surface side of the light guide.
  • 41C is a cross-sectional view taken along line C2-C2 of FIG. 41A.
  • the light from the light source unit 261 is reflected by the reflection surface 264a of the reflection mirror 264, and the reflected light travels toward the light guide 262, but does not pass through the scatterer 263.
  • the light enters the light guide 262 from the one end surface 262a. Therefore, the light emitted from the upper surface 262b of the light guide 262 is emitted at a narrow emission angle without spreading in the width direction of the light guide 262.
  • FIG. 42A to 42C are schematic views showing a state in which a scatterer is inserted between the light source section and one end face of the light guide.
  • FIG. 42A is a plan view.
  • FIG. 42B is a front view seen from one end surface side of the light guide.
  • FIG. 42C is a sectional view taken along line D2-D2 of FIG. 42A.
  • FIG. 43 is a schematic cross-sectional view showing a twelfth embodiment of the light control device.
  • the light control device 270 is roughly composed of a light source 271, a light guide 272, a parabolic mirror-shaped lens 274 provided with a reflection mirror 273, a gel 275, a scattering pattern 276, and a pair of reflection plates 277 and 278. It is configured.
  • the light guide 272 is disposed to face the light source unit 271.
  • the light guide 272 guides the light from the light source 271 in the longitudinal direction while the light from the light source 271 is introduced from the one end face 272a side.
  • the parabolic mirror-shaped lens 274 is provided on the side opposite to the surface 271 a facing the one end surface 272 a of the light guide 272 of the light source unit 271.
  • the reflection mirror 273 has a reflection surface 273 a that reflects light from the light source unit 271.
  • the gel 275 is provided between the light source unit 271 and the lens 274 and the one end surface 272a of the light guide 272.
  • the gel 275 can optically bond the light source portion 271 and the lens 274 to the one end surface 272a of the light guide 272.
  • the scattering pattern 276 is provided on the one end surface 272 a of the light guide 272.
  • the pair of reflectors 277 and 278 is generally configured by a pair of reflectors 277 and 278 that sandwich the boundary between the gel 275 and the one end surface 272a of the light guide 272 from the thickness direction of the light guide 272. Yes.
  • the reflection mirror 273 and the lens 274 constitute a light incident part.
  • the gel 275 is used as a light distribution conversion element that changes the directivity to the light from the light source unit 271.
  • the gel 275 is not particularly limited, but any gel can be used as long as it is light transmissive and can optically bond the light source 271 and the lens 274 to the one end surface 272a of the light guide 272. Used. Further, the boundary portion between the gel 275 and the one end surface 272a of the light guide 272 is movable along the longitudinal direction of the light guide 272 by manual or micro electro mechanical system (MEMS) control (actuator). ing. Thereby, the gel 275 and the one end surface 272a of the light guide 272 are separated from each other by a predetermined distance and in contact with each other.
  • MEMS micro electro mechanical system
  • the scattering pattern 276 is an uneven pattern formed on the one end surface 272a of the light guide 272.
  • the reflecting plates 277 and 278 are not particularly limited, but materials made of a material having a refractive index lower than that of the gel 275 and the light guide plate 272 or a metal are used.
  • the light source 271, the light guide 272, the reflection mirror 273, and the lens 274, the same ones as those in the ninth embodiment described above are used.
  • FIG. 44A is a schematic cross-sectional view showing a state in which the light control device is used with the gel and one end face of the light guide spaced apart from each other with a predetermined interval.
  • the light from the light source unit 271 is reflected by the reflection surface 273a of the reflection mirror 273, and the reflected light passes through the gel 275 and further passes through the scatterer pattern 276, the reflected light becomes the scatterer pattern.
  • the light is scattered by 276 to become scattered light and enters the light guide 272 from the one end surface 272a. Therefore, the light emitted from the upper surface 272b of the light guide 272 spreads in the width direction of the light guide 272 and is emitted with a wide emission angle.
  • FIG. 44B is a schematic cross-sectional view showing a state where the light control device is used in a state where the gel and one end surface of the light guide are in contact with each other.
  • the reflected light is scattered.
  • the light having directivity is not scattered by the body pattern 276 and enters the light guide 272 from the one end surface 272a. Therefore, the light emitted from the upper surface 272b of the light guide 272 is emitted at a narrow emission angle without spreading in the width direction of the light guide 272.
  • the light incident portion may be a wedge-shaped light guide, a convex lens, or the like.
  • FIG. 45A and 45B are schematic views showing a thirteenth embodiment of the light control device.
  • FIG. 45A is a plan view.
  • FIG. 45B is a side view.
  • the light control device 280 is generally configured by a light source unit 281, a wedge-shaped light guide 282, a prism 283, a light guide 284, and a scattering liquid crystal cell 285.
  • the light guide 282 is disposed to face the light source unit 281.
  • Light from the light source unit 281 is introduced into the light guide 282 from the one end surface 282a side.
  • the prism 283 faces the side surface (the surface facing the inclined surface 282b) 282c of the light guide 282.
  • a light incident surface (a surface facing the side surface 282c of the light guide 282) 283a has a saw blade shape.
  • the light guide 284 guides the light from the light source unit 281 guided by the light guide 282 and the prism 283 in the longitudinal direction thereof.
  • the scattering liquid crystal cell 285 is provided between the prism 283 and the one end surface 284 a of the light guide 284.
  • a light guide 282 and a prism 283 are used as light distribution conversion elements that change the directivity of light from the light source unit 281.
  • the light guide 282 is made of an optically transparent material such as an inorganic material made of glass, quartz, or the like, or a plastic made of polymethyl methacrylate (polymethyl methacrylate, PMMA) or the like.
  • the prism 283 is made of a light-transmitting material such as an inorganic material made of glass, quartz or the like, or a plastic made of polymethyl methacrylate (polymethyl methacrylate, PMMA) or the like.
  • the light incident on the light guide 282 from the light source unit 281 is repeatedly reflected by the inclined surface 282b and the side surface 282c of the light guide 282, and the light guide 282 is passed through. Although propagating, a part of the light is transmitted through the side surface 282c.
  • the angle ⁇ at which the light transmitted through the side surface 282c of the light guide 282 exits the side surface 282c is less than the angle at which the light is totally reflected at the incident surface 283a of the prism 283, the light is scattered by the incident surface 283a of the prism 283. Instead, the light having directivity enters the light guide 284 from the one end face 284a. Therefore, the light emitted from the upper surface 284 b of the light guide 284 is emitted at a narrow emission angle without spreading in the width direction of the light guide 284.
  • the light from the light source unit 281 is opposed to the wedge-shaped light guide 282 to which the light is introduced from the one end face 282a side, and the side 282c of the light guide 282, and the light incident surface 283a has a saw blade shape.
  • the prism 283 formed the light emitted from the light control device 280 can be changed to light having directivity.
  • FIG. 48 is a schematic plan view showing a fourteenth embodiment of the light control device, and shows a parabolic mirror-shaped lens constituting the light control device.
  • the parabolic mirror-shaped lens 291 of the present embodiment is provided on the side opposite to the surface 2101 a facing the one end surface of the light guide (not shown) of the light source unit 2101.
  • the lens 291 includes a reflection mirror 292 having a reflection surface 292 a that reflects light from the light source unit 2101, and a three-scattering liquid crystal cell 293 provided along the reflection surface 292 a of the reflection mirror 292.
  • a lens 291 including a scattering liquid crystal cell 293 is used as a light distribution conversion element that changes the directivity of light from the light source unit 2101.
  • the directivity of light emitted from the light control device varies depending on the thickness of the scattering liquid crystal cell 293 and the refractive index difference between the lens 291 and the scattering liquid crystal cell 293. Therefore, in order to reduce the influence on the directivity of the emitted light from the light control device, it is preferable that the thickness of the scattering liquid crystal cell 293 is thin, and the difference in refractive index between the lens 291 and the scattering liquid crystal cell 293 is small. preferable.
  • the light source unit 2101 and the lens 291 are the same as those in the ninth embodiment.
  • FIG. 49A when no voltage is applied to the scattering liquid crystal cell 293, the liquid crystal is aligned in a direction perpendicular to the thickness direction of the scattering liquid crystal cell 293, so that the scattering liquid crystal cell 293 becomes transparent. Therefore, even if the light from the light source unit 2101 is reflected by the reflection surface 292a of the reflection mirror 292 and the reflected light passes through the scattering liquid crystal cell 293, the reflected light is not scattered by the liquid crystal, and the scattered liquid crystal.
  • Light is emitted from the cell 293 as light having directivity.
  • the liquid crystal is aligned in the thickness direction of the scattering liquid crystal cell 293. Accordingly, when light from the light source unit 2101 is reflected by the reflection surface 292a of the reflection mirror 292 and the reflected light enters the scattering liquid crystal cell 293, the light is scattered by the liquid crystal and scattered from the scattering liquid crystal cell 293. Emits light.
  • a normal mode polymer dispersed liquid crystal may be used as the polymer dispersed liquid crystal constituting the scattering liquid crystal cell 293.
  • the directivity of outgoing light depending on whether or not voltage is applied to the scattering liquid crystal cell 293 is opposite to that when reverse mode polymer dispersed liquid crystal is used.
  • FIG. 50 is a schematic plan view showing the fifteenth embodiment of the light control device, and shows a parabolic mirror-shaped lens that constitutes the light control device.
  • the parabolic mirror-shaped lens 2111 of this embodiment is moved in and out of the light source unit 2121 side by a reflection mirror 2112 having a reflection surface 2112a that reflects light from the light source unit 2121 and a micro electro mechanical system (MEMS) control (actuator).
  • MEMS micro electro mechanical system
  • actuator micro electro mechanical system
  • a plurality of possible projections 2113 are provided at predetermined intervals along the reflection surface 2112 a of the reflection mirror 2112.
  • a lens 2111 provided with protrusions 2113 is used as a light distribution conversion element that changes the directivity of light from the light source unit 2121.
  • FIG. 51A is a schematic plan view showing a state in which the light control device is used without projecting the plurality of protrusions 2113 on the light source unit 2121 side.
  • the light from the light source unit 2121 is reflected by the reflecting surface 2112a of the reflecting mirror 2112 and the reflected light is incident on the lens 2111 again.
  • the reflected light is not scattered in the lens 2111 and is reflected from the lens 2111. It emits as directional light.
  • FIG. 51B is a schematic plan view illustrating a state in which a plurality of protrusions 2113 are protruded toward the light source unit 2121 and the light control device is used.
  • the light from the light source unit 2121 is reflected by the reflection surface 2112a of the reflection mirror 2112, and the reflected light is incident on the lens 2111 again.
  • the reflected light is scattered by the plurality of protrusions 2113, and the lens 2111 To be emitted as scattered light.
  • the protrusion 2113 is accommodated (retracted) inside the reflection surface 2112a of the reflection mirror 2112, and a groove or hole is formed in the reflection surface 2112a of the reflection mirror 2112.
  • the reflected light may be scattered.
  • FIG. 52 is a schematic plan view illustrating the sixteenth embodiment of the light control device, and is a diagram illustrating a light source unit and a parabolic mirror-shaped lens that constitute the light control device.
  • the light source unit 2131 is provided so as to be movable in a parabolic mirror-shaped lens 2132. That is, the light source unit 2131 has a light emission surface 2131a that is on the same plane as a surface (hereinafter referred to as “one surface”) 2132a that faces the light guide (not shown) of the lens 2132.
  • the lens 2132 is movable in a direction perpendicular to the one surface 2132a until the exit surface 2131a is located inside the lens 2132.
  • the lens 2132 includes a reflection mirror 2133 having a reflection surface 2133a that reflects light from the light source unit 2131.
  • the light source part 2131 the thing similar to the above-mentioned 9th Embodiment is used.
  • a lens 2132 is used as a light distribution conversion element that changes directivity to light from the light source unit 2131.
  • the light source unit 2131 has a light output surface 2131a on the same surface as the surface 2132a facing the light guide (not shown) of the lens 2132, and the focus of the output light on one end surface of the light guide. Is provided to fit. Therefore, when the light source unit 2131 is located at this position, light incident on the light guide from the light source unit 2131 propagates through the light guide as directional light. On the other hand, when the emission surface 2131a of the light source unit 2131 is inside the one surface 2132a of the lens 2132, the focus of the emission light from the light source unit 2131 does not match the one end surface of the light guide. Therefore, when the light source unit 2131 is present at this position, the light incident on the light guide from the light source unit 2131 propagates through the light guide as scattered light.
  • FIG. 53 is a schematic sectional view showing a seventeenth embodiment of the light control device.
  • the light control device 2140 is generally configured by a light source unit 2141, a light guide 2142, and a parabolic mirror-shaped lens 2144 including a reflection mirror 2143.
  • the light guide 2142 is disposed to face the light source unit 2141.
  • the light guide 2142 guides the light from the light source unit 2141 in the longitudinal direction while the light from the light source unit 2141 is introduced from the one end surface 2142a side.
  • the parabolic mirror-shaped lens 2144 is provided on the side opposite to the surface 2141a facing the one end surface 2142a of the light guide 2142 of the light source unit 2141.
  • the reflection mirror 2143 has a reflection surface 2143 a that reflects light from the light source unit 2141.
  • the light guide 2142 and the lens 2144 are arranged so as to face each other with the light source unit 2141 interposed therebetween. That is, a gap due to the thickness of the light source unit 2141 is formed between the light guide 2142 and the lens 2144.
  • the wirings 2145 and 2146 of the light source unit 2141 are connected to a power source (not shown) through the gap.
  • a lens 2144 is used as a light distribution conversion element that changes the directivity of light from the light source unit 2141.
  • the light source unit 2141 is disposed at the center of a surface (hereinafter referred to as “one surface”) 2144a of the lens 2144 facing the light guide 2142.
  • the lens 2144 is rotatable around the light source unit 2141.
  • the light source unit 2141 As the light source unit 2141, the light guide 2142, the reflection mirror 2143, and the lens 2144, the same ones as those in the ninth embodiment described above are used.
  • the focal point of the emitted light from the light source unit 2141 is the one end surface 2142a of the light guide 2142. Does not fit. Therefore, when the lens 2144 is present at this position, light incident on the light guide 2142 from the light source unit 2141 propagates in the light guide 2142 as scattered light.
  • FIG. 55 is a schematic sectional view showing an eighteenth embodiment of the light control device.
  • the light control device 2150 is generally configured by a light source unit 2151, a light guide 2152, and a parabolic mirror-shaped lens 2154 including a reflection mirror 2153.
  • the light guide 2152 is disposed to face the light source unit 2151.
  • the light guide 2152 guides the light from the light source 2151 in the longitudinal direction while the light from the light source 2151 is introduced from the one end face 2152a side.
  • the parabolic mirror-shaped lens 2154 is provided on the surface opposite to the surface 2151 a facing the one end surface 2152 a of the light guide 2152 of the light source unit 2151.
  • the reflection mirror 2153 has a reflection surface 2153 a that reflects light from the light source unit 2151.
  • the light guide 2152 and the lens 2154 are disposed so as to face each other with the light source unit 2151 interposed therebetween. That is, a gap due to the thickness of the light source unit 2151 is formed between the light guide 2152 and the lens 2154.
  • the wirings 2155 and 2156 of the light source unit 2151 are connected to a power source (not shown) through the gap.
  • a lens 2154 is used as a light distribution conversion element that changes the directivity to light from the light source unit 2151.
  • the light source unit 2151 is disposed at the center of a surface (hereinafter referred to as “one surface”) 2154a of the lens 2154 facing the light guide 2152.
  • the light source unit 2151 is rotatable on one surface 2154a of the lens 2154.
  • the light source unit 2151 As the light source unit 2151, the light guide body 2152, the reflection mirror 2153, and the lens 2154, the same ones as those in the ninth embodiment described above are used.
  • the focal point of the emitted light from the light source unit 2151 is one end surface 2152a of the light guide 2152a. Does not fit. Therefore, when the lens 2154 is at this position, the light incident on the light guide 2152 from the light source unit 2151 propagates in the light guide 2152 as scattered light.
  • FIG. 57A and 57B are schematic views showing a nineteenth embodiment of the light control device, and FIG. 57A is a plan view.
  • FIG. 57B is a cross-sectional view taken along line E2-E2 of FIG. 57A.
  • the light control device 2160 is generally configured by a light source unit 2161, a wedge-shaped light guide 2162, a scattering liquid crystal cell 2163, a parabolic mirror-shaped lens 2165 including a reflection mirror 2164, and a prism 2166.
  • the wedge-shaped light guide 2162 is disposed to face the light source portion 2161.
  • the wedge-shaped light guide 2162 introduces the light from the light source 2161 from the one end face 2162a side and guides the light from the light source 2161 in the longitudinal direction.
  • the scattering liquid crystal cell 2163 is provided between the light source unit 2161 and the one end surface 2162a of the light guide 2162.
  • the parabolic mirror-shaped lens 2165 is provided on the surface opposite to the surface 2161a facing the one end surface 2162a of the light guide 2162 of the light source unit 2161.
  • the reflection mirror 2164 has a reflection surface 2164 a that reflects light from the light source unit 2161.
  • the prism 2166 is provided on the upper surface 2165b of the lens 2165. In the prism 2166, a surface 2166a facing the upper surface 2165b has a saw blade shape.
  • a scattering liquid crystal cell 2163 is used as a light distribution conversion element that changes the directivity to light from the light source unit 2161.
  • the light guide 2162 is made of a light-transmitting material such as an inorganic material made of glass, quartz, or the like, or a plastic made of polymethyl methacrylate (polymethyl methacrylate, PMMA) or the like.
  • the prism 2166 is made of a light-transmitting material such as an inorganic material made of glass, quartz or the like, or a plastic made of polymethyl methacrylate (polymethyl methacrylate, PMMA) or the like.
  • the light source unit 2161 As the light source unit 2161, the scattering liquid crystal cell 2163, and the reflection mirror 2164, the same ones as in the ninth embodiment are used.
  • the light control device 2160 for example, in a state where the liquid crystal constituting the scattering liquid crystal cell 2163 is aligned, the light from the light source unit 2161 is reflected by the reflecting surface 2164a of the reflecting mirror 2164, and the reflected light is scattered liquid crystal.
  • the reflected light is not scattered by the liquid crystal in the scattering liquid crystal cell 2163 but enters the light guide 2162 from one end surface 2162 a as directional light.
  • the light incident on the light guide 2162 is light that does not spread in the width direction of the light guide 2162.
  • the light incident on the light guide 2162 is repeatedly reflected on the upper surface 2162b and the slope 2162c of the light guide 2162, and spreads in the thickness direction of the light guide 2162 as it propagates in the light guide 2162.
  • the light has no light. Therefore, the light emitted from the upper surface 2162b of the light guide 2162 is emitted at a narrow emission angle without spreading in the width direction and the thickness direction of the light guide 2162. For example, as shown in FIG. 7, the emission angle of light emitted from the upper surface 2162b of the light guide 2162 becomes extremely narrow in the width direction and the thickness direction of the light guide 2162.
  • FIG. 58A and 58B are schematic plan views showing the twentieth embodiment of the light control device.
  • FIG. 58A is an overall view.
  • 58B is an enlarged view of a region surrounded by a broken line ⁇ in FIG. 58A.
  • the light control device 2170 is generally configured by a light source unit 2171, a light guide 2172, a parabolic mirror-shaped lens 2174 including an electrochromic mirror 2173, and a reflection unit 2175.
  • the light guide 2172 is disposed to face the light source unit 2171.
  • the light guide 2172 guides the light from the light source part 2171 in the longitudinal direction while the light from the light source part 2171 is introduced from the one end face 2172a side.
  • the parabolic mirror-shaped lens 2174 is provided on the surface opposite to the surface 2171a facing the one end surface 2172a of the light guide 2172 of the light source unit 2171.
  • the electrochromic mirror 2173 has a reflection surface 2173a that reflects light from the light source unit 2171.
  • the reflection means 2175 is provided on the surface of the electrochromic mirror 2173 opposite to the surface facing the light source unit 2171.
  • the reflection means 2175 reflects the light transmitted through the electrochromic mirror 2173.
  • a plurality of units each including a light source unit 2171, an electrochromic mirror 2173, a lens 2174, and a reflection unit 2175 are provided along the one end surface 2172 a of the light guide 2172.
  • a lens 2174 provided with an electrochromic mirror 2173 is used as a light distribution conversion element that changes the directivity of light from the light source unit 2171.
  • the electrochromic mirror 2173 can switch between reflection and transmission of light on the reflection surface 2173a by application of an electric field.
  • a general mirror (reflection mirror) is provided on the inner side surfaces 2175a, 2175b, and 2175c of the reflection means 2175, or a scatterer is provided as in the above-described eleventh embodiment. Thereby, the light emitted from the light source unit 2171 and transmitted through the electrochromic mirror 2173 can be reflected to the light guide 2172 side.
  • the same ones as those in the ninth embodiment described above are used.
  • the reflecting means 2175 is made of a light transmissive material such as an inorganic material made of glass, quartz, or the like, or a plastic made of polymethyl methacrylate (polymethyl methacrylate, PMMA) or the like. Further, the reflecting means 2175 may have an outer skeleton portion made of the above-mentioned material and an inside having a hollow structure, or may have a solid structure made entirely of the above-described material.
  • FIG. 59A is a schematic plan view showing a state in which the light control device is used when a voltage is applied to the electrochromic mirror 2173.
  • FIG. 59A shows a state in which the light control device is used when a voltage is applied to the electrochromic mirror 2173.
  • light from the light source unit 2171 is reflected by the reflection surface 2173a of the electrochromic mirror 2173, and the reflected light is scattered by mirrors and scatterers provided on the inner surfaces 2175a, 2175b, and 2175c of the reflection means 2175.
  • the light enters the light guide 2172 from the one end surface 2172a as light having directivity. Therefore, the light emitted from the upper surface 2172b of the light guide 2172 is emitted at a narrow emission angle without spreading in the width direction of the light guide 2172.
  • FIG. 59B is a schematic plan view showing a state in which the light control device is used when no voltage is applied to the electrochromic mirror 2173.
  • light from the light source unit 2171 passes through the electrochromic mirror 2173, and the transmitted light is scattered by mirrors and scatterers provided on the inner side surfaces 2175a, 2175b, and 2175c of the reflecting means 2175, and the scattered light.
  • the light enters the light guide 2172 from the one end surface 2172a. Therefore, the light emitted from the upper surface 2172b of the light guide 2172 spreads in the width direction of the light guide 2172 and is emitted with a wide emission angle.
  • FIG. 31 an example of a display device including the surface light source device of the above embodiment is shown.
  • the present embodiment is an example of a liquid crystal display device that includes the surface light source device of the first embodiment as a backlight.
  • the liquid crystal display device 165 of this embodiment includes a backlight 166 (surface light source device), a first polarizing plate 167, a liquid crystal panel (also referred to as a liquid crystal cell) 168, a second A polarizing plate 169.
  • the backlight 166 is disposed on the surface 168b side of the liquid crystal panel 168 opposite to the display screen 168a.
  • the liquid crystal panel 168 is schematically illustrated as a single plate. The observer views the display from the upper side of the liquid crystal display device 165 in FIG. 31 in which the second polarizing plate 169 is disposed.
  • the side on which the second polarizing plate 169 is disposed is referred to as a viewing side
  • the side on which the backlight 166 is disposed is referred to as a back side.
  • the backlight 166 is composed of any of the light control devices of the first to twentieth embodiments described above.
  • the light emitted from the backlight 166 is modulated by the liquid crystal panel 168, and a predetermined image, characters, or the like is displayed by the modulated light.
  • the liquid crystal panel 168 for example, an active matrix transmissive liquid crystal panel can be used.
  • the liquid crystal panel is not limited to an active matrix transmissive liquid crystal panel, and does not include, for example, a transflective (transmissive / reflective) liquid crystal panel and each pixel includes a switching thin film transistor (hereinafter abbreviated as TFT).
  • TFT switching thin film transistor
  • a simple matrix type liquid crystal panel may be used. Since a known general liquid crystal panel can be used for the liquid crystal panel 168, a detailed description of the configuration is omitted.
  • the liquid crystal television 170 of this configuration example includes the liquid crystal display device 165 of this embodiment as a display screen.
  • a liquid crystal panel 168 is disposed on the viewer side (front side in FIG. 63), and a backlight 166 (surface light source device) is disposed on the side opposite to the viewer (back side in FIG. 63).
  • a backlight 166 including the surface light source device 11 of the first embodiment capable of switching directivity is used. Therefore, by setting the backlight 166 to the high directivity mode, light emitted to the viewer side of the liquid crystal display device 165 (the display screen 168a side of the liquid crystal panel 168) is not diffused. This is suitable when a person watches a liquid crystal television from the front of the screen. Further, by setting the backlight 166 to the wide angle mode, light emitted to the viewer side of the display device 165 (the display screen 168a side of the liquid crystal cell 168) is diffused, so that the viewing angle can be widened.
  • the viewing angle of the display device 165 can be adjusted by using any one of the dimming devices of the first to twentieth embodiments described above as the backlight 166.
  • FIG. 64A shows a table lamp 175 provided with the light source unit of the above embodiment.
  • FIG. 64B shows the light source unit 12 of the desk lamp 175, which includes a high directivity light source unit 113 and a wide-angle light source unit 114.
  • a narrow range can be illuminated as shown by a solid arrow in FIG. 64A.
  • a wide range can be illuminated as shown by the dashed arrows in FIG. 64B.
  • FIG. 65A shows a table lamp 176 provided with a light source unit 12a having a circular irradiation surface.
  • FIG. 65B shows the light source unit 12a of the desk lamp 176, which includes a highly directional light source unit 113a having a circular concave mirror and a wide-angle light source unit 114a.
  • the desk lamp 176 by setting the light source unit 12a to the high directivity mode, a narrow range can be illuminated as shown by the dashed-dotted arrow in FIG. 65A.
  • the light source unit 112a By setting the light source unit 112a to the wide-angle mode, a wide range can be illuminated as shown by the dashed arrows in FIG. 65A.
  • FIG. 62 is a schematic perspective view showing a lighting stand as an embodiment of the lighting device.
  • the illumination stand 2200 is generally configured by a light emitting unit 2201, a stand 2202, a main switch 2203, and a power cord 2204.
  • the light emitting unit 2201 is configured from any of the light control devices of the first to twentieth embodiments described above.
  • the illumination stand 2200 is an illumination device that can adjust the light irradiation region by including the light control device of the first to twentieth embodiments described above as the light emitting unit 2201.
  • 66A and 66B show a ceiling light 177 provided with the surface light source device of the above embodiment.
  • this ceiling light 177 by setting the surface light source device in the high directivity mode, it is possible to illuminate a narrow range as shown in FIG. 66A.
  • the illuminating device may be configured with only the light source unit described above, or the illuminating device may be configured with a surface light source device.
  • the light source unit or the surface light source device is used as a lighting device, high directivity is not required as compared with the case of using it as a display device. Therefore, a larger light source can be used to increase the light output.
  • the ceiling light of this embodiment may have the form shown in FIG. FIG. 61 is a schematic perspective view showing a ceiling light as one embodiment of a lighting device.
  • the ceiling light 2190 includes a light emitting unit 2191, a hanging line 2192, and a power cord 2193.
  • the light emitting unit 2191 is composed of any of the light control devices of the first to twentieth embodiments described above.
  • the ceiling light 2190 is an illuminating device that can adjust the region irradiated with light by including the light control device of the first to twentieth embodiments described above as the light emitting unit 2191.
  • the concave mirror and the lens have a parabolic surface.
  • the shape of the concave mirror or lens that can be used in the above embodiment is not necessarily limited to a parabolic surface, but may be a conical curved surface as a concept including a paraboloid.
  • a curve indicating the shape of a cross section passing through the apex of the conical curved surface is called a quadratic curve.
  • a quadratic curve is a curve obtained from a cross section obtained by cutting a cone at an arbitrary plane.
  • the quadratic curve can be expressed by the following equations (1) and (2).
  • the shape of the quadratic curve changes depending on the value of the conic coefficient k in the equations (1) and (2).
  • the region where the light from the LED reaches may be at least a conical curved surface, and the region where the light from the LED does not reach may be, for example, a flat surface.
  • each component of the surface light source device exemplified in the above embodiment can be appropriately changed.
  • various materials can be used for members such as a light guide, a concave mirror, and a wedge-shaped light guide rod, but it is desirable to use a material having high heat resistance for the members in contact with these light sources.
  • Some embodiments of the present invention can be used in various display devices such as liquid crystal display devices, organic electroluminescence display devices, plasma displays, or surface light source devices used in these display devices. It can be used as a light control device that enlarges the angle. Or it can utilize for various illuminating devices, such as an illuminating device which can adjust the area
  • High directivity light source section (first light source section), 14, 114a, 138, 152, 160 ... Wide-angle light source (second light source), 115 ... Second LED (second light-emitting element), 119 ... Prism structure, 139 ... Wedge-shaped light guide rod (angle) (Distribution conversion member), 146... Light guide rod (angle distribution conversion member), 153... Light scattering member (angle distribution conversion member), 161 .. collimating lens (angle distribution conversion member), 165... Liquid crystal display device (display device) 166, 2184 ... Backlight (surface light source device), 168 ... Liquid crystal panel, 175, 176 ... Desk lamp (illumination device), 177, 2190 ...
  • Ceiling light (illumination device), 210, 250, 260, 270, 280, 2140, 2150, 2160, 2170 ... light control device, 213 ... scattering liquid crystal cell, 214, 264, 273, 292, 2112, 2133, 2143, 2153 2163: Reflection mirror, 215, 265, 274, 291, 2111, 1322, 2144, 2154, 2165, 2174 ... Lens, 221 ... Polymer dispersed liquid crystal, 222, 223 ... Transparent conductive substrate, 224, 226 ... Transparent substrate, 225 , 227 ... transparent conductive film, 231,241 ... liquid crystal, 232,243 ... random polymer, 243 ... liquid crystal polymer, 253 ...
  • liquid crystal lens 254 ... first transparent substrate, 255 ... second transparent substrate, 256 ... first transparent electrode 257 ... second transparent electrode, 258 ... insulating spacer, 259 ... liquid crystal layer, 263 ... scatterer, 275 ... gel, 276 ... scattering pattern, 277,278 ... reflecting plate, 283,2166 ... prism, 285,293, 2163 ... scattering liquid crystal cell, 2113 ... projection, 2173 ... electrochromic mirror, 2175 ... anti Projection means, 2180 ... display device, 2181 ... liquid crystal cell, 2182, 2183 ... polarizing plate, 2192 ... hanging line, 2193 ... power cord, 2200 ... lighting stand, 2202 ... stand, 2203 ... main switch, 2204 ... power cord.

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Abstract

In the present invention, a surface light source device is provided with the following: a first light source unit that has a first light-emitting element and that emits the light from the first light-emitting element; a second light source unit that has a second light-emitting element and that emits the light from the second light-emitting element at an angular distribution wider than that of the light emitted from the first light source; and a light guide that causes the light emitted from the first light source and the light emitted from the second light source to enter from an end face and be emitted from a main surface. The first and second light source units are disposed on one of a plurality of end faces of the light guide, and can be controlled independently to be turned on and off.

Description

面光源装置、調光装置およびそれを用いた表示装置、照明装置Surface light source device, light control device, display device using the same, and lighting device
　本発明は、面光源装置、調光装置およびそれを用いた表示装置、照明装置に関する。
　本願は、２０１１年１２月５日に、日本に出願された特願２０１１－２６６１７２号及び２０１１年１２月２２日に、日本に出願された特願２０１１－２８１４７８号に基づき優先権を主張し、その内容をここに援用する。 The present invention relates to a surface light source device, a light control device, a display device using the same, and an illumination device.
This application claims priority based on Japanese Patent Application No. 2011-266172 filed in Japan on December 5, 2011 and Japanese Patent Application No. 2011-281478 filed in Japan on December 22, 2011. The contents are incorporated here.
　表示装置の一例として、面光源装置から射出される光を利用して表示を行う透過型液晶表示装置が知られている。この種の液晶表示装置は、液晶パネルと、液晶パネルの背面側に配置された面光源装置と、を有している。従来の面光源装置は、発光ダイオード（Ｌｉｇｈｔ　Ｅｍｉｔｔｉｎｇ　Ｄｉｏｄｅ, 以下、ＬＥＤと略記する）等の光源と、導光板と、を備えている。この面光源装置では、光源から射出された光を導光板の内部で伝播させ、導光板の全面から射出させる。以下、本明細書では、表示パネルの背面側に設けられる面光源装置のことをバックライトと記す場合もある。 As an example of a display device, a transmissive liquid crystal display device that performs display using light emitted from a surface light source device is known. This type of liquid crystal display device has a liquid crystal panel and a surface light source device disposed on the back side of the liquid crystal panel. A conventional surface light source device includes a light source such as a light emitting diode (hereinafter abbreviated as LED) and a light guide plate. In this surface light source device, the light emitted from the light source is propagated inside the light guide plate and emitted from the entire surface of the light guide plate. Hereinafter, in this specification, the surface light source device provided on the back side of the display panel may be referred to as a backlight.
　指向性が異なる射出光を得るための面光源装置が提案されている（下記の特許文献１～３参照）。 Surface light source devices for obtaining emitted light with different directivities have been proposed (see Patent Documents 1 to 3 below).
　異なる指向特性の出射光を得るための照明装置として、光源からの光を導光体の側方から入射させ、導光体の一方の主面から指向性を有する光を出射する第１照明装置と、光源からの光を拡散部材に入射させて拡散した光束を出射する第２照明装置とが積層された２層構造の照明装置が知られている（例えば、特許文献１参照）。第１照明装置は、高指向性の出射光を得るためのエッジライト型の照明装置であり、第２照明装置は、拡散光を得るための直下型の照明装置である。これら２つの照明装置を切り替えて操作することにより、高指向性（狭視野角）の光および拡散（広視野角）の光を得ることができる。 As a lighting device for obtaining outgoing light having different directivity characteristics, a first lighting device that makes light from a light source incident from the side of a light guide and emits light having directivity from one main surface of the light guide There is known a lighting device having a two-layer structure in which a light from a light source is incident on a diffusing member and a second lighting device that emits a diffused light beam is laminated (see, for example, Patent Document 1). The first illumination device is an edge light type illumination device for obtaining highly directional emitted light, and the second illumination device is a direct illumination device for obtaining diffused light. By switching and operating these two illumination devices, light with high directivity (narrow viewing angle) and light with diffusion (wide viewing angle) can be obtained.
　特許文献１には、射出光の指向性が互いに異なる第１照明装置と第２照明装置とを導光板の厚さ方向に積層した照明装置が開示されている。
　特許文献２には、同心円状に配置された複数のプリズムを備えた導光板と、導光板の前記同心円の中心に配置された第１光源と、導光板の前記同心円の中心から外れた位置に配置された第２光源と、を備えた照明装置が開示されている。
　特許文献３には、導光板と、導光板の第１の端面に光を入射させる第１の光源と、導光板の前記第１の端面と隣り合う第２の端面に光を入射させる第２の光源と、を備え、前記導光板に、射出光の指向性を調整する特性調整部が各光源に対応して設けられた照明装置が開示されている。 Patent Document 1 discloses an illumination device in which a first illumination device and a second illumination device having different directivities of emitted light are stacked in the thickness direction of a light guide plate.
In Patent Document 2, a light guide plate including a plurality of prisms arranged concentrically, a first light source arranged at the center of the concentric circle of the light guide plate, and a position off the center of the concentric circle of the light guide plate. An illumination device including a second light source arranged is disclosed.
In Patent Document 3, a light guide plate, a first light source that makes light incident on the first end surface of the light guide plate, and a second light that makes light incident on a second end surface adjacent to the first end surface of the light guide plate are disclosed. There is disclosed an illuminating device in which a characteristic adjusting unit for adjusting directivity of emitted light is provided on the light guide plate corresponding to each light source.
特開２００８－３００２０６号公報JP 2008-300206 A 特許第４２７４９２１号公報Japanese Patent No. 4274921 特開２００８－２６９８６５号公報JP 2008-269865 A
　特許文献１の照明装置は、第１照明装置と第２照明装置の２組の照明装置が積層された構成を有しているため、部品点数が多い、製造コストが高騰する、照明装置全体の厚さが厚くなる、などの問題がある。また、大面積化するためには、拡散用の光源を多数設ける必要があるため、製造コストが高くなるという問題があった。
　特許文献２の照明装置では、所定の面積の導光板に対して複数のプリズムと２種類の光源の位置関係が決まるため、導光板を大型化するのが難しい、という問題がある。また、いずれの光源を点灯させるかにより導光板内での光の進行方向が変わるため、光源の切り替え前後で輝度を均一に保つのが難しい、という問題がある。また、光の指向性を大きく変えることが難しい、という問題がある。
　特許文献３の照明装置では、特許文献２の照明装置と同様、いずれの光源を点灯させるかにより導光板内での光の進行方向が変わるため、光源の切り替え前後で輝度を均一に保つのが難しい、という問題がある。 Since the lighting device of Patent Document 1 has a configuration in which two sets of lighting devices, a first lighting device and a second lighting device, are stacked, the number of parts is large and the manufacturing cost is increased. There are problems such as thickening. Further, in order to increase the area, it is necessary to provide a large number of light sources for diffusion, and thus there is a problem that the manufacturing cost increases.
The illumination device of Patent Document 2 has a problem that it is difficult to increase the size of the light guide plate because the positional relationship between the plurality of prisms and the two types of light sources is determined with respect to the light guide plate having a predetermined area. Further, since the traveling direction of light in the light guide plate changes depending on which light source is turned on, there is a problem that it is difficult to keep the luminance uniform before and after switching the light source. Another problem is that it is difficult to change the directivity of light.
In the illuminating device of Patent Document 3, as in the illuminating device of Patent Document 2, since the traveling direction of light in the light guide plate changes depending on which light source is turned on, the luminance is kept uniform before and after switching of the light source. There is a problem that it is difficult.
　本発明のいくつかの態様は、上記の課題を解決するためになされたものであって、指向性の切り替えが可能であり、部品点数や製造コストの増大を招くことなく、装置全体の厚さが厚くなることのない面光源装置を提供することを目的とする。また、本発明のいくつかの態様は、指向性の切り替えが可能であり、指向性の切り替え前後で輝度を均一に保つことができる面光源装置を提供することを目的とする。また、本発明のいくつかの態様は、この種の面光源装置を備えた表示装置および照明装置を提供することを目的とする。 Some aspects of the present invention have been made in order to solve the above-described problem, and can change the directivity, and the thickness of the entire apparatus without causing an increase in the number of parts or manufacturing cost. An object of the present invention is to provide a surface light source device that does not become thick. It is another object of some aspects of the present invention to provide a surface light source device that can switch directivity and can maintain uniform luminance before and after switching directivity. Another object of some aspects of the present invention is to provide a display device and an illumination device provided with this type of surface light source device.
本発明のいくつかの態様は、上記事情に鑑みてなされたものであって、出射光を、指向性を有する光と散乱光とに切り替え可能な調光装置を提供することを目的とする。 Some aspects of the present invention have been made in view of the above circumstances, and an object thereof is to provide a light control device capable of switching emitted light between light having directivity and scattered light.
　上記の目的を達成するために、本発明の一態様における面光源装置は、第１の発光素子を有し、前記第１の発光素子からの光を射出する第１の光源部と、第２の発光素子を有し、前記第２の発光素子からの光を、前記第１の光源部から射出される光の角度分布よりも広い角度分布を有する光として射出する第２の光源部と、前記第１の光源部から射出された光および前記第２の光源部から射出された光を端面から入射させ、主面から射出させる導光体と、を備え、前記第１の光源部と前記第２の光源部とは、前記導光体の複数の端面のうちの一つの端面に設けられ、点灯／消灯を各々独立して制御可能とされる。 In order to achieve the above object, a surface light source device according to an aspect of the present invention includes a first light source unit that includes a first light emitting element, and emits light from the first light emitting element. A second light source unit that emits light from the second light emitting element as light having an angular distribution wider than the angular distribution of light emitted from the first light source unit, A light guide that causes light emitted from the first light source unit and light emitted from the second light source unit to be incident from an end surface and to be emitted from a main surface, and includes the first light source unit and the light source The second light source unit is provided on one end surface of the plurality of end surfaces of the light guide, and lighting / extinguishing can be independently controlled.
　本発明の一態様における面光源装置において、前記第１の光源部および前記第２の光源部のいずれか一方は、前記第１の光源部から射出される光の角度分布と前記第２の光源部から射出される光の角度分布とを異ならせるための角度分布変換部材を備えてもよい。 In the surface light source device according to one aspect of the present invention, any one of the first light source unit and the second light source unit includes an angular distribution of light emitted from the first light source unit and the second light source. You may provide the angle distribution conversion member for making different the angle distribution of the light inject | emitted from a part.
　本発明の一態様における面光源装置において、前記第１の光源部が、前記角度分布変換部材として、前記第１の発光素子から射出された光を反射する凹面ミラーを備え、前記凹面ミラーは、前記導光体の主面に平行な平面で切断したときの断面形状が、焦点を有する曲線形状を少なくとも一部に有し、前記第１の発光素子は、前記第１の発光素子の発光面上に前記焦点が位置するように配置され、前記第１の発光素子からの光が、前記凹面ミラーで反射して前記導光体に入射してもよい。 In the surface light source device according to the aspect of the present invention, the first light source unit includes a concave mirror that reflects light emitted from the first light emitting element as the angle distribution conversion member, and the concave mirror includes: The cross-sectional shape when cut along a plane parallel to the main surface of the light guide body has at least part of a curved shape having a focal point, and the first light emitting element is a light emitting surface of the first light emitting element. The light source from the first light emitting element may be reflected by the concave mirror and incident on the light guide.
　本発明の一態様における面光源装置において、前記第２の発光素子が、前記第１の光源部から射出される光の角度分布よりも広い角度分布を有する光を射出し、前記第２の発光素子から射出された光が、前記凹面ミラーを介することなく前記導光体に入射してもよい。 In the surface light source device according to one embodiment of the present invention, the second light emitting element emits light having an angular distribution wider than the angular distribution of light emitted from the first light source unit, and the second light emission. The light emitted from the element may enter the light guide without passing through the concave mirror.
　本発明の一態様における面光源装置において、前記第１の発光素子と前記第２の発光素子とが、互いの発光面と反対側の面同士が対向するように配置されてもよい。 In the surface light source device according to an aspect of the present invention, the first light emitting element and the second light emitting element may be arranged such that surfaces opposite to each other's light emitting surface face each other.
　本発明の一態様における面光源装置において、前記第１の光源部が、前記導光体の一つの端面に沿って配列された複数の前記発光素子および複数の前記凹面ミラーを備え、前記第２の発光素子は、隣り合う凹面ミラー同士の境界に沿って配置されてもよい。 In the surface light source device according to an aspect of the present invention, the first light source unit includes the plurality of light emitting elements and the plurality of concave mirrors arranged along one end surface of the light guide, The light emitting elements may be arranged along the boundary between adjacent concave mirrors.
　本発明の一態様における面光源装置において、前記凹面ミラーが、前記導光体の主面に垂直な平面で切断したときの断面形状が直線形状であって、前記導光体の主面に垂直な方向には曲率を持たず、前記第１の発光素子が、前記導光体の主面に垂直な方向に沿って配置され、前記第２の発光素子が、前記導光体の主面に平行な方向に沿って配置されてもよい。 In the surface light source device according to an aspect of the present invention, the concave mirror has a linear shape when the concave mirror is cut along a plane perpendicular to the main surface of the light guide, and is perpendicular to the main surface of the light guide. The first light emitting element is disposed along a direction perpendicular to the main surface of the light guide, and the second light emitting element is formed on the main surface of the light guide. You may arrange | position along a parallel direction.
　本発明の一態様における面光源装置において、前記第１の光源部が、前記凹面ミラーの窪みに配置された凸レンズを備え、前記凸レンズの焦点の位置が前記凹面ミラーの焦点の位置と略一致していてもよい。 In the surface light source device according to one aspect of the present invention, the first light source unit includes a convex lens disposed in a recess of the concave mirror, and the focal position of the convex lens substantially coincides with the focal position of the concave mirror. It may be.
　本発明の一態様における面光源装置において、前記凹面ミラーが、前記凸レンズの凸面に形成された金属膜もしくは誘電体多層膜で構成されていいてもよい。 In the surface light source device according to one aspect of the present invention, the concave mirror may be formed of a metal film or a dielectric multilayer film formed on a convex surface of the convex lens.
　本発明の一態様における面光源装置において、前記第１の光源部が、前記角度分布変換部材として、前記第１の発光素子から射出された光を反射する反射面を有する反射素子を備え、前記反射素子が、前記導光体の前記一つの端面に対して一定の角度で傾斜した前記反射面と、前記導光体の前記一つの端面に対向する光射出面と、を有し、前記第１の発光素子が、前記反射素子の一つの端面に配置され、前記第１の発光素子からの光が、前記反射面で反射して前記導光体に入射してもよい。 In the surface light source device according to one aspect of the present invention, the first light source unit includes, as the angle distribution conversion member, a reflective element having a reflective surface that reflects light emitted from the first light emitting element, The reflective element includes the reflective surface inclined at a constant angle with respect to the one end surface of the light guide, and a light exit surface facing the one end surface of the light guide, One light emitting element may be disposed on one end face of the reflecting element, and light from the first light emitting element may be reflected by the reflecting surface and incident on the light guide.
　本発明の一態様における面光源装置において、前記第２の発光素子が、前記第１の光源部から射出される光の角度分布よりも広い角度分布を有する光を射出し、前記第２の発光素子から射出された光が、前記反射素子を介することなく前記導光体に入射してもよい。 In the surface light source device according to one embodiment of the present invention, the second light emitting element emits light having an angular distribution wider than the angular distribution of light emitted from the first light source unit, and the second light emission. The light emitted from the element may enter the light guide without passing through the reflective element.
　本発明の一態様における面光源装置において、前記反射素子が、前記導光体の前記一つの端面に対して複数個設けられてもよい。 In the surface light source device according to an aspect of the present invention, a plurality of the reflective elements may be provided for the one end surface of the light guide.
　本発明の他の態様における面光源装置は、前記反射素子が、前記第１の発光素子が配置された端面に近い側から遠い側に向けて厚みが薄くなる楔形状を有し、前記光射出面と対向する端面全体が前記反射面であってもよい。 In the surface light source device according to another aspect of the present invention, the reflective element has a wedge shape whose thickness decreases from a side closer to an end face on which the first light emitting element is disposed to a side farther from the end face. The entire end surface facing the surface may be the reflecting surface.
　本発明の一態様における面光源装置は、前記反射素子が、前記光射出面と対向する面に複数のプリズム構造体を有し、前記プリズム構造体の一つの傾斜面が前記反射面であってもよい。 In the surface light source device according to one aspect of the present invention, the reflection element has a plurality of prism structures on a surface facing the light emission surface, and one inclined surface of the prism structure is the reflection surface. Also good.
　本発明の一態様における面光源装置は、前記第２の光源部が、前記角度分布変換部材として、前記第２の発光素子から射出された光を散乱させる光散乱部材を備え、前記第２の発光素子から射出された光が、前記光散乱部材を介して前記導光体に入射してもよい。 In the surface light source device according to an aspect of the present invention, the second light source unit includes a light scattering member that scatters light emitted from the second light emitting element as the angle distribution conversion member, Light emitted from the light emitting element may enter the light guide through the light scattering member.
　本発明の一態様における面光源装置において、前記第１の光源部が、前記角度分布変換部材として、前記第１の発光素子から射出された光を略平行化するレンズを備え、前記第１の発光素子から射出された光が、前記レンズを介して前記導光体に入射してもよい。 In the surface light source device according to an aspect of the present invention, the first light source unit includes a lens that substantially parallelizes light emitted from the first light emitting element as the angle distribution conversion member. The light emitted from the light emitting element may enter the light guide through the lens.
　本発明の一態様における面光源装置において、前記導光体が、光の伝播方向において前記主面に対して所定の傾斜角をなす反射面を有してもよい。 In the surface light source device according to an aspect of the present invention, the light guide may have a reflecting surface that forms a predetermined inclination angle with respect to the main surface in the light propagation direction.
　本発明の一態様における面光源装置において、前記導光体が、前記一つの端面に近い側から遠い側に向けて厚みが薄くなる楔形状を有し、前記主面と対向する面全体が前記反射面であってもよい。 In the surface light source device according to one aspect of the present invention, the light guide has a wedge shape that decreases in thickness toward a side farther from the side closer to the one end surface, and the entire surface facing the main surface is the It may be a reflective surface.
　本発明の一態様における面光源装置において、前記導光体が、前記主面と対向する面に複数のプリズム構造体を有し、前記プリズム構造体の一つの傾斜面が前記反射面であってもよい。 In the surface light source device according to one aspect of the present invention, the light guide has a plurality of prism structures on a surface facing the main surface, and one inclined surface of the prism structure is the reflection surface. Also good.
　本発明の一態様における面光源装置は、さらに前記導光体の主面から射出された光の進行方向を、前記主面の法線により近い方向に変更するための方向変更用部材を備えてもよい。 The surface light source device according to an aspect of the present invention further includes a direction changing member for changing the traveling direction of the light emitted from the main surface of the light guide to a direction closer to the normal line of the main surface. Also good.
　本発明の他の態様における表示装置は、前記面光源装置と、前記面光源装置から射出される光を用いて表示を行う表示素子と、を備える。 A display device according to another aspect of the present invention includes the surface light source device and a display element that performs display using light emitted from the surface light source device.
　本発明のさらに他の態様における照明装置は、前記面光源装置を備える。 An illumination device in still another aspect of the present invention includes the surface light source device.
　本発明のさらに他の態様における照明装置は、前記面光源装置の前記第１の光源部および前記第２の光源部を備えてもよい。 The illumination device according to still another aspect of the present invention may include the first light source unit and the second light source unit of the surface light source device.
　本発明のさらに他の態様における調光源装置は、光源部と、前記光源部を端部に持つ導光体と、前記光源部と前記導光体との間または前記光源部における前記導光体の端部とは反対側に配設された配光変換素子と、を備え、前記配光変換素子の配光特性が可変である。 The modulated light source device according to still another aspect of the present invention includes a light source unit, a light guide body having the light source unit at an end thereof, and the light guide body between the light source unit and the light guide body or in the light source unit. A light distribution conversion element disposed on a side opposite to the end of the light distribution conversion element, and the light distribution characteristic of the light distribution conversion element is variable.
　本発明のさらに他の態様における調光装置において、前記配光変換素子は、前記光源部の前記導光体の一端面と対向する面とは反対の面側に設けられ、前記光源部からの光を反射する反射面を有する反射ミラーを備えたパラボラミラー形状のレンズであってもよい。 In the light control device according to yet another aspect of the present invention, the light distribution conversion element is provided on a surface of the light source unit opposite to a surface facing the one end surface of the light guide, and from the light source unit. It may be a parabolic mirror-shaped lens provided with a reflecting mirror having a reflecting surface for reflecting light.
　本発明のさらに他の態様における調光装置において、前記レンズは、中空構造をなしていてもよい。 In the light control device according to still another aspect of the present invention, the lens may have a hollow structure.
　本発明のさらに他の態様における調光装置において、前記レンズ内は、樹脂が充填されていてもよい。 In the light control device according to still another aspect of the present invention, the lens may be filled with resin.
　本発明のさらに他の態様における調光装置において、前記反射ミラーは、金属の蒸着膜からなってもよい。 In the light control device according to still another aspect of the present invention, the reflection mirror may be made of a metal vapor deposition film.
　本発明のさらに他の態様における調光装置において、前記反射ミラーは、誘電体ミラーからなってもよい。 In the light control device according to still another aspect of the present invention, the reflection mirror may be a dielectric mirror.
　本発明のさらに他の態様における調光装置において、前記反射ミラーの反射面に、散乱液晶セルが設けられてもよい。 In the light control device according to still another aspect of the present invention, a scattering liquid crystal cell may be provided on the reflection surface of the reflection mirror.
　本発明のさらに他の態様における調光装置において、前記レンズには、微小電子機械システム制御により、前記光源部側に出し入れ可能な複数の突起が設けられてもよい。 In the light control device according to still another aspect of the present invention, the lens may be provided with a plurality of protrusions that can be taken in and out of the light source unit under the control of a micro electro mechanical system.
　本発明のさらに他の態様における調光装置において、前記反射ミラーは、エレクトロクロミックミラーからなり、前記エレクトロクロミックミラーの前記光源部と対向する面とは反対の面側に、前記エレクトロクロミックミラーを透過した光を反射する反射手段が設けられてもよい。 In the light control device according to still another aspect of the present invention, the reflection mirror is an electrochromic mirror, and is transmitted through the electrochromic mirror on a surface opposite to the surface facing the light source part of the electrochromic mirror. Reflecting means for reflecting the reflected light may be provided.
　本発明のさらに他の態様における調光装置において、前記配光変換素子は、前記光源部と前記導光体の一端面との間に設けられてもよい。 In the light control device according to still another aspect of the present invention, the light distribution conversion element may be provided between the light source unit and one end surface of the light guide.
　本発明のさらに他の態様における調光装置において、前記配光変換素子は、散乱液晶セルであってもよい。 In the light control device according to still another aspect of the present invention, the light distribution conversion element may be a scattering liquid crystal cell.
　本発明のさらに他の態様における調光装置において、前記配光変換素子は、液晶レンズであってもよい。 In the light control device according to still another aspect of the present invention, the light distribution conversion element may be a liquid crystal lens.
　本発明のさらに他の態様における調光装置において、前記配光変換素子は、前記光源部と前記導光体の一端面との間に挿抜可能な散乱体であってもよい。 In the light control device according to still another aspect of the present invention, the light distribution conversion element may be a scatterer that can be inserted and removed between the light source unit and one end surface of the light guide.
　本発明のさらに他の態様における調光装置において、前記配光変換素子は、前記導光体の一端面に対向して配設された入光部と、前記入光部と前記一端面とを光学接着が可能なゲルと、前記一端面に設けられた散乱パターンと、前記ゲルと前記一端面との境界部を、前記導光体の厚さ方向から挟持する一対の反射板と、を備えてなってもよい。 In the light control device according to still another aspect of the present invention, the light distribution conversion element includes a light incident part disposed to face one end face of the light guide, the light incident part, and the one end face. A gel capable of optical bonding; a scattering pattern provided on the one end face; and a pair of reflectors that sandwich a boundary between the gel and the one end face from the thickness direction of the light guide. May be.
　本発明のさらに他の態様における調光装置において、前記配光変換素子は、楔形状の導光体と、前記導光体に対向し、光の入射面が鋸刃形状をなすプリズムとからなってもよい。 In the light control device according to still another aspect of the present invention, the light distribution conversion element includes a wedge-shaped light guide and a prism that faces the light guide and has a light incident surface having a saw blade shape. May be.
　本発明のさらに他の態様における調光装置において、前記導光体は、楔形状であってもよい。 In the light control device according to still another aspect of the present invention, the light guide may have a wedge shape.
　本発明のさらに他の態様における表示装置は、前記の調光装置を備える。 A display device according to still another aspect of the present invention includes the light control device.
　本発明のさらに他の態様における照明装置は、前記の調光装置を備える。 The illuminating device in the further another aspect of this invention is equipped with the said light control apparatus.
　本発明のいくつかの態様によれば、指向性の切り替えが可能であり、部品点数や製造コストの増大を招くことなく、装置全体の厚さが厚くなることのない面光源装置が実現できる。本発明によれば、指向性の切り替えが可能であり、指向性の切り替え前後で輝度を均一に保つことができる面光源装置が実現できる。本発明によれば、上記の効果を有する面光源装置を備えた表示装置および照明装置が実現できる。
　本発明のいくつかの態様によれば、光源部からの光に指向性を付与する配光変換素子を用いることにより、調光装置から出射する光を、指向性を有する光と散乱光とに切り替えることができる。 According to some aspects of the present invention, it is possible to realize a surface light source device that can switch directivity, does not increase the number of parts and the manufacturing cost, and does not increase the thickness of the entire device. According to the present invention, it is possible to realize a surface light source device that can switch directivity and can maintain a uniform luminance before and after switching directivity. According to the present invention, it is possible to realize a display device and an illumination device including the surface light source device having the above-described effects.
According to some aspects of the present invention, by using a light distribution conversion element that imparts directivity to light from the light source unit, light emitted from the light control device is converted into light having directivity and scattered light. Can be switched.
本発明の第１実施形態の面光源装置を示す斜視図である。It is a perspective view which shows the surface light source device of 1st Embodiment of this invention. 図１のＡ１－Ａ１’線に沿う断面図である。FIG. 2 is a cross-sectional view taken along the line A1-A1 'of FIG. 本実施形態の面光源装置における第１の光源部および第２の光源部を示す斜視図である。It is a perspective view which shows the 1st light source part and the 2nd light source part in the surface light source device of this embodiment. 図３のＢ１－Ｂ１’線に沿う断面図である。FIG. 4 is a cross-sectional view taken along line B1-B1 'of FIG. 図３のＣ１－Ｃ１’線に沿う断面図である。FIG. 4 is a cross-sectional view taken along line C1-C1 ′ of FIG. 広角モードにおける光の作用を示す図である。It is a figure which shows the effect | action of the light in a wide angle mode. 広角モードにおける光の作用を示す図である。It is a figure which shows the effect | action of the light in a wide angle mode. 高指向性モードにおける光の作用を説明するための図である。It is a figure for demonstrating the effect | action of the light in a high directivity mode. 広角モード、高指向性モードのそれぞれにおけるｘ軸方向の輝度分布を示す図である。It is a figure which shows the luminance distribution of the x-axis direction in each of a wide angle mode and a high directivity mode. 楔状導光板によるｙ軸方向の輝度分布を示す図である。It is a figure which shows the luminance distribution of the y-axis direction by a wedge-shaped light-guide plate. 第１実施形態の第１変形例の面光源装置を示す断面図である。It is sectional drawing which shows the surface light source device of the 1st modification of 1st Embodiment. 第１実施形態の第２変形例の面光源装置を示す断面図である。It is sectional drawing which shows the surface light source device of the 2nd modification of 1st Embodiment. 本発明の第２実施形態の面光源装置における光源部を示す斜視図である。It is a perspective view which shows the light source part in the surface light source device of 2nd Embodiment of this invention. 広角モード、高指向性モードのそれぞれにおける光の作用を示す図である。It is a figure which shows the effect | action of the light in each of a wide angle mode and a high directivity mode. 第２実施形態の第１変形例の面光源装置を示す断面図である。It is sectional drawing which shows the surface light source device of the 1st modification of 2nd Embodiment. 本発明の第３実施形態の面光源装置における光源部を示す斜視図である。It is a perspective view which shows the light source part in the surface light source device of 3rd Embodiment of this invention. 本実施形態の面光源装置を示す側面図である。It is a side view which shows the surface light source device of this embodiment. 本実施形態の面光源装置を示す平面図である。It is a top view which shows the surface light source device of this embodiment. 第３実施形態の第１変形例の面光源装置における光源部を示す斜視図である。It is a perspective view which shows the light source part in the surface light source device of the 1st modification of 3rd Embodiment. 本発明の第４実施形態の面光源装置における光源部を示す斜視図である。It is a perspective view which shows the light source part in the surface light source device of 4th Embodiment of this invention. 本実施形態の面光源装置を示す平面図である。It is a top view which shows the surface light source device of this embodiment. 本発明の第５実施形態の面光源装置を示す分解斜視図である。It is a disassembled perspective view which shows the surface light source device of 5th Embodiment of this invention. 本実施形態の面光源装置を示す平面図である。It is a top view which shows the surface light source device of this embodiment. 本実施形態の面光源装置を示す側面図である。It is a side view which shows the surface light source device of this embodiment. 本実施形態の面光源装置における楔形導光棒の作用を説明するための図である。It is a figure for demonstrating the effect | action of the wedge-shaped light guide rod in the surface light source device of this embodiment. 本実施形態の面光源装置の効果を説明するための図である。It is a figure for demonstrating the effect of the surface light source device of this embodiment. 第５実施形態の第１変形例の面光源装置を示す平面図である。It is a top view which shows the surface light source device of the 1st modification of 5th Embodiment. 第５実施形態の第２変形例の面光源装置における導光棒を示す平面図である。It is a top view which shows the light guide bar in the surface light source device of the 2nd modification of 5th Embodiment. 本発明の第６実施形態の面光源装置を示す分解斜視図である。It is a disassembled perspective view which shows the surface light source device of 6th Embodiment of this invention. 本実施形態の面光源装置を示す平面図である。It is a top view which shows the surface light source device of this embodiment. 本実施形態の面光源装置を示す側面図である。It is a side view which shows the surface light source device of this embodiment. 第６実施形態の第１変形例の面光源装置を示す平面図である。It is a top view which shows the surface light source device of the 1st modification of 6th Embodiment. 本発明の第７実施形態の面光源装置を示す平面図である。It is a top view which shows the surface light source device of 7th Embodiment of this invention. 本実施形態の面光源装置を示す側面図である。It is a side view which shows the surface light source device of this embodiment. 本実施形態の面光源装置を示す平面図である。It is a top view which shows the surface light source device of this embodiment. 図２８ＡのＡ１－Ａ１’線に沿う断面図である。It is sectional drawing which follows the A1-A1 'line | wire of FIG. 28A. 本実施形態の面光源装置における照度分布のシミュレーション結果を示す図である。It is a figure which shows the simulation result of the illumination intensity distribution in the surface light source device of this embodiment. 本実施形態の面光源装置における照度分布のシミュレーション結果を示す図である。It is a figure which shows the simulation result of the illumination intensity distribution in the surface light source device of this embodiment. 本実施形態の面光源装置における照度分布のシミュレーション結果を示す図である。It is a figure which shows the simulation result of the illumination intensity distribution in the surface light source device of this embodiment. 比較例の面光源装置における照度分布のシミュレーション結果を示す図である。It is a figure which shows the simulation result of the illumination intensity distribution in the surface light source device of a comparative example. 比較例の面光源装置における照度分布のシミュレーション結果を示す図である。It is a figure which shows the simulation result of the illumination intensity distribution in the surface light source device of a comparative example. 本発明の表示装置の一構成例である液晶表示装置の断面図である。It is sectional drawing of the liquid crystal display device which is one structural example of the display apparatus of this invention. 調光装置の第９実施形態を示す概略平面図である。It is a schematic plan view which shows 9th Embodiment of a light modulation apparatus. 調光装置の第９実施形態を示す概略図３２ＡのＡ－Ａ線に沿う断面図である。FIG. 32C is a cross-sectional view taken along line AA of FIG. 32A, showing a ninth embodiment of the light control device. 散乱液晶セルの一実施形態を示す概略断面図である。It is a schematic sectional drawing which shows one Embodiment of a scattering liquid crystal cell. 散乱液晶セルを構成する高分子分散液晶としてノーマルモード高分子分散液晶を用いた場合について説明する図である。It is a figure explaining the case where a normal mode polymer dispersion liquid crystal is used as a polymer dispersion liquid crystal which comprises a scattering liquid crystal cell. 散乱液晶セルを構成する高分子分散液晶としてノーマルモード高分子分散液晶を用いた場合について説明する図である。It is a figure explaining the case where a normal mode polymer dispersion liquid crystal is used as a polymer dispersion liquid crystal which comprises a scattering liquid crystal cell. 散乱液晶セルを構成する高分子分散液晶としてリバースモード高分子分散液晶を用いた場合について説明する図である。It is a figure explaining the case where a reverse mode polymer dispersion liquid crystal is used as a polymer dispersion liquid crystal which comprises a scattering liquid crystal cell. 散乱液晶セルを構成する高分子分散液晶としてリバースモード高分子分散液晶を用いた場合について説明する図である。It is a figure explaining the case where a reverse mode polymer dispersion liquid crystal is used as a polymer dispersion liquid crystal which comprises a scattering liquid crystal cell. 散乱液晶セルを構成する液晶を配向させて、調光装置を用いた場合を説明する概略平面図である。It is a schematic plan view explaining the case where the liquid crystal which comprises a scattering liquid crystal cell is orientated and a light control apparatus is used. 散乱液晶セルを構成する液晶を配向させて、調光装置を用いた場合を説明する導光体の一端面側から見た正面図である。It is the front view seen from the end surface side of the light guide explaining the case where the liquid crystal which comprises a scattering liquid crystal cell is orientated and a light control apparatus is used. 散乱液晶セルを構成する液晶を配向させずに、調光装置を用いた場合を説明する概略図平面図である。It is the schematic top view explaining the case where a light control apparatus is used, without aligning the liquid crystal which comprises a scattering liquid crystal cell. 散乱液晶セルを構成する液晶を配向させずに、調光装置を用いた場合を説明する導光体の一端面側から見た正面図である。It is the front view seen from the end surface side of the light guide explaining the case where a light control device is used, without aligning the liquid crystal which comprises a scattering liquid crystal cell. 調光装置の第１０実施形態を示す概略側面図である。It is a schematic side view which shows 10th Embodiment of a light modulation apparatus. 図３８Ａの一部を拡大した斜視図である。It is the perspective view which expanded a part of FIG. 38A. 液晶レンズを用いた調光装置の使用方法を説明する概略側面図である。It is a schematic side view explaining the usage method of the light modulation apparatus using a liquid crystal lens. 液晶レンズを用いた調光装置の使用方法を説明する概略側面図である。It is a schematic side view explaining the usage method of the light modulation apparatus using a liquid crystal lens. 調光装置の第１１実施形態を示す概略平面図である。It is a schematic plan view which shows 11th Embodiment of a light modulation apparatus. 図４０ＡのＢ２－Ｂ２線に沿う断面図である。FIG. 40B is a cross-sectional view taken along line B2-B2 of FIG. 40A. 光源部と導光体の一端面との間に、散乱体を挿入していない状態を示す概略図平面図である。It is the schematic top view which shows the state which has not inserted the scatterer between the light source part and the end surface of a light guide. 導光体の一端面側から見た正面図である。It is the front view seen from the one end surface side of a light guide. 図４１ＡのＣ－Ｃ線に沿う断面図である。FIG. 41B is a cross-sectional view taken along the line CC of FIG. 41A. 光源部と導光体の一端面との間に、散乱体を挿入した状態を示す概略図平面図である。It is the schematic top view which shows the state which inserted the scatterer between the light source part and the one end surface of a light guide. 導光体の一端面側から見た正面図である。It is the front view seen from the one end surface side of a light guide. 図４２ＡのＤ－Ｄ線に沿う断面図である。FIG. 42B is a cross-sectional view taken along the line DD of FIG. 42A. 調光装置の第１２実施形態を示す概略断面図である。It is a schematic sectional drawing which shows 12th Embodiment of a light modulation apparatus. 入光部と導光体の一端面との間にゲルを設けた調光装置の使用方法を示す概略断面図である。It is a schematic sectional drawing which shows the usage method of the light modulation apparatus which provided the gel between the light-incidence part and the one end surface of the light guide. 入光部と導光体の一端面との間にゲルを設けた調光装置の使用方法を示す概略断面図である。It is a schematic sectional drawing which shows the usage method of the light modulation apparatus which provided the gel between the light-incidence part and the one end surface of the light guide. 調光装置の第１３実施形態を示す概略図平面図である。It is the schematic plan view which shows 13th Embodiment of a light modulation apparatus. 調光装置の第１３実施形態を示す概略側面図である。It is a schematic side view which shows 13th Embodiment of a light modulation apparatus. 調光装置の第１３実施形態の作用を示す概略平面図である。It is a schematic plan view which shows the effect | action of 13th Embodiment of a light modulation apparatus. 調光装置の第１３実施形態の他の例を示す概略平面図である。It is a schematic plan view which shows the other example of 13th Embodiment of a light modulation apparatus. 調光装置の第１４実施形態を示す概略平面図であり、調光装置を構成するパラボラミラー形状のレンズを示す図である。It is a schematic plan view which shows 14th Embodiment of a light modulation apparatus, and is a figure which shows the parabolic mirror-shaped lens which comprises a light modulation apparatus. 散乱液晶セルを備えたパラボラミラー形状のレンズの作用を示す概略平面図である。It is a schematic plan view which shows the effect | action of the parabolic mirror-shaped lens provided with the scattering liquid crystal cell. 散乱液晶セルを備えたパラボラミラー形状のレンズの作用を示す概略平面図である。It is a schematic plan view which shows the effect | action of the parabolic mirror-shaped lens provided with the scattering liquid crystal cell. 調光装置の第１５実施形態を示す概略平面図であり、調光装置を構成するパラボラミラー形状のレンズを示す図である。It is a schematic plan view which shows 15th Embodiment of a light modulation apparatus, and is a figure which shows the parabolic mirror-shaped lens which comprises a light modulation apparatus. 複数の突起を備えたパラボラミラー形状のレンズの作用を示す概略平面図である。It is a schematic plan view which shows the effect | action of the parabolic mirror-shaped lens provided with the some protrusion. 複数の突起を備えたパラボラミラー形状のレンズの作用を示す概略平面図である。It is a schematic plan view which shows the effect | action of the parabolic mirror-shaped lens provided with the some protrusion. 調光装置の第１６実施形態を示す概略平面図であり、調光装置を構成する光源部およびパラボラミラー形状のレンズを示す図である。It is a schematic plan view which shows 16th Embodiment of a light modulation apparatus, and is a figure which shows the light source part and parabolic mirror-shaped lens which comprise a light modulation apparatus. 調光装置の第１７実施形態を示す概略断面図である。It is a schematic sectional drawing which shows 17th Embodiment of a light modulation apparatus. 調光装置の第１７実施形態の作用を示す概略平面図である。It is a schematic plan view which shows the effect | action of 17th Embodiment of a light modulation apparatus. 調光装置の第１７実施形態の作用を示す概略平面図である。It is a schematic plan view which shows the effect | action of 17th Embodiment of a light modulation apparatus. 調光装置の第１８実施形態を示す概略断面図である。It is a schematic sectional drawing which shows 18th Embodiment of a light modulation apparatus. 調光装置の第１８実施形態の作用を示す概略平面図である。It is a schematic plan view which shows the effect | action of 18th Embodiment of a light modulation apparatus. 調光装置の第１８実施形態の作用を示す概略平面図である。It is a schematic plan view which shows the effect | action of 18th Embodiment of a light modulation apparatus. 調光装置の第１９実施形態を示す概略図平面図である。It is the schematic plan view which shows 19th Embodiment of a light modulation apparatus. 図５７ＡのＥ－Ｅ線に沿う断面図である。FIG. 57B is a cross-sectional view taken along line EE in FIG. 57A. 調光装置の第２０実施形態を示す概略平面図であり、全体図である。It is a schematic plan view which shows 20th Embodiment of a light modulation apparatus, and is a general view. 図５８Ａにおいて破線αで囲んだ領域を拡大した図である。It is the figure which expanded the area | region enclosed with the broken line (alpha) in FIG. 58A. エレクトロクロミックミラーを備えたパラボラミラー形状のレンズの作用を示す概略平面図である。It is a schematic plan view which shows the effect | action of the parabolic mirror-shaped lens provided with the electrochromic mirror. エレクトロクロミックミラーを備えたパラボラミラー形状のレンズの作用を示す概略平面図である。It is a schematic plan view which shows the effect | action of the parabolic mirror-shaped lens provided with the electrochromic mirror. 表示装置の一実施形態を示す概略斜視図である。It is a schematic perspective view which shows one Embodiment of a display apparatus. 照明装置の第一実施形態として、シーリングライトを示す概略斜視図である。It is a schematic perspective view which shows a ceiling light as 1st embodiment of an illuminating device. 照明装置の第二実施形態として、照明スタンドを示す概略斜視図である。It is a schematic perspective view which shows an illumination stand as 2nd embodiment of an illuminating device. 液晶表示装置の正面図である。It is a front view of a liquid crystal display device. 本発明の照明装置の一構成例である電気スタンドを示す図である。It is a figure which shows the table lamp which is one structural example of the illuminating device of this invention. 本発明の照明装置の一構成例である電気スタンドを示す図である。It is a figure which shows the table lamp which is one structural example of the illuminating device of this invention. 本発明の照明装置の一構成例である電気スタンドを示す図である。It is a figure which shows the table lamp which is one structural example of the illuminating device of this invention. 本発明の照明装置の一構成例である電気スタンドを示す図である。It is a figure which shows the table lamp which is one structural example of the illuminating device of this invention. 本発明の照明装置の一構成例であるシーリングライトを示す図である。It is a figure which shows the ceiling light which is one structural example of the illuminating device of this invention. 本発明の照明装置の一構成例であるシーリングライトを示す図である。It is a figure which shows the ceiling light which is one structural example of the illuminating device of this invention.
［第１実施形態］
　以下、本発明の第１実施形態について、図１～図７を用いて説明する。
　本実施形態では、例えば液晶表示装置のバックライトとして用いて好適な面光源装置（調光装置ともいう）の一例を示す。
　図１は、本実施形態の面光源装置を示す斜視図である。図２は、図１のＡ１－Ａ１’線に沿う断面図である。図３は、本実施形態の面光源装置における一つの光源を示す斜視図である。図４Ａは、図３のＢ－Ｂ’線に沿う断面図である。図４Ｂは、図３のＣ－Ｃ’線に沿う断面図である。
　なお、以下に示す実施形態は、発明の趣旨をよりよく理解させるために具体的に説明するものであり、特に指定のない限り、本発明を限定するものではない。
また、以下の説明で用いる図面は、本発明の特徴を分かりやすくするために、便宜上、要部となる部分を拡大して示している場合があり、各構成要素の寸法比率等が実際と同じであるとは限らない。　 [First Embodiment]
Hereinafter, a first embodiment of the present invention will be described with reference to FIGS.
In the present embodiment, an example of a surface light source device (also referred to as a light control device) suitable for use as a backlight of a liquid crystal display device, for example, is shown.
FIG. 1 is a perspective view showing the surface light source device of this embodiment. FIG. 2 is a sectional view taken along line A1-A1 ′ of FIG. FIG. 3 is a perspective view showing one light source in the surface light source device of the present embodiment. 4A is a cross-sectional view taken along line BB ′ of FIG. 4B is a cross-sectional view taken along the line CC ′ of FIG.
The following embodiments are specifically described for better understanding of the gist of the invention, and do not limit the present invention unless otherwise specified.
In addition, in the drawings used in the following description, in order to make the features of the present invention easier to understand, there is a case where a main part is shown in an enlarged manner for the sake of convenience. Not necessarily.
　本実施形態の面光源装置１１は、図１および図２に示すように、光源部１２と、導光体１３と、プリズムシート１４（方向変更用部材）と、から構成されている。導光体１３は、光源部１２から射出された光を端面から入射させ、内部で伝播させる間に主面から射出させる機能を有する。プリズムシート１４は、導光体１３の主面から射出された光の進行方向を、主面の法線により近い方向に変更する機能を有する。なお、光源部１２の詳細な構成は後述する。 1 and 2, the surface light source device 11 of the present embodiment includes a light source unit 12, a light guide 13, and a prism sheet 14 (direction changing member). The light guide 13 has a function of causing light emitted from the light source unit 12 to enter from the end face and to be emitted from the main surface while propagating inside. The prism sheet 14 has a function of changing the traveling direction of the light emitted from the main surface of the light guide 13 to a direction closer to the normal line of the main surface. The detailed configuration of the light source unit 12 will be described later.
　導光体１３は、例えばアクリル樹脂等の光透過性を有する樹脂からなる板体である。導光体１３は、光源部１２が設けられた端面１３ａに近い側から遠い側に向けて厚みが徐々に薄くなる楔形の形状を有している。すなわち、図２に示すように、後述する第１主面１３ｂに垂直な面（ｙｚ平面）で切断したときの導光体１３の断面形状は直角三角形である。導光体１３の端面１３ａは、光源部１２から射出された光を入射させる光入射面である。導光板３の第１主面１３ｂ（図２における上側の面）は、内部に入射した光を射出させる光射出面である。 The light guide 13 is a plate made of a resin having optical transparency such as acrylic resin. The light guide 13 has a wedge shape in which the thickness gradually decreases from the side closer to the end surface 13 a where the light source unit 12 is provided to the side farther from the side. That is, as shown in FIG. 2, the cross-sectional shape of the light guide 13 when cut along a plane (yz plane) perpendicular to the first main surface 13b described later is a right triangle. The end surface 13 a of the light guide 13 is a light incident surface on which light emitted from the light source unit 12 is incident. The first main surface 13b (upper surface in FIG. 2) of the light guide plate 3 is a light emitting surface for emitting light incident on the inside.
　なお、本実施形態において、導光体１３の第１主面１３ｂの面内における光の伝播方向をｙ軸方向、光の伝播方向と直交する方向をｘ軸方向、第１主面と直交する方向（導光体１３の厚み方向）をｚ軸方向、と定義する。すなわち、本明細書における「光の伝播方向」とは、図２に示す導光体１３のｙｚ断面内で光（１点鎖線の矢印Ｌで示す）が反射しつつ伝播する方向を意味するのではなく、導光体１３の第１主面１３ｂの法線方向から見て光が伝播する方向（実線の矢印Ｙで示す）を意味する。 In the present embodiment, the light propagation direction in the first main surface 13b of the light guide 13 is the y-axis direction, the direction orthogonal to the light propagation direction is the x-axis direction, and the first main surface is orthogonal. The direction (thickness direction of the light guide 13) is defined as the z-axis direction. That is, the “light propagation direction” in this specification means a direction in which light (indicated by a dashed line arrow L) propagates while reflecting in the yz section of the light guide 13 shown in FIG. Instead, it means the direction (indicated by solid arrow Y) in which light propagates when viewed from the normal direction of the first main surface 13b of the light guide 13.
　導光体１３の第１主面１３ｂに対向する第２主面１３ｃ（図２における下側の面）は、光の伝播方向において第１主面１３ｂに対して一定の傾斜角をもって傾斜した傾斜面である。第１主面１３ｂに対する第２主面１３ｃの傾斜角θ１（第１主面１３ｂと第２主面１３ｃとのなす角度、導光体１３の先端角と呼ぶ場合もある）は、例えば２°程度に設定される。第２主面１３ｃには、例えばアルミニウム等の光反射率の高い金属膜からなる反射ミラー１５が設けられている。反射ミラー１５が設けられたことで、第２主面１３ｃは、導光体１３の内部を伝播する光を反射させる反射面として機能する。なお、反射ミラー１５は、導光体１３の第２主面１３ｃに直接形成された金属膜であっても良いし、導光体１３とは別体に作製した反射板を貼り合わせた構成であっても良い。 The second main surface 13c (the lower surface in FIG. 2) facing the first main surface 13b of the light guide 13 is inclined with a certain inclination angle with respect to the first main surface 13b in the light propagation direction. Surface. The inclination angle θ1 of the second main surface 13c with respect to the first main surface 13b (the angle between the first main surface 13b and the second main surface 13c, sometimes referred to as the tip angle of the light guide 13) is, for example, 2 °. Set to degree. The second main surface 13c is provided with a reflection mirror 15 made of a metal film having a high light reflectance such as aluminum. By providing the reflection mirror 15, the second main surface 13 c functions as a reflection surface that reflects light propagating through the light guide 13. The reflection mirror 15 may be a metal film directly formed on the second main surface 13 c of the light guide 13, or a configuration in which a reflection plate manufactured separately from the light guide 13 is bonded. There may be.
　光源部１２は、図１に示すように、複数の光源１６が、光の伝播方向Ｙと直交する方向（ｘ軸方向）に１列に配列された構成を有している。光源１６は、図３に示すように、高指向性用光源部（第１光源部）１１３と、広角用光源部（第２光源部）１１４と、から構成されている。高指向性用光源部１１３は、射出光の角度分布が相対的に狭く、高い指向性を有する光を射出する。広角用光源部１１４は、射出光の角度分布が相対的に広く、低い指向性を有する光を射出する。 As shown in FIG. 1, the light source unit 12 has a configuration in which a plurality of light sources 16 are arranged in a line in a direction (x-axis direction) orthogonal to the light propagation direction Y. As illustrated in FIG. 3, the light source 16 includes a light source unit for high directivity (first light source unit) 113 and a light source unit for wide angle (second light source unit) 114. The light source unit 113 for high directivity emits light having a high directivity because the angular distribution of the emitted light is relatively narrow. The wide-angle light source unit 114 emits light having a relatively wide angular distribution and low directivity.
　高指向性用光源部１１３は、図３、図４Ａ、図４Ｂに示すように、第１のＬＥＤ１７（第１の発光素子）と、シリンドリカルレンズ１８（凸レンズ）と、凹面ミラー１９と、を備えている。シリンドリカルレンズ１８は、例えばアクリル樹脂、フェニール系もしくはジメチル系のシリコン樹脂等で構成されている。シリンドリカルレンズ１８は、一方が凸面、他方が平坦面となったレンズ、いわゆる平凸レンズである。光は平坦面１８ａから射出されるため、以降、この平坦面１８ａを光射出面と称する。一方、凸面は、なだらかに湾曲した湾曲面となっている。 As shown in FIGS. 3, 4A, and 4B, the high directivity light source unit 113 includes a first LED 17 (first light emitting element), a cylindrical lens 18 (convex lens), and a concave mirror 19. ing. The cylindrical lens 18 is made of, for example, acrylic resin, phenyl-based or dimethyl-based silicon resin, or the like. The cylindrical lens 18 is a so-called plano-convex lens in which one is a convex surface and the other is a flat surface. Since light is emitted from the flat surface 18a, the flat surface 18a is hereinafter referred to as a light emission surface. On the other hand, the convex surface is a curved surface that is gently curved.
　シリンドリカルレンズ１８をｘｙ平面で切断した断面形状を見ると、図４Ａに示すように、凸面は焦点Ｐ１を有する曲線形状を有している。本実施形態の場合、具体的には、凸面１８ｂの断面形状はパラボラ形状である。一方、シリンドリカルレンズ１８をｙｚ平面で切断した断面形状を見ると、図４Ｂに示すように、湾曲面８ｂは直線形状である。すなわち、シリンドリカルレンズ１８の凸面１８ｂは、ｘｙ平面内において曲率を持ち、ｙｚ平面内においては曲率を持たないパラボラ面である。 Referring to the cross-sectional shape of the cylindrical lens 18 cut along the xy plane, the convex surface has a curved shape having a focal point P1, as shown in FIG. 4A. In the case of this embodiment, specifically, the cross-sectional shape of the convex surface 18b is a parabolic shape. On the other hand, when the cross-sectional shape obtained by cutting the cylindrical lens 18 along the yz plane is viewed, the curved surface 8b is linear as shown in FIG. 4B. That is, the convex surface 18b of the cylindrical lens 18 is a parabolic surface that has a curvature in the xy plane and has no curvature in the yz plane.
　シリンドリカルレンズ１８の凸面１８ｂに沿って凹面ミラー１９が設けられている。凹面ミラー１９は、シリンドリカルレンズ１８の凸面１８ｂに直接形成されたアルミニウム等の光反射率の高い金属膜で構成されている。もしくは、凹面ミラー１９は、ＥＳＲ等の誘電体多層膜で構成されていてもよい。シリンドリカルレンズ１８の凸面１８ｂと凹面ミラー１９とが密着しているため、凹面ミラー１９の形状は凸面１８ｂの形状が反映されたパラボラ面となる。したがって、凹面ミラー１９の焦点の位置はシリンドリカルレンズ１８の焦点の位置と一致する。焦点を図４Ａに点Ｐ１で示す。なお、シリンドリカルレンズ１８の凸面１８ｂに凹面ミラー１９を直接形成する構成に代えて、シリンドリカルレンズ１８とは別体に作製した凹面ミラー（角度分布変換部材ともいう）を貼り合わせた構成としても良い。 A concave mirror 19 is provided along the convex surface 18 b of the cylindrical lens 18. The concave mirror 19 is made of a metal film having a high light reflectance such as aluminum directly formed on the convex surface 18 b of the cylindrical lens 18. Alternatively, the concave mirror 19 may be composed of a dielectric multilayer film such as ESR. Since the convex surface 18b of the cylindrical lens 18 and the concave mirror 19 are in close contact, the shape of the concave mirror 19 is a parabolic surface reflecting the shape of the convex surface 18b. Therefore, the focal position of the concave mirror 19 coincides with the focal position of the cylindrical lens 18. The focal point is indicated by point P1 in FIG. 4A. Instead of the configuration in which the concave mirror 19 is directly formed on the convex surface 18b of the cylindrical lens 18, a configuration may be adopted in which a concave mirror (also referred to as an angle distribution conversion member) manufactured separately from the cylindrical lens 18 is bonded.
　図４Ａに示すように、シリンドリカルレンズ１８の光射出面１８ａには、第１のＬＥＤ１７を内部に挿入できるだけの深さを有する溝１１０が設けられている。シリンドリカルレンズ１８をｘｙ平面で切断したときの溝１１０の底部の断面形状は円弧状に丸められている。溝１１０の内部には、第１のＬＥＤ１７が配置されている。第１のＬＥＤ（第１の発光素子ともいう）１７は、発光面１７ａが凹面ミラー１９に向くように配置されている。また、第１のＬＥＤ１７と凹面ミラー１９およびシリンドリカルレンズ１８とは、凹面ミラー１９およびシリンドリカルレンズ１８の焦点Ｐ１１が発光面１７ａ上に位置するように、互いの位置関係や寸法、形状等が設定されている。 As shown in FIG. 4A, the light exit surface 18a of the cylindrical lens 18 is provided with a groove 110 having a depth that allows the first LED 17 to be inserted therein. The cross-sectional shape of the bottom of the groove 110 when the cylindrical lens 18 is cut along the xy plane is rounded into an arc. Inside the groove 110, the first LED 17 is disposed. The first LED (also referred to as a first light emitting element) 17 is disposed so that the light emitting surface 17 a faces the concave mirror 19. The first LED 17, the concave mirror 19 and the cylindrical lens 18 are set such that their positional relationship, dimensions, and shape are set so that the focal point P11 of the concave mirror 19 and the cylindrical lens 18 is located on the light emitting surface 17a. ing.
　第１のＬＥＤ１７の発光面１７ａが凹面ミラー１９を向いていることにより、第１のＬＥＤ１７の発光面１７ａから射出された光の略全てが凹面ミラー１９に向かい、凹面ミラー１９で反射した後、シリンドリカルレンズ１８の光射出面１８ａから射出される。したがって、第１のＬＥＤ１７の発光面１７ａから射出された光のうち、凹面ミラー１９で反射することなく、直接射出される光はほとんど存在しない。第１のＬＥＤ１７は、特に指向性を有するものではなく、所定の拡散角で光を射出する一般的なＬＥＤを用いることができる。 Since the light emitting surface 17a of the first LED 17 faces the concave mirror 19, almost all of the light emitted from the light emitting surface 17a of the first LED 17 is directed to the concave mirror 19 and reflected by the concave mirror 19, The light exits from the light exit surface 18 a of the cylindrical lens 18. Therefore, among the light emitted from the light emitting surface 17 a of the first LED 17, there is almost no light emitted directly without being reflected by the concave mirror 19. The first LED 17 is not particularly directional, and a general LED that emits light at a predetermined diffusion angle can be used.
　本実施形態においては、図４Ｂに示すように、各シリンドリカルレンズ１８の上面から下面までを貫通するように溝１１０が設けられている。第１のＬＥＤ１７は、シリンドリカルレンズ１８の上端から下端まで達するように、溝１１０の全体にわたって設けられている。
　第１のＬＥＤ１７に電流を供給するための正極側、負極側の２本の配線（図示略）は、シリンドリカルレンズ１８の上端もしくは下端から引き出されている。２本の配線は、シリンドリカルレンズ１８の上端もしくは下端のいずれか一方に揃えて引き出されていることが望ましい。第１のＬＥＤ１７と溝１１０との間には僅かな間隙１１２が設けられている。この間隙１１２には、光学接着剤等が充填されても良いし、何も充填されずに空気が存在していても良い。なお、本実施形態では、複数の別体のシリンドリカルレンズ１８を連結した構成としたが、これら複数のシリンドリカルレンズを一体にした構成のレンチキュラーレンズを用いても良い。 In the present embodiment, as shown in FIG. 4B, a groove 110 is provided so as to penetrate from the upper surface to the lower surface of each cylindrical lens 18. The first LED 17 is provided over the entire groove 110 so as to reach from the upper end to the lower end of the cylindrical lens 18.
Two wires (not shown) on the positive electrode side and the negative electrode side for supplying a current to the first LED 17 are drawn from the upper end or the lower end of the cylindrical lens 18. It is desirable that the two wires are led out to be aligned with either the upper end or the lower end of the cylindrical lens 18. A slight gap 112 is provided between the first LED 17 and the groove 110. The gap 112 may be filled with an optical adhesive or the like, or air may be present without filling anything. In the present embodiment, a plurality of separate cylindrical lenses 18 are connected, but a lenticular lens having a structure in which these plurality of cylindrical lenses are integrated may be used.
　広角用光源部１１４は、図３、図４Ａ、及び図４Ｂに示すように、第２のＬＥＤ（第２の発光素子ともいう）１１５を備えている。第２のＬＥＤ１１５は、発光面１１５ａが導光体１３の端面１３ａに向けて配置されている。したがって、第１のＬＥＤ１７と第２のＬＥＤ１１５とは、互いの発光面１７ａ，１１５ａと反対側の面同士が対向して接するように配置されている。言い換えると、第１のＬＥＤ１７と第２のＬＥＤ１１５とは、背中合わせに配置されている。そのため、第２のＬＥＤ１１５からの光は、シリンドリカルレンズ１８や凹面ミラー１９を通ることなく、導光体１３に入射する。 The wide-angle light source unit 114 includes a second LED (also referred to as a second light emitting element) 115 as shown in FIGS. 3, 4A, and 4B. The second LED 115 is arranged such that the light emitting surface 115 a faces the end surface 13 a of the light guide 13. Accordingly, the first LED 17 and the second LED 115 are arranged such that the surfaces opposite to the light emitting surfaces 17a and 115a face each other. In other words, the first LED 17 and the second LED 115 are arranged back to back. Therefore, the light from the second LED 115 enters the light guide 13 without passing through the cylindrical lens 18 or the concave mirror 19.
　第１のＬＥＤ１７と第２のＬＥＤ１１５の高さ（ｚ軸方向の寸法）は、本実施形態のように異なっていてもよいし、同じであってもよい。第２のＬＥＤ１１５に電流を供給するための配線（図示略）は、シリンドリカルレンズ１８と導光体１３との間隙から引き出されている。
　第２のＬＥＤ１１５に電流を供給するための正極側、負極側の２本の配線（図示略）は、シリンドリカルレンズ１８の上端もしくは下端から引き出されている。第１のＬＥＤ１７と同様、２本の配線は、シリンドリカルレンズ１８の上端もしくは下端のいずれか一方に揃えて引き出されていることが望ましい。第１のＬＥＤ１７と第２のＬＥＤ１１５とは、点灯／消灯を各々独立して制御できるようになっている。 The heights (dimensions in the z-axis direction) of the first LED 17 and the second LED 115 may be different as in the present embodiment, or may be the same. A wiring (not shown) for supplying a current to the second LED 115 is drawn out from the gap between the cylindrical lens 18 and the light guide 13.
Two wires (not shown) on the positive electrode side and the negative electrode side for supplying a current to the second LED 115 are drawn from the upper end or the lower end of the cylindrical lens 18. Similar to the first LED 17, it is desirable that the two wires are drawn out to be aligned with either the upper end or the lower end of the cylindrical lens 18. The first LED 17 and the second LED 115 can be controlled to turn on / off independently.
　第２のＬＥＤ１１５の発光面１１５ａが導光体１３の端面１３ａを向いていることにより、第２のＬＥＤ１１５の発光面１１５ａから射出された光の略全てが導光体１３に入射する。本実施形態の場合、第２のＬＥＤ１１５の発光面１１５ａは導光体１３の端面１３ａに当接しているが、第２のＬＥＤ１１５の発光面１１５ａは導光体１３の端面１３ａに必ずしも当接していなくてもよい。第２のＬＥＤ１１５としては、所定の拡散角で光を射出する一般的なＬＥＤを用いることができる。 Since the light emitting surface 115a of the second LED 115 faces the end surface 13a of the light guide 13, almost all of the light emitted from the light emitting surface 115a of the second LED 115 enters the light guide 13. In the present embodiment, the light emitting surface 115a of the second LED 115 is in contact with the end surface 13a of the light guide 13, but the light emitting surface 115a of the second LED 115 is not necessarily in contact with the end surface 13a of the light guide 13. It does not have to be. As the second LED 115, a general LED that emits light at a predetermined diffusion angle can be used.
　図１および図２に示すように、プリズムシート１４は、導光体１３の光射出面１３ｂに対向する位置（図２における導光体１３の上方）に設けられている。プリズムシート１４は、光の伝播方向Ｙと直交する方向に延在する複数のプリズム構造体１１１が一面に設けられたものである。プリズムシート１４は、複数のプリズム構造体１１１が設けられた面が導光体１３の光射出面１３ｂに対向するように配置されている。ｙｚ平面で切断した断面における一つのプリズム構造体１１１の断面形状は直角三角形状である。プリズム構造体１１１は、導光体１３の光射出面１３ｂに対して直交する第１面１１１ａと、第１面１１１ａに対して所定の先端角θ２をなす第２面１１１ｂと、を有している。 As shown in FIGS. 1 and 2, the prism sheet 14 is provided at a position facing the light exit surface 13b of the light guide 13 (above the light guide 13 in FIG. 2). The prism sheet 14 is provided with a plurality of prism structures 111 extending in a direction orthogonal to the light propagation direction Y on one surface. The prism sheet 14 is disposed so that the surface on which the plurality of prism structures 111 are provided faces the light exit surface 13 b of the light guide 13. The cross-sectional shape of one prism structure 111 in the cross section cut along the yz plane is a right triangle. The prism structure 111 includes a first surface 111a that is orthogonal to the light exit surface 13b of the light guide 13, and a second surface 111b that forms a predetermined tip angle θ2 with respect to the first surface 111a. Yes.
　以下、上記構成の面光源装置１１の作用について説明する。
　第１のＬＥＤ１７の発光面１７ａは所定の面積を有しているため、発光面１７ａ上の全ての点が凹面ミラー１９およびシリンドリカルレンズ１８の焦点Ｐ１１の位置に必ずしも一致するわけではない。ただし、以下では説明を簡単にするため、発光面１７ａの面積が十分に小さく、発光面１７ａが焦点Ｐ１１と一致しているものとして説明する。 Hereinafter, the operation of the surface light source device 11 configured as described above will be described.
Since the light emitting surface 17a of the first LED 17 has a predetermined area, not all points on the light emitting surface 17a necessarily coincide with the positions of the concave mirror 19 and the focal point P11 of the cylindrical lens 18. However, for the sake of simplicity, the following description will be made assuming that the area of the light emitting surface 17a is sufficiently small and the light emitting surface 17a coincides with the focal point P11.
　第１のＬＥＤ１７の発光面１７ａから発せられた光Ｌ１１は、所定の拡散角をもって凹面ミラー１９に向かい、凹面ミラー１９で反射する。ここで、導光体１３の光射出面１３ｂに平行な平面（ｘｙ平面）内での光の振る舞いを考える。図４Ａに示すように、発光面１７ａの位置が焦点Ｐ１１と一致しているため、第１のＬＥＤ１７から発せられた光Ｌは、凹面ミラー１９に対してどのような角度で入射したとしても、凹面ミラー１９で反射した後は凹面ミラー１９の光軸に平行な方向に進行する。したがって、第１のＬＥＤ１７の発光面１７ａから発せられた直後の拡散光は、凹面ミラー１９で反射して平行化された光、すなわち高い指向性を持つ光に変換される。この光Ｌ１１がシリンドリカルレンズ１８の光射出面１８ａから射出し、導光体１３に入射する。 The light L11 emitted from the light emitting surface 17a of the first LED 17 is directed to the concave mirror 19 with a predetermined diffusion angle and reflected by the concave mirror 19. Here, the behavior of light in a plane (xy plane) parallel to the light exit surface 13b of the light guide 13 is considered. As shown in FIG. 4A, since the position of the light emitting surface 17a coincides with the focal point P11, the light L emitted from the first LED 17 can be incident on the concave mirror 19 at any angle. After being reflected by the concave mirror 19, it proceeds in a direction parallel to the optical axis of the concave mirror 19. Therefore, the diffused light immediately after being emitted from the light emitting surface 17a of the first LED 17 is converted into light reflected and collimated by the concave mirror 19, that is, light having high directivity. The light L11 exits from the light exit surface 18a of the cylindrical lens 18 and enters the light guide 13.
　一方、第２のＬＥＤ１１５の発光面１１５ａから発せられた光Ｌ１２は、所定の拡散角をもって導光体１３に入射する。したがって、広角用光源部１１４から射出された光Ｌ１２の角度分布は、高指向性用光源部１１３から射出された光Ｌ１１の角度分布よりも広くなる。 Meanwhile, the light L12 emitted from the light emitting surface 115a of the second LED 115 enters the light guide 13 with a predetermined diffusion angle. Therefore, the angular distribution of the light L12 emitted from the wide-angle light source unit 114 is wider than the angular distribution of the light L11 emitted from the high-directivity light source unit 113.
　次に、光の伝播方向Ｙに平行、かつ導光体１３の光射出面１３ｂに垂直な平面（ｙｚ平面）内での光の振る舞いを考える。図４Ｂに示すように、ｙｚ平面内で見る限り、凹面ミラー１９は曲率を有していないので、凹面ミラー１９は平面ミラーのように機能する。すなわち、第１のＬＥＤ１７から射出された光Ｌ１１は、凹面ミラー１９において入射角に等しい反射角で反射する。よって、光Ｌ１１は、第１のＬＥＤ１７の発光面１７ａから発せられた直後の拡散角を維持したまま、シリンドリカルレンズ１８から射出され、導光体１３に入射する。 Next, consider the behavior of light in a plane (yz plane) parallel to the light propagation direction Y and perpendicular to the light exit surface 13 b of the light guide 13. As shown in FIG. 4B, as long as viewed in the yz plane, the concave mirror 19 has no curvature, so that the concave mirror 19 functions like a plane mirror. That is, the light L11 emitted from the first LED 17 is reflected by the concave mirror 19 at a reflection angle equal to the incident angle. Therefore, the light L <b> 11 is emitted from the cylindrical lens 18 and is incident on the light guide 13 while maintaining the diffusion angle immediately after being emitted from the light emitting surface 17 a of the first LED 17.
　第２のＬＥＤ１１５から射出された光Ｌ１２は、発光面１１５ａから発せられた直後の拡散角を維持したまま、導光体１３の内部を伝播する。 The light L12 emitted from the second LED 115 propagates through the light guide 13 while maintaining the diffusion angle immediately after being emitted from the light emitting surface 115a.
　以上をまとめると、高指向性用光源部１１３については、シリンドリカルレンズ１８の光射出面１８ａから射出された時点において、光Ｌ１１は、導光体１３の光射出面１３ｂに平行な平面（ｘｙ平面）内でのみ高い指向性を持ち、光の伝播方向Ｙに平行、かつ導光体１３の光射出面１３ｂに垂直な平面（ｙｚ平面）内では指向性を持たない。このような光Ｌ１１が、光入射面（端面）１３ａから導光体１３に入射され、導光体１３の内部を伝播する。 In summary, with respect to the high directivity light source unit 113, the light L11 is a plane (xy plane) parallel to the light exit surface 13b of the light guide 13 when it is emitted from the light exit surface 18a of the cylindrical lens 18. ), And has no directivity in a plane (yz plane) parallel to the light propagation direction Y and perpendicular to the light exit surface 13 b of the light guide 13. Such light L11 enters the light guide 13 from the light incident surface (end surface) 13a and propagates inside the light guide 13.
　一方、広角用光源部１１４については、光Ｌ１２は、導光体１３の光射出面１３ｂに平行な平面（ｘｙ平面）内、および光の伝播方向Ｙに平行、かつ導光体１３の光射出面１３ｂに垂直な平面（ｙｚ平面）内の双方で指向性を持たない。このような光Ｌ１２が、導光体１３の内部を伝播する。 On the other hand, with respect to the wide-angle light source unit 114, the light L12 is emitted in a plane (xy plane) parallel to the light emission surface 13b of the light guide 13 and parallel to the light propagation direction Y and emitted from the light guide 13. There is no directivity in both planes (yz plane) perpendicular to the surface 13b. Such light L <b> 12 propagates through the light guide 13.
　次に、導光体１３の内部を伝播する光Ｌ１は、図２に示すように、第１主面１３ｂ（光射出面）と第２主面１３ｃ（反射面）との間で反射を繰り返しつつ、導光体１３の内部を光の伝播方向Ｙ（図２の右側）に向けて進行する。仮に第１主面と第２主面とが平行であったとすると、光が反射を繰り返しても、第１主面および第２主面への光の入射角は変化しない。ところが、本実施形態の場合、導光体１３は光入射面１３ａ側から離れるにつれて厚みが徐々に薄くなる楔形であり、第１主面１３ｂに対して第２主面１３ｃが所定の傾斜角を有している。
　そのため、光Ｌ１は、第１主面１３ｂおよび第２主面１３ｃで反射する毎に第１主面１３ｂおよび第２主面１３ｃへの入射角が小さくなる。 Next, the light L1 propagating through the light guide 13 is repeatedly reflected between the first main surface 13b (light emission surface) and the second main surface 13c (reflection surface) as shown in FIG. Meanwhile, the light guide 13 travels in the light propagation direction Y (right side in FIG. 2). Assuming that the first main surface and the second main surface are parallel, the incident angle of the light to the first main surface and the second main surface does not change even if light is repeatedly reflected. However, in the case of the present embodiment, the light guide 13 has a wedge shape in which the thickness gradually decreases with increasing distance from the light incident surface 13a side, and the second main surface 13c has a predetermined inclination angle with respect to the first main surface 13b. Have.
Therefore, each time the light L1 is reflected by the first main surface 13b and the second main surface 13c, the incident angle on the first main surface 13b and the second main surface 13c becomes small.
　ここで、例えば導光体１３を構成するアクリル樹脂の屈折率が１．５、空気の屈折率を１．０とすると、導光体１３の第１主面１３ｂ（光射出面）における臨界角、すなわち導光体１３を構成するアクリル樹脂と空気との界面における臨界角は、Ｓｎｅｌｌの法則から４２°程度となる。導光体１３に入射した直後の光が第１主面１３ｂに入射した際、第１主面１３ｂへの光Ｌ１の入射角が臨界角である４２°よりも大きい間は全反射条件を満たすため、光Ｌ１は第１主面１３ｂで全反射する。その後、光Ｌ１が第１主面１３ｂと第２主面１３ｃとの間で反射を繰り返し、第１主面１３ｂへの光Ｌ１の入射角が臨界角である４２°よりも小さくなった時点で全反射条件を満たさなくなり、光Ｌ１は外部空間に射出される。 Here, for example, when the refractive index of the acrylic resin constituting the light guide 13 is 1.5 and the refractive index of air is 1.0, the critical angle on the first main surface 13b (light emission surface) of the light guide 13 is shown. That is, the critical angle at the interface between the acrylic resin constituting the light guide 13 and the air is about 42 ° from Snell's law. When the light immediately after entering the light guide 13 enters the first main surface 13b, the total reflection condition is satisfied as long as the incident angle of the light L1 on the first main surface 13b is larger than 42 ° which is a critical angle. Therefore, the light L1 is totally reflected by the first main surface 13b. Thereafter, when the light L1 is repeatedly reflected between the first main surface 13b and the second main surface 13c, the incident angle of the light L1 to the first main surface 13b becomes smaller than 42 ° which is a critical angle. The total reflection condition is not satisfied, and the light L1 is emitted to the external space.
　すなわち、光Ｌ１は、第１主面１３ｂへの入射角が臨界角よりも大きい間は導光体１３の内部に閉じ込められ、第１主面１３ｂへの入射角が臨界角よりも小さくなった時点で第１主面１３ｂから順次射出される。光Ｌ１は第１主面１３ｂから射出される際に屈折するので、第１主面１３ｂへの入射角が４２°程度の光は、射出角が７０°程度の光となって射出される。このように、光の伝播方向Ｙに平行、かつ導光体１３の光射出面１３ｂに垂直な平面（ｙｚ平面）内で見たとき、光Ｌ１は導光体１３に入射した時点では指向性を持たないが、導光体１３から射出する時点では高い指向性を有する。 That is, the light L1 is confined inside the light guide 13 while the incident angle on the first main surface 13b is larger than the critical angle, and the incident angle on the first main surface 13b becomes smaller than the critical angle. At the time, the first main surface 13b is sequentially ejected. Since the light L1 is refracted when emitted from the first main surface 13b, the light having an incident angle of about 42 ° to the first main surface 13b is emitted as light having an emission angle of about 70 °. Thus, when viewed in a plane (yz plane) parallel to the light propagation direction Y and perpendicular to the light exit surface 13b of the light guide 13, the light L1 is directional at the point of incidence on the light guide 13. However, it has high directivity at the time of emission from the light guide 13.
　導光体１３から射出するときの光Ｌ１の射出角は７０°程度であり、光Ｌ１はかなり水平に近い方向に射出される。したがって、プリズムシート１４を用いて、導光体１３から射出された光Ｌ１を導光体１３の第１主面１３ｂの法線方向に近い方向に立ち上げる。具体的には、先端角θ２が３８．５°程度のプリズム構造体１１１を有するプリズムシート１４を用い、光Ｌ１を、プリズム構造体１１１の第１面１１１ａから入射させ、第２面１１１ｂで反射させることで、導光体１３の第１主面１３ｂに対して略法線方向に立ち上げることができる。 The emission angle of the light L1 when emitted from the light guide 13 is about 70 °, and the light L1 is emitted in a substantially horizontal direction. Therefore, using the prism sheet 14, the light L <b> 1 emitted from the light guide 13 is raised in a direction close to the normal direction of the first main surface 13 b of the light guide 13. Specifically, a prism sheet 14 having a prism structure 111 with a tip angle θ2 of about 38.5 ° is used, and light L1 is incident from the first surface 111a of the prism structure 111 and reflected by the second surface 111b. By doing so, the light guide 13 can be raised in a substantially normal direction with respect to the first main surface 13b.
　本実施形態の面光源装置１１を、広い角度分布を有する拡散光を射出するモード、いわゆる広角モードで用いる場合、図５Ａに示すように、第２のＬＥＤ１１５を点灯させ、広角用光源部１１４から光を射出させればよい。この場合、ｘｙ平面において広い角度分布を有する拡散光Ｌ１２が射出される。そして、拡散光Ｌ１２の光路が導光体１３とプリズムシート１４の作用によりｚ軸方向に立ち上げられたとき、ｘｚ平面において広い角度分布を有する拡散光Ｌ１２が射出される。 When the surface light source device 11 of the present embodiment is used in a mode in which diffused light having a wide angular distribution is emitted, so-called wide angle mode, the second LED 115 is turned on as shown in FIG. Light may be emitted. In this case, diffused light L12 having a wide angular distribution in the xy plane is emitted. When the optical path of the diffused light L12 is raised in the z-axis direction by the action of the light guide 13 and the prism sheet 14, the diffused light L12 having a wide angular distribution in the xz plane is emitted.
　これに対して、本実施形態の面光源装置１１を、狭い角度分布を有する平行光に近い光を射出するモード、いわゆる高指向性モードで用いる場合、図５Ｃに示すように、第１のＬＥＤ１７を点灯させ、高指向性用光源部１１３から光を射出させればよい。この場合、ｘｙ平面において狭い角度分布を有する平行光に近い光Ｌ１１が射出される。そして、光Ｌ１１の光路が導光体１３とプリズムシート１４の作用によりｚ軸方向に立ち上げられたとき、ｘｚ平面において狭い角度分布を有する拡散光Ｌ１１が射出される。 On the other hand, when the surface light source device 11 of the present embodiment is used in a mode in which light close to parallel light having a narrow angular distribution is emitted, that is, a so-called high directivity mode, as shown in FIG. Is turned on and light is emitted from the light source unit 113 for high directivity. In this case, light L11 close to parallel light having a narrow angular distribution in the xy plane is emitted. When the optical path of the light L11 is raised in the z-axis direction by the action of the light guide 13 and the prism sheet 14, the diffused light L11 having a narrow angular distribution in the xz plane is emitted.
　また、第１のＬＥＤ１７と第２のＬＥＤ１１５とは点灯、消灯が独立に制御できるため、第１のＬＥＤ１７と第２のＬＥＤ１１５とを同時に点灯させることも可能である。その場合、図５Ｂに示すように、広い角度分布を有する拡散光Ｌ１２と狭い角度分布を有する平行光に近い光Ｌ１１とが混在して導光体１３から射出される。このとき、導光体１３の第１主面１３ｂの法線方向に多くの光が射出されつつ、全体として見れば、広い角度分布を有する射出光が得られる。したがって、第１のＬＥＤ１７と第２のＬＥＤ１１５とを同時に点灯させた場合には広角モードとなる。 Further, since the first LED 17 and the second LED 115 can be controlled to be turned on and off independently, the first LED 17 and the second LED 115 can be turned on simultaneously. In this case, as shown in FIG. 5B, the diffused light L12 having a wide angular distribution and the light L11 close to parallel light having a narrow angular distribution are mixed and emitted from the light guide 13. At this time, a large amount of light is emitted in the normal direction of the first main surface 13b of the light guide 13, and as a whole, emitted light having a wide angular distribution is obtained. Therefore, when the first LED 17 and the second LED 115 are turned on simultaneously, the wide-angle mode is set.
　広角モード、高指向性モードのいずれの場合であっても、図示しないｙｚ平面内の角度分布については、楔状の導光体１３を用いた効果により、ある程度狭い角度分布を有する光が射出される。 Regardless of the wide angle mode or the high directivity mode, the angle distribution in the yz plane (not shown) emits light having a somewhat narrow angle distribution due to the effect of using the wedge-shaped light guide 13. .
　本発明者らは、本実施形態の面光源装置から射出される光の角度分布についてシミュレーションを行った。
　シミュレーションには、照明設計解析ソフトウェア：Light Tools(ver7.2)を用いた。
　シミュレーションの条件は、導光体１３の平面寸法を１３０ｍｍ（ｘ軸方向）×１３０ｍｍ（ｙ軸方向）、シリンドリカルレンズ１８の幅（ｘ軸方向）を２６ｍｍ、シリンドリカルレンズ１８の光軸上の奥行き（ｙ軸方向）を７．５ｍｍ、シリンドリカルレンズ１８の高さ（ｚ軸方向）を４ｍｍ、第１のＬＥＤ１７と第２のＬＥＤ１１５との光射出面の幅（ｘ軸方向）を１ｍｍ、第１のＬＥＤ１７と第２のＬＥＤ１１５との光射出面の高さ（ｚ軸方向）を４ｍｍ、とした。光線の本数を１０００００本、ディテクターのメッシュを１°間隔に設定した。 The present inventors performed a simulation on the angular distribution of light emitted from the surface light source device of this embodiment.
For the simulation, lighting design analysis software: Light Tools (ver. 7.2) was used.
The simulation conditions are as follows: the planar dimension of the light guide 13 is 130 mm (x-axis direction) × 130 mm (y-axis direction), the width of the cylindrical lens 18 (x-axis direction) is 26 mm, and the depth on the optical axis of the cylindrical lens 18 ( y-axis direction) is 7.5 mm, the height of the cylindrical lens 18 (z-axis direction) is 4 mm, the width of the light emission surface of the first LED 17 and the second LED 115 (x-axis direction) is 1 mm, the first The height (z-axis direction) of the light emission surface of the LED 17 and the second LED 115 was 4 mm. The number of rays was set to 100,000, and the detector mesh was set at 1 ° intervals.
　図６は、ｘ軸方向における角度分布を広角モードと高指向性モードとで比較した図である。図６の横軸は、導光体１３の第１主面１３ｂの法線方向を基準（０°）とした極角（°）を示す。図６の縦軸は、最大輝度値を１として規格化した輝度を示す。図６の実線は、広角モードでの角度分布を示す。図６の破線は、高指向性モードでの角度分布を示す。 FIG. 6 is a diagram comparing the angle distribution in the x-axis direction between the wide angle mode and the high directivity mode. The horizontal axis in FIG. 6 represents the polar angle (°) with the normal direction of the first main surface 13b of the light guide 13 as a reference (0 °). The vertical axis in FIG. 6 indicates the luminance normalized with the maximum luminance value being 1. The solid line in FIG. 6 shows the angle distribution in the wide angle mode. The broken line in FIG. 6 shows the angular distribution in the high directivity mode.
　図６に示すように、本実施形態の面光源装置１１は、広角モードにおいて、－６０°から＋６０°程度の範囲の極角にわたって０．２以上の輝度となる広い角度分布を示す。これに対して、本実施形態の面光源装置１１は、高指向性モードにおいては、－３°から＋３°程度の範囲の極角にわたる狭い角度分布を示す。このようにして、本実施形態の面光源装置１１は、広角モードと高指向性モードとで射出光の指向性を切り替えることができる。 As shown in FIG. 6, the surface light source device 11 of the present embodiment exhibits a wide angular distribution with a luminance of 0.2 or more over a polar angle in the range of −60 ° to + 60 ° in the wide-angle mode. In contrast, the surface light source device 11 of the present embodiment exhibits a narrow angular distribution over a polar angle in the range of about −3 ° to + 3 ° in the high directivity mode. In this way, the surface light source device 11 of the present embodiment can switch the directivity of the emitted light between the wide angle mode and the high directivity mode.
　図７は、高指向性モードにおける角度分布を、ｘ軸方向とｙ軸方向とで比較した図である。図７の横軸は、導光体１３の第１主面１３ｂの法線方向を基準（０°）とした極角（°）を示す。図７の縦軸は、最大輝度値を１として規格化した輝度を示す。図７の破線は、ｘ軸方向での輝度分布を示す。図７の実線は、ｙ軸方向での輝度分布を示す。 FIG. 7 is a diagram comparing the angular distribution in the high directivity mode in the x-axis direction and the y-axis direction. The horizontal axis in FIG. 7 indicates the polar angle (°) with the normal direction of the first main surface 13b of the light guide 13 as a reference (0 °). The vertical axis in FIG. 7 indicates the luminance normalized with the maximum luminance value being 1. A broken line in FIG. 7 indicates a luminance distribution in the x-axis direction. The solid line in FIG. 7 shows the luminance distribution in the y-axis direction.
　図７に示すように、ｘ軸方向の角度分布は、図６に示す角度分布と同じものである。すなわち、本実施形態の面光源装置１１は、－３°から＋３°程度の範囲の極角にわたる狭い角度分布を示す。これに対して、本実施形態の面光源装置１１は、ｙ軸方向の角度分布については、ｘ軸方向の角度分布に比べると広がるものの、－１０°から＋２０°程度の範囲の極角にわたる狭い角度分布を示す。なお、ｙ軸方向の角度分布が非対称となるのは、射出光の光路をプリズムシート１４で垂直方向に立ち上げたとしても、まだ立ち上げきれず、導光体１３の端面１３ａと反対側（極角が正となる側）に向けて射出する光の割合が多いからと思われる。 As shown in FIG. 7, the angular distribution in the x-axis direction is the same as the angular distribution shown in FIG. That is, the surface light source device 11 of the present embodiment exhibits a narrow angular distribution over polar angles in the range of about −3 ° to + 3 °. In contrast, in the surface light source device 11 of the present embodiment, the angular distribution in the y-axis direction is wider than the angular distribution in the x-axis direction, but is narrow over a polar angle in the range of about −10 ° to + 20 °. An angular distribution is shown. Note that the angular distribution in the y-axis direction is asymmetric because even if the optical path of the emitted light is raised in the vertical direction by the prism sheet 14, it cannot be raised yet and is opposite to the end face 13 a of the light guide 13 ( This is probably because the proportion of light emitted toward the side where the polar angle is positive) is large.
　本実施形態の面光源装置１１においては、２種類の指向性を切り替えるにあたって２組の導光体を用意し、これら２つの導光体を積層する必要がない。したがって、部品点数が多い、製造コストが高騰する、照明装置全体の厚さが厚くなる、などを解決することができる。また、指向性の切り替え前後で光の伝播方向が変わらないため、導光体１３から射出される光の輝度を均一にするための設計が、どちらのＬＥＤ１７，１１５からの光に対しても有効に働く。したがって、指向性の切り替え前後で輝度を均一に保ちやすくなる。 In the surface light source device 11 of the present embodiment, it is not necessary to prepare two sets of light guides and to stack these two light guides when switching between two types of directivities. Therefore, it is possible to solve problems such as a large number of parts, a high manufacturing cost, and a large thickness of the entire lighting device. In addition, since the light propagation direction does not change before and after switching the directivity, the design for making the luminance of the light emitted from the light guide 13 uniform is effective for the light from either LED 17 or 115. To work. Therefore, it becomes easy to keep the luminance uniform before and after switching the directivity.
　本実施形態の場合、第１のＬＥＤ１７と第２のＬＥＤ１１５とが背中合わせに配置されているため、凹面ミラー１９の側から見ると、第２のＬＥＤ１１５は第１のＬＥＤ１７の裏側に隠れた状態となる。そのため、第１のＬＥＤ１７を点灯させた際に、第１のＬＥＤ１７の裏側の領域はもともと影となる領域であるから、第２のＬＥＤ１１５による影がそれ以上に増えることがない。 In the case of this embodiment, since the first LED 17 and the second LED 115 are arranged back to back, the second LED 115 is hidden from the back side of the first LED 17 when viewed from the concave mirror 19 side. Become. For this reason, when the first LED 17 is turned on, the area behind the first LED 17 is originally a shadow area, so that the shadow of the second LED 115 does not increase any more.
［第１変形例］
　上記実施形態では、楔状の導光体を用いたが、この構成に代えて、図８に示す導光体を用いてもよい。
　本変形例の面光源装置１１７の導光体１１８は、図８に示すように、第１主面１１８ｂ（光射出面）と対向する第２主面１１８ｃ側に複数のプリズム構造体１１９を備えている。各プリズム構造体１１９は、光の伝播方向Ｙと直交する方向に延在している。ｙｚ平面で切断した断面におけるプリズム構造体１１９の断面形状は直角三角形状である。プリズム構造体１１９は、導光体１１８の第１主面１１８ｂに対して直交する第１面１１９ａと、第１面１１９ａに対して所定の先端角θ２をなす第２面１１９ｂと、を有している。第２面１１９ｂは、導光体１１８の内部を伝播する光を反射させる反射面として機能する。 [First Modification]
In the above embodiment, a wedge-shaped light guide is used, but instead of this configuration, a light guide shown in FIG. 8 may be used.
As shown in FIG. 8, the light guide 118 of the surface light source device 117 of the present modification includes a plurality of prism structures 119 on the second main surface 118c side facing the first main surface 118b (light emission surface). ing. Each prism structure 119 extends in a direction orthogonal to the light propagation direction Y. The cross-sectional shape of the prism structure 119 in the cross section cut along the yz plane is a right triangle. The prism structure 119 includes a first surface 119a that is orthogonal to the first main surface 118b of the light guide 118, and a second surface 119b that forms a predetermined tip angle θ2 with respect to the first surface 119a. ing. The second surface 119b functions as a reflecting surface that reflects light propagating through the light guide 118.
　すなわち、楔状の導光体が連続した一つの反射面を有するのに対し、本変形例の導光体１１８は分割された複数の反射面を有する。したがって、本変形例の導光体１１８も、楔状の導光体と同様の作用により、射出光に高い指向性を与えることができる。 That is, while the wedge-shaped light guide has one continuous reflection surface, the light guide 118 of the present modification has a plurality of divided reflection surfaces. Therefore, the light guide 118 of this modification can also give high directivity to the emitted light by the same action as the wedge-shaped light guide.
［第２変形例］
　上記実施形態では、楔状の導光体を用いたが、この構成に代えて、図９に示す導光体を用いてもよい。
　本変形例の面光源装置１２１は、図９に示すように、第１主面１２２ｂ（光射出面）と第２主面１２２ｃとが平行な平行平板からなる導光体１２２を備えている。導光体１２２の第２主面１２２ｃには、プリズム状の断面形状を有する複数の溝や印刷物（図示略）が設けられている。複数の溝や印刷物は、光源部１２が設けられた端面１２２ａに近い程密度が低く、端面１２２ａから遠い程密度が高くなるように配置されている。導光体１２２を伝播する光は、複数の溝や印刷物によって反射角度を変更され、導光体１２２から射出される。 [Second Modification]
In the above embodiment, the wedge-shaped light guide is used, but instead of this configuration, the light guide shown in FIG. 9 may be used.
As shown in FIG. 9, the surface light source device 121 of the present modification includes a light guide body 122 formed of parallel flat plates in which a first main surface 122b (light emission surface) and a second main surface 122c are parallel. The second main surface 122c of the light guide 122 is provided with a plurality of grooves and printed matter (not shown) having a prismatic cross-sectional shape. The plurality of grooves and printed matter are arranged so that the density is lower as the distance from the end surface 122a provided with the light source unit 12 is lower, and the density is higher as the distance from the end surface 122a is longer. The light propagating through the light guide 122 is changed in reflection angle by a plurality of grooves and printed matter, and emitted from the light guide 122.
　本変形例の面光源装置１２１の場合も、指向性の切り替え前後で光の伝播方向Ｙが変わらないため、射出光の輝度を均一にするための複数の溝や印刷物の配置がどちらのＬＥＤ１７，１１５からの光に対しても有効に働く。したがって、指向性の切り替え前後で輝度を均一に保ちやすくなる。 Also in the case of the surface light source device 121 of this modification, the light propagation direction Y does not change before and after switching the directivity, and therefore, the arrangement of the plurality of grooves and printed matter for making the brightness of the emitted light uniform is which LED 17, It works effectively against the light from 115. Therefore, it becomes easy to keep the luminance uniform before and after switching the directivity.
［第２実施形態］
　以下、本発明の第２実施形態について、図１０を用いて説明する。
　本実施形態の面光源装置の基本構成は第１実施形態と同様であり、光源部の構成が第１実施形態と異なる。
　図１０は、本実施形態の面光源装置における光源部を示す斜視図である。図１１は、本実施形態の面光源装置を示す平面図である。
　図１０、図１１において第１実施形態で用いた図面と共通の構成要素には同一の符号を付し、説明を省略する。 [Second Embodiment]
Hereinafter, a second embodiment of the present invention will be described with reference to FIG.
The basic configuration of the surface light source device of this embodiment is the same as that of the first embodiment, and the configuration of the light source unit is different from that of the first embodiment.
FIG. 10 is a perspective view showing a light source unit in the surface light source device of this embodiment. FIG. 11 is a plan view showing the surface light source device of this embodiment.
In FIG. 10 and FIG. 11, the same components as those used in the first embodiment are denoted by the same reference numerals, and the description thereof is omitted.
　第１実施形態では、第２のＬＥＤが第１のＬＥＤと背中合わせに配置されていた。これに対して、本実施形態の面光源装置１２４では、図１０、図１１に示すように、第２のＬＥＤ１１５は、隣り合う２つの凹面ミラー１９の境界に沿って配置されている。ただし、第２のＬＥＤ１１５は、隣り合う２つの凹面ミラー１９の全ての境界に配置されておらず、一つおきの境界に配置されている。本実施形態では、第１のＬＥＤ１７と第２のＬＥＤ１１５を同じ大きさとしたが、第１実施形態のように異なっていてもよい。 In the first embodiment, the second LED is arranged back to back with the first LED. On the other hand, in the surface light source device 124 of this embodiment, as shown in FIGS. 10 and 11, the second LED 115 is disposed along the boundary between two adjacent concave mirrors 19. However, the second LEDs 115 are not arranged at every boundary between the two adjacent concave mirrors 19 but are arranged at every other boundary. In the present embodiment, the first LED 17 and the second LED 115 have the same size, but may be different as in the first embodiment.
　第２のＬＥＤ１１５は、第１実施形態と同様、発光面１１５ａが導光体１３の端面１３ａを向くように配置されている。ただし、第２のＬＥＤ１１５の発光面１１５ａがシリンドリカルレンズ１８の光射出面１８ａに対して充分な大きさを占める場合には、第２のＬＥＤ１１５の発光面１１５ａがシリンドリカルレンズ１８を向いていてもよい。その場合、第２のＬＥＤ１１５からの光Ｌ１２は、シリンドリカルレンズ１８に入射し、凹面ミラー１９で反射した後に導光体１３に入射する。ところが、第２のＬＥＤ１１５の設置位置が凹面ミラー１９の焦点から大きくずれているため、第２のＬＥＤ１１５から射出されて凹面ミラー１９で反射した光は平行化されることがない。その結果、第２のＬＥＤ１１５の発光面１１５ａをシリンドリカルレンズ１８側に向けた場合も、第２のＬＥＤ１１５からは拡散光が得られることになる。 2nd LED115 is arrange | positioned so that the light emission surface 115a may face the end surface 13a of the light guide 13 similarly to 1st Embodiment. However, when the light emitting surface 115a of the second LED 115 occupies a sufficient size with respect to the light emitting surface 18a of the cylindrical lens 18, the light emitting surface 115a of the second LED 115 may face the cylindrical lens 18. . In that case, the light L12 from the second LED 115 enters the cylindrical lens 18, is reflected by the concave mirror 19, and then enters the light guide 13. However, since the installation position of the second LED 115 is greatly deviated from the focal point of the concave mirror 19, the light emitted from the second LED 115 and reflected by the concave mirror 19 is not collimated. As a result, diffused light can be obtained from the second LED 115 even when the light emitting surface 115a of the second LED 115 faces the cylindrical lens 18 side.
　本実施形態においても、第１実施形態と同様、第１のＬＥＤ１７を点灯させることにより高指向性モードの照明が実現でき、第２のＬＥＤ１１５を点灯させることにより広角モードの照明が実現できる。また、第１のＬＥＤ１７と第２のＬＥＤ１１５とを同時に点灯させた場合、広角モードの照明が実現できる点も第１実施形態と同様である。 Also in this embodiment, as in the first embodiment, lighting in the high directivity mode can be realized by turning on the first LED 17, and lighting in the wide angle mode can be realized by turning on the second LED 115. Moreover, when the 1st LED17 and the 2nd LED115 are lighted simultaneously, the point which can implement | achieve illumination of a wide angle mode is the same as that of 1st Embodiment.
　本実施形態においても、部品点数や製造コストの増大を招くことなく、指向性の切り替え前後で輝度を均一に保つことができる面光源装置が実現できる、という第１実施形態と同様の効果が得られる。 Also in this embodiment, the same effect as that of the first embodiment can be obtained that a surface light source device that can keep the luminance uniform before and after switching the directivity without increasing the number of parts and the manufacturing cost can be realized. It is done.
　その他、本実施形態特有の効果として、以下の点が挙げられる。
　シリンドリカルレンズ１８から射出される光の輝度分布は、シリンドリカルレンズ１８の中央部から射出される光の輝度が大きく、シリンドリカルレンズ１８の端部から射出される光の輝度が小さくなる傾向を持っている。ここで、本実施形態の面光源装置１２４の場合、第２のＬＥＤ１１５が隣り合う２つの凹面ミラー１９の境界に沿って配置されている。したがって、広角モードにおいて第１のＬＥＤ１７と第２のＬＥＤ１１５とを同時に点灯させたとすると、第１のＬＥＤ１７による光の輝度が小さい領域に第２のＬＥＤ１１５からの光が照射される。その結果、輝度ムラを低減することができる。 In addition, the following points can be cited as effects unique to the present embodiment.
The luminance distribution of light emitted from the cylindrical lens 18 has a tendency that the luminance of light emitted from the central portion of the cylindrical lens 18 is large and the luminance of light emitted from the end portion of the cylindrical lens 18 is small. . Here, in the case of the surface light source device 124 of the present embodiment, the second LED 115 is disposed along the boundary between two adjacent concave mirrors 19. Therefore, if the first LED 17 and the second LED 115 are simultaneously turned on in the wide-angle mode, the light from the second LED 115 is applied to an area where the light intensity of the first LED 17 is low. As a result, luminance unevenness can be reduced.
［第１変形例］
　上記実施形態では、第２のＬＥＤ１１５は、隣り合う２つの凹面ミラー１９の境界のうち、一つおきの境界に配置されていた。この構成に代えて、第２のＬＥＤ１１５を図１２に示す配置としてもよい。
　本変形例の面光源装置２６は、図１２に示すように、第２のＬＥＤ１１５が、隣り合う２つの凹面ミラー１９の境界の全てに配置されている。したがって、一つの面光源装置２６において、第１のＬＥＤ１７の数と第２のＬＥＤ１１５の数は同じでもよいし、異なっていてもよい。 [First Modification]
In the said embodiment, 2nd LED115 was arrange | positioned at every other boundary among the boundaries of the adjacent two concave mirrors 19. FIG. Instead of this configuration, the second LED 115 may be arranged as shown in FIG.
In the surface light source device 26 of this modification, as shown in FIG. 12, the second LEDs 115 are arranged on all the boundaries between two adjacent concave mirrors 19. Therefore, in one surface light source device 26, the number of the first LEDs 17 and the number of the second LEDs 115 may be the same or different.
［第３実施形態］
　以下、本発明の第３実施形態について、図１３、図１４Ａ、及び図１４Ｂを用いて説明する。
　本実施形態の面光源装置の基本構成は第１実施形態と同様であり、光源部の構成が第１実施形態と異なる。
　図１３は、本実施形態の面光源装置における光源部を示す斜視図である。図１４Ａは、本実施形態の面光源装置を示す側面図である。図１４Ｂは、本実施形態の面光源装置を示す平面図である。
　図１３、図１４Ａ、及び図１４Ｂにおいて、第１実施形態で用いた図面と共通の構成要素には同一の符号を付し、説明を省略する。 [Third Embodiment]
Hereinafter, a third embodiment of the present invention will be described with reference to FIGS. 13, 14A, and 14B.
The basic configuration of the surface light source device of this embodiment is the same as that of the first embodiment, and the configuration of the light source unit is different from that of the first embodiment.
FIG. 13 is a perspective view showing a light source unit in the surface light source device of this embodiment. FIG. 14A is a side view showing the surface light source device of the present embodiment. FIG. 14B is a plan view showing the surface light source device of the present embodiment.
In FIG. 13, FIG. 14A, and FIG. 14B, the same code | symbol is attached | subjected to the same component as drawing used in 1st Embodiment, and description is abbreviate | omitted.
　第１実施形態では、第２のＬＥＤが第１のＬＥＤと背中合わせに配置されていた。これに対して、本実施形態の面光源装置１２８では、図１３、図１４Ａ、及び図１４Ｂに示すように、第２のＬＥＤ１１５は、シリンドリカルレンズ１８の上面および下面と平行な方向に沿って配置されている。したがって、第１のＬＥＤ１７と第２のＬＥＤ１１５とは、互いの長手方向が直交するように配置される。 In the first embodiment, the second LED is arranged back to back with the first LED. On the other hand, in the surface light source device 128 of the present embodiment, as shown in FIGS. 13, 14A, and 14B, the second LED 115 is arranged along a direction parallel to the upper surface and the lower surface of the cylindrical lens 18. Has been. Therefore, the first LED 17 and the second LED 115 are arranged so that their longitudinal directions are orthogonal to each other.
　凹面ミラー１９は、図１４Ａに示すように、ｙｚ平面で切断したときの断面形状が直線形状であって、導光体１３の第１主面３ａに垂直な方向には曲率を持っていない。これにより、ｘｙ平面においては、凹面ミラー１９は、ｚ軸方向に沿って連続して存在する焦点を有するが、ｙｚ平面においては、凹面ミラー１９は、ｘ軸方向に沿って連続して存在する焦点を有していない。したがって、第１のＬＥＤ１７がｚ軸方向に沿って配置されている場合、第１のＬＥＤ１７の発光面１７ａは凹面ミラー１９の焦点と一致する。一方、第２のＬＥＤ１１５がｘ軸方向に沿って配置されている場合、第２のＬＥＤ１１５の発光面１１５ａは凹面ミラー１９の焦点からずれた位置となる。 As shown in FIG. 14A, the concave mirror 19 has a straight cross-sectional shape when cut along the yz plane, and has no curvature in a direction perpendicular to the first main surface 3 a of the light guide 13. Thus, in the xy plane, the concave mirror 19 has a focal point that continuously exists along the z-axis direction, but in the yz plane, the concave mirror 19 exists continuously along the x-axis direction. Has no focus. Therefore, when the first LED 17 is arranged along the z-axis direction, the light emitting surface 17 a of the first LED 17 coincides with the focal point of the concave mirror 19. On the other hand, when the second LED 115 is arranged along the x-axis direction, the light emitting surface 115 a of the second LED 115 is shifted from the focal point of the concave mirror 19.
　第２のＬＥＤ１１５は、第１実施形態と同様、発光面１１５ａが導光体１３の端面１３ａを向くように配置されている。ただし、第２のＬＥＤ１１５は、発光面１１５ａがシリンドリカルレンズ１８を向くくように配置されていてもよい。その場合、第２のＬＥＤ１１５からの光は、シリンドリカルレンズ１８に入射し、凹面ミラー１９で反射した後に導光体１３に入射する。ところが、第２のＬＥＤ１１５の発光面１１５ａが凹面ミラー１９の焦点からずれているため、第２のＬＥＤ１１５から射出されて凹面ミラー１９で反射した光は平行化されることがない。その結果、第２のＬＥＤ１１５の発光面１１５ａをシリンドリカルレンズ１８側に向けた場合も、第２のＬＥＤ１１５からは拡散光が得られることになる。 2nd LED115 is arrange | positioned so that the light emission surface 115a may face the end surface 13a of the light guide 13 similarly to 1st Embodiment. However, the second LED 115 may be arranged such that the light emitting surface 115a faces the cylindrical lens 18. In that case, the light from the second LED 115 enters the cylindrical lens 18, is reflected by the concave mirror 19, and then enters the light guide 13. However, since the light emitting surface 115a of the second LED 115 is shifted from the focal point of the concave mirror 19, the light emitted from the second LED 115 and reflected by the concave mirror 19 is not collimated. As a result, diffused light can be obtained from the second LED 115 even when the light emitting surface 115a of the second LED 115 faces the cylindrical lens 18 side.
　本実施形態においても、第１実施形態と同様、第１のＬＥＤ１７を点灯させることにより高指向性モードの照明が実現でき、第２のＬＥＤ１１５を点灯させることにより広角モードの照明が実現できる。また、第１のＬＥＤ１７と第２のＬＥＤ１１５とを同時に点灯させた場合、広角モードの照明が実現できる点も第１実施形態と同様である。 Also in this embodiment, as in the first embodiment, lighting in the high directivity mode can be realized by turning on the first LED 17, and lighting in the wide angle mode can be realized by turning on the second LED 115. Moreover, when the 1st LED17 and the 2nd LED115 are lighted simultaneously, the point which can implement | achieve illumination of a wide angle mode is the same as that of 1st Embodiment.
　本実施形態においても、部品点数や製造コストの増大を招くことなく、指向性の切り替え前後で輝度を均一に保つことができる面光源装置が実現できる、という第１実施形態と同様の効果が得られる。 Also in this embodiment, the same effect as that of the first embodiment can be obtained that a surface light source device that can keep the luminance uniform before and after switching the directivity without increasing the number of parts and the manufacturing cost can be realized. It is done.
［第１変形例］
　上記実施形態では、一つの第２のＬＥＤがｘ軸方向に沿って配置されていた。この構成に代えて、第２のＬＥＤを図１５に示す構成としてもよい。
　本変形例の光源１３０は、図１５に示すように、複数個の第２のＬＥＤ１１５がｘ軸方向に沿って所定の間隔をおいて配置されている。このように、複数個の第２のＬＥＤ１１５を、点光源のように、シリンドリカルレンズ１８の上面および下面と平行な方向に沿って配置してもよい。 [First Modification]
In the said embodiment, one 2nd LED was arrange | positioned along the x-axis direction. Instead of this configuration, the second LED may be configured as shown in FIG.
As shown in FIG. 15, the light source 130 according to the present modification includes a plurality of second LEDs 115 arranged at predetermined intervals along the x-axis direction. Thus, you may arrange | position several 2nd LED115 along the direction parallel to the upper surface and lower surface of the cylindrical lens 18 like a point light source.
［第４実施形態］
　以下、本発明の第４実施形態について、図１６、図１７を用いて説明する。
　本実施形態の面光源装置の基本構成は第１実施形態と同様であり、光源部の構成が第１実施形態と異なる。
　図１６は、本実施形態の面光源装置における光源部を示す斜視図である。図１７は、本実施形態の面光源装置を示す平面図である。
　図１６、図１７において、第１実施形態で用いた図面と共通の構成要素には同一の符号を付し、説明を省略する。 [Fourth Embodiment]
Hereinafter, a fourth embodiment of the present invention will be described with reference to FIGS. 16 and 17.
The basic configuration of the surface light source device of this embodiment is the same as that of the first embodiment, and the configuration of the light source unit is different from that of the first embodiment.
FIG. 16 is a perspective view showing a light source unit in the surface light source device of this embodiment. FIG. 17 is a plan view showing the surface light source device of this embodiment.
In FIG. 16 and FIG. 17, the same code | symbol is attached | subjected to the same component as drawing used in 1st Embodiment, and description is abbreviate | omitted.
　本実施形態の面光源装置３２の光源部３３において、図１６、図１７に示すように、第２のＬＥＤ１１５は、複数のシリンドリカルレンズ１８に跨って、各シリンドリカルレンズ１８の上面および下面と平行な方向に長く延在して配置されている。 In the light source unit 33 of the surface light source device 32 of the present embodiment, as shown in FIGS. 16 and 17, the second LED 115 extends across the plurality of cylindrical lenses 18 and is parallel to the upper and lower surfaces of each cylindrical lens 18. It is arranged to extend long in the direction.
　第２のＬＥＤ１１５は、第１実施形態と同様、発光面１１５ａが導光体１３の端面１３ａを向くように配置されている。ただし、第２のＬＥＤ１１５は、発光面１１５ａがシリンドリカルレンズ１８を向くように配置されていてもよい。上述したように、第２のＬＥＤ１１５の発光面１１５ａをシリンドリカルレンズ１８側に向けた場合も、第２のＬＥＤ１１５からは拡散光が得られる。 2nd LED115 is arrange | positioned so that the light emission surface 115a may face the end surface 13a of the light guide 13 similarly to 1st Embodiment. However, the second LED 115 may be arranged such that the light emitting surface 115a faces the cylindrical lens 18. As described above, even when the light emitting surface 115a of the second LED 115 is directed toward the cylindrical lens 18, the diffused light can be obtained from the second LED 115.
　第１のＬＥＤ１７は、隣り合うシリンドリカルレンズ１８において、シリンドリカルレンズ１８の上部もしくは下部に交互に配置されている。第１のＬＥＤ１７は、凹面ミラー１９の焦点に位置していればよいため、必ずしもシリンドリカルレンズ１８の上面および下面と垂直な方向（ｚ軸方向）に長く延在している必要はなく、このように点光源として設置されていてもよい。 1st LED17 is alternately arrange | positioned in the upper part or the lower part of the cylindrical lens 18 in the cylindrical lens 18 adjacent. Since the first LED 17 only needs to be positioned at the focal point of the concave mirror 19, it does not necessarily have to extend long in the direction (z-axis direction) perpendicular to the upper surface and the lower surface of the cylindrical lens 18. It may be installed as a point light source.
　本実施形態においても、第１実施形態と同様、第１のＬＥＤ１７を点灯させることにより高指向性モードの照明が実現でき、第２のＬＥＤ１１５を点灯させることにより広角モードの照明が実現できる。また、第１のＬＥＤ１７と第２のＬＥＤ１１５とを同時に点灯させた場合、広角モードの照明が実現できる点も第１実施形態と同様である。 Also in this embodiment, as in the first embodiment, lighting in the high directivity mode can be realized by turning on the first LED 17, and lighting in the wide angle mode can be realized by turning on the second LED 115. Moreover, when the 1st LED17 and the 2nd LED115 are lighted simultaneously, the point which can implement | achieve illumination of a wide angle mode is the same as that of 1st Embodiment.
　本実施形態においても、部品点数や製造コストの増大を招くことなく、指向性の切り替え前後で輝度を均一に保つことができる面光源装置が実現できる、という第１実施形態と同様の効果が得られる。 Also in this embodiment, the same effect as that of the first embodiment can be obtained that a surface light source device that can keep the luminance uniform before and after switching the directivity without increasing the number of parts and the manufacturing cost can be realized. It is done.
［第５実施形態］
　以下、本発明の第５実施形態について、図１８～図２１を用いて説明する。
　本実施形態の面光源装置の導光体の構成は第１実施形態と同様であり、光源部の構成が第１実施形態と異なる。
　図１８は、本実施形態の面光源装置における光源部を示す斜視図である。図１９Ａは、光源部の平面図である。図１９Ｂは、光源部の側面図である。図２０は、高指向性用光源部における光の作用を説明するための図である。図２１は、本実施形態の効果を説明するための図である。
　図１８～図２１において、第１実施形態で用いた図面と共通の構成要素には同一の符号を付し、説明を省略する。 [Fifth Embodiment]
Hereinafter, a fifth embodiment of the present invention will be described with reference to FIGS.
The configuration of the light guide of the surface light source device of this embodiment is the same as that of the first embodiment, and the configuration of the light source unit is different from that of the first embodiment.
FIG. 18 is a perspective view showing a light source unit in the surface light source device of this embodiment. FIG. 19A is a plan view of the light source unit. FIG. 19B is a side view of the light source unit. FIG. 20 is a diagram for explaining the action of light in the light source unit for high directivity. FIG. 21 is a diagram for explaining the effect of the present embodiment.
18 to 21, the same reference numerals are given to the same components as those used in the first embodiment, and the description thereof will be omitted.
　本実施形態の面光源装置１３５において、光源部１３６は、図１８、図１９Ｂに示すように、導光体１３の厚さ方向（ｚ軸方向）に積層された高指向性用光源部１３７（第１の光源部）と広角用光源部１３８（第２の光源部）とから構成されている。本実施形態では、上段に高指向性用光源部１３７が配置され、下段に広角用光源部１３８が配置されている。ただし、これとは逆に、上段に広角用光源部１３８が配置され、下段に高指向性用光源部１３７が配置されていてもよい。 In the surface light source device 135 of the present embodiment, the light source unit 136 includes a high directivity light source unit 137 (stacked in the thickness direction (z-axis direction) of the light guide 13 as shown in FIGS. 18 and 19B. The first light source unit) and a wide-angle light source unit 138 (second light source unit). In the present embodiment, the high directivity light source unit 137 is arranged in the upper stage, and the wide angle light source unit 138 is arranged in the lower stage. However, conversely, the wide-angle light source unit 138 may be disposed in the upper stage, and the high directivity light source unit 137 may be disposed in the lower stage.
　高指向性用光源部１３７は、図１８、図１９Ａに示すように、第１のＬＥＤ１７（第１の発光素子）と、楔形導光棒１３９（反射素子または角度分布変換部材ともいう）と、入射角調整用プリズム１４０と、を備えている。第１のＬＥＤ１７は、楔形導光棒１３９の長手方向の端面１３９ａに設けられている。
　第１のＬＥＤ１７は楔形導光棒１３９と当接し、発光面１７ａが楔形導光棒１３９の端面１３９ａを向くように固定されている。入射角調整用プリズム１４０は、楔形導光棒１３９と導光体１３との間に配置されている。第１のＬＥＤ１７には、拡散光を射出する一般のＬＥＤを用いることができる。　 As shown in FIGS. 18 and 19A, the high directivity light source unit 137 includes a first LED 17 (first light emitting element), a wedge-shaped light guide rod 139 (also referred to as a reflective element or an angle distribution conversion member), And an incident angle adjusting prism 140. The first LED 17 is provided on the end surface 139 a in the longitudinal direction of the wedge-shaped light guide bar 139.
The first LED 17 is in contact with the wedge-shaped light guide rod 139, and is fixed so that the light emitting surface 17a faces the end surface 139a of the wedge-shaped light guide rod 139. The incident angle adjusting prism 140 is disposed between the wedge-shaped light guide rod 139 and the light guide 13. As the first LED 17, a general LED that emits diffused light can be used.
　楔形導光棒１３９は、例えばアクリル樹脂等の光透過性を有する樹脂からなる棒体である。楔形導光棒１３９の構成材料は、導光体１３と同様のものを用いることができる。楔形導光棒１３９は、第１のＬＥＤ１７が設けられた端面１３９ａに近い側から遠い側に向けて幅（ｙ軸方向の寸法）が徐々に狭くなる楔形の形状を有している。すなわち、図１９Ａに示すように、導光体１３の第１主面３ａの法線方向から見たときの楔形導光棒１３９の平面形状は直角三角形である。楔形導光棒１３９の端面１３９ａは、第１のＬＥＤ１７から射出された光を入射させる光入射面である。楔形導光棒１３９の第１側面１３９ｂ（図１９Ａにおける端面１３９ａに垂直な面）は、内部に入射した光を射出させる光射出面である。 The wedge-shaped light guide rod 139 is a rod body made of a resin having optical transparency such as acrylic resin. As the constituent material of the wedge-shaped light guide rod 139, the same material as that of the light guide 13 can be used. The wedge-shaped light guide rod 139 has a wedge shape in which the width (dimension in the y-axis direction) gradually decreases from the side closer to the end surface 139a provided with the first LED 17 toward the far side. That is, as shown in FIG. 19A, the planar shape of the wedge-shaped light guide bar 139 when viewed from the normal direction of the first main surface 3a of the light guide 13 is a right triangle. The end surface 139a of the wedge-shaped light guide rod 139 is a light incident surface on which light emitted from the first LED 17 is incident. The first side surface 139b of the wedge-shaped light guide rod 139 (a surface perpendicular to the end surface 139a in FIG. 19A) is a light emitting surface that emits light incident on the inside.
　楔形導光棒１３９の第１側面１３９ｂに対向する第２側面１３９ｃ（図１９Ａにおける斜面）は、光の伝播方向Ｘにおいて第１側面１３９ｂに対して一定の傾斜角をもって傾斜した傾斜面である。第２側面１３９ｃには、例えばアルミニウム等の光反射率の高い金属膜からなる反射ミラーが設けられていてもよい。その場合、反射ミラーは、楔形導光棒１３９の第２側面１３９ｃに直接形成された金属膜であっても良いし、楔形導光棒１３９とは別体に作製した反射板を貼り合わせた構成であっても良い。 The second side surface 139c (the inclined surface in FIG. 19A) facing the first side surface 139b of the wedge-shaped light guide rod 139 is an inclined surface that is inclined with a certain inclination angle with respect to the first side surface 139b in the light propagation direction X. The second side surface 139c may be provided with a reflection mirror made of a metal film having a high light reflectance such as aluminum. In that case, the reflection mirror may be a metal film directly formed on the second side surface 139c of the wedge-shaped light guide rod 139, or a configuration in which a reflector made separately from the wedge-shaped light guide rod 139 is bonded. It may be.
　入射角調整用プリズム１４０は、複数のプリズム構造体１４１が一面に設けられたものである。入射角調整用プリズム１４０は、複数のプリズム構造体１４１が設けられた面が楔形導光棒１３９の光射出面３９ｂに対向するように配置されている。ｘｙ平面で切断した断面におけるプリズム構造体１４１の断面形状は直角三角形状である。プリズム構造体１４１は、楔形導光棒１３９の光射出面３９ｂに対して直交する第１面１４１ａと、第１面１４１ａに対して所定の先端角θ１３をなす第２面１４１ｂと、を有している。 The incident angle adjusting prism 140 includes a plurality of prism structures 141 provided on one surface. The incident angle adjusting prism 140 is disposed such that the surface on which the plurality of prism structures 141 are provided faces the light exit surface 39b of the wedge-shaped light guide rod 139. The cross-sectional shape of the prism structure 141 in the cross section cut along the xy plane is a right triangle. The prism structure 141 has a first surface 141a orthogonal to the light exit surface 39b of the wedge-shaped light guide rod 139, and a second surface 141b that forms a predetermined tip angle θ13 with respect to the first surface 141a. ing.
　広角用光源部１３８は、図１８、図１９Ａに示すように、３個の第２のＬＥＤ１１５を備えている。本実施形態では、第２のＬＥＤ１１５として３個のＬＥＤを用いるが、ＬＥＤの個数は特に限定されない。第２のＬＥＤ１１５は、発光面１１５ａが導光体１３の端面１３ａに向くように配置されている。したがって、第２のＬＥＤ１１５から射出された光は、楔形導光棒１３９や入射角調整用プリズム１４０を通ることなく、導光体１３に入射する。第２のＬＥＤ１１５には、拡散光を射出する一般のＬＥＤを用いることができる。 The wide-angle light source unit 138 includes three second LEDs 115 as shown in FIGS. 18 and 19A. In the present embodiment, three LEDs are used as the second LED 115, but the number of LEDs is not particularly limited. The second LED 115 is disposed so that the light emitting surface 115 a faces the end surface 13 a of the light guide 13. Therefore, the light emitted from the second LED 115 enters the light guide 13 without passing through the wedge-shaped light guide rod 139 and the incident angle adjusting prism 140. As the second LED 115, a general LED that emits diffused light can be used.
　以下、上記構成の面光源装置１３５の作用について説明する。
　最初に、高指向性用光源部１３７について、図２０を用いて説明する。
　第１のＬＥＤ１７から射出された光Ｌ１１は、楔形導光棒１３９に入射し、楔形導光棒１３９の内部をｘ軸方向に伝播する。楔形導光棒１３９の内部を伝播する光Ｌ１１は、図２０に示すように、第１側面１３９ｂ（光射出面）と第２側面１３９ｃ（反射面）との間で反射を繰り返しつつ、楔形導光棒１３９の内部を光の伝播方向Ｘ（図２０の上側）に向けて進行する。仮に第１側面と第２側面とが平行であったとすると、光が反射を繰り返しても、第１側面および第２側面への光の入射角は変化しない。ところが、楔形導光棒１３９は端面１３９ａ側から離れるにつれて幅が徐々に狭くなっている。すなわち、第１側面１３９ｂに対して第２側面１３９ｃが所定の傾斜角を有している。そのため、光Ｌ１１は、第１側面１３９ｂおよび第２側面１３９ｃで反射する毎に第１側面１３９ｂおよび第２側面１３９ｃへの入射角が小さくなる。 Hereinafter, the operation of the surface light source device 135 having the above configuration will be described.
First, the light source unit 137 for high directivity will be described with reference to FIG.
The light L11 emitted from the first LED 17 enters the wedge-shaped light guide rod 139 and propagates in the x-axis direction through the inside of the wedge-shaped light guide rod 139. As shown in FIG. 20, the light L11 propagating through the inside of the wedge-shaped light guide rod 139 is repeatedly reflected between the first side surface 139b (light emitting surface) and the second side surface 139c (reflecting surface) while being guided by the wedge shape. The light rod 139 travels in the light propagation direction X (upper side in FIG. 20). If the first side surface and the second side surface are parallel to each other, the incident angle of the light to the first side surface and the second side surface does not change even if light is repeatedly reflected. However, the width of the wedge-shaped light guide bar 139 gradually decreases as the distance from the end face 139a side increases. That is, the second side surface 139c has a predetermined inclination angle with respect to the first side surface 139b. Therefore, each time the light L11 is reflected by the first side surface 139b and the second side surface 139c, the incident angle to the first side surface 139b and the second side surface 139c becomes small.
　ここで、例えば楔形導光棒１３９を構成するアクリル樹脂の屈折率が１．５、空気の屈折率を１．０とすると、楔形導光棒１３９の第１側面１３９ｂ（光射出面）における臨界角、すなわち楔形導光棒１３９を構成するアクリル樹脂と空気との界面における臨界角は、Ｓｎｅｌｌの法則から４２°程度となる。楔形導光棒１３９に入射した直後の光が第１側面１３９ｂに入射した際、第１側面１３９ｂへの光Ｌ１１の入射角が臨界角である４２°よりも大きい間は全反射条件を満たすため、光Ｌ１１は第１側面１３９ｂで全反射する。その後、光Ｌ１１が第１側面１３９ｂと第２側面１３９ｃとの間で反射を繰り返し、第１側面１３９ｂへの光Ｌ１１の入射角が臨界角である４２°よりも小さくなった時点で全反射条件を満たさなくなり、光Ｌ１１は第１側面１３９ｂから外部空間に射出される。 Here, for example, when the refractive index of the acrylic resin constituting the wedge-shaped light guide rod 139 is 1.5 and the refractive index of air is 1.0, the criticality at the first side surface 139b (light emission surface) of the wedge-shaped light guide rod 139 is determined. The critical angle at the interface between the acrylic resin and the air constituting the wedge-shaped light guide rod 139 is about 42 ° from Snell's law. When the light immediately after entering the wedge-shaped light guide rod 139 enters the first side surface 139b, the total reflection condition is satisfied as long as the incident angle of the light L11 on the first side surface 139b is larger than 42 ° which is a critical angle. The light L11 is totally reflected by the first side surface 139b. Thereafter, the light L11 is repeatedly reflected between the first side surface 139b and the second side surface 139c, and when the incident angle of the light L11 to the first side surface 139b becomes smaller than 42 ° which is a critical angle, the total reflection condition The light L11 is emitted from the first side surface 139b to the external space.
　すなわち、光Ｌ１１は、第１側面１３９ｂへの入射角が臨界角よりも大きい間は楔形導光棒１３９の内部に閉じ込められ、第１側面１３９ｂへの入射角が臨界角よりも小さくなった時点で第１側面１３９ｂから順次射出される。光Ｌ１１は第１側面１３９ｂから射出される際に屈折するので、第１側面１３９ｂへの入射角が４２°程度の光は、射出角が７０°程度の光となって射出される。このようにして、光の伝播方向Ｘに平行、かつ楔形導光棒１３９の光射出面３９ｂに垂直な平面（ｘｙ平面）内で見たとき、光Ｌ１は楔形導光棒１３９に入射した時点では指向性を持たないが、楔形導光棒１３９から射出する時点では高い指向性を有することになる。 That is, the light L11 is confined inside the wedge-shaped light guide rod 139 while the incident angle on the first side surface 139b is larger than the critical angle, and the incident angle on the first side surface 139b becomes smaller than the critical angle. Are sequentially ejected from the first side surface 139b. Since the light L11 is refracted when emitted from the first side surface 139b, light having an incident angle of about 42 ° to the first side surface 139b is emitted as light having an emission angle of about 70 °. In this way, when the light L1 enters the wedge-shaped light guide rod 139 when viewed in a plane (xy plane) parallel to the light propagation direction X and perpendicular to the light exit surface 39b of the wedge-shaped light guide rod 139. However, it does not have directivity, but has high directivity at the time of emission from the wedge-shaped light guide rod 139.
　楔形導光棒１３９から射出するときの光Ｌ１１の射出角は７０°程度であり、光Ｌ１１は楔形導光棒１３９の先端側に向けて射出される。したがって、入射角調整用プリズム１４０を用いて、楔形導光棒１３９から射出された光Ｌ１１を導光体１３の端面１３ａ（光入射端面）の法線方向に近い方向に立ち上げる。具体的には、先端角θ２が３８．５°程度のプリズム構造体１４１を有する入射角調整用プリズム１４０を用い、光Ｌ１１を、プリズム構造体１４１の第１面１４１ａから入射させ、第２面１４１ｂで反射させることで、導光体１３の端面１３ａに対して略法線方向に立ち上げることができる。このようにして、入射角調整用プリズム１４０は、高い指向性を保ったまま、導光体１３の端面１３ａに入射する光の入射角を調整することができる。 The emission angle of the light L11 when emitted from the wedge-shaped light guide rod 139 is about 70 °, and the light L11 is emitted toward the distal end side of the wedge-shaped light guide rod 139. Therefore, using the incident angle adjusting prism 140, the light L11 emitted from the wedge-shaped light guide rod 139 is raised in a direction close to the normal direction of the end face 13a (light incident end face) of the light guide 13. Specifically, using the incident angle adjusting prism 140 having the prism structure 141 with the tip angle θ2 of about 38.5 °, the light L11 is incident from the first surface 141a of the prism structure 141, and the second surface. By reflecting at 141 b, the light guide 13 can be raised in a substantially normal direction with respect to the end face 13 a. In this way, the incident angle adjusting prism 140 can adjust the incident angle of light incident on the end surface 13a of the light guide 13 while maintaining high directivity.
　一方、広角用光源部１３８については、図１８に示すように、第２のＬＥＤ１１５の発光面１１５ａから発せられた光Ｌ１２は、所定の拡散角をもって導光体１３に入射する。したがって、広角用光源部１３８から射出された光Ｌ１２の角度分布は、高指向性用光源部１３７から射出された光Ｌ１１の角度分布よりも広くなる。 On the other hand, as for the wide-angle light source unit 138, as shown in FIG. 18, the light L12 emitted from the light emitting surface 115a of the second LED 115 enters the light guide 13 with a predetermined diffusion angle. Therefore, the angular distribution of the light L12 emitted from the wide-angle light source unit 138 is wider than the angular distribution of the light L11 emitted from the high-directivity light source unit 137.
　以上をまとめると、高指向性用光源部１３７については、入射角調整用プリズム１４０から射出された時点において、光Ｌ１１は、導光体１３の光射出面１３ｂに平行な平面（ｘｙ平面）内でのみ高い指向性を持ち、導光体内部での光の伝播方向に平行、かつ導光体１３の光射出面１３ｂに垂直な平面（ｙｚ平面）内では指向性を持たない。このような光Ｌ１が、光入射面（端面）３ａから導光体１３に入射され、導光体１３の内部を伝播する。 In summary, in the light source unit 137 for high directivity, the light L11 is in a plane (xy plane) parallel to the light exit surface 13b of the light guide 13 when it is emitted from the incident angle adjusting prism 140. In the plane (yz plane) parallel to the light propagation direction inside the light guide and perpendicular to the light exit surface 13b of the light guide 13, it has no directivity. Such light L <b> 1 enters the light guide 13 from the light incident surface (end surface) 3 a and propagates inside the light guide 13.
　一方、広角用光源部１３８については、光Ｌ１は、導光体１３の光射出面１３ｂに平行な平面（ｘｙ平面）内、導光体１３の内部での光の伝播方向に平行、かつ導光体１３の光射出面１３ｂに垂直な平面（ｙｚ平面）内の双方で指向性を持たない。このような光Ｌ１が、導光体１３の内部を伝播する。 On the other hand, for the wide-angle light source unit 138, the light L1 is parallel to the light propagation direction in the plane (xy plane) parallel to the light exit surface 13b of the light guide 13 and inside the light guide 13. There is no directivity in both planes (yz plane) perpendicular to the light exit surface 13b of the light body 13. Such light L1 propagates in the light guide 13.
　以下、各光源部１３７，１３８からの光Ｌ１１，Ｌ１２が導光体１３およびプリズムシート１４０から外部空間に射出されるまでの振る舞いは、第１実施形態と同様である。本実施形態においても、第１実施形態と同様、高指向性用光源部１３７の第１のＬＥＤ５を点灯させることにより高指向性モードの照明が実現でき、広角用光源部１３８の第２のＬＥＤ１１５を点灯させることにより広角モードの照明が実現できる。また、第１のＬＥＤ１７と第２のＬＥＤ１１５とを同時に点灯させた場合、広角モードの照明が実現できる点も第１実施形態と同様である。 Hereinafter, the behavior until the lights L11 and L12 from the light source units 137 and 138 are emitted from the light guide 13 and the prism sheet 140 to the external space is the same as in the first embodiment. Also in the present embodiment, similarly to the first embodiment, lighting in the high directivity mode can be realized by turning on the first LED 5 of the light source unit 137 for high directivity, and the second LED 115 of the light source unit 138 for wide angle is realized. By turning on, wide-angle mode illumination can be realized. Moreover, when the 1st LED17 and the 2nd LED115 are lighted simultaneously, the point which can implement | achieve illumination of a wide angle mode is the same as that of 1st Embodiment.
　本実施形態においても、部品点数や製造コストの増大を招くことなく、指向性の切り替え前後で輝度を均一に保つことができる面光源装置が実現できる、という第１実施形態と同様の効果が得られる。 Also in this embodiment, the same effect as that of the first embodiment can be obtained that a surface light source device that can keep the luminance uniform before and after switching the directivity without increasing the number of parts and the manufacturing cost can be realized. It is done.
その他、本実施形態特有の効果として、以下の点が挙げられる。
　第１のＬＥＤ１７からの射出光に指向性を与える手段として、第１～第４実施形態のような凹面ミラー１９およびシリンドリカルレンズ１８を用いた場合、図２１の右側に示すように、凹面ミラー１９およびシリンドリカルレンズ１８の曲面形状に起因して、導光体内部の光の伝播方向（ｙ軸方向）の光源１６の寸法はある程度大きくなる。これに対して、本実施形態のような楔形導光棒１３９を用いた場合、図２１の左側に示すように、ｘ軸方向の寸法を同じにしたとしても、導光体内部の光の伝播方向（ｙ軸方向）の寸法を凹面ミラー１９の場合に比べて小さくすることができる。その結果、本実施形態によれば、面光源装置の小型化を図ることができる。 In addition, the following points can be cited as effects unique to the present embodiment.
When the concave mirror 19 and the cylindrical lens 18 as in the first to fourth embodiments are used as means for giving directivity to the light emitted from the first LED 17, as shown on the right side of FIG. Due to the curved surface shape of the cylindrical lens 18, the dimension of the light source 16 in the light propagation direction (y-axis direction) inside the light guide is increased to some extent. On the other hand, when the wedge-shaped light guide rod 139 as in this embodiment is used, even if the dimensions in the x-axis direction are the same as shown on the left side of FIG. The dimension in the direction (y-axis direction) can be made smaller than that of the concave mirror 19. As a result, according to this embodiment, it is possible to reduce the size of the surface light source device.
［第１変形例］
　上記実施形態の面光源装置は、高指向性用光源部として、第１のＬＥＤと楔形導光棒からなるユニットを１組備えていた。この構成に代えて、高指向性用光源部を図２２に示す構成としてもよい。
　本変形例の面光源装置１４３は、図２２に示すように、高指向性用光源部１３７として、第１のＬＥＤ１７と楔形導光棒１３９とからなるユニットを複数組備えている。本変形例では、３組のユニットを備えているが、ユニットの数は特に限定されない。 [First Modification]
The surface light source device of the said embodiment was provided with 1 set of units which consist of 1st LED and a wedge-shaped light guide rod as a high directivity light source part. Instead of this configuration, the light source unit for high directivity may be configured as shown in FIG.
As shown in FIG. 22, the surface light source device 143 according to the present modification includes a plurality of units each including a first LED 17 and a wedge-shaped light guide rod 139 as the light source unit 137 for high directivity. In this modification, three sets of units are provided, but the number of units is not particularly limited.
　本変形例の面光源装置１４３によれば、第１のＬＥＤ１７の数が上記実施形態の面光源装置に比べて多くなるため、高指向性用光源部１３７から射出される光の量を増やすことができる。 According to the surface light source device 143 of the present modification, the number of the first LEDs 17 is larger than that of the surface light source device of the above embodiment, and thus the amount of light emitted from the high directivity light source unit 137 is increased. Can do.
［第２変形例］
　上記実施形態では、第１のＬＥＤからの射出光に指向性を与える手段として、楔状導光棒１３９を用いたが、これに代えて、図２３に示す導光棒を用いてもよい。
　本変形例の高指向性用光源部１４５は、図２３に示すように、導光棒１４６と、導光棒１４６の長手方向の端面に設けられた第１のＬＥＤ１７と、を備えている。導光棒１４６は、第１側面１４６ｂ（光射出面）と対向する第２側面１４６ｃ側に複数のプリズム構造体１４７が設けられている。プリズム構造体１４７の平面形状は直角三角形状である。プリズム構造体１４７は、第１面１４７ａと、第１面１４７ａに対して所定の先端角をなす第２面１４７ｂと、を有している。第２面１４７ｂは、導光棒１４６の内部を伝播する光を反射させる反射面として機能する。 [Second Modification]
In the above embodiment, the wedge-shaped light guide rod 139 is used as means for giving directivity to the light emitted from the first LED. However, instead of this, the light guide rod shown in FIG. 23 may be used.
As shown in FIG. 23, the light source unit 145 for high directivity of the present modification includes a light guide bar 146 and a first LED 17 provided on the end surface of the light guide bar 146 in the longitudinal direction. The light guide rod 146 is provided with a plurality of prism structures 147 on the second side surface 146c facing the first side surface 146b (light emission surface). The planar shape of the prism structure 147 is a right triangle. The prism structure 147 includes a first surface 147a and a second surface 147b that forms a predetermined tip angle with respect to the first surface 147a. The second surface 147 b functions as a reflecting surface that reflects light propagating through the light guide rod 146.
　すなわち、楔状導光棒１３９が連続した一つの反射面を有するのに対し、本変形例の導光棒１４６は分割された複数の反射面を有する。したがって、本変形例の導光棒１４６も、楔状導光棒１３９と同様の作用により、射出光に高い指向性を与えることができる。 That is, the wedge-shaped light guide rod 139 has one continuous reflection surface, whereas the light guide rod 146 of this modification has a plurality of divided reflection surfaces. Therefore, the light guide bar 146 of this modification can also give high directivity to the emitted light by the same action as the wedge-shaped light guide bar 139.
［第６実施形態］
　以下、本発明の第６実施形態について、図２４、図２５Ａ、および図２５Ｂを用いて説明する。
　本実施形態の面光源装置の導光体の構成は第１実施形態と同様であり、光源部の構成が第１実施形態と異なる。
　図２４は、本実施形態の面光源装置における光源部を示す分解斜視図である。図２５Ａは、光源部の平面図である。図２５Ｂは、光源部の側面図である。
　図２４、図２５Ａ、及び図２５Ｂにおいて、第１実施形態で用いた図面と共通の構成要素には同一の符号を付し、説明を省略する。 [Sixth Embodiment]
Hereinafter, a sixth embodiment of the present invention will be described with reference to FIGS. 24, 25A, and 25B.
The configuration of the light guide of the surface light source device of this embodiment is the same as that of the first embodiment, and the configuration of the light source unit is different from that of the first embodiment.
FIG. 24 is an exploded perspective view showing a light source unit in the surface light source device of this embodiment. FIG. 25A is a plan view of the light source unit. FIG. 25B is a side view of the light source unit.
24, FIG. 25A, and FIG. 25B, the same code | symbol is attached | subjected to the same component as drawing used in 1st Embodiment, and description is abbreviate | omitted.
　本実施形態の面光源装置１４９において、光源部１５０は、図２４、図２５Ｂに示すように、導光体１３の厚さ方向（ｚ軸方向）に積層された高指向性用光源部１５１（第１の光源部）と広角用光源部１５２（第２の光源部）とから構成されている。本実施形態では、下段に高指向性用光源部１５１が配置され、上段に広角用光源部１５２が配置されている。ただし、これとは逆に、下段に広角用光源部１５２が配置され、上段に高指向性用光源部１５１が配置されていてもよい。 In the surface light source device 149 of the present embodiment, the light source unit 150 includes a highly directional light source unit 151 (stacked in the thickness direction (z-axis direction) of the light guide 13 (see FIG. 24 and FIG. 25B). The first light source unit) and a wide-angle light source unit 152 (second light source unit). In the present embodiment, the light source unit 151 for high directivity is arranged at the lower stage, and the light source unit 152 for wide angle is arranged at the upper stage. However, conversely, the wide-angle light source unit 152 may be disposed in the lower stage, and the high directivity light source unit 151 may be disposed in the upper stage.
　高指向性用光源部１５１は、図２４、図２５Ａに示すように、第１のＬＥＤ１７（第１の発光素子）と、楔形導光棒１３９（反射素子）と、入射角調整用プリズム１４０と、を備えている。すなわち、高指向性用光源部１５１の構成は第５実施形態と同一である。 As shown in FIGS. 24 and 25A, the high directivity light source unit 151 includes a first LED 17 (first light emitting element), a wedge-shaped light guide bar 139 (reflective element), and an incident angle adjusting prism 140. It is equipped with. That is, the configuration of the high directivity light source unit 151 is the same as that of the fifth embodiment.
　広角用光源部１５２は、第２のＬＥＤ１１５（第２の発光素子）と、楔形導光棒１３９（反射素子）と、光散乱部材１５３と、を備えている。第２のＬＥＤ１１５と楔形導光棒１３９とを備えただけの構成では、光の射出方向こそ異なるものの、高指向性用光源部１５１と同様に高い指向性の光が得られることになる。そこで、広角用光源部１５２においては、楔形導光棒１３９の光射出側に光散乱部材１５３が配置されている。光散乱部材１５３は、表面に光を散乱させるための加工が施された光透過性の部材である。光を散乱させるための加工は、具体的には印刷、研磨、凹凸形状の付与等の手法により行われている。なお、光散乱部材１５３の散乱特性は、前方散乱する光の割合をできるだけ多くし、後方散乱する光の割合をできるだけ少なくするように調整されることが望ましい。 The wide-angle light source unit 152 includes a second LED 115 (second light emitting element), a wedge-shaped light guide rod 139 (reflective element), and a light scattering member 153. In the configuration in which only the second LED 115 and the wedge-shaped light guide bar 139 are provided, light having a high directivity can be obtained in the same manner as the light source unit 151 for high directivity although the light emission direction is different. Therefore, in the wide-angle light source unit 152, the light scattering member 153 is disposed on the light emission side of the wedge-shaped light guide bar 139. The light scattering member 153 is a light-transmitting member that has been processed to scatter light on the surface. Specifically, the processing for scattering the light is performed by a technique such as printing, polishing, or providing an uneven shape. Note that it is desirable that the scattering characteristics of the light scattering member 153 be adjusted so that the proportion of light that is scattered forward is increased as much as possible, and the proportion of light that is scattered backward is minimized.
　高指向性用光源部１５１と広角用光源部１５２とは、第１のＬＥＤ１７と第２のＬＥＤ１１５とが反対側に位置するように配置されている。したがって、高指向性用光源部１５１、広角用光源部１５２の各々の楔形導光棒１３９も逆向きに配置されている。この構成であれば、第１のＬＥＤ１７に電流を供給する配線（図示略）と第２のＬＥＤ１１５に電流を供給する配線（図示略）が干渉しないため、好ましい。ただし、第１のＬＥＤ１７と第２のＬＥＤ１１５とが同じ側に位置してもよい。 The light source unit 151 for high directivity and the light source unit 152 for wide angle are arranged so that the first LED 17 and the second LED 115 are located on the opposite sides. Therefore, the wedge-shaped light guide rods 139 of the high directivity light source 151 and the wide-angle light source 152 are also arranged in opposite directions. This configuration is preferable because the wiring (not shown) for supplying current to the first LED 17 and the wiring (not shown) for supplying current to the second LED 115 do not interfere with each other. However, the first LED 17 and the second LED 115 may be located on the same side.
　この構成によれば、広角用光源部１５２において、楔形導光棒１３９の第１側面１３９ｂから射出された光は、光散乱部材１５３を透過するときに散乱されて射出される。よって、最終的に広角用光源部１５２から射出される光の角度分布は、高指向性用光源部１５１から射出される光の角度分布に比べて広くなる。
　本実施形態の「光散乱部材」は、特許請求の範囲の「角度分布変換部材」に相当する。
ただし、第１～第５実施形態で用いられた各種の角度分布変換部材は指向性が低い光を入射させ、その光の指向性を高くする方向に機能する。これに対して、本実施形態の光散乱部材１５３は、指向性が高い光を入射させ、その光の指向性を低下させる方向に機能する。 According to this configuration, the light emitted from the first side surface 139 b of the wedge-shaped light guide rod 139 in the wide-angle light source unit 152 is scattered and emitted when passing through the light scattering member 153. Therefore, the angular distribution of light finally emitted from the wide-angle light source unit 152 is wider than the angular distribution of light emitted from the high-directivity light source unit 151.
The “light scattering member” in the present embodiment corresponds to an “angle distribution conversion member” in the claims.
However, the various angle distribution conversion members used in the first to fifth embodiments function in a direction in which light having low directivity is incident and the directivity of the light is increased. On the other hand, the light scattering member 153 of this embodiment functions in a direction in which light having high directivity is incident and the directivity of the light is reduced.
　本実施形態においても、部品点数や製造コストの増大を招くことなく、指向性の切り替え前後で輝度を均一に保つことができる面光源装置が実現できる、という第１実施形態と同様の効果が得られる。 Also in this embodiment, the same effect as that of the first embodiment can be obtained that a surface light source device that can keep the luminance uniform before and after switching the directivity without increasing the number of parts and the manufacturing cost can be realized. It is done.
［第１変形例］
　上記実施形態の面光源装置は、高指向性用光源部として、第１のＬＥＤと楔形導光棒とからなるユニットを１組備え、広角用光源部として、第１のＬＥＤと楔形導光棒と光散乱部材とからなるユニットを１組備えていた。この構成に代えて、光源部を図２６に示す構成としてもよい。
　本変形例の面光源装置１５５は、図２６に示すように、高指向性用光源部１５１として、第１のＬＥＤ１７と楔形導光棒１３９とからなるユニットを複数組備えている。また、広角用光源部１５２として、第２のＬＥＤ１１５と楔形導光棒１３９と光散乱部材１５３とからなるユニットを複数組備えている。本変形例では、各光源部１５１，１５２とも３組のユニットを備えているが、ユニットの数は特に限定されない。 [First Modification]
The surface light source device of the above-described embodiment includes a set of units each including a first LED and a wedge-shaped light guide bar as a high directivity light source unit, and the first LED and a wedge-shaped light guide bar as a wide-angle light source unit. And a unit consisting of a light scattering member. Instead of this configuration, the light source unit may be configured as shown in FIG.
As shown in FIG. 26, the surface light source device 155 of the present modification includes a plurality of units each including the first LED 17 and a wedge-shaped light guide bar 139 as the high directivity light source unit 151. The wide-angle light source unit 152 includes a plurality of units each including a second LED 115, a wedge-shaped light guide rod 139, and a light scattering member 153. In this modification, each of the light source units 151 and 152 includes three sets of units, but the number of units is not particularly limited.
　本変形例の面光源装置１５５によれば、ＬＥＤの数が上記実施形態の面光源装置に比べて多くなるため、各光源部から射出される光の量を増やすことができる。 According to the surface light source device 155 of the present modification, the number of LEDs is increased as compared with the surface light source device of the above embodiment, and thus the amount of light emitted from each light source unit can be increased.
［第７実施形態］
　以下、本発明の第７実施形態について、図２７Ａおよび図２７Ｂを用いて説明する。
　本実施形態の面光源装置の導光体の構成は第１実施形態と同様であり、光源部の構成が第１実施形態と異なる。
　図２７Ａは、本実施形態の面光源装置における光源部を示す平面図である。図２７Ｂは、光源部の側面図である。
　図２７Ａ、図２７Ｂにおいて、上記実施形態で用いた図面と共通の構成要素には同一の符号を付し、説明を省略する。 [Seventh Embodiment]
Hereinafter, a seventh embodiment of the present invention will be described with reference to FIGS. 27A and 27B.
The configuration of the light guide of the surface light source device of this embodiment is the same as that of the first embodiment, and the configuration of the light source unit is different from that of the first embodiment.
FIG. 27A is a plan view showing a light source unit in the surface light source device of the present embodiment. FIG. 27B is a side view of the light source unit.
In FIG. 27A and FIG. 27B, the same code | symbol is attached | subjected to the same component as drawing used in the said embodiment, and description is abbreviate | omitted.
　本実施形態の面光源装置１５７において、光源部１５８は、図２７Ａ及び図２７Ｂに示すように、複数の高指向性用光源部１５９（第１の光源部）と複数の広角用光源部１６０（第２の光源部）とを備えている。複数の高指向性用光源部１５９および複数の広角用光源部１６０は、導光体１３の内部の光の伝播方向Ｙに垂直な方向（ｘ軸方向）に沿って交互に配置されている。 In the surface light source device 157 of the present embodiment, the light source unit 158 includes a plurality of high directivity light source units 159 (first light source units) and a plurality of wide angle light source units 160 (see FIG. 27A and FIG. 27B). 2nd light source part). The plurality of high directivity light source units 159 and the plurality of wide angle light source units 160 are alternately arranged along a direction (x-axis direction) perpendicular to the light propagation direction Y inside the light guide 13.
　図２７Ａに示すように、高指向性用光源部１５９は、第１のＬＥＤ１７（第１の発光素子）と、平行化レンズ（角度分布変換部材ともいう）１６１と、を備えている。第１のＬＥＤ１７には、拡散光を射出する一般のＬＥＤを用いることができる。平行化レンズ１６１は、第１のＬＥＤ１７から射出された光を略平行化する機能を有する。平行化レンズ１６１は、導光体１３の端面１３ａに接するように配置されている。第１のＬＥＤ１７は、平行化レンズ１６１の焦点距離分だけ平行化レンズ１６１から離れた位置に配置されている。　 As shown in FIG. 27A, the light source unit 159 for high directivity includes a first LED 17 (first light emitting element) and a collimating lens (also referred to as an angle distribution converting member) 161. As the first LED 17, a general LED that emits diffused light can be used. The collimating lens 161 has a function of substantially collimating the light emitted from the first LED 17. The collimating lens 161 is disposed in contact with the end surface 13 a of the light guide 13. The first LED 17 is disposed at a position separated from the collimating lens 161 by the focal length of the collimating lens 161. *
　広角用光源部１６０は、第２のＬＥＤ１１５（第２の発光素子）を備えている。第２のＬＥＤ１１５には、拡散光を射出する一般のＬＥＤを用いることができる。第２のＬＥＤ１１５は、発光面が導光体１３の端面１３ａに接するように配置されている。 The wide-angle light source unit 160 includes a second LED 115 (second light emitting element). As the second LED 115, a general LED that emits diffused light can be used. The second LED 115 is disposed such that the light emitting surface is in contact with the end surface 13 a of the light guide 13.
　高指向性モードにおいては、第１のＬＥＤ１７を点灯させると、第１のＬＥＤ１７から射出された光Ｌ１１が平行化レンズ１６１によって略平行化され、導光体１３に入射される。広角モードにおいては、第２のＬＥＤ１１５を点灯させると、第２のＬＥＤ１１５から射出された拡散光Ｌ１２が導光体１３に入射される。広角モードにおいては、第１のＬＥＤ１７、第２のＬＥＤ１１５の双方を点灯させてもよい。 In the high directivity mode, when the first LED 17 is turned on, the light L11 emitted from the first LED 17 is substantially collimated by the collimating lens 161 and is incident on the light guide 13. In the wide-angle mode, when the second LED 115 is turned on, the diffused light L12 emitted from the second LED 115 is incident on the light guide 13. In the wide angle mode, both the first LED 17 and the second LED 115 may be lit.
　本実施形態においても、部品点数や製造コストの増大を招くことなく、指向性の切り替え前後で輝度を均一に保つことができる面光源装置が実現できる、という第１実施形態と同様の効果が得られる。 Also in this embodiment, the same effect as that of the first embodiment can be obtained that a surface light source device that can keep the luminance uniform before and after switching the directivity without increasing the number of parts and the manufacturing cost can be realized. It is done.
［第８実施形態］
　以下、本発明の第８実施形態について、図２８Ａ～図３０Ｃを用いて説明する。
　本実施形態の面光源装置の構成は、第１実施形態の第２変形例の図９に示す面光源装置と略同様である。
　図２８Ａは、本実施形態の面光源装置を示す平面図である。図２８Ｂは、図２８ＡのＡ－Ａ’線に沿う断面図である。図２９Ａ～図２９Ｃは、本実施形態の面光源装置における照度分布のシミュレーション結果を示す図である。図３０Ａ～図３０Ｃは、比較例の面光源装置における照度分布のシミュレーション結果を示す図である。
　図２８Ａ、図２８Ｂにおいて、図９と共通の構成要素には同一の符号を付し、説明を省略する。 [Eighth Embodiment]
The eighth embodiment of the present invention will be described below with reference to FIGS. 28A to 30C.
The configuration of the surface light source device of the present embodiment is substantially the same as the surface light source device shown in FIG. 9 of the second modification of the first embodiment.
FIG. 28A is a plan view showing the surface light source device of this embodiment. 28B is a cross-sectional view taken along the line AA ′ of FIG. 28A. 29A to 29C are diagrams showing simulation results of the illuminance distribution in the surface light source device of this embodiment. 30A to 30C are diagrams illustrating simulation results of illuminance distribution in the surface light source device of the comparative example.
28A and 28B, the same components as those in FIG. 9 are denoted by the same reference numerals, and description thereof is omitted.
　本実施形態の面光源装置１８１は、図２８Ａ及び図２８Ｂに示すように、第１主面１８２ｂ（光射出面）と第２主面１８２ｃとが平行な平行平板からなる導光体１８２を備えている。導光体１８２の第１主面１８２ｂには、光の伝播方向Ｙと垂直な方向（ｘ軸方向）に延在する複数の光取り出し用プリズム１８３が所定の間隔をおいて設けられている。光取り出し用プリズム１８３は、導光体１８２と同じ屈折率を有する材料で構成されることが望ましい。光取り出し用プリズム１８３の断面形状は、導光体１８２の第１主面１８２ｂに接する側の幅が狭く、第１主面１８２ｂと反対側の幅が広い形状、いわゆる逆テーパ形状である。 As shown in FIGS. 28A and 28B, the surface light source device 181 of the present embodiment includes a light guide 182 made of parallel flat plates in which a first main surface 182b (light emission surface) and a second main surface 182c are parallel. ing. A plurality of light extraction prisms 183 extending in a direction perpendicular to the light propagation direction Y (x-axis direction) are provided on the first main surface 182b of the light guide 182 at a predetermined interval. The light extraction prism 183 is preferably made of a material having the same refractive index as that of the light guide 182. The cross-sectional shape of the light extraction prism 183 is a so-called reverse taper shape in which the width on the side in contact with the first main surface 182b of the light guide 182 is narrow and the width on the side opposite to the first main surface 182b is wide.
　複数の光取り出し用プリズム１８３は、等間隔に配置されていない。すなわち、複数の光取り出し用プリズム１８３は、光源部１２が設けられた導光体１８２の端面１８２ａに近いほど密度が低く、端面１８２ａから遠いほど密度が高くなるように設けられている。光源部１２から射出された光Ｌ１は、導光体１８２の内部を伝播する間に、複数の光取り出し用プリズム１８３のうちのいずれかに入射する。光取り出し用プリズム１８３に入射した光Ｌ１は、反射面１８３ａで反射した後、角度を変え、導光体１８２の外部に取り出される。 The plurality of light extraction prisms 183 are not arranged at equal intervals. That is, the plurality of light extraction prisms 183 are provided such that the closer to the end surface 182a of the light guide 182 provided with the light source unit 12, the lower the density and the farther from the end surface 182a, the higher the density. The light L <b> 1 emitted from the light source unit 12 is incident on one of the plurality of light extraction prisms 183 while propagating through the light guide 182. The light L1 that has entered the light extraction prism 183 is reflected by the reflection surface 183a, and then the angle is changed, and the light L1 is extracted to the outside of the light guide 182.
　本実施形態の面光源装置１８１においても、部品点数や製造コストの増大を招くことなく、指向性の切り替え前後で輝度を均一に保つことができる面光源装置が実現できる、という第１実施形態と同様の効果が得られる。 Also in the surface light source device 181 of the present embodiment, the surface light source device that can keep the luminance uniform before and after switching the directivity without increasing the number of parts and the manufacturing cost can be realized. Similar effects can be obtained.
　特に本実施形態の場合、高指向性用光源部１１３と広角用光源部１１４とが導光体１８２の一つの端面１８２ａに配置されているため、以下の効果を得ることができる。
　一般に、導光体の端面に光源を配置した場合、光の取り出し量は、導光体の光射出面のうち、光源に近い側で多く、光源に遠い側では少ない傾向を示す。したがって、導光体の光射出面での照度分布が不均一になる。そこで、本実施形態のように、複数の光取り出し用プリズム１８３を、導光体１８２の端面１８２ａに近いほど密度が低く、端面１８２ａから遠いほど密度が高くなるように配置することで、照度分布をより均一にすることができる。 In particular, in the case of the present embodiment, the high directivity light source unit 113 and the wide-angle light source unit 114 are arranged on one end surface 182a of the light guide 182. Therefore, the following effects can be obtained.
In general, when a light source is arranged on the end face of the light guide, the amount of light extraction tends to be large on the light exit surface of the light guide near the light source and small on the side far from the light source. Therefore, the illuminance distribution on the light exit surface of the light guide becomes non-uniform. Therefore, as in the present embodiment, the plurality of light extraction prisms 183 are arranged such that the density is lower as the distance from the end face 182a of the light guide 182 is lower, and the density is higher as the distance from the end face 182a is higher. Can be made more uniform.
　ここで、例えば特許文献３に記載の照明装置のように、導光体の異なる端面に２つの光源部が配置されていたとすると、照度分布を均一にするための複数の光取り出し用プリズム１８３の配置がいずれか一方の光源部に対してしか働かない。これに対し、本実施形態の面光源装置１８１では、高指向性用光源部１１３と広角用光源部１１４とが導光体１８２の一つの端面１８２ａに配置され、指向性の切り替え前後で光の伝播方向Ｙが変わらない。そのため、照度分布を均一にするための複数の光取り出し用プリズム１８３の配置がどちらの光源部１１３，１１４に対しても有効に働く。したがって、指向性の切り替え前後で照度分布を均一に保ちやすくなる。 Here, for example, as in the illumination device described in Patent Document 3, if two light source units are arranged on different end faces of the light guide, a plurality of light extraction prisms 183 for making the illuminance distribution uniform can be obtained. The arrangement only works for one of the light source sections. On the other hand, in the surface light source device 181 of this embodiment, the light source unit for high directivity 113 and the light source unit for wide angle 114 are arranged on one end surface 182a of the light guide 182 so that light can be transmitted before and after switching the directivity. The propagation direction Y does not change. Therefore, the arrangement of the plurality of light extraction prisms 183 for making the illuminance distribution uniform works effectively for both light source units 113 and 114. Therefore, it is easy to keep the illuminance distribution uniform before and after switching the directivity.
　本発明者らは、本実施形態の面光源装置と比較例の面光源装置に対して、光射出面での照度分布についてシミュレーションを行った。
　シミュレーションには、照明設計解析ソフトウェア：Light Tools(ver7.2)を用いた。
シミュレーションの条件は第１実施形態と同様に設定した。 The inventors performed a simulation on the illuminance distribution on the light exit surface of the surface light source device of this embodiment and the surface light source device of the comparative example.
For the simulation, lighting design analysis software: Light Tools (ver. 7.2) was used.
The simulation conditions were set in the same manner as in the first embodiment.
　図２９Ａは、本実施形態の面光源装置を示しており、高指向性用光源部１１３と広角用光源部１１４とからの光を、導光体１８２の一つの端面１８２ａから入射させている。図２９Ｂは、高指向性用光源部１１３からの光による照度分布を示し、図２９Ｃは、広角用光源部１１４からの光による照度分布を示している。 FIG. 29A shows the surface light source device of the present embodiment, in which light from the high directivity light source unit 113 and the wide angle light source unit 114 is incident from one end surface 182 a of the light guide 182. FIG. 29B shows the illuminance distribution by light from the light source unit 113 for high directivity, and FIG. 29C shows the illuminance distribution by light from the light source unit 114 for wide angle.
　図２９Ａおよび図２９Ｂに示すように、今回のシミュレーションでは、複数の光取り出し用プリズム１８３の配置が充分に最適化されておらず、照度分布が充分に均一化できなかった。しかしながら、本実施形態の面光源装置では、指向性の切り替え前後で照度分布がほとんど変化しないことが確認された。したがって、複数の光取り出し用プリズム１８３の配置が充分に最適化されれば、高指向性モードにおいても広角モードにおいても、照度分布が充分に均一化できる感触を得た。 As shown in FIGS. 29A and 29B, in this simulation, the arrangement of the plurality of light extraction prisms 183 was not sufficiently optimized, and the illuminance distribution could not be sufficiently uniformed. However, in the surface light source device of this embodiment, it has been confirmed that the illuminance distribution hardly changes before and after switching the directivity. Therefore, if the arrangement of the plurality of light extraction prisms 183 is sufficiently optimized, the illuminance distribution can be sufficiently uniformed in both the high directivity mode and the wide angle mode.
　これに対して、図３０Ａは、比較例の面光源装置を示しており、高指向性用光源部からの光を導光体１８２の端面１８２ａから入射させ、広角用光源部からの光を導光体１８２の端面１８２ｄから入射させている。図３０Ｂは、広角用光源部からの光による照度分布を示している。 On the other hand, FIG. 30A shows a surface light source device of a comparative example, in which light from the light source unit for high directivity is incident from the end surface 182a of the light guide 182 to guide light from the light source unit for wide angle. Incident light is incident from the end face 182d of the light body 182. FIG. 30B shows an illuminance distribution by light from the wide-angle light source unit.
　比較例の面光源装置では、端面１８２ａに配置された高指向性用光源部からの光に対して、光取り出し用プリズム１８３の配置が最適化されている。したがって、広角用光源部からの光に対しては、図３０Ｂに示すように、高指向性用光源部に近い側で光の取り出し量が多く、光源に遠い側では光の取り出し量が少なくなった。このように、比較例の面光源装置では、指向性の切り替え前後で照度分布が大きく変化し、いずれか一方のモードで照度分布が不均一になることが判った。 In the surface light source device of the comparative example, the arrangement of the light extraction prism 183 is optimized with respect to the light from the light source unit for high directivity arranged on the end surface 182a. Therefore, for the light from the wide-angle light source unit, as shown in FIG. 30B, the light extraction amount is large on the side close to the high directivity light source unit, and the light extraction amount is small on the side far from the light source. It was. Thus, in the surface light source device of the comparative example, it was found that the illuminance distribution changed greatly before and after the switching of directivity, and the illuminance distribution became non-uniform in either one of the modes.
　［第９実施形態］
　図３２Ａおよび図３２Ｂは、調光装置の第９実施形態を示す概略図であり、図３２Ａは平面図、図３２Ｂは図３２ＡのＡ２－Ａ２線に沿う断面図である。
　調光装置２１０は、光源部２１１と、導光体２１２と、散乱液晶セル２１３と、反射ミラー２１４を備えたパラボラミラー形状のレンズ２１５と、から概略構成されている。導光体２１２は、光源部２１１に対向して配置されている。導光体２１２は、光源部２１１からの光がその一端面２１２ａ側から導入されるとともに、光源部２１１からの光をその長手方向に導光する。散乱液晶セル２１３は、光源部２１１と導光体２１２の一端面２１２ａとの間に設けられる。パラボラミラー形状のレンズ２１５は、光源部２１１の導光体２１２の一端面２１２ａと対向する面２１１ａとは反対の面側に設けられる。反射ミラー２１４は、光源部２１１からの光を反射する反射面２１４ａを有する。
　本実施形態では、光源部２１１からの光の指向性を変化させる配光変換素子として、散乱液晶セル２１３を用いている。本実施形態の配光変換素子は、光源部からの光の指向性を変化させるという配光特性が可変である。以下に配光変換素子の構成について説明する。 [Ninth Embodiment]
32A and 32B are schematic views showing a ninth embodiment of the light control device, FIG. 32A is a plan view, and FIG. 32B is a cross-sectional view taken along the line A2-A2 of FIG. 32A.
The light control device 210 is generally configured by a light source unit 211, a light guide 212, a scattering liquid crystal cell 213, and a parabolic mirror-shaped lens 215 including a reflection mirror 214. The light guide 212 is disposed to face the light source unit 211. The light guide 212 introduces light from the light source unit 211 from the one end face 212a side, and guides light from the light source unit 211 in the longitudinal direction. The scattering liquid crystal cell 213 is provided between the light source unit 211 and the one end surface 212 a of the light guide 212. The parabolic mirror-shaped lens 215 is provided on the surface opposite to the surface 211 a facing the one end surface 212 a of the light guide 212 of the light source unit 211. The reflection mirror 214 has a reflection surface 214 a that reflects light from the light source unit 211.
In this embodiment, the scattering liquid crystal cell 213 is used as a light distribution conversion element that changes the directivity of light from the light source unit 211. The light distribution conversion element of this embodiment has a variable light distribution characteristic of changing the directivity of light from the light source unit. The configuration of the light distribution conversion element will be described below.
　散乱液晶セル２１３は、図３３に示すように、高分子分散液晶２２１と、高分子分散液晶２２１を挟持する一対の透明導電基板２２２，２２３とから概略構成されている。
　透明導電基板２２２は、透明基板２２４と、その一方の面２２４ａに設けられた透明導電膜２２５とから概略構成されている。
　透明導電基板２２３は、透明基板２２６と、その一方の面２２６ａに設けられた透明導電膜２２７とから概略構成されている。 As shown in FIG. 33, the scattering liquid crystal cell 213 is roughly composed of a polymer dispersed liquid crystal 221 and a pair of transparent conductive substrates 222 and 223 that sandwich the polymer dispersed liquid crystal 221.
The transparent conductive substrate 222 is roughly composed of a transparent substrate 224 and a transparent conductive film 225 provided on one surface 224a thereof.
The transparent conductive substrate 223 is roughly composed of a transparent substrate 226 and a transparent conductive film 227 provided on one surface 226a thereof.
　ここで、図３４Ａおよび図３４Ｂを参照して、散乱液晶セル２１３を構成する高分子分散液晶２２１としてノーマルモード高分子分散液晶を用いた場合について説明する。
　図３４Ａに示すように、透明導電基板２２２，２２３の間に電圧を印加していない場合、液晶２３１は配向することなく、ランダムポリマー３２と同様に散乱した状態をなしている。したがって、透明導電基板２２３側から散乱液晶セル２１３に入射した光は、液晶２３１によって散乱されて、散乱液晶セル２１３から散乱光となって出射する。
　一方、図３４Ｂに示すように、透明導電基板２２２，２２３の間に電圧を印加した場合、液晶２３１は散乱液晶セル２１３の厚さ方向に配向するので、散乱液晶セル２１３は透明になる。したがって、透明導電基板２２３側から散乱液晶セル２１３に入射した光は、液晶２３１によって散乱されることなく、散乱液晶セル２１３から指向性を有する光（散乱液晶セル２１３の厚さ方向の指向性を有する光）となって出射する。 Here, with reference to FIG. 34A and FIG. 34B, the case where a normal mode polymer dispersed liquid crystal is used as the polymer dispersed liquid crystal 221 constituting the scattering liquid crystal cell 213 will be described.
As shown in FIG. 34A, when a voltage is not applied between the transparent conductive substrates 222 and 223, the liquid crystal 231 is not oriented and is scattered like the random polymer 32. Therefore, the light incident on the scattering liquid crystal cell 213 from the transparent conductive substrate 223 side is scattered by the liquid crystal 231 and is emitted from the scattering liquid crystal cell 213 as scattered light.
On the other hand, as shown in FIG. 34B, when a voltage is applied between the transparent conductive substrates 222 and 223, the liquid crystal 231 is aligned in the thickness direction of the scattering liquid crystal cell 213, so that the scattering liquid crystal cell 213 becomes transparent. Therefore, the light incident on the scattering liquid crystal cell 213 from the transparent conductive substrate 223 side is not scattered by the liquid crystal 231 and has directivity from the scattering liquid crystal cell 213 (the directivity in the thickness direction of the scattering liquid crystal cell 213). Light).
　また、図３５をＡおよび図３５Ｂ参照して、散乱液晶セル２１３を構成する高分子分散液晶２２１としてリバースモード高分子分散液晶を用いた場合について説明する。
　図３５Ａに示すように、透明導電基板２２２，２２３の間に電圧を印加していない場合、液晶２４１は、液晶ポリマー２４３とともに、散乱液晶セル２１３の厚さ方向と垂直な方向に配向するので、散乱液晶セル２１３は透明になる。したがって、透明導電基板２２３側から散乱液晶セル２１３に入射した光は、液晶２４１や液晶ポリマー２４３によって散乱されることなく、散乱液晶セル２１３から指向性を有する光（散乱液晶セル２１３の厚さ方向の指向性を有する光）となって出射する。
　一方、図３５Ｂに示すように、透明導電基板２２２，２２３の間に電圧を印加した場合、液晶２４１は散乱液晶セル２１３の厚さ方向に配向し、ランダムポリマー２４２や液晶ポリマー２４３とは異なる方向に配向した状態をなす。したがって、透明導電基板２２３側から散乱液晶セル２１３に入射した光は、液晶２４１、ランダムポリマー２４２および液晶ポリマー２４３によって散乱されて、散乱液晶セル２１３から散乱光となって出射する。 A case where a reverse mode polymer dispersed liquid crystal is used as the polymer dispersed liquid crystal 221 constituting the scattering liquid crystal cell 213 will be described with reference to FIG. 35A and FIG. 35B.
As shown in FIG. 35A, when no voltage is applied between the transparent conductive substrates 222 and 223, the liquid crystal 241 is aligned with the liquid crystal polymer 243 in a direction perpendicular to the thickness direction of the scattering liquid crystal cell 213. The scattering liquid crystal cell 213 becomes transparent. Therefore, the light incident on the scattering liquid crystal cell 213 from the transparent conductive substrate 223 side is not scattered by the liquid crystal 241 or the liquid crystal polymer 243, and has directivity from the scattering liquid crystal cell 213 (in the thickness direction of the scattering liquid crystal cell 213). Of light having a directivity of 2).
On the other hand, as shown in FIG. 35B, when a voltage is applied between the transparent conductive substrates 222 and 223, the liquid crystal 241 is oriented in the thickness direction of the scattering liquid crystal cell 213 and is different from the random polymer 242 and the liquid crystal polymer 243. In an oriented state. Therefore, light incident on the scattering liquid crystal cell 213 from the transparent conductive substrate 223 side is scattered by the liquid crystal 241, the random polymer 242 and the liquid crystal polymer 243, and is emitted from the scattering liquid crystal cell 213 as scattered light.
　図３６Ａおよび図３６Ｂは、図３４Ｂに示すように、散乱液晶セル２１３を構成する液晶２３１を配向させるか、あるいは、図３５Ａに示すように、散乱液晶セル２１３を構成する液晶２４１を配向させて、調光装置２１０を用いた場合を説明する概略図である。図３６Ａは、平面図である。図３６Ｂは、導光体の一端面側から見た正面図である。
　このとき、光源部２１１からの光が、反射ミラー２１４の反射面２１４ａで反射して、その反射光が、散乱液晶セル２１３に入射すると、反射光は散乱液晶セル２１３内の液晶によって散乱されることなく、指向性を有する光として、一端面２１２ａから導光体２１２に入射する。
　したがって、導光体２１２の上面２１２ｂから出射する光は、導光体２１２の幅方向に拡がることなく、狭い出射角で出射する。導光体２１２の上面２１２ｂから出射する光の出射角は、例えば、図６の破線で示すように、極めて狭くなる。 36A and 36B, the liquid crystal 231 constituting the scattering liquid crystal cell 213 is oriented as shown in FIG. 34B, or the liquid crystal 241 constituting the scattering liquid crystal cell 213 is oriented as shown in FIG. 35A. It is the schematic explaining the case where the light control apparatus 210 is used. FIG. 36A is a plan view. FIG. 36B is a front view seen from one end surface side of the light guide.
At this time, when the light from the light source unit 211 is reflected by the reflection surface 214 a of the reflection mirror 214 and the reflected light enters the scattering liquid crystal cell 213, the reflected light is scattered by the liquid crystal in the scattering liquid crystal cell 213. Without incident, light having directivity enters the light guide 212 from the one end surface 212a.
Therefore, the light emitted from the upper surface 212 b of the light guide 212 is emitted at a narrow emission angle without spreading in the width direction of the light guide 212. The emission angle of the light emitted from the upper surface 212b of the light guide 212 is extremely narrow, for example, as shown by the broken line in FIG.
　また、図３７Ａおよび図３７Ｂは、図３４Ａに示すように、散乱液晶セル２１３を構成する液晶２３１が配向させない状態、あるいは、図３５Ｂに示すように、散乱液晶セル２１３を構成する液晶２４１を配向させない状態で、調光装置２１０を用いた場合を説明する概略図である。図３７Ａ、は平面図である。図３７Ｂは、導光体の一端面側から見た正面図である。
　このとき、光源部２１１からの光が、反射ミラー２１４の反射面２１４ａで反射して、その反射光が、散乱液晶セル２１３に入射すると、反射光は散乱液晶セル２１３内の液晶によって散乱され、散乱光となって、一端面２１２ａから導光体２１２に入射する。したがって、導光体２１２の上面２１２ｂから出射する光は、導光体２１２の幅方向に拡がり、広い出射角で出射する。導光体２１２の上面２１２ｂから出射する光の出射角は、例えば、図６の実線で示すように、広くなる。 37A and 37B show a state where the liquid crystal 231 constituting the scattering liquid crystal cell 213 is not oriented as shown in FIG. 34A, or the liquid crystal 241 constituting the scattering liquid crystal cell 213 is oriented as shown in FIG. 35B. It is the schematic explaining the case where the light control apparatus 210 is used in the state which is not made. FIG. 37A is a plan view. FIG. 37B is a front view seen from one end surface side of the light guide.
At this time, when the light from the light source unit 211 is reflected by the reflecting surface 214a of the reflecting mirror 214 and the reflected light enters the scattering liquid crystal cell 213, the reflected light is scattered by the liquid crystal in the scattering liquid crystal cell 213, It becomes scattered light and enters the light guide 212 from the one end face 212a. Therefore, the light emitted from the upper surface 212b of the light guide 212 spreads in the width direction of the light guide 212 and is emitted at a wide emission angle. The emission angle of the light emitted from the upper surface 212b of the light guide 212 is widened, for example, as shown by the solid line in FIG.
　このように、散乱液晶セル２１３を用いることにより、調光装置２１０から出射する光を、指向性を有する光と散乱光とに切り替えることができるので、光源部２１１は、導光体２１２の一端面２１２ａ側にのみ設置すればよく、また、導光体２１２も従来のように積層することなく、１層のみ用いればよい。
　また、光源部２１１を、導光体２１２の一端面２１２ａ側にのみ設置することによって、散乱液晶セル２１３を透過する光の指向性の切り替えの前後において、光源部２１１からの光の進行方向は変わらない。これにより、導光体２１２において、出射光を均一にするための設計（導波光立ち上げ用の構造の間引きなど）が、入射光が指向性を有する光または散乱光のいずれであっても、有効に機能する。したがって、散乱液晶セル２１３を透過する光の指向性の切り替えの前後において、照明装置１０からの出射光の輝度の均一性をある程度保つことができる。 As described above, by using the scattering liquid crystal cell 213, the light emitted from the light control device 210 can be switched between directional light and scattered light. It suffices to install it only on the end face 212a side, and the light guide 212 may be used only in one layer without being laminated as in the prior art.
Further, by installing the light source unit 211 only on the one end surface 212a side of the light guide 212, the traveling direction of the light from the light source unit 211 before and after switching the directivity of the light transmitted through the scattering liquid crystal cell 213 is does not change. Thereby, in the light guide 212, whether the design for making the emitted light uniform (such as thinning of the structure for raising the guided light) is either directional light or scattered light, Works effectively. Therefore, before and after switching the directivity of the light transmitted through the scattering liquid crystal cell 213, the uniformity of the luminance of the emitted light from the illumination device 10 can be maintained to some extent.
　光源部２１１を構成する光源としては、ＬＥＤ、無機ＥＬ、有機ＥＬなどが挙げられる。 Examples of the light source constituting the light source unit 211 include an LED, an inorganic EL, and an organic EL.
　導光体２１２は、シート状をなしており、ガラス、石英などからなる無機材料基板、ポリエチレンテレフタレート、ポリカーボネート、ポリイミド、ポリメタクリル酸メチル（ポリメチルメタクリレート、ＰＭＭＡ）などからなるプラスチック基板などから構成されている。 The light guide 212 has a sheet shape and is composed of an inorganic material substrate made of glass, quartz or the like, a plastic substrate made of polyethylene terephthalate, polycarbonate, polyimide, polymethyl methacrylate (polymethyl methacrylate, PMMA), or the like. ing.
　散乱液晶セル２１３を構成する透明導電基板２２２，２２３の透明基板２２４，２２６は、シート状をなしており、ガラス、石英などからなる無機材料基板、ポリエチレンテレフタレート、ポリカーボネート、ポリイミド、ポリメタクリル酸メチル（ポリメチルメタクリレート、ＰＭＭＡ）などからなるプラスチック基板などから構成されている。
　散乱液晶セル２１３を構成する透明導電基板２２２，２３の透明導電膜２２５，２２７は、インジウム錫酸化物（Ｉｎｄｉｕｍ　Ｔｉｎ　Ｏｘｉｄｅ、ＩＴＯ）などから構成されている。 The transparent substrates 224 and 226 of the transparent conductive substrates 222 and 223 constituting the scattering liquid crystal cell 213 are in the form of a sheet, and are made of an inorganic material substrate made of glass, quartz, etc., polyethylene terephthalate, polycarbonate, polyimide, polymethyl methacrylate ( A plastic substrate made of polymethylmethacrylate, PMMA) or the like.
The transparent conductive films 225 and 227 of the transparent conductive substrates 222 and 23 constituting the scattering liquid crystal cell 213 are made of indium tin oxide (ITO) or the like.
　反射ミラー２１４としては、レンズ２１５の外面に形成されたアルミニウムの蒸着膜、レンズ２１５の外面に貼着された誘電体ミラーなどが挙げられる。そして、反射ミラー２１４では、レンズ２１５と接する面が反射面２１４ａとなっている。
　反射ミラー２１４が誘電体ミラーからなる場合、１つの誘電体ミラーが単純に設置される場合と、２つ以上の誘電体ミラーが光学接着されて設置される場合とがある。 Examples of the reflecting mirror 214 include an aluminum vapor deposition film formed on the outer surface of the lens 215, and a dielectric mirror attached to the outer surface of the lens 215. In the reflection mirror 214, the surface in contact with the lens 215 is a reflection surface 214a.
When the reflecting mirror 214 is made of a dielectric mirror, there are a case where one dielectric mirror is simply installed and a case where two or more dielectric mirrors are optically bonded.
　レンズ２１５は、ガラス、石英などからなる無機材料、ポリメタクリル酸メチル（ポリメチルメタクリレート、ＰＭＭＡ）などからなるプラスチックなどの光透過性の材料から構成されている。また、レンズ２１５は、外側の骨格部分が前記の材料からなり、内部が中空構造をなしていてもよく、あるいは、全体が前記の材料からなる中実構造をなしていてもよい。 The lens 215 is made of a light transmissive material such as an inorganic material made of glass, quartz, or the like, or a plastic made of polymethyl methacrylate (polymethyl methacrylate, PMMA) or the like. Further, the lens 215 may have an outer skeleton portion made of the above-described material and may have a hollow structure inside, or may have a solid structure made entirely of the above-described material.
　［第１０実施形態］
　図３８Ａは、調光装置の第１０実施形態を示す概略図である。図３８Ａは側面図である。図３８Ｂは、図３８Ａの一部を拡大した斜視図である。
　調光装置２５０は、光源部２５１と、導光体２５２と、液晶レンズ２５３とから概略構成されている。導光体２５２は、光源部２５１に対向して配置される。導光体２５２は、光源部２５１からの光がその一端面２５２ａ側から導入されるとともに、光源部２５１からの光をその長手方向に導光する。液晶レンズ２５３は、光源部２５１と導光体２５２の一端面２５２ａとの間に設けられる。
　本実施形態では、光源部２５１からの光に指向性を変化させる配光変換素子として、液晶レンズ２５３を用いている。 [Tenth embodiment]
FIG. 38A is a schematic diagram illustrating a tenth embodiment of the light control device. FIG. 38A is a side view. FIG. 38B is an enlarged perspective view of a part of FIG. 38A.
The light control device 250 is generally configured by a light source unit 251, a light guide 252, and a liquid crystal lens 253. The light guide 252 is disposed to face the light source unit 251. The light guide 252 guides the light from the light source 251 in the longitudinal direction while the light from the light source 251 is introduced from the one end face 252a side. The liquid crystal lens 253 is provided between the light source unit 251 and the one end surface 252a of the light guide 252.
In the present embodiment, a liquid crystal lens 253 is used as a light distribution conversion element that changes the directivity of light from the light source unit 251.
　液晶レンズ２５３としては、特に限定されるものではなく、電圧を印加することにより屈折率が変化するものであれば、公知の液晶レンズを適用することができる。液晶レンズ２５３としては、例えば、第一透明基板２５４と、第二透明基板２５５と、第一透明電極２５６と、第二透明電極２５７と、絶縁性スペーサ２５８と、液晶層２５９とから構成される単位が複数連設されたものが用いられる。 The liquid crystal lens 253 is not particularly limited, and a known liquid crystal lens can be used as long as the refractive index is changed by applying a voltage. The liquid crystal lens 253 includes, for example, a first transparent substrate 254, a second transparent substrate 255, a first transparent electrode 256, a second transparent electrode 257, an insulating spacer 258, and a liquid crystal layer 259. A unit in which a plurality of units are connected is used.
　光源部２５１、導光体２５２としては、上述の第９実施形態と同様のものが用いられる。 The light source unit 251 and the light guide 252 are the same as those in the ninth embodiment.
　図３９Ａは、液晶レンズ２５３に電圧を印加せずに、調光装置２５０を用いた場合を説明する概略側面図である。
　このとき、液晶レンズ２５３を構成する液晶が、液晶レンズ２５３の厚さ方向に配向しているので、光源部２５１からの光が液晶レンズ２５３に入射すると、その入射光は液晶レンズ２５３内の液晶によって散乱されることなく、指向性を有する光として、一端面２５２ａから導光体２５２に入射する。したがって、導光体２５２の上面２５２ｂから出射する光は、導光体２５２の幅方向に拡がることなく、狭い出射角で出射する。 FIG. 39A is a schematic side view illustrating the case where the light control device 250 is used without applying a voltage to the liquid crystal lens 253. FIG.
At this time, since the liquid crystal constituting the liquid crystal lens 253 is aligned in the thickness direction of the liquid crystal lens 253, when light from the light source unit 251 enters the liquid crystal lens 253, the incident light is liquid crystal in the liquid crystal lens 253. The light having directivity enters the light guide 252 from the one end face 252a without being scattered by the light. Therefore, the light emitted from the upper surface 252b of the light guide 252 is emitted at a narrow emission angle without spreading in the width direction of the light guide 252.
　図３９Ｂは、液晶レンズ２５３に電圧を印加して、調光装置２５０を用いた場合を説明する概略側面図である。
　このとき、液晶レンズ２５３を構成する液晶が、液晶レンズ２５３の厚さ方向に配向することなく、散乱するので、光源部２５１からの光が液晶レンズ２５３に入射すると、その入射光は液晶レンズ２５３内の液晶によって散乱され、散乱光となって、一端面２５２ａから導光体２５２に入射する。したがって、導光体２５２の上面２５２ｂから出射する光は、導光体２５２の幅方向に拡がり、広い出射角で出射する。 FIG. 39B is a schematic side view for explaining a case where a voltage is applied to the liquid crystal lens 253 and the light control device 250 is used.
At this time, since the liquid crystal constituting the liquid crystal lens 253 is scattered without being oriented in the thickness direction of the liquid crystal lens 253, when the light from the light source unit 251 enters the liquid crystal lens 253, the incident light is the liquid crystal lens 253. It is scattered by the liquid crystal inside and becomes scattered light, and enters the light guide 252 from the one end face 252a. Therefore, the light emitted from the upper surface 252b of the light guide 252 spreads in the width direction of the light guide 252 and is emitted with a wide emission angle.
　［第１１実施形態］
　図４０Ａおよび図４０Ｂは、調光装置の第１１実施形態を示す概略図である。図４０Ａは、平面図である。図４０Ｂは、図４０ＡのＢ２－Ｂ２線に沿う断面図である。
　調光装置２６０は、光源部２６１と、導光体２６２と、散乱体２６３と、反射ミラー２６４を備えたパラボラミラー形状のレンズ２６５とから概略構成されている。導光体２６２は、光源部２６１に対向して配置される。導光体２６２は、光源部２６１からの光がその一端面２６２ａ側から導入されるとともに、光源部２６１からの光をその長手方向に導光する。散乱体２６３は、光源部２６１と導光体２６２の一端面２６２ａとの間に、挿抜可能に設けられる。パラボラミラー形状のレンズ２６５は、光源部２６１の導光体２６２の一端面２６２ａと対向する面２６１ａとは反対の面側に設けられる。反射ミラー２６４は、光源部２６１からの光を反射する反射面２６４ａを有する。
　本実施形態では、光源部２６１からの光に指向性を変化させる配光変換素子として、散乱体２６３を用いている。 [Eleventh embodiment]
40A and 40B are schematic views illustrating an eleventh embodiment of the light control device. FIG. 40A is a plan view. 40B is a cross-sectional view taken along line B2-B2 of FIG. 40A.
The light control device 260 is schematically configured by a light source unit 261, a light guide 262, a scatterer 263, and a parabolic mirror-shaped lens 265 including a reflection mirror 264. The light guide 262 is disposed to face the light source unit 261. The light guide 262 guides the light from the light source 261 in the longitudinal direction while the light from the light source 261 is introduced from the one end face 262a side. The scatterer 263 is provided between the light source unit 261 and the one end surface 262a of the light guide 262 so as to be insertable / removable. The parabolic mirror-shaped lens 265 is provided on the surface opposite to the surface 261 a facing the one end surface 262 a of the light guide 262 of the light source unit 261. The reflection mirror 264 has a reflection surface 264 a that reflects light from the light source unit 261.
In the present embodiment, a scatterer 263 is used as a light distribution conversion element that changes directivity to light from the light source unit 261.
　散乱体２６３の材料としては、光透過性の樹脂中に光散乱性粒子を分散したものを用いることが好ましい。
　光散乱性粒子として、無機材料により構成された粒子（無機微粒子）を用いる場合には、例えば、シリカビーズ（屈折率：１．４４）、アルミナビーズ（屈折率：１．６３）、酸化チタンビーズ（屈折率　アナタース型：２．５０、ルチル型：２．７０）、酸化ジルコニアビーズ（屈折率：２．０５）、酸化亜鉛ビーズ（屈折率：２．００）、チタン酸バリウム（ＢａＴｉＯ３）（屈折率：２.４）などが挙げられる。 As a material of the scatterer 263, it is preferable to use a material in which light-scattering particles are dispersed in a light-transmitting resin.
When particles (inorganic fine particles) made of an inorganic material are used as the light scattering particles, for example, silica beads (refractive index: 1.44), alumina beads (refractive index: 1.63), titanium oxide beads (Refractive index anatase type: 2.50, rutile type: 2.70), zirconia bead (refractive index: 2.05), zinc oxide bead (refractive index: 2.00), barium titanate (BaTiO 3 ) ( Refractive index: 2.4) etc. are mentioned.
　光散乱性粒子として、有機材料により構成された粒子（有機微粒子）を用いる場合には、例えば、ポリメチルメタクリレートビーズ（屈折率：１．４９）、アクリルビーズ（屈折率：１．５０）、アクリル－スチレン共重合体ビーズ（屈折率：１．５４）、メラミンビーズ（屈折率：１．５７）、高屈折率メラミンビーズ（屈折率：１．６５）、ポリカーボネートビーズ（屈折率：１．５７）、スチレンビーズ（屈折率：１．６０）、架橋ポリスチレンビーズ（屈折率：１．６１）、ポリ塩化ビニルビーズ（屈折率：１．６０）、ベンゾグアナミン－メラミンホルムアルデヒドビーズ（屈折率：１．６８）、シリコーンビーズ（屈折率：１．５０）などが挙げられる。 When particles (organic fine particles) made of an organic material are used as the light scattering particles, for example, polymethyl methacrylate beads (refractive index: 1.49), acrylic beads (refractive index: 1.50), acrylic -Styrene copolymer beads (refractive index: 1.54), melamine beads (refractive index: 1.57), high refractive index melamine beads (refractive index: 1.65), polycarbonate beads (refractive index: 1.57) Styrene beads (refractive index: 1.60), crosslinked polystyrene beads (refractive index: 1.61), polyvinyl chloride beads (refractive index: 1.60), benzoguanamine-melamine formaldehyde beads (refractive index: 1.68) And silicone beads (refractive index: 1.50).
　光散乱性粒子と混合して用いる樹脂材料としては、例えば、アクリル樹脂（屈折率：１．４９）、メラミン樹脂（屈折率：１．５７）、ナイロン（屈折率：１．５３）、ポリスチレン（屈折率：１．６０）、メラミンビーズ（屈折率：１．５７）、ポリカーボネート（屈折率：１．５７）、ポリ塩化ビニル（屈折率：１．６０）、ポリ塩化ビニリデン（屈折率：１．６１）、ポリ酢酸ビニル（屈折率：１．４６）、ポリエチレン（屈折率：１．５３）、ポリメタクリル酸メチル（屈折率：１．４９）、ポリＭＢＳ（屈折率：１．５４）、中密度ポリエチレン（屈折率：１．５３）、高密度ポリエチレン（屈折率：１．５４）、テトラフルオロエチレン（屈折率：１．３５）、ポリ三フッ化塩化エチレン（屈折率：１．４２）、ポリテトラフルオロエチレン（屈折率：１．３５）などが挙げられる。 Examples of the resin material used by mixing with light scattering particles include acrylic resin (refractive index: 1.49), melamine resin (refractive index: 1.57), nylon (refractive index: 1.53), polystyrene ( Refractive index: 1.60), melamine beads (refractive index: 1.57), polycarbonate (refractive index: 1.57), polyvinyl chloride (refractive index: 1.60), polyvinylidene chloride (refractive index: 1. 61), polyvinyl acetate (refractive index: 1.46), polyethylene (refractive index: 1.53), polymethyl methacrylate (refractive index: 1.49), poly MBS (refractive index: 1.54), medium Density polyethylene (refractive index: 1.53), high density polyethylene (refractive index: 1.54), tetrafluoroethylene (refractive index: 1.35), poly (ethylene trifluoride) chloride (refractive index: 1.42), Polytetrafu Oroechiren (refractive index: 1.35), and the like.
　散乱体２６３は、手動または微小電子機械システム（ＭＥＭＳ）制御（アクチュエーター）などによって、光源部２６１と導光体２６２の一端面２６２ａとの間に、挿抜可能となっている。 The scatterer 263 can be inserted / removed between the light source 261 and the one end surface 262a of the light guide 262 by manual or micro electro mechanical system (MEMS) control (actuator).
　光源部２６１、導光体２６２、反射ミラー２６４、レンズ２６５としては、上述の第９実施形態と同様のものが用いられる。 The light source unit 261, the light guide 262, the reflection mirror 264, and the lens 265 are the same as those in the ninth embodiment described above.
　図４１Ａ～図４１Ｃは、光源部と導光体の一端面との間に、散乱体を挿入していない状態を示す概略図である。図４１Ａは、平面図である。図４１Ｂは、導光体の一端面側から見た正面図である。図４１Ｃは、図４１ＡのＣ２－Ｃ２線に沿う断面図である。
　このとき、光源部２６１からの光が、反射ミラー２６４の反射面２６４ａで反射して、その反射光が、導光体２６２側に向かうが、散乱体２６３を透過しないので、指向性を有する光として、一端面２６２ａから導光体２６２に入射する。したがって、導光体２６２の上面２６２ｂから出射する光は、導光体２６２の幅方向に拡がることなく、狭い出射角で出射する。 41A to 41C are schematic views showing a state in which no scatterer is inserted between the light source section and one end face of the light guide. FIG. 41A is a plan view. FIG. 41B is a front view seen from one end surface side of the light guide. 41C is a cross-sectional view taken along line C2-C2 of FIG. 41A.
At this time, the light from the light source unit 261 is reflected by the reflection surface 264a of the reflection mirror 264, and the reflected light travels toward the light guide 262, but does not pass through the scatterer 263. The light enters the light guide 262 from the one end surface 262a. Therefore, the light emitted from the upper surface 262b of the light guide 262 is emitted at a narrow emission angle without spreading in the width direction of the light guide 262.
　図４２Ａ～図４２Ｃは、光源部と導光体の一端面との間に、散乱体を挿入した状態を示す概略図である。図４２Ａは、平面図である。図４２Ｂは、導光体の一端面側から見た正面図である。図４２Ｃは、図４２ＡのＤ２－Ｄ２線に沿う断面図である。
　このとき、光源部２６１からの光が、反射ミラー２６４の反射面２６４ａで反射して、その反射光が、散乱体２６３に入射すると、反射光は散乱体２６３内の光散乱性粒子によって散乱され、散乱光となって、一端面２６２ａから導光体２６２に入射する。したがって、導光体２６２の上面２６２ｂから出射する光は、導光体２６２の幅方向に拡がり、広い出射角で出射する。 42A to 42C are schematic views showing a state in which a scatterer is inserted between the light source section and one end face of the light guide. FIG. 42A is a plan view. FIG. 42B is a front view seen from one end surface side of the light guide. FIG. 42C is a sectional view taken along line D2-D2 of FIG. 42A.
At this time, when the light from the light source unit 261 is reflected by the reflection surface 264a of the reflection mirror 264 and the reflected light enters the scatterer 263, the reflected light is scattered by the light scattering particles in the scatterer 263. The light becomes scattered light and enters the light guide 262 from the one end surface 262a. Therefore, the light emitted from the upper surface 262b of the light guide 262 spreads in the width direction of the light guide 262 and is emitted with a wide emission angle.
　このように、散乱体２６３を、光源部２６１と導光体２６２の一端面２６２ａとの間に挿抜可能に設けることにより、調光装置２６０から出射する光を、指向性を有する光と散乱光とに切り替えることができる。 In this manner, by providing the scatterer 263 so as to be insertable / removable between the light source unit 261 and the one end surface 262a of the light guide 262, light emitted from the light control device 260 is converted into light having directivity and scattered light. And can be switched.
　［第１２実施形態］
　図４３は、調光装置の第１２実施形態を示す概略断面図である。
　調光装置２７０は、光源部２７１と、導光体２７２と、反射ミラー２７３を備えたパラボラミラー形状のレンズ２７４と、ゲル２７５と、散乱パターン２７６と、一対の反射板２７７，２７８とから概略構成されている。導光体２７２は、光源部２７１に対向して配置される。導光体２７２は、光源部２７１からの光がその一端面２７２ａ側から導入されるとともに、光源部２７１からの光をその長手方向に導光する。パラボラミラー形状のレンズ２７４は、光源部２７１の導光体２７２の一端面２７２ａと対向する面２７１ａとは反対の面側に設けられる。反射ミラー２７３は、光源部２７１からの光を反射する反射面２７３ａを有する。ゲル２７５は、光源部２７１およびレンズ２７４と導光体２７２の一端面２７２ａとの間に設けられる。ゲル２７５は、光源部２７１およびレンズ２７４と導光体２７２の一端面２７２ａとを光学接着が可能である。散乱パターン２７６は、導光体２７２の一端面２７２ａに設けられる。一対の反射板２７７，２７８は、ゲル２７５と導光体２７２の一端面２７２ａとの境界部を、導光体２７２の厚さ方向から挟持する一対の反射板２７７，２７８とから概略構成されている。
　本実施形態では、反射ミラー２７３とレンズ２７４が入光部を構成している。また、本実施形態では、光源部２７１からの光に指向性を変化させる配光変換素子として、ゲル２７５を用いている。 [Twelfth embodiment]
FIG. 43 is a schematic cross-sectional view showing a twelfth embodiment of the light control device.
The light control device 270 is roughly composed of a light source 271, a light guide 272, a parabolic mirror-shaped lens 274 provided with a reflection mirror 273, a gel 275, a scattering pattern 276, and a pair of reflection plates 277 and 278. It is configured. The light guide 272 is disposed to face the light source unit 271. The light guide 272 guides the light from the light source 271 in the longitudinal direction while the light from the light source 271 is introduced from the one end face 272a side. The parabolic mirror-shaped lens 274 is provided on the side opposite to the surface 271 a facing the one end surface 272 a of the light guide 272 of the light source unit 271. The reflection mirror 273 has a reflection surface 273 a that reflects light from the light source unit 271. The gel 275 is provided between the light source unit 271 and the lens 274 and the one end surface 272a of the light guide 272. The gel 275 can optically bond the light source portion 271 and the lens 274 to the one end surface 272a of the light guide 272. The scattering pattern 276 is provided on the one end surface 272 a of the light guide 272. The pair of reflectors 277 and 278 is generally configured by a pair of reflectors 277 and 278 that sandwich the boundary between the gel 275 and the one end surface 272a of the light guide 272 from the thickness direction of the light guide 272. Yes.
In the present embodiment, the reflection mirror 273 and the lens 274 constitute a light incident part. In this embodiment, the gel 275 is used as a light distribution conversion element that changes the directivity to the light from the light source unit 271.
　ゲル２７５としては、特に限定されるものではないが、光透過性であり、光源部２７１およびレンズ２７４と導光体２７２の一端面２７２ａとを光学接着が可能なものであれば、いかなるものでも用いられる。
　また、ゲル２７５と導光体２７２の一端面２７２ａとの境界部は、手動または微小電子機械システム（ＭＥＭＳ）制御（アクチュエーター）などによって、導光体２７２の長手方向に沿って可動するようになっている。これにより、ゲル２７５と導光体２７２の一端面２７２ａとは、所定の間隔を置いて離隔した状態と、互いに接触した状態とをなすようになっている。 The gel 275 is not particularly limited, but any gel can be used as long as it is light transmissive and can optically bond the light source 271 and the lens 274 to the one end surface 272a of the light guide 272. Used.
Further, the boundary portion between the gel 275 and the one end surface 272a of the light guide 272 is movable along the longitudinal direction of the light guide 272 by manual or micro electro mechanical system (MEMS) control (actuator). ing. Thereby, the gel 275 and the one end surface 272a of the light guide 272 are separated from each other by a predetermined distance and in contact with each other.
　散乱パターン２７６は、導光体２７２の一端面２７２ａに形成された凹凸パターンなどである。 The scattering pattern 276 is an uneven pattern formed on the one end surface 272a of the light guide 272.
　反射板２７７，２７８としては、特に限定されるものではないが、ゲル２７５および導光板２７２よりも屈折率の低い材料、あるいは、金属などから構成されるものが用いられる。 The reflecting plates 277 and 278 are not particularly limited, but materials made of a material having a refractive index lower than that of the gel 275 and the light guide plate 272 or a metal are used.
　光源部２７１、導光体２７２、反射ミラー２７３、レンズ２７４としては、上述の第９実施形態と同様のものが用いられる。 As the light source 271, the light guide 272, the reflection mirror 273, and the lens 274, the same ones as those in the ninth embodiment described above are used.
　図４４Ａは、ゲルと導光体の一端面とが所定の間隔を置いて離隔して調光装置を用いた状態を示す概略断面図である。
　このとき、光源部２７１からの光が、反射ミラー２７３の反射面２７３ａで反射して、その反射光が、ゲル２７５を透過し、さらに、散乱体パターン２７６を透過すると、反射光は散乱体パターン２７６によって散乱され、散乱光となって、一端面２７２ａから導光体２７２に入射する。したがって、導光体２７２の上面２７２ｂから出射する光は、導光体２７２の幅方向に拡がり、広い出射角で出射する。 FIG. 44A is a schematic cross-sectional view showing a state in which the light control device is used with the gel and one end face of the light guide spaced apart from each other with a predetermined interval.
At this time, when the light from the light source unit 271 is reflected by the reflection surface 273a of the reflection mirror 273, and the reflected light passes through the gel 275 and further passes through the scatterer pattern 276, the reflected light becomes the scatterer pattern. The light is scattered by 276 to become scattered light and enters the light guide 272 from the one end surface 272a. Therefore, the light emitted from the upper surface 272b of the light guide 272 spreads in the width direction of the light guide 272 and is emitted with a wide emission angle.
　図４４Ｂは、ゲルと導光体の一端面とが互いに接触した状態で調光装置を用いた状態を示す概略断面図である。
　このとき、光源部２７１からの光が、反射ミラー２７３の反射面２７３ａで反射して、その反射光が、ゲル２７５を透過し、さらに、散乱体パターン２７６を透過しても、反射光は散乱体パターン２７６によって散乱されず、指向性を有する光として、一端面２７２ａから導光体２７２に入射する。したがって、導光体２７２の上面２７２ｂから出射する光は、導光体２７２の幅方向に拡がることなく、狭い出射角で出射する。 FIG. 44B is a schematic cross-sectional view showing a state where the light control device is used in a state where the gel and one end surface of the light guide are in contact with each other.
At this time, even if the light from the light source unit 271 is reflected by the reflection surface 273a of the reflection mirror 273 and the reflected light passes through the gel 275 and further passes through the scatterer pattern 276, the reflected light is scattered. The light having directivity is not scattered by the body pattern 276 and enters the light guide 272 from the one end surface 272a. Therefore, the light emitted from the upper surface 272b of the light guide 272 is emitted at a narrow emission angle without spreading in the width direction of the light guide 272.
このように、光源部２７１およびレンズ２７４と導光体２７２の一端面２７２ａとを光学接着が可能なゲル２７５を設けることにより、調光装置２７０から出射する光を、指向性を有する光と散乱光とに切り替えることができる。 In this way, by providing the gel 275 capable of optically bonding the light source unit 271 and the lens 274 and the one end surface 272a of the light guide 272, light emitted from the light control device 270 is scattered with light having directivity. You can switch to light.
なお、本実施形態では、反射ミラー２７３とレンズ２７４が入光部を構成する場合を例示したが、本実施形態はこれに限定されない。本実施形態にあっては、入光部が楔形状の導光体、凸レンズなどであってもよい。 In the present embodiment, the case where the reflection mirror 273 and the lens 274 configure the light incident part is illustrated, but the present embodiment is not limited to this. In the present embodiment, the light incident portion may be a wedge-shaped light guide, a convex lens, or the like.
　［第１３実施形態］
　図４５Ａおよび図４５Ｂは、調光装置の第１３実施形態を示す概略図である。図４５Ａは、平面図である。図４５Ｂは、側面図である。
　調光装置２８０は、光源部２８１と、楔形状の導光体２８２と、プリズム２８３と、導光体２８４と、散乱液晶セル２８５とから概略構成されている。導光体２８２は、光源部２８１に対向して配置される。導光体２８２は、光源部２８１からの光がその一端面２８２ａ側から導入される。プリズム２８３は、導光体２８２の側面（斜面２８２ｂと対向する面）２８２ｃに対向する。プリズム２８３は、光の入射面（導光体２８２の側面２８２ｃと対向する面）２８３ａが鋸刃形状をなす。導光体２８４は、導光体２８２およびプリズム２８３によって導かれた、光源部２８１からの光をその長手方向に導光する。散乱液晶セル２８５は、プリズム２８３と導光体２８４の一端面２８４ａとの間に設けられる。
　本実施形態では、光源部２８１からの光に指向性を変化させる配光変換素子として、導光体２８２とプリズム２８３を用いている。 [Thirteenth embodiment]
45A and 45B are schematic views showing a thirteenth embodiment of the light control device. FIG. 45A is a plan view. FIG. 45B is a side view.
The light control device 280 is generally configured by a light source unit 281, a wedge-shaped light guide 282, a prism 283, a light guide 284, and a scattering liquid crystal cell 285. The light guide 282 is disposed to face the light source unit 281. Light from the light source unit 281 is introduced into the light guide 282 from the one end surface 282a side. The prism 283 faces the side surface (the surface facing the inclined surface 282b) 282c of the light guide 282. In the prism 283, a light incident surface (a surface facing the side surface 282c of the light guide 282) 283a has a saw blade shape. The light guide 284 guides the light from the light source unit 281 guided by the light guide 282 and the prism 283 in the longitudinal direction thereof. The scattering liquid crystal cell 285 is provided between the prism 283 and the one end surface 284 a of the light guide 284.
In the present embodiment, a light guide 282 and a prism 283 are used as light distribution conversion elements that change the directivity of light from the light source unit 281.
　導光体２８２は、ガラス、石英などからなる無機材料、ポリメタクリル酸メチル（ポリメチルメタクリレート、ＰＭＭＡ）などからなるプラスチックなどの光透過性の材料から構成されている。 The light guide 282 is made of an optically transparent material such as an inorganic material made of glass, quartz, or the like, or a plastic made of polymethyl methacrylate (polymethyl methacrylate, PMMA) or the like.
　プリズム２８３は、ガラス、石英などからなる無機材料、ポリメタクリル酸メチル（ポリメチルメタクリレート、ＰＭＭＡ）などからなるプラスチックなどの光透過性の材料から構成されている。 The prism 283 is made of a light-transmitting material such as an inorganic material made of glass, quartz or the like, or a plastic made of polymethyl methacrylate (polymethyl methacrylate, PMMA) or the like.
　光源部２８１、導光体２８４としては、上述の第９実施形態と同様のものが用いられる。 As the light source unit 281 and the light guide 284, those similar to those in the ninth embodiment are used.
　図４６に示すように、調光装置２８０では、光源部２８１から導光体２８２に入射された光が、導光体２８２の斜面２８２ｂと側面２８２ｃで反射を繰り返して、導光体２８２内を伝搬するが、その光の一部が側面２８２ｃを透過する。導光体２８２の側面２８２ｃを透過した光が、側面２８２ｃを出射する角度αが、プリズム２８３の入射面２８３ａにおいて全反射する角度未満である場合、その光はプリズム２８３の入射面２８３ａによって散乱されず、指向性を有する光として、一端面２８４ａから導光体２８４に入射する。したがって、導光体２８４の上面２８４ｂから出射する光は、導光体２８４の幅方向に拡がることなく、狭い出射角で出射する。 As shown in FIG. 46, in the light control device 280, the light incident on the light guide 282 from the light source unit 281 is repeatedly reflected by the inclined surface 282b and the side surface 282c of the light guide 282, and the light guide 282 is passed through. Although propagating, a part of the light is transmitted through the side surface 282c. When the angle α at which the light transmitted through the side surface 282c of the light guide 282 exits the side surface 282c is less than the angle at which the light is totally reflected at the incident surface 283a of the prism 283, the light is scattered by the incident surface 283a of the prism 283. Instead, the light having directivity enters the light guide 284 from the one end face 284a. Therefore, the light emitted from the upper surface 284 b of the light guide 284 is emitted at a narrow emission angle without spreading in the width direction of the light guide 284.
　このように、光源部２８１からの光がその一端面２８２ａ側から導入される楔形状の導光体２８２と、導光体２８２の側面２８２ｃに対向し、光の入射面２８３ａが鋸刃形状をなすプリズム２８３とを設けることにより、調光装置２８０から出射する光を、指向性を有する光とすることができる。 In this way, the light from the light source unit 281 is opposed to the wedge-shaped light guide 282 to which the light is introduced from the one end face 282a side, and the side 282c of the light guide 282, and the light incident surface 283a has a saw blade shape. By providing the prism 283 formed, the light emitted from the light control device 280 can be changed to light having directivity.
　なお、本実施形態では、光源部２８１と導光体２８２がそれぞれ１つずつ設けられた場合を例示したが、本実施形態はこれに限定されない。本実施形態にあっては、図４７に示すように、光源部２８１と導光体２８２からなる単位を複数設けてもよい。 In addition, in this embodiment, although the case where the light source part 281 and the light guide 282 were each provided 1 each was illustrated, this embodiment is not limited to this. In the present embodiment, as shown in FIG. 47, a plurality of units each including a light source unit 281 and a light guide 282 may be provided.
　［第１４実施形態］
　図４８は、調光装置の第１４実施形態を示す概略平面図であり、調光装置を構成するパラボラミラー形状のレンズを示す図である。
　本実施形態のパラボラミラー形状のレンズ２９１は、光源部２１０１の導光体（図示略）の一端面と対向する面２１０１ａとは反対の面側に設けられている。レンズ２９１は、光源部２１０１からの光を反射する反射面２９２ａを有する反射ミラー２９２と、反射ミラー２９２の反射面２９２ａに沿って設けられた３散乱液晶セル２９３とを備えている。
　本実施形態では、光源部２１０１からの光に指向性を変化させる配光変換素子として、散乱液晶セル２９３を備えたレンズ２９１を用いている。 [Fourteenth embodiment]
FIG. 48 is a schematic plan view showing a fourteenth embodiment of the light control device, and shows a parabolic mirror-shaped lens constituting the light control device.
The parabolic mirror-shaped lens 291 of the present embodiment is provided on the side opposite to the surface 2101 a facing the one end surface of the light guide (not shown) of the light source unit 2101. The lens 291 includes a reflection mirror 292 having a reflection surface 292 a that reflects light from the light source unit 2101, and a three-scattering liquid crystal cell 293 provided along the reflection surface 292 a of the reflection mirror 292.
In the present embodiment, a lens 291 including a scattering liquid crystal cell 293 is used as a light distribution conversion element that changes the directivity of light from the light source unit 2101.
　本実施形態では、散乱液晶セル２９３の厚さと、レンズ２９１と散乱液晶セル２９３の屈折率差とによって、調光装置からの出射光の指向性が変化する。
　したがって、調光装置からの出射光の指向性に与える影響を小さくするためには、散乱液晶セル２９３の厚さが薄いことが好ましく、レンズ２９１と散乱液晶セル２９３の屈折率差が小さいことが好ましい。
　光源部２１０１、レンズ２９１としては、上述の第９実施形態と同様のものが用いられる。 In the present embodiment, the directivity of light emitted from the light control device varies depending on the thickness of the scattering liquid crystal cell 293 and the refractive index difference between the lens 291 and the scattering liquid crystal cell 293.
Therefore, in order to reduce the influence on the directivity of the emitted light from the light control device, it is preferable that the thickness of the scattering liquid crystal cell 293 is thin, and the difference in refractive index between the lens 291 and the scattering liquid crystal cell 293 is small. preferable.
The light source unit 2101 and the lens 291 are the same as those in the ninth embodiment.
　ここで、図４９Ａおよび図４９Ｂを参照して、例えば、散乱液晶セル２９３を構成する高分子分散液晶としてリバースモード高分子分散液晶を用いた場合について説明する。
　図４９Ａに示すように、散乱液晶セル２９３に電圧を印加していない場合、液晶が散乱液晶セル２９３の厚さ方向と垂直な方向に配向するので、散乱液晶セル２９３は透明になる。したがって、光源部２１０１からの光が、反射ミラー２９２の反射面２９２ａで反射して、その反射光が、散乱液晶セル２９３を透過しても、反射光は液晶によって散乱されずることなく、散乱液晶セル２９３から指向性を有する光として出射する。
　一方、図４９Ｂに示すように、散乱液晶セル２９３に電圧を印加した場合、液晶が散乱液晶セル２９３の厚さ方向に配向する。したがって、光源部２１０１からの光が、反射ミラー２９２の反射面２９２ａで反射して、その反射光が、散乱液晶セル２９３に入射すると、その光が液晶によって散乱されて、散乱液晶セル２９３から散乱光となって出射する。 Here, with reference to FIG. 49A and FIG. 49B, for example, a case where a reverse mode polymer dispersed liquid crystal is used as the polymer dispersed liquid crystal constituting the scattering liquid crystal cell 293 will be described.
As shown in FIG. 49A, when no voltage is applied to the scattering liquid crystal cell 293, the liquid crystal is aligned in a direction perpendicular to the thickness direction of the scattering liquid crystal cell 293, so that the scattering liquid crystal cell 293 becomes transparent. Therefore, even if the light from the light source unit 2101 is reflected by the reflection surface 292a of the reflection mirror 292 and the reflected light passes through the scattering liquid crystal cell 293, the reflected light is not scattered by the liquid crystal, and the scattered liquid crystal. Light is emitted from the cell 293 as light having directivity.
On the other hand, as shown in FIG. 49B, when a voltage is applied to the scattering liquid crystal cell 293, the liquid crystal is aligned in the thickness direction of the scattering liquid crystal cell 293. Accordingly, when light from the light source unit 2101 is reflected by the reflection surface 292a of the reflection mirror 292 and the reflected light enters the scattering liquid crystal cell 293, the light is scattered by the liquid crystal and scattered from the scattering liquid crystal cell 293. Emits light.
　なお、本実施形態では、散乱液晶セル２９３を構成する高分子分散液晶としてノーマルモード高分子分散液晶を用いてもよい。ノーマルモード高分子分散液晶を用いた場合、散乱液晶セル２９３に対する電圧の印加の有無による出射光の指向性は、リバースモード高分子分散液晶を用いた場合とは逆になる。 In this embodiment, a normal mode polymer dispersed liquid crystal may be used as the polymer dispersed liquid crystal constituting the scattering liquid crystal cell 293. When normal mode polymer dispersed liquid crystal is used, the directivity of outgoing light depending on whether or not voltage is applied to the scattering liquid crystal cell 293 is opposite to that when reverse mode polymer dispersed liquid crystal is used.
　［第１５実施形態］
　図５０は、調光装置の第１５実施形態を示す概略平面図であり、調光装置を構成するパラボラミラー形状のレンズを示す図である。
　本実施形態のパラボラミラー形状のレンズ２１１１は、光源部２１２１からの光を反射する反射面２１１２ａを有する反射ミラー２１１２と、微小電子機械システム（ＭＥＭＳ）制御（アクチュエーター）により、光源部２１２１側に出し入れ可能な複数の突起２１１３とを備えている。
　複数の突起２１１３は、反射ミラー２１１２の反射面２１１２ａに沿って、所定の間隔を置いて設けられている。
　本実施形態では、光源部２１２１からの光に指向性を変化させる配光変換素子として、突起２１１３を備えたレンズ２１１１を用いている。 [Fifteenth embodiment]
FIG. 50 is a schematic plan view showing the fifteenth embodiment of the light control device, and shows a parabolic mirror-shaped lens that constitutes the light control device.
The parabolic mirror-shaped lens 2111 of this embodiment is moved in and out of the light source unit 2121 side by a reflection mirror 2112 having a reflection surface 2112a that reflects light from the light source unit 2121 and a micro electro mechanical system (MEMS) control (actuator). And a plurality of possible projections 2113.
The plurality of protrusions 2113 are provided at predetermined intervals along the reflection surface 2112 a of the reflection mirror 2112.
In the present embodiment, a lens 2111 provided with protrusions 2113 is used as a light distribution conversion element that changes the directivity of light from the light source unit 2121.
　図５１Ａは、光源部２１２１側に複数の突起２１１３を突出させずに調光装置を用いた状態を示す概略平面図である。
　このとき、光源部２１２１からの光が、反射ミラー２１１２の反射面２１１２ａで反射して、その反射光が、再びレンズ２１１１に入射するが、反射光はレンズ２１１１内で散乱されず、レンズ２１１１から指向性を有する光として出射する。 FIG. 51A is a schematic plan view showing a state in which the light control device is used without projecting the plurality of protrusions 2113 on the light source unit 2121 side.
At this time, the light from the light source unit 2121 is reflected by the reflecting surface 2112a of the reflecting mirror 2112 and the reflected light is incident on the lens 2111 again. However, the reflected light is not scattered in the lens 2111 and is reflected from the lens 2111. It emits as directional light.
　図５１Ｂは、光源部２１２１側に複数の突起２１１３を突出させて調光装置を用いた状態を示す概略平面図である。
　このとき、光源部２１２１からの光が、反射ミラー２１１２の反射面２１１２ａで反射して、その反射光が、再びレンズ２１１１に入射し、反射光は、複数の突起２１１３によって散乱されて、レンズ２１１１から散乱光となって出射する。
　なお、本実施形態では、突起２１１３を反射ミラー２１１２の反射面２１１２ａよりも内側に収納して（引っ込めて）、反射ミラー２１１２の反射面２１１２ａに溝や穴を形成して、その溝や穴によって反射光を散乱させてもよい。 FIG. 51B is a schematic plan view illustrating a state in which a plurality of protrusions 2113 are protruded toward the light source unit 2121 and the light control device is used.
At this time, the light from the light source unit 2121 is reflected by the reflection surface 2112a of the reflection mirror 2112, and the reflected light is incident on the lens 2111 again. The reflected light is scattered by the plurality of protrusions 2113, and the lens 2111 To be emitted as scattered light.
In this embodiment, the protrusion 2113 is accommodated (retracted) inside the reflection surface 2112a of the reflection mirror 2112, and a groove or hole is formed in the reflection surface 2112a of the reflection mirror 2112. The reflected light may be scattered.
　［第１６実施形態］
　図５２は、調光装置の第１６実施形態を示す概略平面図であり、調光装置を構成する光源部およびパラボラミラー形状のレンズを示す図である。
　本実施形態では、光源部２１３１が、パラボラミラー形状のレンズ２１３２内において移動可能に設けられている。すなわち、光源部２１３１は、その光の出射面２１３１ａが、レンズ２１３２の導光体（図示略）と対向する面（以下、「一方の面」と言う。）２１３２ａと同一面上となる位置から、出射面２１３１ａがレンズ２１３２の内側となる位置まで、レンズ２１３２の一方の面２１３２ａと垂直な方向に移動可能となっている。
　また、レンズ２１３２は、光源部２１３１からの光を反射する反射面２１３３ａを有する反射ミラー２１３３を備えている。
　光源部２１３１としては、上述の第９実施形態と同様のものが用いられる。
　本実施形態では、光源部２１３１からの光に指向性を変化させる配光変換素子として、レンズ２１３２を用いている。 [Sixteenth Embodiment]
FIG. 52 is a schematic plan view illustrating the sixteenth embodiment of the light control device, and is a diagram illustrating a light source unit and a parabolic mirror-shaped lens that constitute the light control device.
In the present embodiment, the light source unit 2131 is provided so as to be movable in a parabolic mirror-shaped lens 2132. That is, the light source unit 2131 has a light emission surface 2131a that is on the same plane as a surface (hereinafter referred to as “one surface”) 2132a that faces the light guide (not shown) of the lens 2132. The lens 2132 is movable in a direction perpendicular to the one surface 2132a until the exit surface 2131a is located inside the lens 2132.
The lens 2132 includes a reflection mirror 2133 having a reflection surface 2133a that reflects light from the light source unit 2131.
As the light source part 2131, the thing similar to the above-mentioned 9th Embodiment is used.
In the present embodiment, a lens 2132 is used as a light distribution conversion element that changes directivity to light from the light source unit 2131.
　光源部２１３１は、その光の出射面２１３１ａが、レンズ２１３２の導光体（図示略）と対向する面２１３２ａと同一面上に位置するときに、導光体の一端面に、出射光の焦点が合うように設けられている。したがって、この位置に光源部２１３１があるとき、光源部２１３１から導光体に入射された光は、指向性を有する光として、導光体内を伝搬する。
　一方、光源部２１３１の出射面２１３１ａが、レンズ２１３２の一方の面２１３２ａよりも内側にあるとき、光源部２１３１からの出射光の焦点は、導光体の一端面に合わない。したがって、この位置に光源部２１３１があるとき、光源部２１３１から導光体に入射された光は、散乱光として、導光体内を伝搬する。 The light source unit 2131 has a light output surface 2131a on the same surface as the surface 2132a facing the light guide (not shown) of the lens 2132, and the focus of the output light on one end surface of the light guide. Is provided to fit. Therefore, when the light source unit 2131 is located at this position, light incident on the light guide from the light source unit 2131 propagates through the light guide as directional light.
On the other hand, when the emission surface 2131a of the light source unit 2131 is inside the one surface 2132a of the lens 2132, the focus of the emission light from the light source unit 2131 does not match the one end surface of the light guide. Therefore, when the light source unit 2131 is present at this position, the light incident on the light guide from the light source unit 2131 propagates through the light guide as scattered light.
　［第１７実施形態］
　図５３は、調光装置の第１７実施形態を示す概略断面図である。
　調光装置２１４０は、光源部２１４１と、導光体２１４２と、反射ミラー２１４３を備えたパラボラミラー形状のレンズ２１４４とから概略構成されている。導光体２１４２は、光源部２１４１に対向して配置される。導光体２１４２は、光源部２１４１からの光がその一端面２１４２ａ側から導入されるとともに、光源部２１４１からの光をその長手方向に導光する。パラボラミラー形状のレンズ２１４４は、光源部２１４１の導光体２１４２の一端面２１４２ａと対向する面２１４１ａとは反対の面側に設けられる。反射ミラー２１４３は、光源部２１４１からの光を反射する反射面２１４３ａを有する。
　調光装置２１４０では、導光体２１４２とレンズ２１４４とが、光源部２１４１を介して対向するように配設されている。すなわち、導光体２１４２とレンズ２１４４との間には、光源部２１４１の厚さによる隙間が形成されている。そして、その隙間を通して、光源部２１４１の配線２１４５，２１４６が電源（図示略）に接続されている。
　本実施形態では、光源部２１４１からの光に指向性を変化させる配光変換素子として、レンズ２１４４を用いている。 [Seventeenth embodiment]
FIG. 53 is a schematic sectional view showing a seventeenth embodiment of the light control device.
The light control device 2140 is generally configured by a light source unit 2141, a light guide 2142, and a parabolic mirror-shaped lens 2144 including a reflection mirror 2143. The light guide 2142 is disposed to face the light source unit 2141. The light guide 2142 guides the light from the light source unit 2141 in the longitudinal direction while the light from the light source unit 2141 is introduced from the one end surface 2142a side. The parabolic mirror-shaped lens 2144 is provided on the side opposite to the surface 2141a facing the one end surface 2142a of the light guide 2142 of the light source unit 2141. The reflection mirror 2143 has a reflection surface 2143 a that reflects light from the light source unit 2141.
In the light control device 2140, the light guide 2142 and the lens 2144 are arranged so as to face each other with the light source unit 2141 interposed therebetween. That is, a gap due to the thickness of the light source unit 2141 is formed between the light guide 2142 and the lens 2144. The wirings 2145 and 2146 of the light source unit 2141 are connected to a power source (not shown) through the gap.
In this embodiment, a lens 2144 is used as a light distribution conversion element that changes the directivity of light from the light source unit 2141.
　また、光源部２１４１は、レンズ２１４４の導光体２１４２と対向する面（以下、「一方の面」と言う。）２１４４ａの中央部に配設されている。そして、光源部２１４１を中心として、レンズ２１４４は回転可能となっている。 The light source unit 2141 is disposed at the center of a surface (hereinafter referred to as “one surface”) 2144a of the lens 2144 facing the light guide 2142. The lens 2144 is rotatable around the light source unit 2141.
　光源部２１４１、導光体２１４２、反射ミラー２１４３、レンズ２１４４としては、上述の第９実施形態と同様のものが用いられる。 As the light source unit 2141, the light guide 2142, the reflection mirror 2143, and the lens 2144, the same ones as those in the ninth embodiment described above are used.
　本実施形態では、図５４Ａに示すように、光源部２１４１の長手方向が、レンズ２１４４の突出面を横切る断面と垂直に交わるときに、導光体２１４２の一端面２１４２ａに、光源部２１４１の出射光の焦点が合うようになっている。したがって、この位置にレンズ２１４４があるとき、光源部２１４１から導光体２１４２に入射された光は、指向性を有する光として、導光体２１４２内を伝搬する。
　一方、図５４Ｂに示すように、光源部２１４１の長手方向が、レンズ２１４４の突出面を横切る断面と平行であるとき、光源部２１４１からの出射光の焦点は、導光体２１４２の一端面２１４２ａに合わない。したがって、この位置にレンズ２１４４があるとき、光源部２１４１から導光体２１４２に入射された光は、散乱光として、導光体２１４２内を伝搬する。 In this embodiment, as shown in FIG. 54A, when the longitudinal direction of the light source unit 2141 intersects the cross section perpendicular to the projecting surface of the lens 2144 perpendicularly, the light source unit 2141 protrudes from the one end surface 2142a of the light guide 2142. The incident light is in focus. Therefore, when the lens 2144 is present at this position, light incident on the light guide 2142 from the light source unit 2141 propagates in the light guide 2142 as directional light.
On the other hand, as shown in FIG. 54B, when the longitudinal direction of the light source unit 2141 is parallel to the cross section crossing the protruding surface of the lens 2144, the focal point of the emitted light from the light source unit 2141 is the one end surface 2142a of the light guide 2142. Does not fit. Therefore, when the lens 2144 is present at this position, light incident on the light guide 2142 from the light source unit 2141 propagates in the light guide 2142 as scattered light.
　［第１８実施形態］
　図５５は、調光装置の第１８実施形態を示す概略断面図である。
　調光装置２１５０は、光源部２１５１と、導光体２１５２と、反射ミラー２１５３を備えたパラボラミラー形状のレンズ２１５４とから概略構成されている。導光体２１５２は、光源部２１５１に対向して配置される。導光体２１５２は、光源部２１５１からの光がその一端面２１５２ａ側から導入されるとともに、光源部２１５１からの光をその長手方向に導光する。パラボラミラー形状のレンズ２１５４は、光源部２１５１の導光体２１５２の一端面２１５２ａと対向する面２１５１ａとは反対の面側に設けられる。反射ミラー２１５３は、光源部２１５１からの光を反射する反射面２１５３ａを有する。
　調光装置２１５０では、導光体２１５２とレンズ２１５４とが、光源部２１５１を介して対向するように配設されている。すなわち、導光体２１５２とレンズ２１５４との間には、光源部２１５１の厚さによる隙間が形成されている。そして、その隙間を通して、光源部２１５１の配線２１５５，２１５６が電源（図示略）に接続されている。
　本実施形態では、光源部２１５１からの光に指向性を変化させる配光変換素子として、レンズ２１５４を用いている。 [Eighteenth embodiment]
FIG. 55 is a schematic sectional view showing an eighteenth embodiment of the light control device.
The light control device 2150 is generally configured by a light source unit 2151, a light guide 2152, and a parabolic mirror-shaped lens 2154 including a reflection mirror 2153. The light guide 2152 is disposed to face the light source unit 2151. The light guide 2152 guides the light from the light source 2151 in the longitudinal direction while the light from the light source 2151 is introduced from the one end face 2152a side. The parabolic mirror-shaped lens 2154 is provided on the surface opposite to the surface 2151 a facing the one end surface 2152 a of the light guide 2152 of the light source unit 2151. The reflection mirror 2153 has a reflection surface 2153 a that reflects light from the light source unit 2151.
In the light control device 2150, the light guide 2152 and the lens 2154 are disposed so as to face each other with the light source unit 2151 interposed therebetween. That is, a gap due to the thickness of the light source unit 2151 is formed between the light guide 2152 and the lens 2154. The wirings 2155 and 2156 of the light source unit 2151 are connected to a power source (not shown) through the gap.
In the present embodiment, a lens 2154 is used as a light distribution conversion element that changes the directivity to light from the light source unit 2151.
　また、光源部２１５１は、レンズ２１５４の導光体２１５２と対向する面（以下、「一方の面」と言う。）２１５４ａの中央部に配設されている。そして、光源部２１５１は、レンズ２１５４の一方の面２１５４ａ上において、回転可能となっている。 The light source unit 2151 is disposed at the center of a surface (hereinafter referred to as “one surface”) 2154a of the lens 2154 facing the light guide 2152. The light source unit 2151 is rotatable on one surface 2154a of the lens 2154.
　光源部２１５１、導光体２１５２、反射ミラー２１５３、レンズ２１５４としては、上述の第９実施形態と同様のものが用いられる。 As the light source unit 2151, the light guide body 2152, the reflection mirror 2153, and the lens 2154, the same ones as those in the ninth embodiment described above are used.
　本実施形態では、図５６Ａに示すように、光源部２１５１の長手方向が、レンズ２１５４の突出面を横切る断面と垂直に交わるときに、導光体２１５２の一端面２１５２ａに、光源部２１５１の出射光の焦点が合うようになっている。したがって、この位置にレンズ２１５４があるとき、光源部２１５１から導光体２１５２に入射された光は、指向性を有する光として、導光体２１５２内を伝搬する。
　一方、図５６Ｂに示すように、光源部２１５１の長手方向が、レンズ２１５４の突出面を横切る断面と平行であるとき、光源部２１５１からの出射光の焦点は、導光体２１５２の一端面２１５２ａに合わない。したがって、この位置にレンズ２１５４があるとき、光源部２１５１から導光体２１５２に入射された光は、散乱光として、導光体２１５２内を伝搬する。 In the present embodiment, as shown in FIG. 56A, when the longitudinal direction of the light source unit 2151 intersects the cross section perpendicular to the projecting surface of the lens 2154 perpendicularly, the light source unit 2151 protrudes from the one end surface 2152a of the light guide 2152. The incident light is in focus. Therefore, when the lens 2154 is present at this position, light incident on the light guide 2152 from the light source unit 2151 propagates in the light guide 2152 as directional light.
On the other hand, as shown in FIG. 56B, when the longitudinal direction of the light source unit 2151 is parallel to the cross section crossing the protruding surface of the lens 2154, the focal point of the emitted light from the light source unit 2151 is one end surface 2152a of the light guide 2152a. Does not fit. Therefore, when the lens 2154 is at this position, the light incident on the light guide 2152 from the light source unit 2151 propagates in the light guide 2152 as scattered light.
　［第１９実施形態］
　図５７Ａおよび図５７Ｂは、調光装置の第１９実施形態を示す概略図であり、図５７Ａは平面図である。図５７Ｂは、図５７ＡのＥ２－Ｅ２線に沿う断面図である。
　調光装置２１６０は、光源部２１６１と、楔形状の導光体２１６２と、散乱液晶セル２１６３と、反射ミラー２１６４を備えたパラボラミラー形状のレンズ２１６５と、プリズム２１６６とから概略構成されている。楔形状の導光体２１６２は、光源部２１６１に対向して配置される。楔形状の導光体２１６２は、光源部２１６１からの光がその一端面２１６２ａ側から導入されるとともに、光源部２１６１からの光をその長手方向に導光する。散乱液晶セル２１６３は、光源部２１６１と導光体２１６２の一端面２１６２ａとの間に設けられる。パラボラミラー形状のレンズ２１６５は、光源部２１６１の導光体２１６２の一端面２１６２ａと対向する面２１６１ａとは反対の面側に設けられる。反射ミラー２１６４は、光源部２１６１からの光を反射する反射面２１６４ａを有する。プリズム２１６６は、レンズ２１６５の上面２１６５ｂ上に設けられる。プリズム２１６６は、その上面２１６５ｂと対向する面２１６６ａが鋸刃形状をなす。
　本実施形態では、光源部２１６１からの光に指向性を変化させる配光変換素子として、散乱液晶セル２１６３を用いている。 [Nineteenth Embodiment]
57A and 57B are schematic views showing a nineteenth embodiment of the light control device, and FIG. 57A is a plan view. FIG. 57B is a cross-sectional view taken along line E2-E2 of FIG. 57A.
The light control device 2160 is generally configured by a light source unit 2161, a wedge-shaped light guide 2162, a scattering liquid crystal cell 2163, a parabolic mirror-shaped lens 2165 including a reflection mirror 2164, and a prism 2166. The wedge-shaped light guide 2162 is disposed to face the light source portion 2161. The wedge-shaped light guide 2162 introduces the light from the light source 2161 from the one end face 2162a side and guides the light from the light source 2161 in the longitudinal direction. The scattering liquid crystal cell 2163 is provided between the light source unit 2161 and the one end surface 2162a of the light guide 2162. The parabolic mirror-shaped lens 2165 is provided on the surface opposite to the surface 2161a facing the one end surface 2162a of the light guide 2162 of the light source unit 2161. The reflection mirror 2164 has a reflection surface 2164 a that reflects light from the light source unit 2161. The prism 2166 is provided on the upper surface 2165b of the lens 2165. In the prism 2166, a surface 2166a facing the upper surface 2165b has a saw blade shape.
In the present embodiment, a scattering liquid crystal cell 2163 is used as a light distribution conversion element that changes the directivity to light from the light source unit 2161.
　導光体２１６２は、ガラス、石英などからなる無機材料、ポリメタクリル酸メチル（ポリメチルメタクリレート、ＰＭＭＡ）などからなるプラスチックなどの光透過性の材料から構成されている。 The light guide 2162 is made of a light-transmitting material such as an inorganic material made of glass, quartz, or the like, or a plastic made of polymethyl methacrylate (polymethyl methacrylate, PMMA) or the like.
　プリズム２１６６は、ガラス、石英などからなる無機材料、ポリメタクリル酸メチル（ポリメチルメタクリレート、ＰＭＭＡ）などからなるプラスチックなどの光透過性の材料から構成されている。 The prism 2166 is made of a light-transmitting material such as an inorganic material made of glass, quartz or the like, or a plastic made of polymethyl methacrylate (polymethyl methacrylate, PMMA) or the like.
　光源部２１６１、散乱液晶セル２１６３、反射ミラー２１６４としては、上述の第９実施形態と同様のものが用いられる。 As the light source unit 2161, the scattering liquid crystal cell 2163, and the reflection mirror 2164, the same ones as in the ninth embodiment are used.
　調光装置２１６０では、例えば、散乱液晶セル２１６３を構成する液晶を配向させた状態で、光源部２１６１からの光が、反射ミラー２１６４の反射面２１６４ａで反射して、その反射光が、散乱液晶セル２１６３に入射すると、反射光は散乱液晶セル２１６３内の液晶によって散乱されることなく、指向性を有する光として、一端面２１６２ａから導光体２１６２に入射する。このとき、導光体２１６２に入射した光は、導光体２１６２の幅方向に広がりをもたない光となっている。そして、この導光体２１６２に入射した光は、導光体２１６２の上面２１６２ｂと斜面２１６２ｃで反射を繰り返して、導光体２１６２内を伝搬するに従って、導光体２１６２の厚さ方向にも広がりをもたない光となる。したがって、導光体２１６２の上面２１６２ｂから出射する光は、導光体２１６２の幅方向および厚さ方向に拡がることなく、狭い出射角で出射する。導光体２１６２の上面２１６２ｂから出射する光の出射角は、例えば、図７に示すように、導光体２１６２の幅方向および厚さ方向において、極めて狭くなる。 In the light control device 2160, for example, in a state where the liquid crystal constituting the scattering liquid crystal cell 2163 is aligned, the light from the light source unit 2161 is reflected by the reflecting surface 2164a of the reflecting mirror 2164, and the reflected light is scattered liquid crystal. When entering the cell 2163, the reflected light is not scattered by the liquid crystal in the scattering liquid crystal cell 2163 but enters the light guide 2162 from one end surface 2162 a as directional light. At this time, the light incident on the light guide 2162 is light that does not spread in the width direction of the light guide 2162. The light incident on the light guide 2162 is repeatedly reflected on the upper surface 2162b and the slope 2162c of the light guide 2162, and spreads in the thickness direction of the light guide 2162 as it propagates in the light guide 2162. The light has no light. Therefore, the light emitted from the upper surface 2162b of the light guide 2162 is emitted at a narrow emission angle without spreading in the width direction and the thickness direction of the light guide 2162. For example, as shown in FIG. 7, the emission angle of light emitted from the upper surface 2162b of the light guide 2162 becomes extremely narrow in the width direction and the thickness direction of the light guide 2162.
　［第２０実施形態］
　図５８Ａおよび図５８Ｂは、調光装置の第２０実施形態を示す概略平面図である。図５８Ａは、全体図である。図５８Ｂは、図５８Ａにおいて破線αで囲んだ領域を拡大した図である。
　調光装置２１７０は、光源部２１７１と、導光体２１７２と、エレクトロクロミックミラー２１７３を備えたパラボラミラー形状のレンズ２１７４と、反射手段２１７５とから概略構成されている。導光体２１７２は、光源部２１７１に対向して配置される。導光体２１７２は、光源部２１７１からの光がその一端面２１７２ａ側から導入されるとともに、光源部２１７１からの光をその長手方向に導光する。パラボラミラー形状のレンズ２１７４は、光源部２１７１の導光体２１７２の一端面２１７２ａと対向する面２１７１ａとは反対の面側に設けられる。エレクトロクロミックミラー２１７３は、光源部２１７１からの光を反射する反射面２１７３ａを有する。反射手段２１７５は、エレクトロクロミックミラー２１７３の光源部２１７１と対向する面とは反対の面側に設けられる。反射手段２１７５は、エレクトロクロミックミラー２１７３を透過した光を反射する。
　また、光源部２１７１、エレクトロクロミックミラー２１７３、レンズ２１７４および反射手段２１７５からなる単位が、導光体２１７２の一端面２１７２ａに沿って複数設けられている。
　本実施形態では、光源部２１７１からの光に指向性を変化させる配光変換素子として、エレクトロクロミックミラー２１７３を備えたレンズ２１７４を用いている。 [20th embodiment]
58A and 58B are schematic plan views showing the twentieth embodiment of the light control device. FIG. 58A is an overall view. 58B is an enlarged view of a region surrounded by a broken line α in FIG. 58A.
The light control device 2170 is generally configured by a light source unit 2171, a light guide 2172, a parabolic mirror-shaped lens 2174 including an electrochromic mirror 2173, and a reflection unit 2175. The light guide 2172 is disposed to face the light source unit 2171. The light guide 2172 guides the light from the light source part 2171 in the longitudinal direction while the light from the light source part 2171 is introduced from the one end face 2172a side. The parabolic mirror-shaped lens 2174 is provided on the surface opposite to the surface 2171a facing the one end surface 2172a of the light guide 2172 of the light source unit 2171. The electrochromic mirror 2173 has a reflection surface 2173a that reflects light from the light source unit 2171. The reflection means 2175 is provided on the surface of the electrochromic mirror 2173 opposite to the surface facing the light source unit 2171. The reflection means 2175 reflects the light transmitted through the electrochromic mirror 2173.
Further, a plurality of units each including a light source unit 2171, an electrochromic mirror 2173, a lens 2174, and a reflection unit 2175 are provided along the one end surface 2172 a of the light guide 2172.
In this embodiment, a lens 2174 provided with an electrochromic mirror 2173 is used as a light distribution conversion element that changes the directivity of light from the light source unit 2171.
　エレクトロクロミックミラー２１７３は、電界の印加により、反射面２１７３ａにおける光の反射と透過を切り替えることができるものである。 The electrochromic mirror 2173 can switch between reflection and transmission of light on the reflection surface 2173a by application of an electric field.
　反射手段２１７５の内側面２１７５ａ、２１７５ｂ、２１７５ｃには、一般的な鏡（反射ミラー）が設けられているか、あるいは、上述の第１１実施形態と同様に散乱体が設けられている。これにより、光源部２１７１から発せられ、エレクトロクロミックミラー２１７３を透過した光を、導光体２１７２側に反射することができる。 A general mirror (reflection mirror) is provided on the inner side surfaces 2175a, 2175b, and 2175c of the reflection means 2175, or a scatterer is provided as in the above-described eleventh embodiment. Thereby, the light emitted from the light source unit 2171 and transmitted through the electrochromic mirror 2173 can be reflected to the light guide 2172 side.
　光源部２１７１、導光体２１７２、２レンズ１７４としては、上述の第９実施形態と同様のものが用いられる。 As the light source unit 2171, the light guide 2172, and the second lens 174, the same ones as those in the ninth embodiment described above are used.
　反射手段２１７５は、ガラス、石英などからなる無機材料、ポリメタクリル酸メチル（ポリメチルメタクリレート、ＰＭＭＡ）などからなるプラスチックなどの光透過性の材料から構成されている。また、反射手段２１７５は、外側の骨格部分が前記の材料からなり、内部が中空構造をなしていてもよく、あるいは、全体が前記の材料からなる中実構造をなしていてもよい。 The reflecting means 2175 is made of a light transmissive material such as an inorganic material made of glass, quartz, or the like, or a plastic made of polymethyl methacrylate (polymethyl methacrylate, PMMA) or the like. Further, the reflecting means 2175 may have an outer skeleton portion made of the above-mentioned material and an inside having a hollow structure, or may have a solid structure made entirely of the above-described material.
　図５９Ａは、エレクトロクロミックミラー２１７３に電圧を印加した場合、調光装置を用いた状態を示す概略平面図である。
　このとき、光源部２１７１からの光が、エレクトロクロミックミラー２１７３の反射面２１７３ａで反射して、その反射光が、反射手段２１７５の内側面２１７５ａ、２１７５ｂ、２１７５ｃに設けられた鏡や散乱体によって散乱されず、指向性を有する光として、一端面２１７２ａから導光体２１７２に入射する。したがって、導光体２１７２の上面２１７２ｂから出射する光は、導光体２１７２の幅方向に拡がることなく、狭い出射角で出射する。 FIG. 59A is a schematic plan view showing a state in which the light control device is used when a voltage is applied to the electrochromic mirror 2173. FIG.
At this time, light from the light source unit 2171 is reflected by the reflection surface 2173a of the electrochromic mirror 2173, and the reflected light is scattered by mirrors and scatterers provided on the inner surfaces 2175a, 2175b, and 2175c of the reflection means 2175. Instead, the light enters the light guide 2172 from the one end surface 2172a as light having directivity. Therefore, the light emitted from the upper surface 2172b of the light guide 2172 is emitted at a narrow emission angle without spreading in the width direction of the light guide 2172.
　図５９Ｂは、エレクトロクロミックミラー２１７３に電圧を印加しない場合、調光装置を用いた状態を示す概略平面図である。
　このとき、光源部２１７１からの光が、エレクトロクロミックミラー２１７３を透過して、その透過光が、反射手段２１７５の内側面２１７５ａ、２１７５ｂ、２１７５ｃに設けられた鏡や散乱体によって散乱され、散乱光となって、一端面２１７２ａから導光体２１７２に入射する。したがって、導光体２１７２の上面２１７２ｂから出射する光は、導光体２１７２の幅方向に拡がり、広い出射角で出射する。 FIG. 59B is a schematic plan view showing a state in which the light control device is used when no voltage is applied to the electrochromic mirror 2173.
At this time, light from the light source unit 2171 passes through the electrochromic mirror 2173, and the transmitted light is scattered by mirrors and scatterers provided on the inner side surfaces 2175a, 2175b, and 2175c of the reflecting means 2175, and the scattered light. Then, the light enters the light guide 2172 from the one end surface 2172a. Therefore, the light emitted from the upper surface 2172b of the light guide 2172 spreads in the width direction of the light guide 2172 and is emitted with a wide emission angle.
［第２１実施形態］
　以下、本発明の第２１実施形態について、図３１、図６０、図６３を用いて説明する。
　第２１実施形態では、上記実施形態の面光源装置を備えた表示装置の一例を示す。本実施形態は、第１実施形態の面光源装置をバックライトとして備えた液晶表示装置の一例である。 [Twenty-first embodiment]
Hereinafter, a twenty-first embodiment of the present invention will be described with reference to FIGS. 31, 60, and 63. FIG.
In the twenty-first embodiment, an example of a display device including the surface light source device of the above embodiment is shown. The present embodiment is an example of a liquid crystal display device that includes the surface light source device of the first embodiment as a backlight.
　本実施形態の液晶表示装置１６５は、図３１および図６０に示すように、バックライト１６６（面光源装置）と、第１偏光板１６７と、液晶パネル（液晶セルともいう）１６８と、第２偏光板１６９と、から構成されている。バックライト１６６は、液晶パネル１６８の表示画面１６８ａとは反対側の面１６８ｂ側に配置される。なお、図３１では、液晶パネル１６８を模式的に１枚の板状に図示している。観察者は、第２偏光板１６９が配置された図３１における液晶表示装置１６５の上側から表示を見ることになる。よって、以下の説明では、第２偏光板１６９が配置された側を視認側と称し、バックライト１６６が配置された側を背面側と称する。
　液晶表示装置１６５において、バックライト１６６は、上述の第１実施形態～第２０実施形態の調光装置のいずれかから構成されている。 As shown in FIGS. 31 and 60, the liquid crystal display device 165 of this embodiment includes a backlight 166 (surface light source device), a first polarizing plate 167, a liquid crystal panel (also referred to as a liquid crystal cell) 168, a second A polarizing plate 169. The backlight 166 is disposed on the surface 168b side of the liquid crystal panel 168 opposite to the display screen 168a. In FIG. 31, the liquid crystal panel 168 is schematically illustrated as a single plate. The observer views the display from the upper side of the liquid crystal display device 165 in FIG. 31 in which the second polarizing plate 169 is disposed. Therefore, in the following description, the side on which the second polarizing plate 169 is disposed is referred to as a viewing side, and the side on which the backlight 166 is disposed is referred to as a back side.
In the liquid crystal display device 165, the backlight 166 is composed of any of the light control devices of the first to twentieth embodiments described above.
　本実施形態の液晶表示装置１６５においては、バックライト１６６から射出された光を液晶パネル１６８で変調し、変調した光によって所定の画像や文字等を表示する。
　液晶パネル１６８としては、例えばアクティブマトリクス方式の透過型液晶パネルを用いることができる。ただし、アクティブマトリクス方式の透過型液晶パネルに限らず、例えば半透過型（透過・反射兼用型）液晶パネル、各画素がスイッチング用薄膜トランジスタ（Ｔｈｉｎ　Ｆｉｌｍ　Ｔｒａｎｓｉｓｔｏｒ, 以下、ＴＦＴと略記する）を備えていない単純マトリクス方式の液晶パネルであっても良い。液晶パネル１６８には周知の一般的な液晶パネルを用いることができるため、詳細な構成の説明は省略する。 In the liquid crystal display device 165 of this embodiment, the light emitted from the backlight 166 is modulated by the liquid crystal panel 168, and a predetermined image, characters, or the like is displayed by the modulated light.
As the liquid crystal panel 168, for example, an active matrix transmissive liquid crystal panel can be used. However, the liquid crystal panel is not limited to an active matrix transmissive liquid crystal panel, and does not include, for example, a transflective (transmissive / reflective) liquid crystal panel and each pixel includes a switching thin film transistor (hereinafter abbreviated as TFT). A simple matrix type liquid crystal panel may be used. Since a known general liquid crystal panel can be used for the liquid crystal panel 168, a detailed description of the configuration is omitted.
　本構成例の液晶テレビジョン１７０は、図６３に示すように、表示画面として本実施形態の液晶表示装置１６５を備えている。観察者側（図６３の手前側）には液晶パネル１６８が配置され、観察者と反対側（図６３の奥側）にはバックライト１６６（面光源装置）が配置されている。 As shown in FIG. 63, the liquid crystal television 170 of this configuration example includes the liquid crystal display device 165 of this embodiment as a display screen. A liquid crystal panel 168 is disposed on the viewer side (front side in FIG. 63), and a backlight 166 (surface light source device) is disposed on the side opposite to the viewer (back side in FIG. 63).
　本実施形態の液晶表示装置１６５では、指向性の切り替えが可能な第１実施形態の面光源装置１１からなるバックライト１６６を用いている。そのため、バックライト１６６を高指向性モードとすることにより、液晶表示装置１６５の視聴者側（液晶パネル１６８の表示画面１６８ａ側）に出射される光が拡散することがないので、例えば一人の観察者が画面の正面から液晶テレビジョンを見る際に好適なものとなる。また、バックライト１６６を広角モードとすることにより、表示装置１６５の視聴者側（液晶セル１６８の表示画面１６８ａ側）に出射される光が拡散するので、視野角を広げることができる。この場合、例えば多くの観察者が画面の様々な方向から液晶テレビジョンを見る際に好適なものとなる。
　すなわち、バックライト１６６として、上述の第１実施形態～第２０実施形態の調光装置のいずれかを用いることにより、表示装置１６５の視野角を調整することができる。 In the liquid crystal display device 165 of this embodiment, a backlight 166 including the surface light source device 11 of the first embodiment capable of switching directivity is used. Therefore, by setting the backlight 166 to the high directivity mode, light emitted to the viewer side of the liquid crystal display device 165 (the display screen 168a side of the liquid crystal panel 168) is not diffused. This is suitable when a person watches a liquid crystal television from the front of the screen. Further, by setting the backlight 166 to the wide angle mode, light emitted to the viewer side of the display device 165 (the display screen 168a side of the liquid crystal cell 168) is diffused, so that the viewing angle can be widened. In this case, for example, it is suitable when many observers watch the liquid crystal television from various directions on the screen.
That is, the viewing angle of the display device 165 can be adjusted by using any one of the dimming devices of the first to twentieth embodiments described above as the backlight 166.
［第２２実施形態］
　以下、本発明の第２２実施形態について、図６１～図６６Ｂを用いて説明する。
　第２２実施形態では、上記実施形態の面光源装置を備えた照明装置の一例を示す。 [Twenty-second embodiment]
Hereinafter, a twenty-second embodiment of the present invention will be described with reference to FIGS. 61 to 66B.
In the twenty-second embodiment, an example of a lighting device including the surface light source device of the above-described embodiment is shown.
　図６４Ａは、上記実施形態の光源部を備えた電気スタンド１７５を示している。図６４Ｂは、電気スタンド１７５の光源部１２を示しており、高指向性用光源部１１３と広角用光源部１１４とを備えている。この電気スタンド１７５では、光源部１２を高指向性モードとすることにより、図６４Ａに実線の矢印で示すように、狭い範囲を照明することができる。光源部１２を広角モードとすることにより、図６４Ｂに破線の矢印で示すように、広い範囲を照明することができる。 FIG. 64A shows a table lamp 175 provided with the light source unit of the above embodiment. FIG. 64B shows the light source unit 12 of the desk lamp 175, which includes a high directivity light source unit 113 and a wide-angle light source unit 114. In the desk lamp 175, by setting the light source unit 12 in the high directivity mode, a narrow range can be illuminated as shown by a solid arrow in FIG. 64A. By setting the light source unit 12 to the wide-angle mode, a wide range can be illuminated as shown by the dashed arrows in FIG. 64B.
　図６５Ａは、照射面が円形の光源部１２ａを備えた電気スタンド１７６を示している。
図６５Ｂは、電気スタンド１７６の光源部１２ａを示しており、円形の凹面ミラーを有する高指向性光源部１１３ａと広角用光源部１１４ａとを備えている。この電気スタンド１７６では、光源部１２ａを高指向性モードとすることにより、図６５Ａに１点鎖線の矢印で示すように、狭い範囲を照明することができる。光源部１１２ａを広角モードとすることにより、図６５Ａに破線の矢印で示すように、広い範囲を照明することができる。 FIG. 65A shows a table lamp 176 provided with a light source unit 12a having a circular irradiation surface.
FIG. 65B shows the light source unit 12a of the desk lamp 176, which includes a highly directional light source unit 113a having a circular concave mirror and a wide-angle light source unit 114a. In the desk lamp 176, by setting the light source unit 12a to the high directivity mode, a narrow range can be illuminated as shown by the dashed-dotted arrow in FIG. 65A. By setting the light source unit 112a to the wide-angle mode, a wide range can be illuminated as shown by the dashed arrows in FIG. 65A.
本実施形態の証明スタンドは、図６２に示す形態でもよい。図６２は、照明装置の一実施形態として、照明スタンドを示す概略斜視図である。
　照明スタンド２２００は、発光部２２０１と、スタンド２２０２と、メインスイッチ２２０３と、電源コード２２０４とから概略構成されている。
　照明スタンド２２００において、発光部２２０１は、上述の第1実施形態～第２０実施形態の調光装置のいずれかから構成されている。 The form shown in FIG. 62 may be sufficient as the proof stand of this embodiment. FIG. 62 is a schematic perspective view showing a lighting stand as an embodiment of the lighting device.
The illumination stand 2200 is generally configured by a light emitting unit 2201, a stand 2202, a main switch 2203, and a power cord 2204.
In the illumination stand 2200, the light emitting unit 2201 is configured from any of the light control devices of the first to twentieth embodiments described above.
　照明スタンド２２００は、上述の第１実施形態～第２０実施形態の調光装置を発光部２２０１として備えることにより、光の照射する領域を調節可能な照明装置となる。 The illumination stand 2200 is an illumination device that can adjust the light irradiation region by including the light control device of the first to twentieth embodiments described above as the light emitting unit 2201.
　図６６Ａ、図６６Ｂは、上記実施形態の面光源装置を備えたシーリングライト１７７を示している。このシーリングライト１７７では、面光源装置を高指向性モードとすることにより、図６６Ａに示すように、狭い範囲を照明することができる。面光源装置を広角モードとすることにより、図６６Ｂに示すように、広い範囲を照明することができる。 66A and 66B show a ceiling light 177 provided with the surface light source device of the above embodiment. With this ceiling light 177, by setting the surface light source device in the high directivity mode, it is possible to illuminate a narrow range as shown in FIG. 66A. By setting the surface light source device to the wide angle mode, a wide range can be illuminated as shown in FIG. 66B.
　以上のように、上記の光源部だけで照明装置を構成してもよいし、面光源装置で照明装置を構成してもよい。上記の光源部や面光源装置を照明装置として用いる場合、表示装置として用いる場合に比べて高い指向性は要求されない。したがって、光の出力を高めるために、大きめの光源を用いることができる。 As described above, the illuminating device may be configured with only the light source unit described above, or the illuminating device may be configured with a surface light source device. When the light source unit or the surface light source device is used as a lighting device, high directivity is not required as compared with the case of using it as a display device. Therefore, a larger light source can be used to increase the light output.
本実施形態のシーリングライトは、図６１に示す形態であってもよい。図６１は、照明装置の一実施形態として、シーリングライトを示す概略斜視図である。
　シーリングライト２１９０は、発光部２１９１と、吊下線２１９２と、電源コード２１９３とから概略構成されている。
　シーリングライト２１９０において、発光部２１９１は、上述の第１実施形態～第２０実施形態の調光装置のいずれかから構成されている。 The ceiling light of this embodiment may have the form shown in FIG. FIG. 61 is a schematic perspective view showing a ceiling light as one embodiment of a lighting device.
The ceiling light 2190 includes a light emitting unit 2191, a hanging line 2192, and a power cord 2193.
In the ceiling light 2190, the light emitting unit 2191 is composed of any of the light control devices of the first to twentieth embodiments described above.
　シーリングライト２１９０は、上述の第１実施形態～第２０実施形態の調光装置を発光部２１９１として備えることにより、光の照射する領域を調節可能な照明装置となる。 The ceiling light 2190 is an illuminating device that can adjust the region irradiated with light by including the light control device of the first to twentieth embodiments described above as the light emitting unit 2191.
　なお、本発明の態様における技術範囲は上記実施形態に限定されるものではなく、本発明の態様における趣旨を逸脱しない範囲において種々の変更を加えることが可能である。
　例えば上記第１実施形態～第４実施形態、第９実施形態、第１１実施形態～第１２実施形態、第１４実施形態～第２０実施形態においては、凹面ミラーやレンズの形状はパラボラ面を有すると述べた。これに対し、上記の実施形態で用いることが可能な凹面ミラーやレンズの有する形状は、必ずしもパラボラ面に限ることなく、放物面を含む概念として円錐曲面であれば良い。円錐曲面の頂点を通る断面の形状を示す曲線は二次曲線と呼ばれる。二次曲線は、円錐を任意の平面で切り取った断面から得られる曲線である。凹面ミラーの径方向の座標をρ、凹面ミラーの中心軸方向の座標をｚ、コーニック係数をｋとすると、二次曲線を下記の（１）式、（２）式で表すことができる。 The technical scope in the aspect of the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the aspect of the present invention.
For example, in the first embodiment to the fourth embodiment, the ninth embodiment, the eleventh embodiment to the twelfth embodiment, and the fourteenth embodiment to the twentieth embodiment, the concave mirror and the lens have a parabolic surface. I said. On the other hand, the shape of the concave mirror or lens that can be used in the above embodiment is not necessarily limited to a parabolic surface, but may be a conical curved surface as a concept including a paraboloid. A curve indicating the shape of a cross section passing through the apex of the conical curved surface is called a quadratic curve. A quadratic curve is a curve obtained from a cross section obtained by cutting a cone at an arbitrary plane. When the coordinate in the radial direction of the concave mirror is ρ, the coordinate in the central axis direction of the concave mirror is z, and the conic coefficient is k, the quadratic curve can be expressed by the following equations (1) and (2).
Figure JPOXMLDOC01-appb-M000001
Figure JPOXMLDOC01-appb-M000001
Figure JPOXMLDOC01-appb-M000002
Figure JPOXMLDOC01-appb-M000002
　（１）式、（２）式におけるコーニック係数ｋの値によって二次曲線の形状は変化する。二次曲線は、例えばｋ＝０のときに円となり、ｋ＝－０．２５のときに楕円曲線となり、ｋ＝－１のときに放物線となり、ｋ＝－２のときに双曲線となる。上記の実施形態では、これらの二次曲線をｘｙ平面における断面形状とする凹面ミラーを用いることができる。なお、第１実施形態でも述べたように、ＬＥＤからの光が到達する領域が少なくとも円錐曲面であれば良いので、ＬＥＤからの光が到達しない領域は例えば平坦な面であっても良い。 The shape of the quadratic curve changes depending on the value of the conic coefficient k in the equations (1) and (2). The quadratic curve is, for example, a circle when k = 0, an elliptic curve when k = −0.25, a parabola when k = −1, and a hyperbola when k = −2. In the above embodiment, it is possible to use a concave mirror having these quadratic curves as cross-sectional shapes in the xy plane. As described in the first embodiment, the region where the light from the LED reaches may be at least a conical curved surface, and the region where the light from the LED does not reach may be, for example, a flat surface.
　また、凹面ミラーの内部に配置されたシリンドリカルレンズはなくてもよい。シリンドリカルレンズが配置されていた部分が中空であってもよい。その他、上記実施形態で例示した面光源装置の各構成要素の形状、数、配置、材質等に関しては、適宜変更が可能である。例えば、導光体、凹面ミラー、楔形導光棒等の部材には種々の材料を用いることができるが、これらの光源と接する部材には、耐熱性の高い材料を用いることが望ましい。 Also, there may be no cylindrical lens disposed inside the concave mirror. The portion where the cylindrical lens is disposed may be hollow. In addition, the shape, number, arrangement, material, and the like of each component of the surface light source device exemplified in the above embodiment can be appropriately changed. For example, various materials can be used for members such as a light guide, a concave mirror, and a wedge-shaped light guide rod, but it is desirable to use a material having high heat resistance for the members in contact with these light sources.
　本発明のいくつかの態様は、液晶表示装置、有機エレクトロルミネッセンス表示装置、プラズマディスプレイなどの各種表示装置、もしくはこれらの表示装置に用いられる面光源装置に利用可能であり、これらの表示装置の視野角を拡大する調光装置として利用することができる。もしくは光の照射する領域を調節可能な照明装置等の各種照明装置に利用可能である。 Some embodiments of the present invention can be used in various display devices such as liquid crystal display devices, organic electroluminescence display devices, plasma displays, or surface light source devices used in these display devices. It can be used as a light control device that enlarges the angle. Or it can utilize for various illuminating devices, such as an illuminating device which can adjust the area | region which light irradiates.
　１１，１１７，１２１，１２４，１２６，１２８，１３２，１３５，１４３，１４９，１５５，１５７，１８１…面光源装置、１２，１２ａ，１３３，１３６，１５０，１５８，２１１，２５１，２６１，２７１，２８１，２１０１、２１２１，２１３１，２１４１，２１５１，２１６１，２１７１，２１９１，２２０１…光源部、１３，１１８，１２２，１８２，２１２，２５２，２６２，２７２，２８２，２８４，２１４２，２１５２，２１６２，２１７２…導光体、１４…プリズムシート（方向変更用部材）、１７…第１のＬＥＤ（第１の発光素子）、１８…シリンドリカルレンズ（凸レンズ）、１９…凹面ミラー（角度分布変換部材）、１１３，１１３ａ，１３７，１４５，１５１，１５９…高指向性用光源部（第１の光源部）、１１４，１１４ａ，１３８，１５２，１６０…広角用光源部（第２の光源部）、１１５…第２のＬＥＤ（第２の発光素子）、１１９…プリズム構造体、１３９…楔形導光棒（角度分布変換部材）、１４６…導光棒（角度分布変換部材）、１５３…光散乱部材（角度分布変換部材）、１６１…平行化レンズ（角度分布変換部材）、１６５…液晶表示装置（表示装置）、１６６，２１８４…バックライト（面光源装置）、１６８…液晶パネル、１７５，１７６…電気スタンド（照明装置）、１７７，２１９０…シーリングライト（照明装置）、２１０，２５０，２６０，２７０，２８０，２１４０，２１５０，２１６０，２１７０…調光装置、２１３…散乱液晶セル、２１４，２６４，２７３，２９２，２１１２，２１３３，２１４３，２１５３，２１６３…反射ミラー、２１５，２６５，２７４，２９１，２１１１，２１３２，２１４４，２１５４，２１６５，２１７４…レンズ、２２１…高分子分散液晶、２２２，２２３…透明導電基板、２２４，２２６…透明基板、２２５，２２７…透明導電膜、２３１，２４１…液晶、２３２，２４３…ランダムポリマー、２４３…液晶ポリマー、２５３…液晶レンズ、２５４…第一透明基板、２５５…第二透明基板、２５６…第一透明電極、２５７…第二透明電極、２５８…絶縁性スペーサ、２５９…液晶層、２６３…散乱体、２７５…ゲル、２７６…散乱パターン、２７７，２７８…反射板、２８３，２１６６…プリズム、２８５，２９３，２１６３…散乱液晶セル、２１１３…突起、２１７３…エレクトロクロミックミラー、２１７５…反射手段、２１８０…表示装置、２１８１…液晶セル、２１８２，２１８３…偏光板、２１９２…吊下線、２１９３…電源コード、２２００…照明スタンド、２２０２…スタンド、２２０３…メインスイッチ、２２０４…電源コード。 11, 117, 121, 124, 126, 128, 132, 135, 143, 149, 155, 157, 181... Surface light source device, 12, 12a, 133, 136, 150, 158, 211, 251, 261, 271, 281, 2101, 2121, 2131, 2141, 2151, 2161, 2171, 2191, 2201... ... light guide, 14 ... prism sheet (direction changing member), 17 ... first LED (first light emitting element), 18 ... cylindrical lens (convex lens), 19 ... concave mirror (angle distribution converting member), 113 , 113a, 137, 145, 151, 159... High directivity light source section (first light source section), 14, 114a, 138, 152, 160 ... Wide-angle light source (second light source), 115 ... Second LED (second light-emitting element), 119 ... Prism structure, 139 ... Wedge-shaped light guide rod (angle) (Distribution conversion member), 146... Light guide rod (angle distribution conversion member), 153... Light scattering member (angle distribution conversion member), 161 .. collimating lens (angle distribution conversion member), 165... Liquid crystal display device (display device) 166, 2184 ... Backlight (surface light source device), 168 ... Liquid crystal panel, 175, 176 ... Desk lamp (illumination device), 177, 2190 ... Ceiling light (illumination device), 210, 250, 260, 270, 280, 2140, 2150, 2160, 2170 ... light control device, 213 ... scattering liquid crystal cell, 214, 264, 273, 292, 2112, 2133, 2143, 2153 2163: Reflection mirror, 215, 265, 274, 291, 2111, 1322, 2144, 2154, 2165, 2174 ... Lens, 221 ... Polymer dispersed liquid crystal, 222, 223 ... Transparent conductive substrate, 224, 226 ... Transparent substrate, 225 , 227 ... transparent conductive film, 231,241 ... liquid crystal, 232,243 ... random polymer, 243 ... liquid crystal polymer, 253 ... liquid crystal lens, 254 ... first transparent substrate, 255 ... second transparent substrate, 256 ... first transparent electrode 257 ... second transparent electrode, 258 ... insulating spacer, 259 ... liquid crystal layer, 263 ... scatterer, 275 ... gel, 276 ... scattering pattern, 277,278 ... reflecting plate, 283,2166 ... prism, 285,293, 2163 ... scattering liquid crystal cell, 2113 ... projection, 2173 ... electrochromic mirror, 2175 ... anti Projection means, 2180 ... display device, 2181 ... liquid crystal cell, 2182, 2183 ... polarizing plate, 2192 ... hanging line, 2193 ... power cord, 2200 ... lighting stand, 2202 ... stand, 2203 ... main switch, 2204 ... power cord.

Claims (28)

  1. 　第１の発光素子を有し、前記第１の発光素子からの光を射出する第１の光源部と、
    　第２の発光素子を有し、前記第２の発光素子からの光を、前記第１の光源部から射出される光の角度分布よりも広い角度分布を有する光として射出する第２の光源部と、
    　前記第１の光源部から射出された光および前記第２の光源部から射出された光を端面から入射させ、主面から射出させる導光体と、を備え、
    　前記第１の光源部と前記第２の光源部とは、前記導光体の複数の端面のうちの一つの端面に設けられ、点灯および消灯を各々独立して制御可能とされる面光源装置。     A first light source unit having a first light emitting element and emitting light from the first light emitting element;
    A second light source unit having a second light emitting element and emitting light from the second light emitting element as light having an angular distribution wider than the angular distribution of light emitted from the first light source unit When,
    A light guide that makes the light emitted from the first light source unit and the light emitted from the second light source unit incident from an end surface, and emits the light from the main surface,
    The first light source unit and the second light source unit are provided on one end surface of the plurality of end surfaces of the light guide, and can be independently controlled to be turned on and off. .
  2. 　前記第１の光源部および前記第２の光源部のいずれか一方が、前記第１の光源部から射出される光の角度分布と前記第２の光源部から射出される光の角度分布とを異ならせるための角度分布変換部材を備える請求項１に記載の面光源装置。 Either one of the first light source unit and the second light source unit calculates an angular distribution of light emitted from the first light source unit and an angular distribution of light emitted from the second light source unit. The surface light source device according to claim 1, further comprising an angle distribution conversion member for making the difference.
  3. 　前記第１の光源部は、前記角度分布変換部材として、前記第１の発光素子から射出された光を反射する凹面ミラーを備え、
    　前記凹面ミラーは、前記導光体の主面に平行な平面で切断したときの断面形状が、焦点を有する曲線形状を少なくとも一部に有し、
    　前記第１の発光素子は、前記第１の発光素子の発光面上に前記焦点が位置するように配置され、
    　前記第１の発光素子からの光が、前記凹面ミラーで反射して前記導光体に入射する請求項２に記載の面光源装置。     The first light source unit includes a concave mirror that reflects light emitted from the first light emitting element as the angle distribution conversion member,
    The concave mirror has, at least in part, a curved shape in which a cross-sectional shape when cut along a plane parallel to the main surface of the light guide has a focal point,
    The first light emitting element is disposed so that the focal point is located on a light emitting surface of the first light emitting element,
    The surface light source device according to claim 2, wherein light from the first light emitting element is reflected by the concave mirror and enters the light guide.
  4. 　前記第２の発光素子は、前記第１の光源部から射出される光の角度分布よりも広い角度分布を有する光を射出し、
    　前記第２の発光素子から射出された光が、前記凹面ミラーを介することなく前記導光体に入射する請求項３に記載の面光源装置。     The second light emitting element emits light having an angular distribution wider than the angular distribution of light emitted from the first light source unit,
    The surface light source device according to claim 3, wherein light emitted from the second light emitting element enters the light guide without passing through the concave mirror.
  5. 　前記第１の発光素子と前記第２の発光素子とは、互いの発光面と反対側の面同士が対向するように配置される請求項４に記載の面光源装置。 The surface light source device according to claim 4, wherein the first light emitting element and the second light emitting element are arranged so that surfaces opposite to each other's light emitting surface face each other.
  6. 　前記第１の光源部は、前記導光体の一つの端面に沿って配列された複数の前記発光素子および複数の前記凹面ミラーを備え、
    　前記第２の発光素子は、隣り合う凹面ミラー同士の境界に沿って配置される請求項４に記載の面光源装置。     The first light source unit includes a plurality of the light emitting elements and a plurality of concave mirrors arranged along one end surface of the light guide,
    The surface light source device according to claim 4, wherein the second light emitting element is disposed along a boundary between adjacent concave mirrors.
  7. 　前記凹面ミラーは、前記導光体の主面に垂直な平面で切断したときの断面形状が直線形状であって、前記導光体の主面に垂直な方向には曲率を持たず、
    　前記第１の発光素子は、前記導光体の主面に垂直な方向に沿って配置され、
    　前記第２の発光素子は、前記導光体の主面に平行な方向に沿って配置される請求項４に記載の面光源装置。     The concave mirror has a linear shape when cut in a plane perpendicular to the main surface of the light guide, and has no curvature in the direction perpendicular to the main surface of the light guide.
    The first light emitting element is disposed along a direction perpendicular to a main surface of the light guide,
    The surface light source device according to claim 4, wherein the second light emitting element is disposed along a direction parallel to a main surface of the light guide.
  8. 　前記第１の光源部が、前記凹面ミラーの窪みに配置された凸レンズを備え、
    　前記凸レンズの焦点の位置が前記凹面ミラーの焦点の位置と略一致している請求項３ないし７のいずれか一項に記載の面光源装置。     The first light source unit includes a convex lens disposed in a recess of the concave mirror;
    The surface light source device according to claim 3, wherein a focal position of the convex lens substantially coincides with a focal position of the concave mirror.
  9. 　前記凹面ミラーが、前記凸レンズの凸面に形成された金属膜もしくは誘電体多層膜で構成されている請求項８に記載の面光源装置。 9. The surface light source device according to claim 8, wherein the concave mirror is made of a metal film or a dielectric multilayer film formed on a convex surface of the convex lens.
  10. 　前記第１の光源部は、前記角度分布変換部材として、前記第１の発光素子から射出された光を反射する反射面を有する反射素子を備え、
    　前記反射素子は、前記導光体の前記一つの端面に対して一定の角度で傾斜した前記反射面と、前記導光体の前記一つの端面に対向する光射出面と、を有し、
    　前記第１の発光素子は、前記反射素子の一つの端面に配置されるとともに、前記第１の発光素子からの光が、前記反射面で反射して前記導光体に入射する請求項２に記載の面光源装置。     The first light source unit includes a reflection element having a reflection surface that reflects light emitted from the first light emitting element as the angle distribution conversion member,
    The reflective element includes the reflective surface inclined at a constant angle with respect to the one end surface of the light guide, and a light exit surface facing the one end surface of the light guide.
    The first light emitting element is disposed on one end face of the reflecting element, and light from the first light emitting element is reflected by the reflecting surface and enters the light guide. The surface light source device described.
  11. 　前記第２の発光素子は、前記第１の光源部から射出される光の角度分布よりも広い角度分布を有する光を射出し、
    　前記第２の発光素子から射出された光が、前記反射素子を介することなく前記導光体に入射する請求項１０に記載の面光源装置。     The second light emitting element emits light having an angular distribution wider than the angular distribution of light emitted from the first light source unit,
    The surface light source device according to claim 10, wherein light emitted from the second light emitting element enters the light guide without passing through the reflective element.
  12. 　前記反射素子が、前記導光体の前記一つの端面に対して複数個設けられる請求項１０または１１に記載の面光源装置。 The surface light source device according to claim 10 or 11, wherein a plurality of the reflective elements are provided for the one end face of the light guide.
  13. 　前記反射素子は、前記第１の発光素子が配置された端面に近い側から遠い側に向けて厚みが薄くなる楔形状を有し、前記光射出面と対向する端面全体が前記反射面である請求項１０ないし１２のいずれか一項に記載の面光源装置。 The reflective element has a wedge shape whose thickness decreases toward a side farther from a side closer to the end face on which the first light emitting element is disposed, and the entire end face facing the light emitting face is the reflective face. The surface light source device according to claim 10.
  14. 　前記反射素子は、前記光射出面と対向する面に複数のプリズム構造体を有し、前記プリズム構造体の一つの傾斜面が前記反射面である請求項１０ないし１２のいずれか一項に記載の面光源装置。 The said reflective element has a some prism structure in the surface facing the said light-projection surface, and one inclined surface of the said prism structure is the said reflective surface. Surface light source device.
  15. 　前記第２の光源部は、前記角度分布変換部材として、前記第２の発光素子から射出された光を散乱させる光散乱部材を備え、
    　前記第２の発光素子から射出された光が、前記光散乱部材を介して前記導光体に入射する請求項２に記載の面光源装置。     The second light source unit includes a light scattering member that scatters light emitted from the second light emitting element as the angle distribution conversion member,
    The surface light source device according to claim 2, wherein light emitted from the second light emitting element enters the light guide via the light scattering member.
  16. 　前記第１の光源部は、前記角度分布変換部材として、前記第１の発光素子から射出された光を略平行化するレンズを備え、
    　前記第１の発光素子から射出された光が、前記レンズを介して前記導光体に入射する請求項２に記載の面光源装置。     The first light source unit includes a lens that substantially parallelizes the light emitted from the first light emitting element as the angle distribution conversion member,
    The surface light source device according to claim 2, wherein light emitted from the first light emitting element is incident on the light guide through the lens.
  17. 　光源部と、
    　前記光源部を端部に持つ導光体と、
    　前記光源部と前記導光体との間または前記光源部における前記導光体の端部とは反対側に配設された配光変換素子と、を備え、
    　前記配光変換素子の配光特性が可変である調光装置。     A light source unit;
    A light guide having the light source portion at an end;
    A light distribution conversion element disposed between the light source section and the light guide body or on the opposite side of the light source section from the end of the light guide body,
    A light control device in which a light distribution characteristic of the light distribution conversion element is variable.
  18. 　前記配光変換素子は、前記光源部の前記導光体の一端面と対向する面とは反対の面側に設けられ、前記光源部からの光を反射する反射面を有する反射ミラーを備えたパラボラミラー形状のレンズである請求項１７に記載の調光装置。 The light distribution conversion element includes a reflection mirror that is provided on a surface opposite to a surface facing the one end surface of the light guide of the light source unit and has a reflection surface that reflects light from the light source unit. The light control device according to claim 17, wherein the light control device is a parabolic mirror-shaped lens.
  19. 　前記反射ミラーは、誘電体ミラーからなる請求項１８に記載の調光装置。 The light control device according to claim 18, wherein the reflection mirror is a dielectric mirror.
  20. 　前記反射ミラーの反射面に、散乱液晶セルが設けられる請求項１８または１９に記載の調光装置。 The light control device according to claim 18 or 19, wherein a scattering liquid crystal cell is provided on a reflection surface of the reflection mirror.
  21. 　前記レンズには、微小電子機械システム制御により、前記光源部側に出し入れ可能な複数の突起が設けられる請求項１８～２０のいずれか１項に記載の調光装置。 The light control device according to any one of claims 18 to 20, wherein the lens is provided with a plurality of protrusions that can be taken in and out of the light source unit by a micro electro mechanical system control.
  22. 　前記反射ミラーは、エレクトロクロミックミラーからなり、前記エレクトロクロミックミラーの前記光源部と対向する面とは反対の面側に、前記エレクトロクロミックミラーを透過した光を反射する反射手段が設けられる請求項１８に記載の調光装置。 The reflection mirror is composed of an electrochromic mirror, and reflection means for reflecting light transmitted through the electrochromic mirror is provided on a surface of the electrochromic mirror opposite to a surface facing the light source unit. The light control apparatus as described in.
  23. 　前記配光変換素子は、前記光源部と前記導光体の一端面との間に設けられる請求項１７に記載の調光装置。 The light control device according to claim 17, wherein the light distribution conversion element is provided between the light source unit and one end surface of the light guide.
  24. 　前記配光変換素子は、散乱液晶セルである請求項２３に記載の調光装置。 The light control device according to claim 23, wherein the light distribution conversion element is a scattering liquid crystal cell.
  25. 　前記配光変換素子は、液晶レンズである請求項２３に記載の調光装置。 The light control device according to claim 23, wherein the light distribution conversion element is a liquid crystal lens.
  26. 前記配光変換素子は、前記光源部と前記導光体の一端面との間に挿抜可能な散乱体である請求項２３に記載の調光装置。 24. The light control device according to claim 23, wherein the light distribution conversion element is a scatterer that can be inserted and removed between the light source unit and one end surface of the light guide.
  27. 　前記配光変換素子は、前記導光体の一端面に対向して配設された入光部と、前記入光部と前記一端面とを光学接着が可能なゲルと、前記一端面に設けられた散乱パターンと、前記ゲルと前記一端面との境界部を、前記導光体の厚さ方向から挟持する一対の反射板と、を備えてなる請求項２３に記載の調光装置。 The light distribution conversion element is provided on the one end surface, a light incident portion disposed opposite to one end surface of the light guide, a gel capable of optically bonding the light incident portion and the one end surface, and 24. The light control device according to claim 23, further comprising: a scattering pattern formed, and a pair of reflectors that sandwich a boundary between the gel and the one end face from a thickness direction of the light guide.
  28. 　前記配光変換素子は、楔形状の導光体と、前記導光体に対向し、光の入射面が鋸刃形状をなすプリズムとからなる請求項２３に記載の調光装置。 The light control device according to claim 23, wherein the light distribution conversion element includes a wedge-shaped light guide and a prism facing the light guide and having a light incident surface having a saw blade shape.
PCT/JP2012/081373 2011-12-05 2012-12-04 Surface light source device, light control device and display device using same, and illumination device WO2013084880A1 (en)

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JP2011266172A JP2015038811A (en) 2011-12-05 2011-12-05 Surface light source device, display device, and illumination device
JP2011-266172 2011-12-05
JP2011281478A JP2015038814A (en) 2011-12-22 2011-12-22 Dimmer, display device using the same, and lighting device using the same
JP2011-281478 2011-12-22

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