WO2011024641A1 - Optical element and light emitting device - Google Patents

Optical element and light emitting device Download PDF

Info

Publication number
WO2011024641A1
WO2011024641A1 PCT/JP2010/063535 JP2010063535W WO2011024641A1 WO 2011024641 A1 WO2011024641 A1 WO 2011024641A1 JP 2010063535 W JP2010063535 W JP 2010063535W WO 2011024641 A1 WO2011024641 A1 WO 2011024641A1
Authority
WO
WIPO (PCT)
Prior art keywords
light
emitting device
optical element
light emitting
meniscus lens
Prior art date
Application number
PCT/JP2010/063535
Other languages
French (fr)
Japanese (ja)
Inventor
恵一 望月
Original Assignee
日東光学株式会社
小池　康博
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
Application filed by 日東光学株式会社, 小池　康博 filed Critical 日東光学株式会社
Publication of WO2011024641A1 publication Critical patent/WO2011024641A1/en

Links

Images

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F21—LIGHTING
    • F21V—FUNCTIONAL FEATURES OR DETAILS OF LIGHTING DEVICES OR SYSTEMS THEREOF; STRUCTURAL COMBINATIONS OF LIGHTING DEVICES WITH OTHER ARTICLES, NOT OTHERWISE PROVIDED FOR
    • F21V5/00—Refractors for light sources
    • F21V5/04—Refractors for light sources of lens shape
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F21—LIGHTING
    • F21V—FUNCTIONAL FEATURES OR DETAILS OF LIGHTING DEVICES OR SYSTEMS THEREOF; STRUCTURAL COMBINATIONS OF LIGHTING DEVICES WITH OTHER ARTICLES, NOT OTHERWISE PROVIDED FOR
    • F21V7/00—Reflectors for light sources
    • F21V7/0091—Reflectors for light sources using total internal reflection
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B19/00—Condensers, e.g. light collectors or similar non-imaging optics
    • G02B19/0004—Condensers, e.g. light collectors or similar non-imaging optics characterised by the optical means employed
    • G02B19/0028—Condensers, e.g. light collectors or similar non-imaging optics characterised by the optical means employed refractive and reflective surfaces, e.g. non-imaging catadioptric systems
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B19/00—Condensers, e.g. light collectors or similar non-imaging optics
    • G02B19/0033—Condensers, e.g. light collectors or similar non-imaging optics characterised by the use
    • G02B19/0047—Condensers, e.g. light collectors or similar non-imaging optics characterised by the use for use with a light source
    • G02B19/0061—Condensers, e.g. light collectors or similar non-imaging optics characterised by the use for use with a light source the light source comprising a LED
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B5/00—Optical elements other than lenses
    • G02B5/02—Diffusing elements; Afocal elements
    • G02B5/0205—Diffusing elements; Afocal elements characterised by the diffusing properties
    • G02B5/0236—Diffusing elements; Afocal elements characterised by the diffusing properties the diffusion taking place within the volume of the element
    • G02B5/0242—Diffusing elements; Afocal elements characterised by the diffusing properties the diffusion taking place within the volume of the element by means of dispersed particles
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B5/00—Optical elements other than lenses
    • G02B5/02—Diffusing elements; Afocal elements
    • G02B5/0273—Diffusing elements; Afocal elements characterized by the use
    • G02B5/0278—Diffusing elements; Afocal elements characterized by the use used in transmission
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F21—LIGHTING
    • F21Y—INDEXING SCHEME ASSOCIATED WITH SUBCLASSES F21K, F21L, F21S and F21V, RELATING TO THE FORM OR THE KIND OF THE LIGHT SOURCES OR OF THE COLOUR OF THE LIGHT EMITTED
    • F21Y2105/00—Planar light sources
    • F21Y2105/10—Planar light sources comprising a two-dimensional array of point-like light-generating elements
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F21—LIGHTING
    • F21Y—INDEXING SCHEME ASSOCIATED WITH SUBCLASSES F21K, F21L, F21S and F21V, RELATING TO THE FORM OR THE KIND OF THE LIGHT SOURCES OR OF THE COLOUR OF THE LIGHT EMITTED
    • F21Y2115/00—Light-generating elements of semiconductor light sources
    • F21Y2115/10—Light-emitting diodes [LED]
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B27/00—Optical systems or apparatus not provided for by any of the groups G02B1/00 - G02B26/00, G02B30/00
    • G02B27/0018—Optical systems or apparatus not provided for by any of the groups G02B1/00 - G02B26/00, G02B30/00 with means for preventing ghost images
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L33/00—Semiconductor devices with at least one potential-jump barrier or surface barrier specially adapted for light emission; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
    • H01L33/48—Semiconductor devices with at least one potential-jump barrier or surface barrier specially adapted for light emission; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof characterised by the semiconductor body packages
    • H01L33/58—Optical field-shaping elements

Definitions

  • the present invention relates to an optical element and a light emitting device.
  • LED lighting devices have been put to practical use as an alternative to incandescent bulbs and fluorescent lamps due to the high power and high efficiency of LEDs (Light Emitting Diodes).
  • LEDs Light Emitting Diodes
  • LEDs are smaller in size and have a higher luminous flux density.
  • incandescent bulbs and fluorescent lamps emit light in all directions, whereas LEDs have a feature that the directivity of light rays is easily increased.
  • power LEDs of 3W or 10W have been put into practical use.
  • Patent Document 1 proposes an LED light bulb including a diffusion sheet on the outer surface of a light-transmitting globe. This LED bulb is supposed to have a substantially uniform luminance.
  • the LED light bulb proposed in Patent Document 1 cannot adjust the light distribution angle depending on its design. For this reason, when a high-power LED is used, the glare is large.
  • the present invention has been made under such a background, and an object thereof is to provide an optical element and a light-emitting device capable of reducing glare.
  • the optical element of the present invention is solid inside, and in an optical element that guides light incident from one surface and emits light from the other surface, one surface is concave, A meniscus lens having the other surface as a convex surface was formed, and the meniscus lens was formed of a light diffuser that diffuses light.
  • the other surface side has a spherical shape, and the edge of the meniscus lens serving as a boundary portion between the one surface and the other surface is an annular surface protruding to the opposite side of the spherical surface.
  • one surface has a grain shape that scatters light.
  • a light-emitting device of the present invention includes a light-emitting member and a light-emitting member that is solid inside and has an optical element that emits light emitted from the light-emitting member and is emitted from one surface.
  • the optical element is a meniscus lens having one surface as a concave surface and the other surface as a convex surface, and the meniscus lens is formed of a light diffuser that diffuses light.
  • the edge of the meniscus lens serving as a boundary portion between one surface and the other surface totally reflects the light entering from one surface.
  • the optical element has a holder that supports the optical element from one side, and the holder has a reflection surface that reflects light toward the optical element.
  • the incident angle at which the light is incident on the other surface is ⁇ , and the total reflection criticality of the other surface
  • the incident angle ⁇ in the range of ( ⁇ c ⁇ 1.7)> ⁇ > ( ⁇ c ⁇ 0.9) is preferably 20% or more.
  • FIG. 1 It is a figure which shows the optical path of the light radiate
  • FIG. It is a figure which shows the optical path of the light radiate
  • FIG. 1 It is a figure which shows the light emission state from the upper surface of the light-emitting device shown in FIG. It is a figure which shows the light emission state from the side surface of the light-emitting device shown in FIG. It is a longitudinal cross-sectional schematic diagram of the light-emitting device which concerns on the 4th Embodiment of this invention. It is a top view of the LED member of the light-emitting device shown in FIG. It is a figure which shows the light emission state from the upper surface of the light-emitting device shown in FIG. It is a figure which shows the light emission state from the side surface of the light-emitting device shown in FIG. It is a figure which shows the light emission state from the upper surface of the light-emitting device of the comparative example 2. It is a figure which shows the light emission state from the side surface of the light-emitting device of the comparative example 2. FIG.
  • FIG. 1 is a schematic vertical cross-sectional view of the light-emitting device 1.
  • the light-emitting device 1 includes an LED member 3 in which a chip-type LED serving as a light-emitting member is arranged in the center of a circular plate, a light guide 2 that guides light emitted from the LED member 3 and has a solid interior.
  • the holder 4 that holds the light guide 2 is provided.
  • the light guide 2 has a concave surface 11 that has a triangular pyramid shape on which light emitted from the LED member 3 is incident. This concave surface 11 becomes one surface.
  • the light guide 2 has a dome-shaped emission surface 12 (the other surface) that emits light emitted from the LED member 3 on the side opposite to the one surface. That is, the light guide 2 is a meniscus lens having a smooth concave surface 11 and a spherical emission surface 12. Furthermore, the light guide 2 has an edge 13 that surrounds the periphery of the concave surface 11 in the shape of a circular truncated cone in order to connect the concave surface 11 and the emission surface 12. That is, the light guide 2 is light emitted from the LED member 3 and guided into the light guide 2, and is lighted at a large angle (for example, 60 to 80 degrees) with respect to the central axis M of the light guide 2.
  • a large angle for example, 60 to 80 degrees
  • edge 13 that is an annular surface that reflects light emitted from the member 3.
  • the surface of the edge 13 is a convex surface that slightly protrudes in the circumferential direction of the light guide 2. That is, the curved surface slightly protrudes toward the LED member 3 side.
  • the light guide 2 is a resin molded body made of, for example, transparent polymethyl methacrylate (hereinafter abbreviated as “PMMA”).
  • PMMA transparent polymethyl methacrylate
  • translucent silicone particles that are light scattering particles having a particle diameter of 2 ⁇ m to 10 ⁇ m are dispersed. Thereby, the light guide 2 is a light diffuser.
  • This silicone particle is a light guide provided with a volumetric uniform scattering ability, and includes a large number of spherical particles as scattering fine particles. When light enters the light guide 2, the light is scattered by the scattering fine particles.
  • Mie scattering theory is the solution of Maxwell's electromagnetic equation for the case where spherical particles (scattering fine particles) having a refractive index different from that of the medium exist in a medium (matrix) having a uniform refractive index. .
  • the intensity distribution I ( ⁇ , ⁇ ) depending on the angle of the scattered light scattered by the scattering fine particles corresponding to the light scattering particles is expressed by the following equation (1).
  • ⁇ is a size parameter indicating the optical size of the scattering fine particles, and is an amount corresponding to the radius r of the spherical particles (scattering fine particles) normalized by the wavelength ⁇ of light in the matrix.
  • i 1 and i 2 in the formula (1) are represented by the formula (4).
  • a and b with the subscript ⁇ in the expressions (2) to (4) are expressed by the expression (5).
  • P (cos ⁇ ) with superscript 1 and subscript ⁇ is Legendre's polynomial
  • a and b with subscript ⁇ are first- and second-order Recati-Bessel functions ⁇ * and ⁇ * (where “*” Means the subscript ⁇ ) and its derivative.
  • m is the relative refractive index of the scattering fine particles based on the matrix
  • m nscatter / nmattrix.
  • FIG. 2 is a graph showing the intensity distribution I ( ⁇ , ⁇ ) by a single true spherical particle based on the above equations (1) to (5).
  • FIG. 2 shows the angular distribution I ( ⁇ , ⁇ ) of the scattered light intensity when there is a true spherical particle as a scattering fine particle at the position of the origin G and incident light is incident from below.
  • the distance from the origin G to each of the curves S1 to S3 is the scattered light intensity in each scattering angle direction.
  • Curve S1 shows the scattered light intensity when ⁇ is 1.7
  • curve S2 shows the scattered light intensity when ⁇ is 11.5
  • curve S3 shows the scattered light intensity when ⁇ is 69.2. Yes.
  • the scattered light intensity is shown on a logarithmic scale. For this reason, the portion that appears as a slight difference in intensity in FIG. 2 is actually a very large difference.
  • the larger the size parameter ⁇ (the larger the particle size of the true spherical particle when considered at a certain wavelength ⁇ ), the higher the directivity with respect to the upper side (front of the irradiation direction). It can be seen that light is highly scattered. Actually, the angle distribution I ( ⁇ , ⁇ ) of the scattered light intensity is controlled by using the radius r of the scatterer and the relative refractive index m of the medium and the scattered fine particles as parameters if the incident light wavelength ⁇ is fixed. can do. In addition, the light guide 2 has a large forward scattering.
  • I ( ⁇ ) in the equation (6) is the scattering intensity of the true spherical particle having the size parameter ⁇ represented by the equation (1). If light of intensity Io enters the light scattering light guide and passes through the distance y, then the intensity of the light is attenuated to I by scattering, and these relationships are expressed by the following equation (7).
  • ⁇ in the equation (7) is called turbidity and corresponds to the scattering coefficient of the medium, and is proportional to the number N of particles as in the following equation (8).
  • ⁇ s is a scattering cross section.
  • the degree of multiple scattering in the light scattering light guide can be controlled by changing the turbidity ⁇ .
  • the resin molded body holder 4 shown in FIG. 1 has an annular shape with the center cut out.
  • the annular inner peripheral surface is an inclined surface 21 that decreases in diameter as it goes from the upper side to the lower side in FIG.
  • the inclined surface 21 is a straight line in cross-sectional shape, and is a concave surface in the overall shape.
  • seat (illustration omitted) is affixed on this inclined surface 21 so that it may become a mirror surface. Therefore, the inclined surface 21 is a part of the concave mirror.
  • the inclined surface 21 may not be a concave mirror.
  • the light guide 2 is disposed so that the edge 13 faces the inclined surface 21 of the holder 4. Further, the edge 13 of the light guide 2 is held by the upper peripheral edge 22 of the holder 4.
  • the LED member 3 is fixed so as to face the cutout portion 23 cut out in a circular shape on the lower surface of the holder 4 in FIG. 1.
  • the position N1 that intersects the central axis M of the light guide 2 at the emission position of the LED member 3 is opposed to the conical apex of the concave surface 11.
  • the emission position N1 is also the central position of the LED member 3.
  • a gap 25 is formed between the edge 13 and the inclined surface 21 so that the gap becomes narrower from the concave surface 11 side toward the outer peripheral edge 22 on the upper side of the holder 4.
  • the optical path of the light emitted from the LED member 3 in the light emitting device 1 will be described. 3 to 6 show examples of the optical path.
  • the LED member 3 in the light emitting device 1, the LED member 3 is emitted not from the central position N ⁇ b> 1 but from the central emission position N ⁇ b> 1 in the outer peripheral direction, that is, from the emission position N ⁇ b> 2 toward the conical circumferential surface of the concave surface 11.
  • An optical path when light is irradiated to a specific region P of the concave surface 11 is shown.
  • the light has two optical paths: an optical path L1 that is transmitted from the region P to the light guide 2 and an optical path L2 of reflected light that is reflected by the region P.
  • the reason why the emission position N1 and the emission position N2 are assumed is that the light emission portion of the LED member 3 is not a point but a region having a predetermined area.
  • the optical path L1 is an optical path in which the light emitted from the LED member 3 hits a portion having the region P, enters the light guide 2 from the concave surface 11, and exits from the emission surface 12 to the outside.
  • the light emitted from the LED member 3 hits another part of the region P, is reflected by the region P of the concave surface 11, and then enters the inside of the light guide 2 from another region of the concave surface 11 to be emitted.
  • This is an optical path emitted from the surface 12 to the outside. It should be noted that the light is affected by the light scattering particles until the light enters the light guide 2 and is emitted to the outside from the light exit surface 12, and is scattered multiple times.
  • the optical paths L1 and L2 are both paths when no scattering occurs, and are high-probability paths even when subjected to multiple scattering.
  • FIG. 4 shows an optical path L3 of the light emitted from the emission position N2 of the LED member 3 to the lower region of the concave surface 11 with the light that has spread widely.
  • the light applied to the lower region enters the light guide 2 from the concave surface 11 and is then totally reflected by the edge 13.
  • the light taking such a path has a spread angle with respect to the central axis M exceeding 60 degrees. However, by changing the shape of the concave surface 11, it can be 45 degrees or more, or 65 degrees or more.
  • the light totally reflected by the edge 13 is further totally reflected at the exit surface 12.
  • the light is influenced by light scattering particles. Receiving and multiple scattering. For this reason, in the process of repeating total reflection on the emission surface 12, a part of the light is emitted from the emission surface 12 without being totally reflected.
  • the light paths L31, L32, and L33 of the emitted light are shown by broken lines in FIG. Note that not all of the light totally reflected by the edge 13 is totally reflected again by the emission surface 12. The role of the edge 13 is to apparently widen the emission range of the LED member 3.
  • the light that has spread further than the light shown in FIG. 4 is reflected by the mirror surface sheet of the inclined surface 21 and enters the specific region Q of the edge 13.
  • the optical path of the irradiated light is shown.
  • the light takes two optical paths L4 and L5.
  • the optical path L4 is an optical path through which the light emitted from the LED member 3 hits the region Q and enters the light guide 2 from the edge 13.
  • the light emitted from the LED member 3 hits the region Q, is reflected by the region Q of the edge 13, and then is reflected again by the mirror surface sheet of the inclined surface 21, and from the other region of the edge 13 of the light guide 2 It is an optical path that enters inside.
  • the light that has entered the light guide 2 repeats total reflection at the exit surface 12.
  • the light is influenced by the light scattering particles until the light enters the inside of the light guide 2 and repeats total reflection at the exit surface 12 and finally exits from the exit surface 12, so that multiple scattering occurs. To do. For this reason, in the process of repeating total reflection on the emission surface 12, a part of the light is emitted from the emission surface 12 without being totally reflected.
  • the light paths L41, L42, L51, and L52 of the emitted light are shown by broken lines in FIG.
  • the light that is reflected by the edge 13 or the holder 4 and is incident on the light guide 2 and has no light scattering particles is incident on the emission surface 12.
  • the incident angle ⁇ in the range of ( ⁇ c ⁇ 1.7)> ⁇ > ( ⁇ c ⁇ 0.9), where ⁇ is the incident angle of incidence and ⁇ c is the critical total reflection angle of the exit surface 12, 20% or more.
  • FIG. 6 shows an optical path L6 in the case where the light emitted from the LED member 3 is the emission position N4 on the side close to the outer periphery of the LED member 3.
  • the light takes an optical path L6.
  • the optical path L6 is first transmitted from the edge 13 to the inside of the light guide 2, then totally reflected by the concave surface 11, and then emitted from the emission surface 12 to the outside. Note that the light is affected by the light scattering particles until the light is transmitted to the inside of the light guide 2 and is emitted from the emission surface 12 to the outside.
  • a plurality of emission positions of the LED member 3 may be directed toward the concave surface 11.
  • FIG. 7 shows a light emission state from the upper surface of the light emitting device 1.
  • FIG. 8 shows a light emission state from the side surface of the light emitting device 1. 7 and 8, the light emission state is shown such that the emission luminance increases as the color approaches white, and the emission luminance decreases as the color approaches black.
  • FIG. 9 is a figure which shows the structural example of a comparison object, and has arrange
  • FIG. It is a longitudinal cross-sectional schematic diagram of the light-emitting device 93.
  • FIG. 10 shows a light emission state from the upper surface of the light emitting device 93.
  • FIG. 11 shows a light emission state from the side surface of the light emitting device 93. The light emission state is shown in the same manner as in FIGS.
  • the LED member 3 of the light emitting device 1 and the LED member 91 of the light emitting device 93 were the same, and the supplied power was also the same.
  • the emission positions N1, N2, etc. are the same as those of the light emitting device 1. That is, the emission range is the entire range of the LED members 3 and 91. This means that a square range with one side of the length in the left-right direction of the LED members 3 and 91 shown in the figure is the emission range.
  • FIGS. 10 and 11 are compared with FIGS. 10 and 11, it can be seen that the light emitting device 1 diffuses light to the entire light guide 2 and the glare can be reduced compared to the light emitting device 93. That is, in the light emitting device 93, as shown in FIG. 10, a high brightness portion, that is, a portion corresponding to the center of the emission range of the LED member 91 appears clearly in the central portion. As shown in FIG. 5, there is no high brightness portion in the center, and a ring-like high brightness portion appears around the center.
  • FIG. 12 is a schematic vertical cross-sectional view of the light-emitting device 31.
  • the light emitting device 31 has the same configuration as the light emitting device 1 except that the shape of the light guide 2 in the light emitting device 1 is different. Therefore, members other than the light guide 32 are denoted by the same reference numerals as those of the light emitting device 1 and description thereof is omitted.
  • the light guide 32 guides the light emitted from the LED member 3 and the inside is filled.
  • the light guide 32 has a concave surface 41 which is a cylindrical space so that the back side of the part where the light emitted from the LED member 3 enters is triangular pyramid, and the opening side continues from the triangular pyramid bottom surface. ing.
  • the concave surface 41 is one surface.
  • the light guide 32 has a light emitting surface 42 (the other surface) that emits light emitted from the LED member 3 on a side opposite to the one surface. That is, the light guide 32 is a meniscus lens having a concave surface 41 and an exit surface 42. Furthermore, the light guide 32 includes an annular portion 43 that surrounds the concave surface 41 and forms a right angle with the opening-side inner peripheral surface of the concave surface 41, and an annular portion 43 similar to the edge 13 in the light guide 2 of the light emitting device 1. Has an annular portion 44 which is an annular surface surrounding the circular truncated cone. These annular portions 43 and 44 are collectively referred to as an edge 45. The edge 45 reflects light emitted from the LED member 3 and guided into the light guide 2.
  • the optical path of the light emitted from the LED member 3 in the light emitting device 31 is substantially the same as that of the light emitting device 1. Further, the incident angle at which the light that is reflected by the edge 45 or the holder 4 and is incident on the light guide 32 and does not have light scattering particles when entering the light exit surface 42 is ⁇ , and the light exit surface 42.
  • the incident angle ⁇ in the range of ( ⁇ c ⁇ 1.7)> ⁇ > ( ⁇ c ⁇ 0.9) is 20% or more like the light emitting device 1 where the total reflection critical angle is ⁇ c. .
  • FIG. 13 shows a light emission state from the upper surface of the light emitting device 31.
  • FIG. 14 shows a light emission state from the side surface of the light emitting device 31.
  • the light emission state is shown in the same manner as in FIGS.
  • the LED member 3 of the light emitting device 31 and the LED device 3 of the light emitting device 1 were the same, and the supplied power was also the same. Comparing FIGS. 13 and 14 with FIGS. 10 and 11 for comparison, it is found that light is diffused in the entire light guide 32 and glare can be reduced in the light emitting device 31 rather than in the light emitting device 93. Recognize.
  • FIG. 15 is a schematic vertical cross-sectional view of the light-emitting device 51.
  • the light emitting device 51 has the same configuration as the light emitting device 31 except that the shape of the holder 4 in the light emitting device 31 is different and the thickness of the light guide 32 is slightly larger. Therefore, members other than the holder 53 are denoted by the same reference numerals as those of the light emitting device 31 and description thereof is omitted.
  • the height from the upper side to the lower side of the holder 53 in FIG. 15 is three times that of the holder 4.
  • the holder 53 has an annular shape with the center cut out.
  • the annular inner peripheral surface is a concave and curved inclined surface 61 that decreases in diameter as it goes from the upper side to the lower side in FIG.
  • a mirror surface sheet (not shown) is attached to the inclined surface 61 so as to be a mirror surface.
  • the inclined surface 61 is a concave mirror similar to the inclined surface 21 of the light emitting device 1. However, the inclined surface 61 may not be a concave mirror.
  • the light guide 32 is disposed so that the edge 45 faces the inclined surface 61 of the holder 53.
  • the edge 45 of the light guide 32 is held by the edge 62 of the holder 53.
  • the LED member 3 is fixed so as to face the cut-out portion 63 cut out in a circular shape on the lower surface of the holder 53 in FIG.
  • the emission position N1 of the LED member 3 is disposed so as to face the concave surface 41.
  • a gap 64 is formed between the edge 45 and the inclined surface 61 so that the gap becomes narrower from the concave surface 61 side toward the edge portion 62.
  • the light path of the light emitted from the LED member 3 in the light emitting device 51 is substantially the same as that of the light emitting device 1. Further, the incident angle at which the light that is reflected by the edge 45 or the holder 53 and is incident on the light guide 32 and does not include light scattering particles is incident on the exit surface 42 is ⁇ , and the exit surface 42
  • the incident angle ⁇ in the range of ( ⁇ c ⁇ 1.7)> ⁇ > ( ⁇ c ⁇ 0.9) is 20% or more like the light emitting device 1 where the total reflection critical angle is ⁇ c. .
  • FIG. 16 shows a light emission state from the upper surface of the light emitting device 51.
  • FIG. 17 shows a light emission state from the side surface of the light emitting device 51.
  • the light emission state is shown in the same manner as in FIGS.
  • the LED member 3 of the light emitting device 51 and the LED member 3 of the light emitting device 1 were the same, and the supplied power was also the same.
  • FIGS. 16 and 17 it is found that light is diffused in the entire light guide unit 32 and glare can be reduced in the light emitting device 51 than in the light emitting device 93. Recognize.
  • FIG. 18 is a schematic vertical cross-sectional view of the light emitting device 71.
  • the light emitting device 71 has the same configuration as that of the light emitting device 1 except that the light emitting device 1 has four light emission positions. That is, four LED 3A, 3B, 3C, 3D is arranged on one LED member 3. Therefore, the same reference numerals as those of the light emitting device 1 are used except for the emission center positions P1, P2, P3, P4 and the LEDs 3A to 3D which are the centers of the LED members 3A to 3D, and the description thereof is omitted.
  • the emission center positions P1 to P4 are positions facing the boundary position between the edge 13 and the concave surface 11.
  • FIG. 19 is a plan view of the LED member 3 of the light emitting device 71.
  • the square portions are LEDs 3A to 3D, and their center positions are emission center positions P1 to P4.
  • the optical path of light emitted from the LED member 3 in the light emitting device 71 is substantially the same as that of the light emitting device 1.
  • FIG. 20 shows a light emission state from the upper surface of the light emitting device 71.
  • FIG. 21 shows a light emission state from the side surface of the light emitting device 71. 20 and 21, the light emission state is shown such that the emission luminance increases as the color approaches white and the emission luminance decreases as the color approaches black.
  • FIG. 22 shows a comparative example 2 using the LED member 3 shown in FIGS. 18 and 19 in the light emitting device 93 of the comparative example, and shows a light emission state from the upper surface of the light emitting device.
  • FIG. 23 shows a light emission state from the side surface of the light emitting device of Comparative Example 2. The light emission state is shown in the same manner as in FIGS.
  • the same thing as the LED member 3 of the light-emitting device 71 was used, and the power supply was also made the same.
  • the light emitting device 71 diffuses light throughout the light guide 2 and the glare can be reduced compared to the light emitting device of Comparative Example 2. Recognize.
  • the light guides 2 and 32 according to the embodiment of the present invention are solid inside, and are meniscus lenses that guide the light incident from the concave surfaces 11 and 41 and emit the light from the output surfaces 12 and 42.
  • the lens was formed of a light diffuser containing light scattering particles that diffuse light. For this reason, the light distribution angle can be easily controlled by changing the shapes of the concave surfaces 11 and 41, and the glare can be reduced.
  • the light emitting devices 1, 31, 51, 71 can form an optical path that totally reflects part of the light on the emission surfaces 12, 42, while emitting part of the light.
  • the exit surfaces 12 and 42 side is spherical, and the edges 13 and 45 that serve as boundaries connecting the concave surfaces 11 and 41 and the exit surfaces 12 and 42 are annular convex surfaces. Therefore, the light that has entered the light guides 2 and 32 at a large angle with respect to the central axis M is easily totally reflected by the annular surfaces of the edges 13 and 45.
  • edges 13 and 45 totally reflect the light entering from the concave surfaces 11 and 41 and guide the light to the emission surfaces 12 and 42, the luminance is generated from outside the emission part of the LED member 3, and the luminance is uniform. And prevent glare more.
  • the holders 4 and 53 have a reflection surface that reflects light toward the light guides 2 and 32, even when there is light leaking in the direction of the holders 4 and 53, the light is guided. Returning to the bodies 2 and 32, the luminous efficiency of the light emitting devices 1, 31, 51, 71 is increased. In addition, since the light is totally reflected by the reflecting surfaces of the holders 4 and 53 and guided to the light guides 2 and 32 side, the brightness is generated from the outside of the emission part of the LED member 3, the brightness is made uniform, and the glare is further increased. Can be prevented.
  • the incident angle at which light is incident on the exit surfaces 12 and 42 is ⁇
  • the total reflection critical angle of the exit surfaces 12 and 42 is ⁇ c
  • the incident angle ⁇ in the range is 20% or more. Therefore, the probability of total reflection of light on the exit surfaces 12 and 42 is increased, and brightness can be generated from the entire exit surfaces 12 and 42 of the light guides 2 and 32. Light within this range can suppress the number of times of total reflection inside the light guides 2 and 32, and can maintain high emission efficiency.
  • the incident angle ⁇ in the range of ( ⁇ c ⁇ 1.7)> ⁇ > ( ⁇ c ⁇ 1.1) is 30% or more.
  • Light in this range has a high probability of being totally reflected and emitted to the side surfaces of the light guides 2 and 32 even when scattered, and the luminance is uniform even when viewed from the side surface.
  • the light guides 2 and 32 contain light scattering particles made of translucent silicone particles. Therefore, compared to the overall brightness of the light emitting device 93 (shown in FIGS. 10 and 11) when a conventional light diffusion sheet is used, the overall brightness of the light emitting devices 1, 31, 51, 71 (respectively illustrated). 7 and 8, FIG. 13 and FIG. 14, FIG. 16 and FIG. 17, FIG. 20 and FIG. This is because light diffusion by the light scattering particles has a low degree of light absorption.
  • the light guides 2 and 32 are solid bodies and are meniscus lenses that guide the light incident from the concave surfaces 11 and 41 and emit the light from the output surfaces 12 and 42.
  • the meniscus lens is formed of a light diffuser that contains light scattering particles that diffuse light.
  • the meniscus lens may be, for example, one in which silicone particles as a light diffuser are dispersed in a polycarbonate resin.
  • the light scattering particles are spherical and translucent silicone particles having a particle diameter of 2 ⁇ m to 9 ⁇ m.
  • various particles can be used regardless of their materials, shapes, particle diameters, etc., as long as they scatter multiple light in the light guide 2.
  • spherical and translucent silicone particles having a particle diameter of 2 ⁇ m to 9 ⁇ m, more preferably 5 ⁇ m to 9 ⁇ m, should be used. Is preferred.
  • the emission surfaces 12 and 42 are spherical (dome-shaped), and the edges 13 and 45 that connect the concave surfaces 11 and 41 and the emission surfaces 12 and 42 and protrude toward the LED member 3 are annular surfaces.
  • the exit surfaces 12 and 42 may have an elliptical sphere shape.
  • the edges 13 and 45 are not annular surfaces, and for example, a part of the annular shape may be interrupted. Further, the edges 13 and 45 protruding to the LED member 3 side may not be provided.
  • the concave surfaces 11 and 41 are smooth surfaces, they may have a grain shape that scatters light. By making the concave surfaces 11 and 41 have a textured shape, the diffusion and scattering of light in the light guides 2 and 32 is promoted.
  • edges 13 and 45 that are the boundary portions between the concave surfaces 11 and 41 and the emission surfaces 12 and 42 totally reflect the light that has entered the light guides 2 and 32 from the concave surfaces 11 and 41.
  • light may be transmitted through the edges 13 and 45 and reflected by the holders 4 and 53.
  • the light emitting devices 1, 31, 51, 71 have holders 4, 53 that support the light guides 2, 32 from the concave surfaces 11, 41 side, and the holders 4, 53 transmit light to the light guides 2, 2. It has a reflecting surface (mirror sheet affixed to the inclined surface 21) that reflects to the 32 side.
  • the light-emitting devices 1, 31, 51, 71 may omit the holders 4, 53 and their reflecting surfaces.
  • a prism may be formed on the surfaces of the edges 13 and 45 to reflect light.
  • the mirror surface may be formed by vapor deposition, polishing, or the like instead of attaching the mirror sheet to the inclined surfaces 21 and 61.
  • the light that is reflected by the edges 13 and 45 or the holders 4 and 53 and is incident on the light guides 2 and 32 without light scattering particles is generated.
  • the incident angle incident on the exit surfaces 12 and 42 is ⁇ and the total reflection critical angle of the exit surfaces 12 and 42 is ⁇ c
  • the incident angle ⁇ is 20% or more. However, the value may be less than 20%.
  • the emission positions A and B of the LED member 3 are directed toward the concave surface 11.
  • the emission center positions P1 to P4 of the LEDs 3A to 3D of the LED member 3 are directed to the boundary position between the concave surface 11 and the edge 13.
  • the emission center positions of the LEDs 3A to 3D may be directed toward the edge portions 13 and 45.
  • the emission position of the LED member 3 may be directed toward the concave surface 11 and the edges 13 and 45. In this case, a plurality of LEDs are used.
  • the light emitting member is not limited to the LED, but organic electroluminescence (Organic Other light-emitting members such as Electro-Luminescence (OEL, organic EL), inorganic electroluminescence (IEL, inorganic EL), and laser light can be used. Furthermore, although a chip type LED is used, an LED with a lens can be used.
  • Light-emitting device 2 32 Light guide (optical element, meniscus lens) 3 LED members (light emitting members) 4,53 Holder 11,41 Concave surface (one surface) 12, 42 Output surface (the other surface) 13,45 edge ⁇ Incident angle ⁇ c Total reflection critical angle

Abstract

Disclosed are an optical element and a light emitting device capable of reducing glare. A light guiding body (2) of which interior is solid is a meniscus lens that guides light entering a concave surface (11) and emits the light from a light emitting surface (12). The meniscus lens is formed of a light diffusing body containing light diffusing particles that diffuse light. A light emitting device (1) comprises the light guiding body (2), of which interior is solid, receiving light emitted from an LED member (3) using the concave surface (11) and emitting the light from the light emitting surface (12). The light guiding body (2) is a meniscus lens having the concave surface (11) serving as a concave and the light emitting surface (12) serving as a convex. This meniscus lens is formed of a light diffusing body that diffuses light.

Description

光学素子および発光装置Optical element and light emitting device
　本発明は、光学素子および発光装置に関する。 The present invention relates to an optical element and a light emitting device.
　近年、ＬＥＤ（Ｌｉｇｈｔ　Ｅｍｉｔｔｉｎｇ　Ｄｉｏｄｅ）のハイパワー化、高効率化により、白熱電球および蛍光灯の代替えとして、ＬＥＤ照明装置が実用化されてきている。白熱電球または蛍光灯に比べて、ＬＥＤは大きさが小さく、光束密度が高い。また、白熱電球および蛍光灯が全方位に発光するのに対して、ＬＥＤは光線の指向性を高くし易いという特徴を有する。また、最近では、３Ｗさらには１０ＷというパワーＬＥＤも実用化されている。 In recent years, LED lighting devices have been put to practical use as an alternative to incandescent bulbs and fluorescent lamps due to the high power and high efficiency of LEDs (Light Emitting Diodes). Compared with incandescent bulbs or fluorescent lamps, LEDs are smaller in size and have a higher luminous flux density. Further, incandescent bulbs and fluorescent lamps emit light in all directions, whereas LEDs have a feature that the directivity of light rays is easily increased. Recently, power LEDs of 3W or 10W have been put into practical use.
　このようなＬＥＤを光源とする電球として、特許文献１には、透光性のグローブの外表面に拡散シートを具備しているＬＥＤ電球が提案されている。このＬＥＤ電球は、その輝度をほぼ均一にできるものとされている。 As such a light bulb using an LED as a light source, Patent Document 1 proposes an LED light bulb including a diffusion sheet on the outer surface of a light-transmitting globe. This LED bulb is supposed to have a substantially uniform luminance.
特開２００８－９１１４０号公報JP 2008-91140 A
　しかしながら特許文献１に提案されているＬＥＤ電球は、その設計によって配光角を調整できない。そのため、ハイパワーのＬＥＤを用いた場合には、まぶしさ（グレア）の大きいものとなる。 However, the LED light bulb proposed in Patent Document 1 cannot adjust the light distribution angle depending on its design. For this reason, when a high-power LED is used, the glare is large.
　本発明は、このような背景の下に行われたものであって、グレアを低減できる光学素子および発光装置を提供することを目的とする。 The present invention has been made under such a background, and an object thereof is to provide an optical element and a light-emitting device capable of reducing glare.
　上記目的を達成するため、本発明の光学素子は、内部が充実体とされ、一方の面から入射された光を導光し他方の面から出射する光学素子において、一方の面を凹面とし、他方の面を凸面としたメニスカスレンズとし、メニスカスレンズを光を拡散する光拡散体で形成した。 In order to achieve the above object, the optical element of the present invention is solid inside, and in an optical element that guides light incident from one surface and emits light from the other surface, one surface is concave, A meniscus lens having the other surface as a convex surface was formed, and the meniscus lens was formed of a light diffuser that diffuses light.
　ここで、他方の面側が球形をなし、一方の面と他方の面との境界部となるメニスカスレンズのコバが、球形の面とは反対側に突出した環状の面となっていることが好ましい。 Here, it is preferable that the other surface side has a spherical shape, and the edge of the meniscus lens serving as a boundary portion between the one surface and the other surface is an annular surface protruding to the opposite side of the spherical surface. .
　また、一方の面は、光を散乱するシボ状になっていることが好ましい。 Further, it is preferable that one surface has a grain shape that scatters light.
　上記目的を達成するため、本発明の発光装置は、発光部材と、内部が充実体とされ、発光部材から発せられる光が一方の面から入射され他方の面から出射する光学素子とを有する発光装置において、光学素子は、一方の面を凹面とし、他方の面を凸面としたメニスカスレンズとされ、このメニスカスレンズは、光を拡散する光拡散体で形成されている。 In order to achieve the above object, a light-emitting device of the present invention includes a light-emitting member and a light-emitting member that is solid inside and has an optical element that emits light emitted from the light-emitting member and is emitted from one surface. In the apparatus, the optical element is a meniscus lens having one surface as a concave surface and the other surface as a convex surface, and the meniscus lens is formed of a light diffuser that diffuses light.
　ここで、一方の面と他方の面との境界部となるメニスカスレンズのコバが一方の面から進入してきた光を全反射することが好ましい。 Here, it is preferable that the edge of the meniscus lens serving as a boundary portion between one surface and the other surface totally reflects the light entering from one surface.
　また、光学素子を一方の面側から支える保持具を有し、保持具が、光を光学素子側に反射する反射面を有していることが好ましい。 Further, it is preferable that the optical element has a holder that supports the optical element from one side, and the holder has a reflection surface that reflects light toward the optical element.
　また、コバまたは保持具によって反射され、メニスカスレンズ内に入射した光であって光散乱体が無いとした場合の光が他方の面に入射する入射角をθとし、他方の面の全反射臨界角をθｃとしたとき、（θｃ×１．７）＞θ＞（θｃ×０．９）の範囲となる入射角θのものを２０％以上とすることが好ましい。 In addition, if the light is reflected by the edge or the holder and is incident on the meniscus lens and there is no light scatterer, the incident angle at which the light is incident on the other surface is θ, and the total reflection criticality of the other surface When the angle is θc, the incident angle θ in the range of (θc × 1.7)> θ> (θc × 0.9) is preferably 20% or more.
　本発明によれば、グレアを低減できる光学素子および発光装置を提供することができる。 According to the present invention, it is possible to provide an optical element and a light emitting device that can reduce glare.
本発明の第１の実施の形態に係る発光装置の縦断面概要図である。It is a longitudinal cross-sectional schematic diagram of the light-emitting device which concerns on the 1st Embodiment of this invention. 図１に示す導光体中の光散乱粒子となるシリコーン粒子の散乱原理を示す図で、単一真球粒子による散乱光強度の角度分布（Α、Θ）を示すグラフである。It is a figure which shows the scattering principle of the silicone particle | grains used as the light-scattering particle | grains in the light guide shown in FIG. 1, and is a graph which shows angle distribution (Α, Θ) of the scattered light intensity by a single true spherical particle. 図１に示す発光装置におけるＬＥＤ部材から出射された光の光路を示す図であり、凹面の特定の領域に照射される光の光路を示す図である。It is a figure which shows the optical path of the light radiate | emitted from the LED member in the light-emitting device shown in FIG. 1, and is a figure which shows the optical path of the light irradiated to the specific area | region of a concave surface. 図１に示す発光装置におけるＬＥＤ部材から出射された光の光路を示す図であり、ＬＥＤ部材から出射された光のうち、大きく広がった光が凹面の下部領域に照射された光の光路を示す図である。It is a figure which shows the optical path of the light radiate | emitted from the LED member in the light-emitting device shown in FIG. 1, and shows the optical path of the light by which the light which spread widely among the light radiate | emitted from the LED member was irradiated to the lower area | region of the concave surface. FIG. 図１に示す発光装置におけるＬＥＤ部材から出射された光の光路を示す図であり、ＬＥＤ部材から出射された光のうち、図４に示す光よりさらに大きく広がった光が傾斜面の鏡面シートに反射してコバの特定の領域に照射された光の光路を示す図である。It is a figure which shows the optical path of the light radiate | emitted from the LED member in the light-emitting device shown in FIG. 1, Out of the light radiate | emitted from the LED member, the light which spread more largely than the light shown in FIG. 4 is on the mirror surface sheet of an inclined surface. It is a figure which shows the optical path of the light which reflected and was irradiated to the specific area | region of the edge. 図１に示す発光装置においてＬＥＤから直接コバの特定の領域に向けて出射された光の光路を示す図である。It is a figure which shows the optical path of the light radiate | emitted toward the specific area | region of the edge directly from LED in the light-emitting device shown in FIG. 図１に示す発光装置の上面からの発光状態を示す図である。It is a figure which shows the light emission state from the upper surface of the light-emitting device shown in FIG. 図１に示す発光装置の側面からの発光状態を示す図である。It is a figure which shows the light emission state from the side surface of the light-emitting device shown in FIG. 比較例の構成を示す図で、ＬＥＤ部材の外表面に拡散シートをを配置した比較例の発光装置の縦断面概要図を示す図である。It is a figure which shows the structure of a comparative example, and is a figure which shows the longitudinal cross-sectional schematic diagram of the light-emitting device of the comparative example which has arrange | positioned the diffusion sheet to the outer surface of an LED member. 図９に示す比較例の発光装置の上面からの発光状態を示す図である。It is a figure which shows the light emission state from the upper surface of the light-emitting device of the comparative example shown in FIG. 図９に示す比較例の発光装置の側面からの発光状態を示す図である。It is a figure which shows the light emission state from the side surface of the light-emitting device of the comparative example shown in FIG. 本発明の第２の実施の形態に係る発光装置の縦断面概要図である。It is a longitudinal cross-sectional schematic diagram of the light-emitting device which concerns on the 2nd Embodiment of this invention. 図１２に示す発光装置の上面からの発光状態を示す図である。It is a figure which shows the light emission state from the upper surface of the light-emitting device shown in FIG. 図１２に示す発光装置の側面からの発光状態を示す図である。It is a figure which shows the light emission state from the side surface of the light-emitting device shown in FIG. 本発明の第３の実施の形態に係る発光装置の縦断面概要図である。It is a longitudinal cross-sectional schematic diagram of the light-emitting device which concerns on the 3rd Embodiment of this invention. 図１５に示す発光装置の上面からの発光状態を示す図である。It is a figure which shows the light emission state from the upper surface of the light-emitting device shown in FIG. 図１５に示す発光装置の側面からの発光状態を示す図である。It is a figure which shows the light emission state from the side surface of the light-emitting device shown in FIG. 本発明の第４の実施の形態に係る発光装置の縦断面概要図である。It is a longitudinal cross-sectional schematic diagram of the light-emitting device which concerns on the 4th Embodiment of this invention. 図１８に示す発光装置のＬＥＤ部材の平面図である。It is a top view of the LED member of the light-emitting device shown in FIG. 図１８に示す発光装置の上面からの発光状態を示す図である。It is a figure which shows the light emission state from the upper surface of the light-emitting device shown in FIG. 図１８に示す発光装置の側面からの発光状態を示す図である。It is a figure which shows the light emission state from the side surface of the light-emitting device shown in FIG. 比較例２の発光装置の上面からの発光状態を示す図である。It is a figure which shows the light emission state from the upper surface of the light-emitting device of the comparative example 2. 比較例２の発光装置の側面からの発光状態を示す図である。It is a figure which shows the light emission state from the side surface of the light-emitting device of the comparative example 2. FIG.
（本発明の第１の実施の形態に係る発光装置１について）
　本発明の第１の実施の形態に係る発光装置１および発光装置１に用いられる光学素子としての導光体２の構成について説明する。 (About the light emitting device 1 according to the first embodiment of the present invention)
The structure of the light guide 2 as an optical element used for the light-emitting device 1 and the light-emitting device 1 according to the first embodiment of the present invention will be described.
　図１は、発光装置１の縦断面概要図である。発光装置１は、発光部材となるチップ型のＬＥＤを円形板状の中央に配置したＬＥＤ部材３と、ＬＥＤ部材３から発せられる光を導光し内部が充実体とされる導光体２と、導光体２を保持する保持具４を有している。導光体２は、ＬＥＤ部材３から発せられる光が入射する三角錐状にえぐれた凹面１１を有している。この凹面１１が、一方の面となる。 FIG. 1 is a schematic vertical cross-sectional view of the light-emitting device 1. The light-emitting device 1 includes an LED member 3 in which a chip-type LED serving as a light-emitting member is arranged in the center of a circular plate, a light guide 2 that guides light emitted from the LED member 3 and has a solid interior. The holder 4 that holds the light guide 2 is provided. The light guide 2 has a concave surface 11 that has a triangular pyramid shape on which light emitted from the LED member 3 is incident. This concave surface 11 becomes one surface.
　そして、導光体２は、一方の面とは反対側に、球形をなしＬＥＤ部材３から発せられた光を出射するドーム形状の出射面１２（他方の面）を有している。すなわち、導光体２は、平滑な凹面１１と球形状の出射面１２を有するメニスカスレンズである。さらに、導光体２は、凹面１１と出射面１２とをつなぐために凹面１１の周囲を円錐台の周面状に取り囲むコバ１３を有している。すなわち、導光体２は、ＬＥＤ部材３から発せられ導光体２内に導光された光であって導光体２の中心軸Ｍに対して大きな角度（たとえば６０から８０度）でＬＥＤ部材３から出射される光を反射する環状の面であるコバ１３を有している。このコバ１３の面は、導光体２の周方向に若干突出する凸面となっている。すなわち、ＬＥＤ部材３側にわずかに突出する曲面となっている。 The light guide 2 has a dome-shaped emission surface 12 (the other surface) that emits light emitted from the LED member 3 on the side opposite to the one surface. That is, the light guide 2 is a meniscus lens having a smooth concave surface 11 and a spherical emission surface 12. Furthermore, the light guide 2 has an edge 13 that surrounds the periphery of the concave surface 11 in the shape of a circular truncated cone in order to connect the concave surface 11 and the emission surface 12. That is, the light guide 2 is light emitted from the LED member 3 and guided into the light guide 2, and is lighted at a large angle (for example, 60 to 80 degrees) with respect to the central axis M of the light guide 2. It has an edge 13 that is an annular surface that reflects light emitted from the member 3. The surface of the edge 13 is a convex surface that slightly protrudes in the circumferential direction of the light guide 2. That is, the curved surface slightly protrudes toward the LED member 3 side.
　また、導光体２は、たとえば透明のポリメチルメタクリレート（以下、「ＰＭＭＡ」と略記する。）からなる樹脂成形体である。そして、ＰＭＭＡには、粒子径が２μｍ～１０μｍの光散乱粒子となる透光性シリコーン粒子を分散させてある。これにより、導光体２は、光拡散体になっている。 The light guide 2 is a resin molded body made of, for example, transparent polymethyl methacrylate (hereinafter abbreviated as “PMMA”). In PMMA, translucent silicone particles that are light scattering particles having a particle diameter of 2 μm to 10 μm are dispersed. Thereby, the light guide 2 is a light diffuser.
　以下、導光体２のシリコーン粒子について説明する。このシリコーン粒子は、体積的に一様な散乱能が与えられた導光体であり、散乱微粒子としての球形粒子を多数含んでいる。導光体２の内部に光が入射すると、その光は散乱微粒子によって散乱することになる。 Hereinafter, the silicone particles of the light guide 2 will be described. This silicone particle is a light guide provided with a volumetric uniform scattering ability, and includes a large number of spherical particles as scattering fine particles. When light enters the light guide 2, the light is scattered by the scattering fine particles.
　ここで、シリコーン粒子の理論的な基礎を与えるＭｉｅ散乱理論について説明する。Ｍｉｅ散乱理論は、一様な屈折率を有する媒体（マトリックス）中に該媒体と異なる屈折率を有する球形粒子（散乱微粒子）が存在するケースについてマックスウェルの電磁方程式の解を求めたものである。光散乱粒子に相当する散乱微粒子によって散乱した散乱光の角度に依存した強度分布Ｉ（Α、Θ）は下記（１）式で表される。Αは、散乱微粒子の光学的大きさを示すサイズパラメータであり、マトリックス中での光の波長λで規格化された球形粒子（散乱微粒子）の半径ｒに相当する量である。角度Θは散乱角で、入射光の進行方向と同一方向をΘ＝１８０°にとる。 Here, the Mie scattering theory that gives the theoretical basis of silicone particles will be described. Mie scattering theory is the solution of Maxwell's electromagnetic equation for the case where spherical particles (scattering fine particles) having a refractive index different from that of the medium exist in a medium (matrix) having a uniform refractive index. . The intensity distribution I (Α, Θ) depending on the angle of the scattered light scattered by the scattering fine particles corresponding to the light scattering particles is expressed by the following equation (1). Α is a size parameter indicating the optical size of the scattering fine particles, and is an amount corresponding to the radius r of the spherical particles (scattering fine particles) normalized by the wavelength λ of light in the matrix. The angle Θ is a scattering angle, and the same direction as the traveling direction of incident light is Θ = 180 °.
　また、（１）式中のｉ１、ｉ２は（４）式で表される。そして、（２）～（４）式中の下添字ν付のａおよびｂは（５）式で表される。上添字１および下添字νを付したＰ（ｃｏｓΘ）は、Ｌｅｇｅｎｄｒｅの多項式、下添字ν付のａ、ｂは１次、２次のＲｅｃａｔｔｉ－Ｂｅｓｓｅｌ関数Ψ＊、ζ＊（ただし、「＊」は下添字νを意味する。）とその導関数とからなる。ｍはマトリックスを基準にした散乱微粒子の相対屈折率で、ｍ＝ｎｓｃａｔｔｅｒ／ｎｍａｔｒｉｘである。 Further, i 1 and i 2 in the formula (1) are represented by the formula (4). Then, a and b with the subscript ν in the expressions (2) to (4) are expressed by the expression (5). P (cos Θ) with superscript 1 and subscript ν is Legendre's polynomial, and a and b with subscript ν are first- and second-order Recati-Bessel functions Ψ * and ζ * (where “*” Means the subscript ν) and its derivative. m is the relative refractive index of the scattering fine particles based on the matrix, and m = nscatter / nmattrix.
Figure JPOXMLDOC01-appb-M000001
Figure JPOXMLDOC01-appb-M000001
　図２は、上記（１）～（５）式に基づいて、単一真球粒子による強度分布Ｉ（Α、Θ）を示すグラフである。この図２では、原点Ｇの位置に散乱微粒子としての真球粒子があり、下方から入射光が入射した場合の散乱光強度の角度分布Ｉ（Α、Θ）を示している。そして、原点Ｇから各曲線Ｓ１～Ｓ３までの距離が、それぞれの散乱角方向の散乱光強度である。曲線Ｓ１はΑが１．７であるときの散乱光強度、曲線Ｓ２はΑが１１．５であるときの散乱光強度、曲線Ｓ３はΑが６９．２であるときの散乱光強度を示している。なお、図２においては、散乱光強度を対数目盛で示している。このため、図２では僅かな強度差として見える部分が、実際には非常に大きな差となる。 FIG. 2 is a graph showing the intensity distribution I (Α, Θ) by a single true spherical particle based on the above equations (1) to (5). FIG. 2 shows the angular distribution I (Α, Θ) of the scattered light intensity when there is a true spherical particle as a scattering fine particle at the position of the origin G and incident light is incident from below. The distance from the origin G to each of the curves S1 to S3 is the scattered light intensity in each scattering angle direction. Curve S1 shows the scattered light intensity when Α is 1.7, curve S2 shows the scattered light intensity when Α is 11.5, and curve S3 shows the scattered light intensity when Α is 69.2. Yes. In FIG. 2, the scattered light intensity is shown on a logarithmic scale. For this reason, the portion that appears as a slight difference in intensity in FIG. 2 is actually a very large difference.
　この図２に示すように、サイズパラメータΑが大きくなればなるほど（ある波長λで考えた場合は真球粒子の粒径が大きくなればなるほど）、上方（照射方向の前方）に対して指向性高く光が散乱されていることがわかる。また、実際のところ、散乱光強度の角度分布Ｉ（Α、Θ）は、入射光波長λを固定すれば、散乱子の半径ｒと、媒体および散乱微粒子の相対屈折率ｍとをパラメータとして制御することができる。なお、導光体２は、前方散乱が大きいものとなっている。 As shown in FIG. 2, the larger the size parameter Α (the larger the particle size of the true spherical particle when considered at a certain wavelength λ), the higher the directivity with respect to the upper side (front of the irradiation direction). It can be seen that light is highly scattered. Actually, the angle distribution I (Α, Θ) of the scattered light intensity is controlled by using the radius r of the scatterer and the relative refractive index m of the medium and the scattered fine particles as parameters if the incident light wavelength λ is fixed. can do. In addition, the light guide 2 has a large forward scattering.
　このような、単一真球粒子がＮ個含まれる光散乱導光体に光を入射させると、光は真球粒子により散乱される。散乱光は光散乱導光体中を進み、他の真球粒子により再度散乱される。ある程度以上の体積濃度で粒子を添加した場合には、このような散乱が逐次的に複数回行われた後、光が光散乱導光体から出射する。このような散乱光がさらに散乱されるような現象を多重散乱現象と呼ぶ。このような多重散乱においては、透明ポリマーでの光線追跡法による解析は容易ではない。しかし、モンテカルロ法により光の挙動を追跡し、その特性を解析することはできる。それによると、入射光が無偏光の場合、散乱角の累積分布関数Ｆ（Θ）は下記の（６）式で表される。 When light is incident on such a light scattering light guide containing N single true spherical particles, the light is scattered by the true spherical particles. Scattered light travels through the light scattering light guide and is again scattered by other spherical particles. When particles are added at a volume concentration of a certain level or more, such scattering is sequentially performed a plurality of times, and then light is emitted from the light scattering light guide. A phenomenon in which such scattered light is further scattered is called a multiple scattering phenomenon. In such multiple scattering, analysis by a ray tracing method with a transparent polymer is not easy. However, the behavior of light can be traced by the Monte Carlo method and its characteristics can be analyzed. According to this, when the incident light is non-polarized light, the cumulative distribution function F (Θ) of the scattering angle is expressed by the following equation (6).
Figure JPOXMLDOC01-appb-M000002
Figure JPOXMLDOC01-appb-M000002
　ここで（６）式中のＩ（Θ）は、（１）式で表されるサイズパラメータΑの真球粒子の散乱強度である。強度Ｉｏの光が光散乱導光体に入射し、距離ｙを透過した後、光の強度が散乱によりＩに減衰したとすると、これらの関係は下記の（７）式で表される。 Here, I (Θ) in the equation (6) is the scattering intensity of the true spherical particle having the size parameter 表 represented by the equation (1). If light of intensity Io enters the light scattering light guide and passes through the distance y, then the intensity of the light is attenuated to I by scattering, and these relationships are expressed by the following equation (7).
Figure JPOXMLDOC01-appb-M000003
Figure JPOXMLDOC01-appb-M000003
　この（７）式中のτは濁度と呼ばれ、媒体の散乱係数に相当するものであり、下記の（８）式のように粒子数Ｎに比例する。なお、（８）式中、σｓは散乱断面積である。 Τ in the equation (7) is called turbidity and corresponds to the scattering coefficient of the medium, and is proportional to the number N of particles as in the following equation (8). In the equation (8), σ s is a scattering cross section.
Figure JPOXMLDOC01-appb-M000004
Figure JPOXMLDOC01-appb-M000004
　（７）式から長さＬの光散乱導光体を散乱せずに透過する確率Ｐｔ（Ｌ）は下記の（９）式で表される。 From the equation (7), the probability P t (L) of transmitting through the light-scattering light guide of length L without scattering is expressed by the following equation (9).
Figure JPOXMLDOC01-appb-M000005
Figure JPOXMLDOC01-appb-M000005
　反対に光路長Ｌまでに散乱される確率Ｐｓ（Ｌ）は下記の（１０）式で表される。
Figure JPOXMLDOC01-appb-M000006
 On the other hand, the probability P s (L) that is scattered up to the optical path length L is expressed by the following equation (10).
Figure JPOXMLDOC01-appb-M000006
　これらの式からわかるように、濁度τを変えることにより、光散乱導光体内での多重散乱の度合いを制御することができる。 As can be seen from these equations, the degree of multiple scattering in the light scattering light guide can be controlled by changing the turbidity τ.
　以上の関係式により、散乱微粒子のサイズパラメータΑと濁度τとの少なくとも１つをパラメータとして、光散乱導光体内での多重散乱を制御可能であり、出射面１２における出射光強度と散乱角も適正に設定可能である。 By the above relational expression, it is possible to control the multiple scattering in the light scattering light guide using at least one of the size parameter Α and the turbidity τ of the scattering fine particles as parameters, and the outgoing light intensity and the scattering angle on the outgoing surface 12. Can also be set appropriately.
　図１に示す樹脂成形体の保持具４は、中央がくり抜かれた円環状の形状をしている。その円環状の内周面は、図１における上側から下側に向かうに従い円環状の径を小さくする傾斜面２１となっている。この傾斜面２１は、断面形状で直線となり、全体形状では凹面とされている。そして、この傾斜面２１には、鏡面となるように鏡面シート（図示省略）が貼付されている。よって、傾斜面２１は、凹面鏡の一部となっている。なお、傾斜面２１は、曲面状の凹部の一部として形成しても良い。このように傾斜面２１は、凹面鏡の一部を形成する構成としているが、傾斜面２１は、凹面鏡としなくても良い。 The resin molded body holder 4 shown in FIG. 1 has an annular shape with the center cut out. The annular inner peripheral surface is an inclined surface 21 that decreases in diameter as it goes from the upper side to the lower side in FIG. The inclined surface 21 is a straight line in cross-sectional shape, and is a concave surface in the overall shape. And the mirror surface sheet | seat (illustration omitted) is affixed on this inclined surface 21 so that it may become a mirror surface. Therefore, the inclined surface 21 is a part of the concave mirror. In addition, you may form the inclined surface 21 as a part of curved-surface-shaped recessed part. Thus, although the inclined surface 21 is configured to form a part of the concave mirror, the inclined surface 21 may not be a concave mirror.
　導光体２は、コバ１３が保持具４の傾斜面２１に対向するように配置されている。また、導光体２のコバ１３は、保持具４の上側の外周の縁部２２にて保持されている。ＬＥＤ部材３は、図１における保持具４の下側面の円形にくり抜かれたくり抜き部２３に対向するように固定されている。その結果、ＬＥＤ部材３の出射位置で導光体２の中心軸Ｍと交差する位置Ｎ１は、凹面１１の円錐状の頂点に対向するようにされている。この出射位置Ｎ１は、ＬＥＤ部材３の中央位置でもある。また、コバ１３と傾斜面２１との間は、凹面１１側から保持具４の上側の外周の縁部２２に向かうに従って隙間の狭くなる間隙２５となっている。 The light guide 2 is disposed so that the edge 13 faces the inclined surface 21 of the holder 4. Further, the edge 13 of the light guide 2 is held by the upper peripheral edge 22 of the holder 4. The LED member 3 is fixed so as to face the cutout portion 23 cut out in a circular shape on the lower surface of the holder 4 in FIG. 1. As a result, the position N1 that intersects the central axis M of the light guide 2 at the emission position of the LED member 3 is opposed to the conical apex of the concave surface 11. The emission position N1 is also the central position of the LED member 3. Further, a gap 25 is formed between the edge 13 and the inclined surface 21 so that the gap becomes narrower from the concave surface 11 side toward the outer peripheral edge 22 on the upper side of the holder 4.
　発光装置１におけるＬＥＤ部材３から出射された光の光路について説明する。図３から図６に、その光路の各例を示している。図３は、発光装置１において、ＬＥＤ部材３の中央位置Ｎ１ではなく、中央の出射位置Ｎ１から外周方向にずれた位置、すなわち凹面１１の円錐状の周面に向かう出射位置Ｎ２から出射された光が凹面１１の特定の領域Ｐに照射された場合の光路を示している。その光は、領域Ｐから導光体２に透過される光路Ｌ１と、領域Ｐにて反射される反射光の光路Ｌ２の２つの光路である。出射位置Ｎ１と出射位置Ｎ２を想定するのは、ＬＥＤ部材３の光の出射部位が点ではなく所定の面積を有する領域となるためである。 The optical path of the light emitted from the LED member 3 in the light emitting device 1 will be described. 3 to 6 show examples of the optical path. In FIG. 3, in the light emitting device 1, the LED member 3 is emitted not from the central position N <b> 1 but from the central emission position N <b> 1 in the outer peripheral direction, that is, from the emission position N <b> 2 toward the conical circumferential surface of the concave surface 11. An optical path when light is irradiated to a specific region P of the concave surface 11 is shown. The light has two optical paths: an optical path L1 that is transmitted from the region P to the light guide 2 and an optical path L2 of reflected light that is reflected by the region P. The reason why the emission position N1 and the emission position N2 are assumed is that the light emission portion of the LED member 3 is not a point but a region having a predetermined area.
　光路Ｌ１は、ＬＥＤ部材３から出射された光が領域Ｐのある部分に当たり、凹面１１から導光体２の内部へと進入し、出射面１２から外部へ出射する光路である。光路Ｌ２は、ＬＥＤ部材３から出射された光が領域Ｐの他の部分に当たり、凹面１１の領域Ｐで反射し、その後凹面１１の別の領域から導光体２の内部へと進入し、出射面１２から外部へ出射する光路である。なお、光が導光体２の内部へと進入し出射面１２から外部へ出射するまでの間は、光は光散乱粒子の影響を受け、多重散乱する。光路Ｌ１，Ｌ２は、共に散乱が生じていないとしたときの経路であると共に多重散乱を受けた場合であっても確率が高い経路でもある。 The optical path L1 is an optical path in which the light emitted from the LED member 3 hits a portion having the region P, enters the light guide 2 from the concave surface 11, and exits from the emission surface 12 to the outside. In the optical path L2, the light emitted from the LED member 3 hits another part of the region P, is reflected by the region P of the concave surface 11, and then enters the inside of the light guide 2 from another region of the concave surface 11 to be emitted. This is an optical path emitted from the surface 12 to the outside. It should be noted that the light is affected by the light scattering particles until the light enters the light guide 2 and is emitted to the outside from the light exit surface 12, and is scattered multiple times. The optical paths L1 and L2 are both paths when no scattering occurs, and are high-probability paths even when subjected to multiple scattering.
　図４には、ＬＥＤ部材３の出射位置Ｎ２から出射された光のうち、大きく広がった光が凹面１１の下部領域に照射された光の光路Ｌ３を示している。この下部領域に照射された光は、凹面１１から導光体２の内部へと進入し、その後、コバ１３にて全反射する。このような経路を取る光は、中心軸Ｍに対する広がり角度が６０度を超えるものとなっている。しかし、凹面１１の形状を変えることによって４５度以上のものとしたり、６５度以上のものとしたりすることができる。コバ１３にて全反射した光は、さらに出射面１２にて全反射を繰り返す。このとき、光が導光体２の内部へと進入し出射面１２にて全反射を繰り返し、最後に導光体２の出射面から出射するまでの間は、光は光散乱粒子の影響を受け、多重散乱する。そのため、出射面１２にて全反射を繰り返す過程で、その光の一部は、全反射されずに出射面１２から光が出射されることとなる。この出射される光の光路Ｌ３１，Ｌ３２，Ｌ３３を破線で図４に示す。なお、コバ１３で全反射する光の全てが出射面１２で再度全反射する訳ではない。なお、このコバ１３の役割は、ＬＥＤ部材３の出射範囲を見かけ上広くするものである。 FIG. 4 shows an optical path L3 of the light emitted from the emission position N2 of the LED member 3 to the lower region of the concave surface 11 with the light that has spread widely. The light applied to the lower region enters the light guide 2 from the concave surface 11 and is then totally reflected by the edge 13. The light taking such a path has a spread angle with respect to the central axis M exceeding 60 degrees. However, by changing the shape of the concave surface 11, it can be 45 degrees or more, or 65 degrees or more. The light totally reflected by the edge 13 is further totally reflected at the exit surface 12. At this time, until the light enters the light guide 2 and repeats total reflection at the exit surface 12 and finally exits from the exit surface of the light guide 2, the light is influenced by light scattering particles. Receiving and multiple scattering. For this reason, in the process of repeating total reflection on the emission surface 12, a part of the light is emitted from the emission surface 12 without being totally reflected. The light paths L31, L32, and L33 of the emitted light are shown by broken lines in FIG. Note that not all of the light totally reflected by the edge 13 is totally reflected again by the emission surface 12. The role of the edge 13 is to apparently widen the emission range of the LED member 3.
　図５には、ＬＥＤ部材３の出射位置Ｎ２から出射された光のうち、図４に示す光よりさらに大きく広がった光が傾斜面２１の鏡面シートに反射してコバ１３の特定の領域Ｑに照射された光の光路を示している。ＬＥＤ部材３から出射された光が領域Ｑに照射されると、その光は、２つの光路Ｌ４，Ｌ５をとる。光路Ｌ４は、ＬＥＤ部材３から出射された光が領域Ｑに当たり、コバ１３から導光体２の内部へと進入する光路である。光路Ｌ５は、ＬＥＤ部材３から出射された光が領域Ｑに当たり、コバ１３の領域Ｑで反射し、その後再度傾斜面２１の鏡面シートに反射してコバ１３の別の領域から導光体２の内部へと進入する光路である。導光体２の内部へと進入した光は、出射面１２にて全反射を繰り返す。このとき、光が導光体２の内部へと進入し出射面１２にて全反射を繰り返し、最後に出射面１２から出射するまでの間は、光は光散乱粒子の影響を受け、多重散乱する。そのため、出射面１２にて全反射を繰り返す過程で、その光の一部は、全反射されずに出射面１２から出射されることとなる。この出射される光の光路Ｌ４１，Ｌ４２，Ｌ５１，Ｌ５２を破線で図５に示す。 In FIG. 5, among the light emitted from the emission position N <b> 2 of the LED member 3, the light that has spread further than the light shown in FIG. 4 is reflected by the mirror surface sheet of the inclined surface 21 and enters the specific region Q of the edge 13. The optical path of the irradiated light is shown. When the light emitted from the LED member 3 is irradiated onto the region Q, the light takes two optical paths L4 and L5. The optical path L4 is an optical path through which the light emitted from the LED member 3 hits the region Q and enters the light guide 2 from the edge 13. In the optical path L5, the light emitted from the LED member 3 hits the region Q, is reflected by the region Q of the edge 13, and then is reflected again by the mirror surface sheet of the inclined surface 21, and from the other region of the edge 13 of the light guide 2 It is an optical path that enters inside. The light that has entered the light guide 2 repeats total reflection at the exit surface 12. At this time, the light is influenced by the light scattering particles until the light enters the inside of the light guide 2 and repeats total reflection at the exit surface 12 and finally exits from the exit surface 12, so that multiple scattering occurs. To do. For this reason, in the process of repeating total reflection on the emission surface 12, a part of the light is emitted from the emission surface 12 without being totally reflected. The light paths L41, L42, L51, and L52 of the emitted light are shown by broken lines in FIG.
　ここで、図４、図５に示すように、コバ１３または保持具４によって反射され、導光体２内に入射した光であって光散乱粒子が無いとした場合の光が出射面１２に入射する入射角をθとし、出射面１２の全反射臨界角をθｃとしたとき、（θｃ×１．７）＞θ＞（θｃ×０．９）の範囲となる入射角θのものは、２０％以上となっている。 Here, as shown in FIGS. 4 and 5, the light that is reflected by the edge 13 or the holder 4 and is incident on the light guide 2 and has no light scattering particles is incident on the emission surface 12. The incident angle θ in the range of (θc × 1.7)> θ> (θc × 0.9), where θ is the incident angle of incidence and θc is the critical total reflection angle of the exit surface 12, 20% or more.
　図６は、ＬＥＤ部材３から出射される光がＬＥＤ部材３の外周に近い側となる出射位置Ｎ４である場合の光路Ｌ６を示している。ＬＥＤ部材３から出射された光がコバ１３の特定の領域Ｒに照射されると、その光は、光路Ｌ６をとる。光路Ｌ６は、まず、コバ１３から導光体２の内部へと透過し、その後凹面１１を全反射し、さらにその後出射面１２から外部へ出射される。なお、光が導光体２の内部へと透過し出射面１２から外部へ出射するまでの間は、光は光散乱粒子の影響を受け、多重散乱する。さらに、ＬＥＤ部材３の出射位置は、凹面１１に複数向かうようにされていても良い。 FIG. 6 shows an optical path L6 in the case where the light emitted from the LED member 3 is the emission position N4 on the side close to the outer periphery of the LED member 3. When the light emitted from the LED member 3 is applied to the specific region R of the edge 13, the light takes an optical path L6. The optical path L6 is first transmitted from the edge 13 to the inside of the light guide 2, then totally reflected by the concave surface 11, and then emitted from the emission surface 12 to the outside. Note that the light is affected by the light scattering particles until the light is transmitted to the inside of the light guide 2 and is emitted from the emission surface 12 to the outside. Furthermore, a plurality of emission positions of the LED member 3 may be directed toward the concave surface 11.
　図７は、発光装置１の上面からの発光状態を示す。また、図８は、発光装置１の側面からの発光状態を示す。図７および図８において、発光状態は、色が白に近づくに従い出射輝度が高くなり、色が黒に近づくに従い出射輝度が低くなるように示している。 FIG. 7 shows a light emission state from the upper surface of the light emitting device 1. FIG. 8 shows a light emission state from the side surface of the light emitting device 1. 7 and 8, the light emission state is shown such that the emission luminance increases as the color approaches white, and the emission luminance decreases as the color approaches black.
　また、図９は、比較対象の構成例を示す図であり、特許文献１に開示されているＬＥＤ電球の構成に近づけるべく、円形板状のＬＥＤ部材９１の外表面に拡散シート９２を配置した発光装置９３の縦断面概要図である。図１０は、発光装置９３の上面からの発光状態を示す。また、図１１は、発光装置９３の側面からの発光状態を示す。発光状態は、図７および図８と同様に示している。なお、発光装置１のＬＥＤ部材３と発光装置９３のＬＥＤ部材９１は同一のものを用い、供給電力も同一とした。よって、出射位置Ｎ１，Ｎ２なども発光装置１のそれと同一である。すなわち、出射範囲をＬＥＤ部材３，９１の全範囲とした場合である。これは、図に示すＬＥＤ部材３，９１の左右方向方向の長さを一辺とした四角形の範囲が出射範囲となることを意味する。 Moreover, FIG. 9 is a figure which shows the structural example of a comparison object, and has arrange | positioned the diffusion sheet 92 on the outer surface of the circular plate-shaped LED member 91 in order to approximate the structure of the LED bulb currently disclosed by patent document 1. FIG. It is a longitudinal cross-sectional schematic diagram of the light-emitting device 93. FIG. 10 shows a light emission state from the upper surface of the light emitting device 93. FIG. 11 shows a light emission state from the side surface of the light emitting device 93. The light emission state is shown in the same manner as in FIGS. The LED member 3 of the light emitting device 1 and the LED member 91 of the light emitting device 93 were the same, and the supplied power was also the same. Therefore, the emission positions N1, N2, etc. are the same as those of the light emitting device 1. That is, the emission range is the entire range of the LED members 3 and 91. This means that a square range with one side of the length in the left-right direction of the LED members 3 and 91 shown in the figure is the emission range.
　図７および図８と、図１０および図１１とを見比べると、発光装置９３よりも発光装置１の方が導光体２全体に光が拡散し、グレアが低減できていることがわかる。すなわち、発光装置９３は、図１０に示すように中央部に高輝度部分、すなわちＬＥＤ部材９１の出射範囲の中央に相当する部分が明確に現われているこれに対し、発光装置１では、図７に示すように中央には高輝度部分はなく、中央を囲むようにして、リング状の高輝度部分が現われている。 7 and 8 are compared with FIGS. 10 and 11, it can be seen that the light emitting device 1 diffuses light to the entire light guide 2 and the glare can be reduced compared to the light emitting device 93. That is, in the light emitting device 93, as shown in FIG. 10, a high brightness portion, that is, a portion corresponding to the center of the emission range of the LED member 91 appears clearly in the central portion. As shown in FIG. 5, there is no high brightness portion in the center, and a ring-like high brightness portion appears around the center.
（本発明の第２の実施の形態に係る発光装置３１について）
　本発明の第２の実施の形態に係る発光装置３１および発光装置３１に用いられる光学素子としての導光体３２の構成について説明する。 (About the light emitting device 31 according to the second embodiment of the present invention)
The structure of the light guide 31 as an optical element used for the light-emitting device 31 and the light-emitting device 31 which concerns on the 2nd Embodiment of this invention is demonstrated.
　図１２は、発光装置３１の縦断面概要図である。発光装置３１は、発光装置１における導光体２の形状が異なる以外は発光装置１と同一の構成である。よって、導光体３２以外の部材については発光装置１と同一の符号を付し、その説明を省略する。 FIG. 12 is a schematic vertical cross-sectional view of the light-emitting device 31. The light emitting device 31 has the same configuration as the light emitting device 1 except that the shape of the light guide 2 in the light emitting device 1 is different. Therefore, members other than the light guide 32 are denoted by the same reference numerals as those of the light emitting device 1 and description thereof is omitted.
　導光体３２は、ＬＥＤ部材３から発せられる光を導光し内部が充実体とされるものである。導光体３２は、ＬＥＤ部材３から発せられる光が入射する部分の奥側が三角錐状にえぐれ、開口側がその三角錐状の底面から続くように円柱状の空間とされる凹面４１を有している。この凹面４１が、一方の面となる。 The light guide 32 guides the light emitted from the LED member 3 and the inside is filled. The light guide 32 has a concave surface 41 which is a cylindrical space so that the back side of the part where the light emitted from the LED member 3 enters is triangular pyramid, and the opening side continues from the triangular pyramid bottom surface. ing. The concave surface 41 is one surface.
　そして、導光体３２は、一方の面とは反対側に、球形をなしＬＥＤ部材３から発せられた光を出射する出射面４２（他方の面）を有している。すなわち、導光体３２は、凹面４１と出射面４２を有するメニスカスレンズである。さらに、導光体３２は、凹面４１の周囲を取り囲み凹面４１の開口側内周面と直角をなす円環状部４３と、発光装置１の導光体２におけるコバ１３と同様に円環状部４３を円錐台の周面状に取り囲む環状の面である円環状部４４を有している。これら円環状部４３，４４を総称してコバ４５ということにする。コバ４５は、ＬＥＤ部材３から発せられ導光体２内に導光された光を反射する。 The light guide 32 has a light emitting surface 42 (the other surface) that emits light emitted from the LED member 3 on a side opposite to the one surface. That is, the light guide 32 is a meniscus lens having a concave surface 41 and an exit surface 42. Furthermore, the light guide 32 includes an annular portion 43 that surrounds the concave surface 41 and forms a right angle with the opening-side inner peripheral surface of the concave surface 41, and an annular portion 43 similar to the edge 13 in the light guide 2 of the light emitting device 1. Has an annular portion 44 which is an annular surface surrounding the circular truncated cone. These annular portions 43 and 44 are collectively referred to as an edge 45. The edge 45 reflects light emitted from the LED member 3 and guided into the light guide 2.
　発光装置３１におけるＬＥＤ部材３から出射された光の光路は、発光装置１のそれと略同様である。また、コバ４５または保持具４によって反射され、導光体３２内に入射した光であって光散乱粒子が無いとした場合の光が出射面４２に入射する入射角をθとし、出射面４２の全反射臨界角をθｃとしたとき、（θｃ×１．７）＞θ＞（θｃ×０．９）の範囲となる入射角θのものは、発光装置１同様２０％以上となっている。 The optical path of the light emitted from the LED member 3 in the light emitting device 31 is substantially the same as that of the light emitting device 1. Further, the incident angle at which the light that is reflected by the edge 45 or the holder 4 and is incident on the light guide 32 and does not have light scattering particles when entering the light exit surface 42 is θ, and the light exit surface 42. The incident angle θ in the range of (θc × 1.7)> θ> (θc × 0.9) is 20% or more like the light emitting device 1 where the total reflection critical angle is θc. .
　図１３は、発光装置３１の上面からの発光状態を示す。また、図１４は、発光装置３１の側面からの発光状態を示す。発光状態は、図７および図８と同様に示している。なお、発光装置３１のＬＥＤ部材３と発光装置１のＬＥＤ装置３は同一のものを用い、供給電力も同一とした。図１３および図１４と、比較対象の図１０および図１１とを見比べると、発光装置９３よりも発光装置３１の方が導光体３２全体に光が拡散し、グレアが低減できていることがわかる。 FIG. 13 shows a light emission state from the upper surface of the light emitting device 31. FIG. 14 shows a light emission state from the side surface of the light emitting device 31. The light emission state is shown in the same manner as in FIGS. The LED member 3 of the light emitting device 31 and the LED device 3 of the light emitting device 1 were the same, and the supplied power was also the same. Comparing FIGS. 13 and 14 with FIGS. 10 and 11 for comparison, it is found that light is diffused in the entire light guide 32 and glare can be reduced in the light emitting device 31 rather than in the light emitting device 93. Recognize.
（本発明の第３の実施の形態に係る発光装置５１について）
　本発明の第３の実施の形態に係る発光装置５１および発光装置５１に用いられる光学素子としての導光体３２の構成について説明する。 (About the light emitting device 51 according to the third embodiment of the present invention)
The structure of the light guide 51 as an optical element used for the light-emitting device 51 and the light-emitting device 51 according to the third embodiment of the present invention will be described.
　図１５は、発光装置５１の縦断面概要図である。発光装置５１は、発光装置３１における保持具４の形状が異なり、導光体３２の厚みが若干大きいこと以外は発光装置３１と同一の構成である。よって、保持具５３以外の部材については発光装置３１と同一の符号を付し、その説明を省略する。 FIG. 15 is a schematic vertical cross-sectional view of the light-emitting device 51. The light emitting device 51 has the same configuration as the light emitting device 31 except that the shape of the holder 4 in the light emitting device 31 is different and the thickness of the light guide 32 is slightly larger. Therefore, members other than the holder 53 are denoted by the same reference numerals as those of the light emitting device 31 and description thereof is omitted.
　保持具５３の図１５における上側から下側までの高さは、保持具４の３倍である。保持具５３は、中央がくり抜かれた円環状の形状をしている。その円環状の内周面は、図１４における上側から下側に向かうに従い円環状の径を小さくする凹形状かつ曲面形状の傾斜面６１となっている。この傾斜面６１には、鏡面となるように鏡面シート（図示省略）が貼付されている。傾斜面６１は、発光装置１の傾斜面２１と同様に凹面鏡となっている。しかし、傾斜面６１は、凹面鏡としなくても良い。 The height from the upper side to the lower side of the holder 53 in FIG. 15 is three times that of the holder 4. The holder 53 has an annular shape with the center cut out. The annular inner peripheral surface is a concave and curved inclined surface 61 that decreases in diameter as it goes from the upper side to the lower side in FIG. A mirror surface sheet (not shown) is attached to the inclined surface 61 so as to be a mirror surface. The inclined surface 61 is a concave mirror similar to the inclined surface 21 of the light emitting device 1. However, the inclined surface 61 may not be a concave mirror.
　導光体３２は、コバ４５が保持具５３の傾斜面６１に対向するように配置されている。また、導光体３２のコバ４５は、保持具５３の縁部６２にて保持されている。ＬＥＤ部材３は、図１５における保持具５３の下側面の円形にくり抜かれたくり抜き部６３に対向するようにして固定されている。その結果、ＬＥＤ部材３の出射位置Ｎ１は、凹面４１に向かうように配置されている。また、コバ４５と傾斜面６１との間は、凹面６１側から縁部６２に向かうに従って隙間の狭くなる間隙６４となっている。 The light guide 32 is disposed so that the edge 45 faces the inclined surface 61 of the holder 53. The edge 45 of the light guide 32 is held by the edge 62 of the holder 53. The LED member 3 is fixed so as to face the cut-out portion 63 cut out in a circular shape on the lower surface of the holder 53 in FIG. As a result, the emission position N1 of the LED member 3 is disposed so as to face the concave surface 41. Further, a gap 64 is formed between the edge 45 and the inclined surface 61 so that the gap becomes narrower from the concave surface 61 side toward the edge portion 62.
　発光装置５１におけるＬＥＤ部材３から出射された光の光路は、発光装置１のそれと略同様である。また、コバ４５または保持具５３によって反射され、導光体３２内に入射した光であって光散乱粒子が無いとした場合の光が出射面４２に入射する入射角をθとし、出射面４２の全反射臨界角をθｃとしたとき、（θｃ×１．７）＞θ＞（θｃ×０．９）の範囲となる入射角θのものは、発光装置１同様２０％以上となっている。 The light path of the light emitted from the LED member 3 in the light emitting device 51 is substantially the same as that of the light emitting device 1. Further, the incident angle at which the light that is reflected by the edge 45 or the holder 53 and is incident on the light guide 32 and does not include light scattering particles is incident on the exit surface 42 is θ, and the exit surface 42 The incident angle θ in the range of (θc × 1.7)> θ> (θc × 0.9) is 20% or more like the light emitting device 1 where the total reflection critical angle is θc. .
　図１６は、発光装置５１の上面からの発光状態を示す。また、図１７は、発光装置５１の側面からの発光状態を示す。発光状態は、図７および図８と同様に示している。なお、発光装置５１のＬＥＤ部材３と発光装置１のＬＥＤ部材３は同一のものを用い、供給電力も同一とした。図１６および図１７と、比較対象の図１０および図１１とを見比べると、発光装置９３よりも発光装置５１の方が導光部３２全体に光が拡散し、グレアが低減できていることがわかる。 FIG. 16 shows a light emission state from the upper surface of the light emitting device 51. FIG. 17 shows a light emission state from the side surface of the light emitting device 51. The light emission state is shown in the same manner as in FIGS. The LED member 3 of the light emitting device 51 and the LED member 3 of the light emitting device 1 were the same, and the supplied power was also the same. When comparing FIGS. 16 and 17 with FIGS. 10 and 11 to be compared, it is found that light is diffused in the entire light guide unit 32 and glare can be reduced in the light emitting device 51 than in the light emitting device 93. Recognize.
（本発明の第４の実施の形態に係る発光装置７１について）
　本発明の第４の実施の形態に係る発光装置７１および発光装置７１に用いられる光学素子としての導光体２の構成について説明する。 (About the light emitting device 71 according to the fourth embodiment of the present invention)
The structure of the light guide 2 as an optical element used in the light emitting device 71 and the light emitting device 71 according to the fourth embodiment of the present invention will be described.
　図１８は、発光装置７１の縦断面概要図である。発光装置７１は、発光装置１における光の出射位置が４箇所となったこと以外は発光装置１と同一の構成である。すなわち、１つのＬＥＤ部材３に４つのＬＥＤ３Ａ，３Ｂ，３Ｃ，３Ｄが配置される構成となっている。よって、各ＬＥＤ部材３Ａ～３Ｄの中心となる出射中心位置Ｐ１，Ｐ２，Ｐ３，Ｐ４とＬＥＤ３Ａ～３Ｄ以外については発光装置１と同一の符号を付し、その説明を省略する。ここで、出射中心位置Ｐ１～Ｐ４は、コバ１３と凹面１１との境界位置に対向する位置である。 FIG. 18 is a schematic vertical cross-sectional view of the light emitting device 71. The light emitting device 71 has the same configuration as that of the light emitting device 1 except that the light emitting device 1 has four light emission positions. That is, four LED 3A, 3B, 3C, 3D is arranged on one LED member 3. Therefore, the same reference numerals as those of the light emitting device 1 are used except for the emission center positions P1, P2, P3, P4 and the LEDs 3A to 3D which are the centers of the LED members 3A to 3D, and the description thereof is omitted. Here, the emission center positions P1 to P4 are positions facing the boundary position between the edge 13 and the concave surface 11.
　図１９は、発光装置７１のＬＥＤ部材３の平面図である。正方形の部位がＬＥＤ３Ａ～３Ｄで、その各中心位置が出射中心位置Ｐ１～Ｐ４となる。発光装置７１におけるＬＥＤ部材３から出射された光の光路は、発光装置１のそれと略同様である。 FIG. 19 is a plan view of the LED member 3 of the light emitting device 71. The square portions are LEDs 3A to 3D, and their center positions are emission center positions P1 to P4. The optical path of light emitted from the LED member 3 in the light emitting device 71 is substantially the same as that of the light emitting device 1.
　図２０は、発光装置７１の上面からの発光状態を示す。また、図２１は、発光装置７１の側面からの発光状態を示す。図２０および図２１において、発光状態は、色が白に近づくに従い出射輝度が高くなり、色が黒に近づくに従い出射輝度が低くなるように示している。 FIG. 20 shows a light emission state from the upper surface of the light emitting device 71. FIG. 21 shows a light emission state from the side surface of the light emitting device 71. 20 and 21, the light emission state is shown such that the emission luminance increases as the color approaches white and the emission luminance decreases as the color approaches black.
　また、図２２は、比較例の発光装置９３において、図１８，図１９に示すＬＥＤ部材３を用いた比較例２を示すもので、発光装置の上面からの発光状態を示す。また、図２３は、比較例２の発光装置の側面からの発光状態を示す。発光状態は、図２０および図２１と同様に示している。なお、比較例２の発光装置では、発光装置７１のＬＥＤ部材３と同一のものを用い、供給電力も同一とした。 FIG. 22 shows a comparative example 2 using the LED member 3 shown in FIGS. 18 and 19 in the light emitting device 93 of the comparative example, and shows a light emission state from the upper surface of the light emitting device. FIG. 23 shows a light emission state from the side surface of the light emitting device of Comparative Example 2. The light emission state is shown in the same manner as in FIGS. In addition, in the light-emitting device of the comparative example 2, the same thing as the LED member 3 of the light-emitting device 71 was used, and the power supply was also made the same.
　図２０および図２１と、図２２および図２３とを見比べると、比較例２の発光装置よりも発光装置７１の方が導光体２全体に光が拡散し、グレアが低減できていることがわかる。 20 and FIG. 21, and FIG. 22 and FIG. 23, the light emitting device 71 diffuses light throughout the light guide 2 and the glare can be reduced compared to the light emitting device of Comparative Example 2. Recognize.
（本発明の実施の形態によって得られる主な効果）
　本発明の実施の形態に係る導光体２，３２は、内部が充実体とされ、凹面１１，４１などから入射された光を導光し出射面１２，４２から出射するメニスカスレンズとし、メニスカスレンズを光を拡散する光散乱粒子が含有された光拡散体で形成した。このため、凹面１１，４１の形状を変えることで配光角を簡単に制御でき、しかもグレアを減少させることができる。また、発光装置１，３１，５１，７１は、出射面１２，４２において光の一部を全反射させ、一方、光の一部を出射させる光路を形成できる。すなわち、出射面１２，４２にて全反射を繰り返す過程で、全反射されずに出射面１２，４２から光が出射される光が存在する。また、全反射をせずに出射面１２，４２から出射する光の方向も拡散される。そのため、出射する光を拡散してグレアを低減できる。 (Main effects obtained by the embodiment of the present invention)
The light guides 2 and 32 according to the embodiment of the present invention are solid inside, and are meniscus lenses that guide the light incident from the concave surfaces 11 and 41 and emit the light from the output surfaces 12 and 42. The lens was formed of a light diffuser containing light scattering particles that diffuse light. For this reason, the light distribution angle can be easily controlled by changing the shapes of the concave surfaces 11 and 41, and the glare can be reduced. The light emitting devices 1, 31, 51, 71 can form an optical path that totally reflects part of the light on the emission surfaces 12, 42, while emitting part of the light. That is, in the process of repeating total reflection at the emission surfaces 12 and 42, there is light that is emitted from the emission surfaces 12 and 42 without being totally reflected. Further, the direction of light emitted from the emission surfaces 12 and 42 without being totally reflected is also diffused. Therefore, glare can be reduced by diffusing outgoing light.
　また、出射面１２，４２側が球形をなし、凹面１１，４１と出射面１２，４２とをつなぐ境界部となるコバ１３，４５が、環状の凸面となっている。そのため、中心軸Ｍに対して大きな角度で導光体２，３２に進入してきた光をコバ１３，４５の環状の面にて全反射させやすい。 Also, the exit surfaces 12 and 42 side is spherical, and the edges 13 and 45 that serve as boundaries connecting the concave surfaces 11 and 41 and the exit surfaces 12 and 42 are annular convex surfaces. Therefore, the light that has entered the light guides 2 and 32 at a large angle with respect to the central axis M is easily totally reflected by the annular surfaces of the edges 13 and 45.
　また、コバ１３，４５が凹面１１，４１から進入してきた光を全反射し、出射面１２，４２側へ光を導くため、ＬＥＤ部材３の出射部位外からも輝度を発生させ、輝度を均一にし、グレアをより防止する。 Further, since the edges 13 and 45 totally reflect the light entering from the concave surfaces 11 and 41 and guide the light to the emission surfaces 12 and 42, the luminance is generated from outside the emission part of the LED member 3, and the luminance is uniform. And prevent glare more.
　また、保持具４，５３が、光を導光体２，３２側に反射する反射面を有しているため、保持具４，５３の方向に漏れる光がある場合でも、その光を導光体２，３２へと戻し、発光装置１，３１，５１，７１の発光効率を高める。また、保持具４，５３の反射面によって光を全反射し、導光体２，３２側に導くため、ＬＥＤ部材３の出射部位外からも輝度を発生させ、輝度を均一にし、グレアをより防止できる。 Moreover, since the holders 4 and 53 have a reflection surface that reflects light toward the light guides 2 and 32, even when there is light leaking in the direction of the holders 4 and 53, the light is guided. Returning to the bodies 2 and 32, the luminous efficiency of the light emitting devices 1, 31, 51, 71 is increased. In addition, since the light is totally reflected by the reflecting surfaces of the holders 4 and 53 and guided to the light guides 2 and 32 side, the brightness is generated from the outside of the emission part of the LED member 3, the brightness is made uniform, and the glare is further increased. Can be prevented.
　また、発光装置１、３１，５１，７１において、コバ１３，４５または保持具４，５３によって反射され、導光体２，３２内に入射した光であって光散乱粒子が無いとした場合の光が出射面１２，４２に入射する入射角をθとし、出射面１２，４２の全反射臨界角をθｃとしたとき、（θｃ×１．７）＞θ＞（θｃ×０．９）の範囲となる入射角θのものは、２０％以上となっている。そのため、出射面１２，４２における光の全反射の確率が高まり、導光体２，３２の出射面１２，４２の全体から輝度を発生させることができる。この範囲内の光は、導光体２，３２内部で全反射する回数を抑えることができ、高い出射効率を維持できる。また、（θｃ×１．７）＞θ＞（θｃ×１．１）の範囲となる入射角θのものが、３０％以上となることが、より好ましい。この範囲の光は、散乱を受けた際でも全反射し導光体２，３２の側面に出射される確率が高くなり、側面から見た場合でも輝度が均一になる。 Further, in the light emitting devices 1, 31, 51, 71, the light that is reflected by the edges 13, 45 or the holders 4, 53 and is incident on the light guides 2, 32 and has no light scattering particles. When the incident angle at which light is incident on the exit surfaces 12 and 42 is θ, and the total reflection critical angle of the exit surfaces 12 and 42 is θc, (θc × 1.7)> θ> (θc × 0.9) The incident angle θ in the range is 20% or more. Therefore, the probability of total reflection of light on the exit surfaces 12 and 42 is increased, and brightness can be generated from the entire exit surfaces 12 and 42 of the light guides 2 and 32. Light within this range can suppress the number of times of total reflection inside the light guides 2 and 32, and can maintain high emission efficiency. Moreover, it is more preferable that the incident angle θ in the range of (θc × 1.7)> θ> (θc × 1.1) is 30% or more. Light in this range has a high probability of being totally reflected and emitted to the side surfaces of the light guides 2 and 32 even when scattered, and the luminance is uniform even when viewed from the side surface.
　また、導光体２，３２には、透光性シリコーン粒子からなる光散乱粒子が含有されている。そのため、従来の光拡散シートを用いた場合の発光装置９３の全体の明るさ（図１０および図１１に示す）に比べて、発光装置１，３１，５１，７１の全体の明るさ（それぞれ図７および図８、図１３および図１４、図１６および図１７、図２０および図２１に示す）が明るい。これは、この光散乱粒子による光拡散は、光吸収の程度が低いためである。 Further, the light guides 2 and 32 contain light scattering particles made of translucent silicone particles. Therefore, compared to the overall brightness of the light emitting device 93 (shown in FIGS. 10 and 11) when a conventional light diffusion sheet is used, the overall brightness of the light emitting devices 1, 31, 51, 71 (respectively illustrated). 7 and 8, FIG. 13 and FIG. 14, FIG. 16 and FIG. 17, FIG. 20 and FIG. This is because light diffusion by the light scattering particles has a low degree of light absorption.
（他の形態）
　以上、本発明の実施の形態における導光体２，３２およびそれを用いた発光装置１，３１，５１，７１について説明したが、本発明の要旨を逸脱しない限り種々変更実施可能である。 (Other forms)
The light guides 2 and 32 and the light-emitting devices 1, 31, 51 and 71 using the light guides 2 and 32 in the embodiment of the present invention have been described above, but various modifications can be made without departing from the gist of the present invention.
　本発明の実施の形態に係る導光体２，３２は、内部が充実体とされ、凹面１１，４１から入射された光を導光し出射面１２，４２から出射するメニスカスレンズとしている。そして、メニスカスレンズは、光を拡散する光散乱粒子を含有する光拡散体で形成している。しかし、メニスカスレンズは、たとえばポリカーボネート樹脂に光拡散体としてのシリコーン粒子を分散させたもの等としても良い。 The light guides 2 and 32 according to the embodiment of the present invention are solid bodies and are meniscus lenses that guide the light incident from the concave surfaces 11 and 41 and emit the light from the output surfaces 12 and 42. The meniscus lens is formed of a light diffuser that contains light scattering particles that diffuse light. However, the meniscus lens may be, for example, one in which silicone particles as a light diffuser are dispersed in a polycarbonate resin.
　また、光拡散体として光散乱粒子を用いる場合には、光散乱粒子の材質、形状、粒径等の諸条件を適宜設定できる。たとえば、光散乱粒子は、その粒子径が２μｍから９μｍの球状かつ透光性のシリコーン粒子としている。しかし、光散乱粒子は、導光体２内の光を多重散乱するものであれば、その材質、形状、粒子径等を問わず、種々のものを用いることができる。ただし、導光体２，３２において入射光の前方散乱を適切な範囲で大きくするためには、粒子径が２μｍから９μｍ、より好ましくは５μｍから９μｍの球状かつ透光性のシリコーン粒子を用いることが好ましい。 In addition, when using light scattering particles as the light diffuser, various conditions such as the material, shape, and particle size of the light scattering particles can be set as appropriate. For example, the light scattering particles are spherical and translucent silicone particles having a particle diameter of 2 μm to 9 μm. However, as the light scattering particles, various particles can be used regardless of their materials, shapes, particle diameters, etc., as long as they scatter multiple light in the light guide 2. However, in order to increase the forward scattering of incident light in an appropriate range in the light guides 2 and 32, spherical and translucent silicone particles having a particle diameter of 2 μm to 9 μm, more preferably 5 μm to 9 μm, should be used. Is preferred.
　また、出射面１２，４２側が球形（ドーム状）をなし、凹面１１，４１と出射面１２，４２とをつなぎ、ＬＥＤ部材３側に突出するコバ１３，４５が、環状の面となっている。しかし、出射面１２，４２側は楕円球のような形状等としても良い。また、コバ１３，４５は、環状の面ではなく、たとえば一部環状が途切れていても良い。また、ＬＥＤ部材３側に突出するコバ１３，４５を設けないようにしても良い。 Further, the emission surfaces 12 and 42 are spherical (dome-shaped), and the edges 13 and 45 that connect the concave surfaces 11 and 41 and the emission surfaces 12 and 42 and protrude toward the LED member 3 are annular surfaces. . However, the exit surfaces 12 and 42 may have an elliptical sphere shape. Further, the edges 13 and 45 are not annular surfaces, and for example, a part of the annular shape may be interrupted. Further, the edges 13 and 45 protruding to the LED member 3 side may not be provided.
　また、凹面１１，４１は、平滑面とされているが、光を散乱するシボ状になっていても良い。凹面１１，４１をシボ状とすることによって、導光体２，３２内における光の拡散・散乱が促進される。 Moreover, although the concave surfaces 11 and 41 are smooth surfaces, they may have a grain shape that scatters light. By making the concave surfaces 11 and 41 have a textured shape, the diffusion and scattering of light in the light guides 2 and 32 is promoted.
　また、凹面１１，４１と出射面１２，４２との境界部となるコバ１３，４５が凹面１１，４１から導光体２，３２へ進入してきた光を全反射している。しかし、たとえばコバ１３，４５にて光が透過され、保持具４，５３によって反射されることとしても良い。 Further, the edges 13 and 45 that are the boundary portions between the concave surfaces 11 and 41 and the emission surfaces 12 and 42 totally reflect the light that has entered the light guides 2 and 32 from the concave surfaces 11 and 41. However, for example, light may be transmitted through the edges 13 and 45 and reflected by the holders 4 and 53.
　また、発光装置１，３１，５１，７１は、導光体２，３２を凹面１１，４１側から支える保持具４，５３を有し、保持具４，５３が、光を導光体２，３２側に反射する反射面（傾斜面２１に貼付されている鏡面シート）を有している。しかし、発光装置１，３１，５１，７１は、保持具４，５３とその反射面を省略しても良い。たとえば、コバ１３，４５の面にプリズムを形成して、光を反射することとしても良い。また、傾斜面２１，６１に鏡面シートを貼付するのではなく、蒸着、磨き加工等によって鏡面を形成しても良い。 The light emitting devices 1, 31, 51, 71 have holders 4, 53 that support the light guides 2, 32 from the concave surfaces 11, 41 side, and the holders 4, 53 transmit light to the light guides 2, 2. It has a reflecting surface (mirror sheet affixed to the inclined surface 21) that reflects to the 32 side. However, the light-emitting devices 1, 31, 51, 71 may omit the holders 4, 53 and their reflecting surfaces. For example, a prism may be formed on the surfaces of the edges 13 and 45 to reflect light. Further, the mirror surface may be formed by vapor deposition, polishing, or the like instead of attaching the mirror sheet to the inclined surfaces 21 and 61.
　また、発光装置１、３１，５３において、コバ１３，４５または保持具４，５３によって反射され、導光体２，３２内に入射した光であって光散乱粒子が無いとした場合の光が出射面１２，４２に入射する入射角をθとし、出射面１２，４２の全反射臨界角をθｃとしたとき、（θｃ×１．７）＞θ＞（θｃ×０．９）の範囲となる入射角θのものは、　２０％以上となっている。しかし、その値は２０％未満としても良い。 Further, in the light emitting devices 1, 31, and 53, the light that is reflected by the edges 13 and 45 or the holders 4 and 53 and is incident on the light guides 2 and 32 without light scattering particles is generated. When the incident angle incident on the exit surfaces 12 and 42 is θ and the total reflection critical angle of the exit surfaces 12 and 42 is θc, the range of (θc × 1.7)> θ> (θc × 0.9) The incident angle θ is 20% or more. However, the value may be less than 20%.
　また、ＬＥＤ部材３の出射位置Ａ，Ｂは、凹面１１に向かうようにされている。そして、ＬＥＤ部材３の各ＬＥＤ３Ａ～３Ｄの各出射中心位置Ｐ１～Ｐ４は、凹面１１とコバ１３の境界位置に向かうようにされている。しかし、各ＬＥＤ３Ａ～３Ｄの出射中心位置は、コバ１３，４５の部分に向かうようにされていても良い。また、ＬＥＤ部材３の出射位置は、凹面１１およびコバ１３，４５に向かうようにされていても良い。この場合、ＬＥＤは、複数個用いられる。 Further, the emission positions A and B of the LED member 3 are directed toward the concave surface 11. The emission center positions P1 to P4 of the LEDs 3A to 3D of the LED member 3 are directed to the boundary position between the concave surface 11 and the edge 13. However, the emission center positions of the LEDs 3A to 3D may be directed toward the edge portions 13 and 45. Further, the emission position of the LED member 3 may be directed toward the concave surface 11 and the edges 13 and 45. In this case, a plurality of LEDs are used.
　また、発光部材はＬＥＤに限定されず、有機エレクトロルミネッセンス（Organic
Electro-Luminescence、OEL、有機EL）、無機エレクトロルミネッセンス（Inorganic Electro-Luminescence、IEL、無機EL）、レーザー光等の他の発光部材を用いることができる。さらに、ＬＥＤにはチップ型のものを用いているが、レンズ付きのＬＥＤを用いることができる。 In addition, the light emitting member is not limited to the LED, but organic electroluminescence (Organic
Other light-emitting members such as Electro-Luminescence (OEL, organic EL), inorganic electroluminescence (IEL, inorganic EL), and laser light can be used. Furthermore, although a chip type LED is used, an LED with a lens can be used.
　１，３１，５１，７１　発光装置
　２，３２　導光体（光学素子、メニスカスレンズ）
　３　ＬＥＤ部材（発光部材）
　４，５３　保持具
１１，４１　凹面（一方の面）
１２，４２　出射面（他方の面）
１３，４５　コバ
　θ　入射角
　θｃ　全反射臨界角 1, 31, 51, 71 Light-emitting device 2, 32 Light guide (optical element, meniscus lens)
3 LED members (light emitting members)
4,53 Holder 11,41 Concave surface (one surface)
12, 42 Output surface (the other surface)
13,45 edge θ Incident angle θc Total reflection critical angle

Claims (7)

  1. 　内部が充実体とされ、一方の面から入射された光を導光し他方の面から出射する光学素子において、
    　上記一方の面を凹面とし、上記他方の面を凸面としたメニスカスレンズとし、上記メニスカスレンズを上記光を拡散する光拡散体で形成したことを特徴とする光学素子。     In the optical element that the inside is a solid body, guides light incident from one surface and emits it from the other surface,
    An optical element comprising: a meniscus lens having a concave surface on the one surface and a convex surface on the other surface; and the meniscus lens is formed of a light diffuser that diffuses the light.
  2. 　請求項１記載の光学素子において、
    　前記他方の面側が球形をなし、
    　前記一方の面と前記他方の面との境界部となる前記メニスカスレンズのコバが、球形の面とは反対側に突出した環状の面となっていることを特徴とする光学素子。     The optical element according to claim 1, wherein
    The other surface side is spherical,
    An optical element, wherein an edge of the meniscus lens serving as a boundary portion between the one surface and the other surface is an annular surface protruding to the opposite side of the spherical surface.
  3. 　請求項１記載の光学素子において、
    　前記一方の面は、前記光を散乱するシボ状になっていることを特徴とする光学素子。     The optical element according to claim 1, wherein
    The one surface has an embossed shape that scatters the light.
  4. 　発光部材と、内部が充実体とされ、上記発光部材から発せられる光が一方の面から入射され他方の面から出射する光学素子とを有する発光装置において、
    　上記光学素子は、上記一方の面を凹面とし、上記他方の面を凸面としたメニスカスレンズとされ、このメニスカスレンズは、上記光を拡散する光拡散体で形成されていることを特徴とする発光装置。     In a light-emitting device having a light-emitting member and an optical element in which the inside is a solid body and light emitted from the light-emitting member is incident from one surface and exits from the other surface,
    The optical element is a meniscus lens having one surface as a concave surface and the other surface as a convex surface, and the meniscus lens is formed of a light diffuser that diffuses the light. apparatus.
  5. 　請求項４記載の発光装置において、
    　前記一方の面と前記他方の面との境界部となる前記メニスカスレンズのコバが前記一方の面から進入してきた光を全反射することを特徴とする発光装置。     The light-emitting device according to claim 4.
    The light emitting device according to claim 1, wherein the edge of the meniscus lens serving as a boundary portion between the one surface and the other surface totally reflects light entering from the one surface.
  6. 　請求項４記載の発光装置において、
    　前記光学素子を前記一方の面側から支える保持具を有し、上記保持具が、前記光を前記光学素子側に反射する反射面を有していることを特徴とする発光装置。     The light-emitting device according to claim 4.
    A light-emitting device, comprising: a holder that supports the optical element from the one surface side; and the holder has a reflective surface that reflects the light toward the optical element.
  7. 　請求項５記載の発光装置において、
    　前記コバまたは前記保持具によって反射され、前記メニスカスレンズ内に入射した光であって光散乱体が無いとした場合の光が前記他方の面に入射する入射角をθとし、前記他方の面の全反射臨界角をθｃとしたとき、（θｃ×１．７）＞θ＞（θｃ×０．９）の範囲となる入射角θのものを２０％以上としたことを特徴とする発光装置。     The light-emitting device according to claim 5.
    The incident angle at which the light incident on the other surface is reflected by the edge or the holder and is incident on the meniscus lens without the light scatterer is defined as θ. A light-emitting device having an incident angle θ in a range of (θc × 1.7)>θ> (θc × 0.9) when the total reflection critical angle is θc is 20% or more.
PCT/JP2010/063535 2009-08-25 2010-08-10 Optical element and light emitting device WO2011024641A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP2009194457A JP5543157B2 (en) 2009-08-25 2009-08-25 Optical element and light emitting device
JP2009-194457 2009-08-25

Publications (1)

Publication Number Publication Date
WO2011024641A1 true WO2011024641A1 (en) 2011-03-03

Family

ID=43627747

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2010/063535 WO2011024641A1 (en) 2009-08-25 2010-08-10 Optical element and light emitting device

Country Status (2)

Country Link
JP (1) JP5543157B2 (en)
WO (1) WO2011024641A1 (en)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104317100A (en) * 2014-10-13 2015-01-28 青岛海信电器股份有限公司 Luminescent device and backlight source
CN105258074A (en) * 2014-07-18 2016-01-20 欧司朗有限公司 Lens and lighting device comprising same
WO2016193074A1 (en) * 2015-05-29 2016-12-08 Osram Opto Semiconductors Gmbh Optoelectronic component having a radiation source
CN106949383A (en) * 2017-04-01 2017-07-14 杭州有人光电技术有限公司 A kind of illuminator of utilization LIF
WO2018096041A1 (en) * 2016-11-25 2018-05-31 Osram Opto Semiconductors Gmbh Component with an optoelectronic part

Families Citing this family (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN203731110U (en) * 2011-06-24 2014-07-23 松下电器产业株式会社 Light source for lighting
JP5059988B1 (en) * 2011-06-24 2012-10-31 パナソニック株式会社 Light source for illumination
RU2639980C2 (en) * 2011-10-19 2017-12-25 Филипс Лайтинг Холдинг Б.В. Lighting device with circular distribution of light
JP2015111497A (en) * 2012-03-30 2015-06-18 パナソニック株式会社 Lamp
JP6332491B1 (en) * 2017-02-13 2018-05-30 オムロン株式会社 LASER LIGHTING DEVICE AND PERSONAL MONITORING SENSOR HAVING THE SAME
CN117628423A (en) * 2022-08-12 2024-03-01 巨铠精密工业股份有限公司 Lamp set

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH02155279A (en) * 1988-10-05 1990-06-14 Hewlett Packard Co <Hp> Lamp
JP2002043629A (en) * 2000-07-24 2002-02-08 Yamakawa Akira Led projector and lens body for use therein
JP2002228921A (en) * 2001-01-29 2002-08-14 Rabo Sufia Kk Bulk type lens, light emitting body using the same, illuminator and optical information system
JP2004253477A (en) * 2003-02-18 2004-09-09 Stanley Electric Co Ltd Light emitting diode array light source
WO2007032187A1 (en) * 2005-08-24 2007-03-22 World Wide Engineering Co., Ltd. Led lamp light source and automatically lit led desk lamp upon power failure
JP2009054995A (en) * 2007-08-24 2009-03-12 Cree Inc Package of light-emitting device using light scattering particles of different sizes

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH02155279A (en) * 1988-10-05 1990-06-14 Hewlett Packard Co <Hp> Lamp
JP2002043629A (en) * 2000-07-24 2002-02-08 Yamakawa Akira Led projector and lens body for use therein
JP2002228921A (en) * 2001-01-29 2002-08-14 Rabo Sufia Kk Bulk type lens, light emitting body using the same, illuminator and optical information system
JP2004253477A (en) * 2003-02-18 2004-09-09 Stanley Electric Co Ltd Light emitting diode array light source
WO2007032187A1 (en) * 2005-08-24 2007-03-22 World Wide Engineering Co., Ltd. Led lamp light source and automatically lit led desk lamp upon power failure
JP2009054995A (en) * 2007-08-24 2009-03-12 Cree Inc Package of light-emitting device using light scattering particles of different sizes

Cited By (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105258074A (en) * 2014-07-18 2016-01-20 欧司朗有限公司 Lens and lighting device comprising same
WO2016008637A1 (en) * 2014-07-18 2016-01-21 Osram Gmbh Lens for led illumination
US9890922B2 (en) 2014-10-13 2018-02-13 Hisense Electric Co., Ltd. Light emitting device and backlight source
CN104317100A (en) * 2014-10-13 2015-01-28 青岛海信电器股份有限公司 Luminescent device and backlight source
US10175465B2 (en) 2015-05-29 2019-01-08 Osram Opto Semiconductors Gmbh Optoelectronic component having a radiation source
WO2016193074A1 (en) * 2015-05-29 2016-12-08 Osram Opto Semiconductors Gmbh Optoelectronic component having a radiation source
DE112016002421B4 (en) 2015-05-29 2022-03-31 OSRAM Opto Semiconductors Gesellschaft mit beschränkter Haftung OPTOELECTRONIC COMPONENT WITH A RADIATION SOURCE
WO2018096041A1 (en) * 2016-11-25 2018-05-31 Osram Opto Semiconductors Gmbh Component with an optoelectronic part
CN109983388A (en) * 2016-11-25 2019-07-05 奥斯兰姆奥普托半导体股份有限两合公司 Component with electro-optical components
US11165004B2 (en) 2016-11-25 2021-11-02 Osram Oled Gmbh Component with an optoelectronic part
DE102016122770B4 (en) 2016-11-25 2022-01-05 OSRAM Opto Semiconductors Gesellschaft mit beschränkter Haftung Component with an optoelectronic component
US11824147B2 (en) 2016-11-25 2023-11-21 Osram Oled Gmbh Component with an optoelectronic part
CN106949383A (en) * 2017-04-01 2017-07-14 杭州有人光电技术有限公司 A kind of illuminator of utilization LIF
CN106949383B (en) * 2017-04-01 2023-03-21 安徽仁和光电科技有限公司 Illumination system utilizing laser to induce fluorescence

Also Published As

Publication number Publication date
JP2011049233A (en) 2011-03-10
JP5543157B2 (en) 2014-07-09

Similar Documents

Publication Publication Date Title
JP5543157B2 (en) Optical element and light emitting device
JP5172592B2 (en) Optical element and light emitting device
JP5656461B2 (en) Light emitting device
US8616746B2 (en) Optical element and light-emitting device
JP5306799B2 (en) Optical element and light emitting device
RU2639980C2 (en) Lighting device with circular distribution of light
JP6223746B2 (en) Single-sided light-emitting transparent light guide plate and surface light-emitting device using this light guide plate
JP5351354B2 (en) Light distribution control lens, light source device using the same, and lighting fixture
CN107614964B (en) Light flux controlling member, light emitting device, and lighting device
JP2012160666A (en) Light source module and lighting device
JP6214151B2 (en) Lighting device
JP2011249141A (en) Light emitting device
JP5953021B2 (en) Light guide and lighting device
TW201414957A (en) Illumination device
JP6309660B2 (en) Light guide and light emitting device
JP6056056B2 (en) LED lighting device
JP5363884B2 (en) Light emitting device and optical element
JP5336879B2 (en) Optical element, light emitting device and road light
JP6062618B2 (en) Light guide and lighting device
JP5401331B2 (en) Optical element and light emitting device
JP6012972B2 (en) Lighting device
JP7287491B2 (en) Light source device
TWI588401B (en) Direct type of lighting
JP5712271B2 (en) Optical element and light emitting device
CN113531409A (en) Lighting device

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 10811691

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 10811691

Country of ref document: EP

Kind code of ref document: A1