JP2013043539A - Illuminating device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an illuminating device having improved light utilization efficiency.SOLUTION: The illuminating device 10A includes a substrate 1, a first illumination part 2 emitting first illumination light, and a second illumination part 3 emitting second illumination light in a range narrower than the first illumination part 2. The first illumination part 2 has a light transmission body 12 disposed along the substrate 1, and a first light source 11 obtaining the first illumination light L12 by introducing light to the light transmission body 12. The second illumination part 3 has a second light source 13 mounted on the substrate 1, and an optical path changing part 14A converting light from the second light source 13 into second illumination light L24 of which the emission range is narrowed. The optical path changing part 14A has a light transmissive member 20 which transmits light from the second light source 13, and a light condensing element 21 which narrows the emission range of the light having passed through the light transmissive member 20. The light transmissive member 20 is plate-shaped and comprised of a material of which the refraction factor is greater than 1, and makes light from the second light source 13 incident from one surface 20a, transmits the incident light while suppressing a spreading angle, and emits the light from the other surface 20b to the light condensing element 21.

Description

  The present invention relates to an illuminating device that can be used for a vehicle interior lamp or the like.

As shown in FIG. 24, the lighting device includes a light emitting device 100 including a light emitting unit 103 including a light source 101 and a reflector 102, and a lens 104 provided on the opening side of the reflector 102 (Patent Document). 1). The reflector 102 can reflect the light from the light source 101 and direct it toward the opening. The light emitting unit 103 is movable along the optical axis direction of the lens 104.
In the light emitting device 100, the light emission range can be adjusted by adjusting the distance between the light emitting unit 103 and the lens 104, and illumination light having a desired spot diameter can be obtained.

As a lighting device used for a vehicle interior light or the like, a room lamp that illuminates a wide range (for example, the entire interior of the vehicle) and a map lamp that selectively illuminates a narrow range (for example, a driver or a passenger in a passenger seat) There is something with. The map lamp is preferably used by mounting a top view type LED on a substrate.
Since the map lamp requires light irradiation in a narrow range, the above-described light-emitting device 100 capable of adjusting the light emission range can be applied, but the light-emitting device 100 has a distance between the light-emitting unit 103 and the lens 104. Depending on the situation, there is a problem that the amount of the light L26 that comes off the lens 104 increases and the light utilization efficiency decreases.
Further, since the light emitting device 100 includes the reflector 102, the light source cannot be mounted on the substrate, so that it is difficult to apply to a map lamp.

Japanese Patent No. 4061637

  This invention is made | formed in view of the said situation, and it aims at providing the illuminating device which can improve the utilization efficiency of light.

In order to solve the above problems, the present invention provides the following configuration.
The present invention includes a substrate, a first illumination unit that emits first illumination light, and a second illumination unit that emits second illumination light in a narrower range than the first illumination unit, and the first illumination unit includes , A sheet-like light guide along one surface of the substrate, and a first light source that introduces light into the light guide and propagates it in the surface direction to obtain the first illumination light, and the second light source. The illumination unit includes a second light source mounted on one surface side of the substrate, and an optical path changing unit that uses the light from the second light source as the second illumination light with a narrow emission range, The optical path changing unit includes a translucent member that transmits light from the second light source, and a condensing element that narrows an emission range of light that has passed through the translucent member, and the translucent member has a refractive index of 1 The plate is made of a large material, and the light from the second light source is incident from one surface and transmitted while suppressing the divergence angle. To provide a lighting device which emits toward the condensing element.
In the translucent member, it is preferable that at least a portion through which the light is transmitted has a substantially constant thickness.
The translucent member is preferably substantially parallel to the substrate.
The optical path changing unit may include a photorefractive element having a prism part that refracts light that has passed through the condensing element and directs the light in a direction inclined with respect to a direction perpendicular to the substrate.
The illuminating device of the present invention includes a plurality of the translucent members having different thicknesses and / or refractive indexes, and a movable body provided with the plurality of translucent members, and the movable body includes the second light source. In addition, the light transmissive member that is movable with respect to the light condensing element and that transmits the light from the second light source by the movement may be selected from the plurality of light transmissive members.
The substrate may include a detection sensor that detects proximity or contact of the detection target.

According to the present invention, since the light transmitting member that transmits the light from the second light source while suppressing the divergence angle is provided, the light from the second light source can be incident on the light collecting element including the wide angle component. . Accordingly, the light use efficiency can be increased.
In addition, since the characteristics of the second irradiation light are determined by the thickness and refractive index of the translucent member, the characteristics (spot diameter, etc.) of the second irradiation light can be arbitrarily set by selecting the thickness and material of the translucent member.
In addition, since the light utilization efficiency can be increased without using a reflector, the second light source can be mounted on the substrate, so that the apparatus can be thinned.

It is sectional drawing which shows typically the principal part of the 1st Embodiment of this invention. It is a schematic diagram which shows the structure of a translucent member and a condensing element. It is a schematic diagram which shows a structure when there is no translucent member. It is a graph which shows a test result. It is a graph which shows a test result. It is a top view which shows an example of a light guide. It is a top view which shows the principal part of the other example of a light guide. It is sectional drawing which shows typically the principal part of the 2nd Embodiment of this invention. It is sectional drawing which shows typically the principal part of the 3rd Embodiment of this invention. FIG. 3 is a structural diagram schematically showing a photorefractive element. It is sectional drawing which shows the principal part of the specific example of 3rd Embodiment of the illuminating device of this invention. It is sectional drawing which shows the 2nd illumination part of the illuminating device of FIG. It is sectional drawing which shows the condensing element and photorefractive element of the illuminating device of FIG. It is an expanded sectional view which shows the condensing element and photorefractive element of the illuminating device of FIG. It is a whole sectional view of the illuminating device of FIG. 11, and is a figure which shows A1-A1 cross section of FIG. It is a whole sectional view of the illuminating device of FIG. 11, and is a figure which shows A2-A2 cross section of FIG. It is a top view of the illuminating device of FIG. It is sectional drawing which decomposes | disassembles and shows the 2nd illumination part of the illuminating device of FIG. 11, and is sectional drawing which follows the X direction of FIG. It is sectional drawing which decomposes | disassembles and shows the 1st illumination part of the illuminating device of FIG. 11, and is sectional drawing which follows the Y direction of FIG. It is sectional drawing of the 1st illumination part of the illuminating device of FIG. It is sectional drawing of an example of the board | substrate which can be used for the illuminating device of FIG. It is a schematic diagram which shows the illuminating device with which a light source can move with respect to a lens. It is a schematic diagram which shows the illuminating device with which a lens can move with respect to a light source. It is a schematic diagram which shows an example of the conventional illuminating device.

The present invention will be described below based on preferred embodiments with reference to the drawings.
FIG. 1 is a cross-sectional view schematically showing a main part of a lighting device 10A according to the first embodiment of the present invention.
The illumination device 10A includes a substrate 1, a first illumination unit 2 that emits first illumination light, a second illumination unit 3 that emits second illumination light in a narrower range than the first illumination unit, and a cover unit 4. ing.
The first illumination unit 2 includes a sheet-like light guide 12 along one surface 1 a of the substrate 1 and a first light source 11 that introduces light into the light guide 12.
A light extraction portion 16 that scatters incident light and extracts (emits) it to the lower surface 12 d side of the light guide 12 can be formed on the upper surface 12 c of the light guide 12.

In the 1st illumination part 2, the light L11 radiate | emitted from the 1st light source 11 injects into the light guide 12 from the edge part 12a, and propagates the inside of the light guide 12 to a surface direction. A part of the light L11 propagating in the light guide 12 is scattered by the light extraction unit 16 and extracted to the lower surface 12d side. Since the light extraction part 16 is formed over the wide range of the upper surface 12c of the light guide 12, the 1st illumination light L12 which is planar light emission is obtained.
The 1st illumination light L12 illuminates the wide range (for example, the whole vehicle interior) in which the illuminating device 10A is installed.

The second illumination unit 3 includes a second light source 13 mounted on one surface 1a of the substrate 1 and an optical path changing unit 14A that uses the light from the second light source 13 as second illumination light with a narrow emission range. Have.
The optical path changing unit 14 </ b> A includes a translucent member 20 that transmits light from the second light source 13 and a condensing element 21 that narrows an emission range of light that has passed through the translucent member 20.
As the condensing element 21, a Fresnel lens, a convex lens, etc. are employable, for example. The Fresnel lens will be described later. As the convex lens, for example, a lens having one or more curved surfaces as a main shape among a spherical surface, an elliptic spherical surface, a paraboloid, a cylindrical surface, and an elliptic cylindrical surface can be used.

Hereinafter, the configuration of the translucent member 20 will be described.
As shown in FIG. 1, the translucent member 20 is a plate-like body (or a sheet-like body) made of a material having a refractive index greater than 1. The refractive index of the translucent member 20 can be determined according to the characteristics of the target irradiation light (spot diameter, etc.). For example, if the refractive index is 1.1 or more, preferably 1.4 or more, the light use efficiency is improved. Since it can raise, it is preferable.
As a material of the translucent member 20, for example, urethane resin (polyurethane resin), acrylic resin, polycarbonate resin, silicone resin, polystyrene resin, polyimide resin, polymethyl methacrylate (PMMA) elastomer, urethane acrylate, or the like can be used.

The translucent member 20 in the illustrated example has a flat plate-like main body portion 20c and an extending portion 20d extending outwardly from the peripheral edge portion in a flange shape.
The main body 20c is a part through which light from the second light source 13 is transmitted. It is preferable that the main body 20c has a substantially constant thickness because the emission range of the emitted light L23 does not excessively widen.
The thickness of the main body 20c can be determined according to the characteristics (spot diameter, etc.) of the intended irradiation light, and can be set to 1 to 5 mm, for example.
If the body portion 20c is too thin, the effect of increasing the light use efficiency is reduced. If the body portion 20c is too thick, the thickness dimension of the lighting device 10A is increased. The light utilization efficiency can be increased without increasing the size.

The translucent member 20 has one surface 20a (incident surface) (upper surface in FIG. 1) facing the second light source 13 and the other surface 20b (exit surface) (lower surface in FIG. 1) facing the light collecting element 21. The second light source 13 and the condensing element 21 are installed. The translucent member 20 is desirable in terms of reducing the thickness of the illumination device 10 because at least the main body portion 20c is substantially parallel to the substrate 1 because the thickness dimension of the optical path changing portion 14 can be suppressed.
In the illustrated example, the main body portion 20 c is disposed at a distance from the second light source 13 and the light collecting element 21. The extending part 20 d is disposed in the gap between the light guide 12 and the cover part 4.

FIG. 2 schematically shows the structure of the translucent member 20. As shown in this figure, the light L21 emitted from the second light source 13 is diffused light having a large divergence angle, but the main body portion 20c is located closer to the second light source 13 than the condensing element 21, and thus has a wide angle. A component (for example, light L21a) also enters the main body 20c.
Since the refractive index of the translucent member 20 is greater than 1, the light L22 incident on the translucent member 20 from one surface 20a has a smaller divergence angle than the light L21 before incidence, and the thickness of the translucent member 20 is increased. Then, the divergence angle increases again on the other surface 20b, and is emitted as light L23.

Since the divergence angle is suppressed in the translucent member 20, the light from the second light source 13 can be incident on the light condensing element 21 including the wide angle component (for example, the light L21a). For this reason, the utilization efficiency of light can be improved.
The light L23 that has passed through the translucent member 20 is emitted as light L24 (second illumination light) with the emission range narrowed by the condensing element 21. The light L24 selectively illuminates a narrow range (for example, a driver or a passenger on the front passenger seat) compared to the first illumination light.

  As shown in FIG. 3, when there is no translucent member 20, the light L <b> 21 emitted from the second light source 13 does not change its divergence angle, so that some of the wide angle components (e.g., light L <b> 21 a) It does not enter. For this reason, the utilization efficiency of light will become low.

As shown in FIG. 2, the translucent member 20 transmits the light from the second light source 13 while suppressing the divergence angle, thereby reducing the amount of light incident on the light collecting element 21 when the translucent member 20 is not present (FIG. 2). The shape is not limited to the illustrated example as long as it can be increased as compared with 3). For example, the thickness of the main body part 20c may not be constant, and the center part may be formed thicker than the peripheral part.
Further, it is desirable that the spread angle of the outgoing light L23 is the same as or smaller than the spread angle of the outgoing light L21 from the second light source 13. The divergence angle of the emitted light L23 may be larger than the divergence angle of the emitted light L21. However, even in that case, it is necessary that the amount of light incident on the condensing element 21 is larger than that in the case where the light transmitting member 20 is not provided. is there.

Next, with reference to FIG. 4 and FIG. 5, the result of the test using the translucent member 20 is demonstrated.
As shown in FIG. 2, a test apparatus was prepared in which a flat light-transmitting member 20 having a certain thickness was installed between the second light source 13 and the light collecting element 21. The second light source 13 is a top view type LED, and the condensing element 21 is a Fresnel lens having a focal length of 5 mm and a diameter of 12 mm. The distance from the 2nd light source 13 to the condensing element 21 was 5 mm.
The second light source 13 emits light, and the illumination light transmitted through the translucent member 20 and the light collecting element 21 is projected onto the screen. The distance from the second light source 13 to the screen was 700 mm.

FIG. 4 shows the result of examining the relationship between the refractive index of the translucent member 20 and the diameter (spot diameter) of irradiation light on the screen. The refractive index of the translucent member 20 was 1.4 to 1.9, and the thickness of the translucent member 20 was 4 mm. As shown in this figure, the larger the refractive index of the translucent member 20, the larger the diameter of the irradiated light.
FIG. 5 shows the results of examining the relationship between the thickness of the translucent member 20 and the diameter (spot diameter) of irradiation light on the screen. The thickness of the translucent member 20 was 0 to 5 mm, and the refractive index of the translucent member 20 was 1.4. As shown in the figure, the diameter of the irradiation light increased as the translucent member 20 was thicker. In addition, thickness 0mm means the case where the translucent member 20 is not provided.
Thus, since the diameter of irradiation light changed according to the refractive index or thickness of the translucent member 20, it turns out that the diameter of irradiation light can be adjusted with the setting of the refractive index and thickness of the translucent member 20. .

6 and 7 are plan views illustrating examples of specific configurations of the light guide body 12 and the translucent member 20.
As shown in FIG. 6, the light guide 12 in this example has a rectangular shape, and two openings 15 are formed apart from each other in the long side direction (the left-right direction in FIG. 6). The opening 15 has a substantially rectangular shape extending in the short side direction of the light guide 12 (the vertical direction in FIG. 6). The central portion 15d of each opening 15 coincides with the planar view position of the central portion of the second light source 13 and the condensing element 21 (see FIG. 1).

  As shown in FIG. 7, the illumination device of this example includes an adjustment mechanism that adjusts the characteristics of the second illumination light. The adjustment mechanism has a movable body 19 provided at a position corresponding to the opening 15. The movable body 19 is a rectangular plate-like body extending along the longitudinal direction (vertical direction in FIG. 7) of the opening 15, and a plurality of movable bodies 19 arranged in a line along the longitudinal direction (vertical direction in FIG. 7). The circular translucent member 20 (20A1-20A4) is provided.

At least two (preferably all) of the translucent members 20A1 to 20A4 have different thicknesses and / or refractive indexes. The translucent members 20A1 to 20A4 may differ from each other only in thickness, or may differ from each other only in refractive index. The translucent members 20A1 to 20A4 may be different in both thickness and refractive index.
It is preferable that the thickness and / or refractive index of the translucent members 20A1 to 20A4 are set so that the diameters (spot diameters) of the second illumination light are different from each other.

The movable body 19 is movable with respect to the second light source 13 and the condensing element 21 in the longitudinal direction of the opening 15 (up and down direction in FIG. 7).
As shown by the arrows in FIG. 7, the position of the movable body 19 is adjusted, and any one of the four translucent members 20 (20 </ b> A <b> 1 to 20 </ b> A <b> 4) is disposed in the central portion 15 d, thereby The viewing position can be matched with the planar view position of the second light source 13 and the light collecting element 21. Thereby, the translucent member 20 that transmits the light from the second light source 13 can be selected. The light transmitted through the translucent member 20 disposed in the central portion 15d becomes the second illumination light through the light collecting element 21.

The characteristics (spot diameter, etc.) of the second illumination light are affected by the thickness and refractive index of the translucent member 20 (see FIGS. 4 and 5). Therefore, for example, when the thicknesses of the four translucent members 20A1 to 20A4 are different from each other, the translucent member 20A1 is the thinnest, and the translucent member 20A4 is the thickest, the translucent member 20A1 is disposed in the central portion 15d. Sometimes the diameter (spot diameter) of the second illumination light is the smallest, and the diameter (spot diameter) of the second illumination light is the largest when the translucent member 20A4 is disposed in the central portion 15d.
Thus, the characteristics (diameter, etc.) of the second irradiation light can be adjusted by adjusting the position of the movable body 19.

  In the example shown in FIG. 7, the translucent members 20A1 to 20A4 are arranged in a line along the vertical direction, but the arrangement of the translucent members 20A1 to 20A4 is not limited thereto, and the movable body 19 is moved. As long as the light transmissive member 20 that transmits light can be selected, a plurality of rows may be selected, or rows may not be formed.

FIG. 8 shows an illuminating device 10B according to the second embodiment of the present invention, and this illuminating device 10B has the same configuration as the illuminating device 10A shown in FIG. 1 except for the translucent member 20B of the optical path changing unit 14B. . In the following description of each embodiment, the same reference numerals are given to the already described configurations, and the description thereof may be omitted or simplified.
The main body 20e of the translucent member 20B is formed thicker than the main body 20c of the translucent member 20 shown in FIG.
The main body 20e in the illustrated example is formed such that the upper surface 20e1 is in contact with (or close to) the second light source 13 and the lower surface 20e2 is in contact with (or close to) the light collecting element 21. That is, the main body portion 20e is provided in the entire thickness range (or substantially the entire thickness range) of the space between the second light source 13 and the light collecting element 21. The thickness range is a range in the thickness direction of the substrate 1.

  In this illuminating device 10B, since the main body portion 20e of the translucent member 20B is provided in the entire thickness range of the space between the second light source 13 and the light condensing element 21, the second light source 13 and the light condensing element 21 are provided. The thickness can be secured by making the most of the space between the two. Therefore, the light utilization efficiency can be maximized.

  FIG. 9 and FIG. 10 are diagrams showing an illuminating device 10C according to the third embodiment of the present invention. As shown in FIG. 9, the optical path changing unit 14 of the illuminating device 10C includes a translucent member 20, a condensing element 21 that narrows an emission range of light that has passed through the translucent member 20, and a photorefractive element that refracts the light. 22.

As shown in FIG. 10, the photorefractive element 22 has one or a plurality of prism portions 23 on one surface 22a (upper surface in FIG. 10) (surface on the second light source 13 side). In the illustrated example, a plurality of prism portions 23 are formed on the surface 22a of the photorefractive element 22 so as to be continuous from side to side.
The other surface 22b (the lower surface in FIG. 10) of the photorefractive element 22 is a flat surface along the substrate 1 and is substantially parallel to the one surface 1a (see FIG. 9) of the substrate 1. For this reason, the photorefractive element 22 is in a posture along the substrate 1.

  The prism part 23 is a polyhedral unevenness (concave and / or convex structure) having an optical path conversion surface for converting the direction of light. In the illustrated example, the prism portion 23 is a convex portion having an inverted V-shaped cross section having a prism surface 23a (optical path conversion surface) and a back surface 23b (optical path conversion surface) adjacent thereto. The prism portion 23 may be a polyhedral concave portion.

  As shown in FIG. 10, the prism surface 23a of the prism portion 23 is inclined at an angle φ with respect to the surface 1a of the substrate 1 (see FIG. 1). The inclination angle and direction of the prism surface 23a are determined according to the required inclination angle and direction of the second illumination light L25. The prism surface 23a in the illustrated example is inclined so as to gradually descend toward the left. In the illustrated example, the back surface 23 b is perpendicular (or substantially perpendicular) to the surface 1 a of the substrate 1.

  As shown in FIG. 9, the light L21 emitted from the second light source 13 passes through the translucent member 20, and the light L23 that has passed through the translucent member 20 enters the condensing element 21 and is emitted as light L24. The light L24 enters the photorefractive element 22 from the prism portion 23 side, and exits from the other surface 22b as outgoing light L25 (second illumination light). The inclination angle (optical axis conversion angle) of the emitted light L25 with respect to the direction V1 perpendicular to the substrate 1 is θ.

Hereinafter, a specific example of the illumination device 10C illustrated in FIG. 9 will be described.
FIG. 11 is a cross-sectional view showing a main part of the lighting device 10 which is a specific example of the lighting device 10C, and is a view showing a cross section (A1-A1 cross section) along the X direction in FIG. FIG. 12 is a cross-sectional view showing the second illumination unit 3 of the illumination device 10. FIG. 13 is a cross-sectional view showing the condensing element 21 and the photorefractive element 22 of the illumination device 10. FIG. 14 is an enlarged cross-sectional view showing the condensing element 21 and the photorefractive element 22. FIG. 15 is an overall cross-sectional view of the illumination device 10 and is a view showing a cross section A1-A1 of FIG. FIG. 16 is an overall cross-sectional view of the illumination device 10 and is a view showing an A2-A2 cross section of FIG. 17. FIG. 17 is a plan view of the illumination device 10. 18 is an exploded cross-sectional view of the second illumination unit 3 of the illumination device 10, and is a cross-sectional view along the X direction of FIG. FIG. 19 is an exploded cross-sectional view of the first illumination unit 2 of the illumination device 10, and is a cross-sectional view along the Y direction of FIG. FIG. 20 is a cross-sectional view of the first lighting unit 2 of the lighting device 10. FIG. 21 is a cross-sectional view of an example of the substrate 1 that can be used in the lighting device 10.

As illustrated in FIGS. 11 and 15 to 17, the illumination device 10 emits the second illumination light in a range narrower than the substrate 1, the first illumination unit 2 that emits the first illumination light, and the first illumination unit 2. The 2nd illumination part 3 which emits, the cover part 4 which covers these, and the flame | frame part 5 to which the cover part 4 is attached are provided.
The illuminating device 10 can be installed, for example, on the ceiling of a vehicle and used as an interior lamp. As shown in FIGS. 15 and 16, the lighting device 10 can be installed in the vehicle by fixing the frame portion 5 to the interior material 6 of the vehicle, for example.

  As shown in FIGS. 16 and 17, the first illumination unit 2 includes a sheet-like light guide 12 installed along one surface 1 a (lower surface or surface) of the substrate 1, and light to the light guide 12. The 1st light source 11 which introduces. The 1st illumination part 2 can be used as a room lamp which illuminates a wide range (for example, the whole vehicle interior).

The first light source 11 is composed of one or a plurality of light sources 11 a mounted on one surface 1 a of the substrate 1. In this example, as illustrated in FIG. 17, the first light source 11 includes a plurality of light sources 11 a, and these light sources 11 a are arranged along one end edge 12 a of the light guide 12.
The one end edge portion 12a provided with the light source 11a in this example is one of the four side portions of the light guide 12 having a substantially rectangular shape in plan view, and more specifically, one end of the light guide 12 having a substantially rectangular shape. Long side.
The light source 11a can be installed in a partial range including the central portion in the length direction of the one end edge portion 12a. The number and positions of the light sources 11a are determined so that the brightness of the first illumination light introduced into the light guide 12 and surface-emitted does not vary.

As shown in FIGS. 19 and 20, the light source 11 a is installed with the light emitting surface 11 b facing the end surface 12 b of the one end edge portion 12 a of the light guide 12.
As the light source 11a, a light emitting diode (hereinafter referred to as LED) (light emitting element) can be used. In addition, the light emitting element used as the light source 11a is not limited to the LED but may be a cold cathode tube.

The light guide 12 is made of a transparent light transmissive resin, and for example, urethane resin, acrylic resin, polycarbonate resin, silicone resin, polystyrene resin, polyimide resin, polymethyl methacrylate (PMMA) elastomer, urethane acrylate, or the like is used. it can.
As shown in FIG. 20, when the thickness T1 of the light guide 12 is set to be equal to or greater than the height H1 of the light source 11a, the light introduction efficiency from the light source 11a is increased, and the luminance of the first illumination light is increased. And the illuminance can be increased.

As shown in FIG. 20, incident light is scattered on the upper surface 12 c (one surface or back surface) which is the surface of the light guide 12 on the substrate 1 side, and the lower surface 12 d (the other surface or surface) of the light guide 12 is scattered. It is possible to form a light extraction portion 16 that is extracted (emitted) to the side. The light extraction portion 16 can be formed in a part or all of the upper surface 12c. By forming the light extraction part 16 in a wide range, the light in the light guide 12 is extracted to the lower surface 12d side as surface light emission (first illumination light).
The light extraction portion 16 can be formed to emit light over the entire area of the light guide 12 by being uniformly formed over the entire area of the upper surface 12c. The 1st illumination part 2 functions as a planar light-emitting device.

  The light extraction unit 16 can be a plurality of microdot-like ink layers (hereinafter simply referred to as microdots) formed by printing, for example. The planar view shape of the minute dots may be arbitrary, such as a circle, an ellipse, or a polygon (such as a rectangle). The minute dots can be formed by a printing method such as a screen printing method, a gravure printing method, or a pad printing method.

As the ink constituting the fine dots, for example, white ink using titanium oxide as a pigment is suitable. Since titanium oxide functions as a white pigment, the ink exhibits a white color. When the titanium oxide content of the ink is 5 to 50% by mass or more, preferably 10 to 40% by mass or more, high luminance can be obtained.
Examples of titanium oxide include rutile type and anatase type, and rutile type titanium oxide is particularly preferable.
In order to emit white light, it is necessary to uniformly scatter the entire visible light. Here, considering the relationship between the wavelength to be scattered and the particle size of titanium oxide, the particle size of titanium oxide is preferably 10 nm to 0.5 μm.
The light extraction portion is not limited to the ink layer, and may be a notch formed on the surface of the light guide, or a rough surface portion formed by sandblasting or the like.

  As shown in FIGS. 15 and 16, the other surface 1b (upper surface or back surface) of the substrate 1 is provided with an electronic component 17 (such as a semiconductor element) for turning on and off the light sources 11 and 13 and adjusting the amount of light. 17a to 17c) are implemented. As the electronic component 17, a publicly known one can be used.

As shown in FIG. 21, the substrate 1 is preferably provided with a touch pad 30 (detection sensor). The touch pad 30 includes an input sensor 31 and a resist layer 32 (covering resin layer) formed on one surface thereof.
The input sensor 31 is a sensor that detects the proximity or contact of a detection target such as a human finger. Here, the input sensor 31 is a capacitance type input sensor, and has a configuration in which the wiring layer 34 is provided on one surface of the base material 33. Since the capacitance type input sensor 31 has a simple structure including a single substrate 33 and a wiring layer 34, it can be thinned.

  The base material 33 is a plate material made of a resin such as PET. The base material 33 may be a flexible substrate made of PEN (polyethylene naphthalate), polyimide, or the like, or a rigid substrate made of glass epoxy resin or the like.

The wiring layer 34 has, for example, a plurality of electrodes 34a. When an object to be detected such as a human finger approaches, an electrostatic capacity is formed between the object to be detected and the electrode 34a, and this capacitance is determined by an opposing area or a separation distance between the object to be detected and the electrode 34a. It depends on. For this reason, the detected object and the electrode 34a form a variable capacitance section.
A change in the capacitance of the variable capacitance unit is detected by a detection means (not shown), and an input operation by the detection target, its position, and the like are grasped by a control unit (not shown) based on the detected value.

The wiring layer 34 can be formed, for example, by heating a silver paste containing silver particles after screen printing on the substrate 33. The wiring layer 34 may be formed by etching a copper foil laminated on the base material 33.
The resist layer 32 secures electrical insulation between the wiring layers 34 and prevents oxidation, and the base material 33 and the wiring layer 34 are formed on one surface (surface on the light guide 12 side) side of the input sensor 31. It is formed to cover. For example, a general-purpose solder resist can be used as the resist layer 32.

As shown in FIGS. 16, 19, and 20, a mask 18 having a light shielding property can be provided on the lower surface side of the range including the first light source 11 and the one end edge 12 a of the light guide 12. The mask 18 in the illustrated example is formed from the first light source 11 to the one end edge 12 a of the light guide 12. The mask 18 is preferably made of a white material.
By providing the mask 18, the light from the first light source 11 can be prevented from leaking to the outside, and the efficiency of introducing the light into the light guide 12 can be increased. Moreover, it can prevent that the brightness | luminance in the 1st light source 11 and its vicinity becomes high locally.

As shown in FIGS. 11 to 15 and FIG. 17, the second illumination unit 3 includes a second light source 13 mounted on one surface 1 a of the substrate 1 and light from the second light source 13 perpendicular to the substrate 1. And an optical path changing unit 14 as second illumination light in a direction inclined with respect to the direction V1.
The 2nd illumination part 3 can be used as a map lamp (spot lamp) which selectively illuminates a narrow range (for example, a driver | operator's or passenger's passenger's hand).

As shown in FIGS. 11, 12, 15, and 17, the second light source 13 is mounted on one surface 1 a of the substrate 1. In this example, two second light sources 13 are provided on the substrate 1 apart from each other.
As the 2nd light source 13, a light emitting diode (henceforth LED) (light emitting element) can be used. The LED is preferably a top view type. The light emitting element used as the second light source 13 may be a cold cathode tube. The number of the second light sources 13 is not limited to the illustrated example, and may be 1 or 3 or more.

As shown in FIG. 12, the light guide 12 has an opening 15 that can accommodate the second light source 13.
The opening 15 in this example is formed so as to gradually increase in diameter from the upper surface 12c toward the lower surface 12d. That is, the inner surface 15b of the peripheral edge portion 15a of the opening 15 is inclined so as to gradually move away from the second light source 13 from the upper surface 12c toward the lower surface 12d.
In the opening 15, the light reflected by the inner surface 15 b of the peripheral edge 15 a travels downward, so that the amount of second illumination light increases.

At least a part of the inner surface 15b of the peripheral edge portion 15a can be a reflecting surface that reflects light from the second light source 13. The entire inner surface 15b is preferably a reflective surface.
The reflective surface of the inner surface 15b is preferably one that can efficiently reflect light from the second light source 13. For example, the inner surface 15b can be made a reflective surface by using a paint (for example, mirror ink) containing metal powder. In order to make the inner surface 15b a reflecting surface, a metal thin film may be formed on the inner surface 15b by a known method.
By using the inner surface 15b as a reflecting surface, the light from the second light source 13 can be efficiently directed to the optical path changing unit 14 to increase the light use efficiency.

At least a part of the inner surface 15b of the peripheral edge portion 15a can also function as a light shielding surface that blocks light from the first light source 11. Accordingly, it is possible to prevent light from the first light source 11 propagating through the light guide 12 from leaking from the inner surface 15b, and it is possible to prevent the use efficiency of light from the first light source 11 from being lowered.
The reflection surface that reflects the light from the second light source 13 also functions as a light shielding surface that blocks the light from the first light source 11. In addition, when a reflecting surface is formed on the inner surface 15b, the light from the first light source 11 is also reflected in the light guide 12, and the utilization efficiency thereof can be increased.

As shown in FIGS. 12 to 14, the optical path changing unit 14 includes a translucent member 20 that transmits light from the second light source 13, a condensing element 21 that narrows an emission range of light that has passed through the translucent member 20, and And a light refraction element 22 that refracts light from the second light source 13.
As shown in FIG. 12, the translucent member 20 is a plate-like body (or a sheet-like body) made of a material having a refractive index greater than 1.
The translucent member 20 in the illustrated example includes a flat plate-like main body portion 20c through which light from the second light source 13 is transmitted and an extending portion 20d extending outwardly from the peripheral edge portion in a flange shape.

The light emitted from the second light source 13 is diffused light having a large divergence angle. However, since the main body portion 20c is located closer to the second light source 13 than the condensing element 21, the wide angle component of the emitted light is also the main body. Incident on the portion 20c. Since the refractive index of the translucent member 20 is greater than 1, the light incident on the translucent member 20 from the surface on the second light source 13 side has a smaller divergence angle than the light before incidence, and the thickness of the translucent member 20 is increased. The light travels by this distance and exits from the surface on the light collecting element 21 side.
Since the divergence angle is suppressed in the translucent member 20, a wide angle component can also be incident on the condensing element 21, so that the light use efficiency can be increased.

  The condensing element 21 may be designed according to the spread angle of the light from the second light source 13 and the inclination angle of the light required for the light emitted from the light refracting unit 22. A part of a curved surface such as an object surface, a cylindrical surface, or an elliptical cylindrical surface may be a main shape, or a shape obtained by combining a plurality of these curved surfaces.

  As shown in FIG. 13, the condensing element 21 in the illustrated example is a Fresnel lens in which a plurality of convex lenses are concentrically combined, and includes a central portion 21a and a first outer peripheral portion 21b formed on the outer peripheral side of the central portion 21a. And a second outer peripheral portion 21c formed on the outer peripheral side of the first outer peripheral portion 21b, and a third outer peripheral portion 21d formed on the outer peripheral side of the second outer peripheral portion 21c. The central portion 21a and the outer peripheral portions 21b to 21d are lenses having a curved surface on the lower surface 21e side.

The outermost peripheral part of the second outer peripheral part 21c is thinner than the innermost peripheral part of the third outer peripheral part 21d, the outermost peripheral part of the first outer peripheral part 21b is thinner than the innermost peripheral part of the second outer peripheral part 21c, and The outermost periphery is thinner than the innermost periphery of the first outer periphery 21b. Due to this structure, the condensing element 21 of this example is thinner than a normal convex lens.
The upper surface 21f of the condensing element 21 is a flat surface along one surface 1a of the substrate 1 and is substantially parallel to the surface 1a (see FIG. 12). For this reason, the condensing element 21 is in a posture along the substrate 1.

  It is preferable that the condensing element 21 can collimate the light that has passed through the translucent member 20. In the example shown in FIGS. 13 and 14, the light L <b> 1 that has passed through the translucent member 20 becomes light L <b> 2 that is parallel light by the light collecting element 21. Note that the condensing element 21 is not necessarily parallelized as long as the light emission range from the second light source 13 can be sufficiently narrowed.

As shown in FIGS. 12 to 14, the optical path changing unit 14 has a structure in which a photorefractive element 22 is provided on the lower surface side of the condensing element 21 (the side opposite to the second light source 13 side).
The photorefractive element 22 refracts light from the second light source 13 and directs it in a direction inclined with respect to the direction V <b> 1 perpendicular to the substrate 1.
In the second illumination unit 3 (3A) located on the left in FIG. 11, the second illumination light LA tilted to the left with respect to the direction V1 is obtained by the photorefractive element 22, and the second illumination unit 3 (on the right) In 3B), the second refracting light LB tilted to the right with respect to the direction V1 is obtained by the photorefractive element 22.
The angles (inclination angle θ shown in FIG. 11) of the second illumination lights LA and LB with respect to the direction V1 perpendicular to the substrate 1 are, for example, 1 ° or more and 45 ° or less.
The inclination angle of the second illumination light is, for example, an angle with respect to the direction V1 of the light traveling direction at the light flux center of the second illumination light.
In FIG. 11 and the like, it is shown that the second illumination lights LA and LB are inclined in the left-right direction, but the inclination direction of the second illumination light is not limited to this, and the second illumination light is in a direction other than the illustrated direction. The photorefractive element 22 can also be installed so that the illumination light is inclined. For example, the second illumination light may be inclined in a direction perpendicular to the paper surface in FIG. 11 (front side or back side with respect to the paper surface).

As shown in FIGS. 13 and 14, the photorefractive element 22 has one or more prism portions 23 that refract light. In the illustrated example, a plurality of prism portions 23 are formed continuously on the upper surface 22 a of the photorefractive element 22. One surface (inner peripheral surface 23a) (see FIG. 14) of the prism portion 23 is inclined with respect to the direction V1.
The inclination direction of the inner peripheral surface 23a is determined according to the required inclination direction of the second illumination light LA. For example, the inner peripheral surface 23a of the prism portion 23 of the second illumination unit 3 (3A) located on the left in FIG. 11 is inclined so as to descend toward the right as shown in FIGS. Yes. The outer peripheral surface 23b of the prism portion 23 can be a surface along the direction V1.
The lower surface 22b of the photorefractive element 22 is a flat surface along one surface 1a of the substrate 1, and is substantially parallel to the surface 1a (see FIG. 12). For this reason, the photorefractive element 22 is in a posture along the substrate 1.

As shown in FIGS. 12, 13, 17, and 18, the condensing element 21 and the light refracting element 22 are fitted into the mounting opening 4 a formed in the lower plate part 4 b of the cover part 4, and the mounting opening 4 a It can fix to the peripheral part.
In this example, the lower surface 22 b of the photorefractive element 22 is flush with the lower surface 4 e (the surface opposite to the second light source 13 side) of the lower plate portion 4 b of the cover portion 4. In the photorefractive element 22, the lower surface 22b may be on the back side (above the lower surface 4e in FIGS. 12 and 13) than the lower surface 4e of the lower plate portion 4b.
The condensing element 21 and the photorefractive element 22 are installed in the attachment opening 4 a of the cover part 4, and thus do not protrude from the cover part 4. For this reason, the condensing element 21 and the photorefractive element 22 are not easily damaged by an external force.
The positional relationship between the condensing element 21 and the light refracting element 22 is not limited to the illustrated example, and the condensing element 21 may be installed on the lower surface side of the light refracting element 22.

As shown in FIGS. 15 and 16, the cover portion 4 covers and protects the substrate 1, the first illumination portion 2, and the second light source 13, and includes a flat plate-like lower plate portion 4 b and its peripheral edge. And a side plate portion 4c formed on the side plate. The cover portion 4 can be attached to the frame portion 5 by locking a locking claw portion 4d formed outward on the side plate portion 4c in the locking hole 5a of the frame portion 5.
The cover portion 4 is preferably made of a transparent material that can transmit light, and is made of, for example, resin or glass.

Next, the illumination light obtained by the 1st illumination part 2 and the 2nd illumination part 3 of the illuminating device 10 is demonstrated.
As shown in FIGS. 16, 17, and 20, in the first illumination unit 2, the light emitted from the first light source 11 (light source 11 a) enters the light guide 12 from the end surface 12 b of the one end edge 12 a, The light propagates through the light guide 12 mainly toward the other end 12f (see FIGS. 16 and 17) while being reflected by the upper surface 12c, the lower surface 12d, and the like.
A part of the light propagating in the light guide 12 is scattered by the light extraction unit 16 and extracted to the lower surface 12d side. Since the light extraction part 16 is formed over the wide range of the upper surface 12c of the light guide 12, the 1st illumination light which is planar light emission is obtained.
The first illumination light illuminates a wide range (for example, the entire interior of the vehicle) where the illumination device 10 is installed. For this reason, the 1st illumination part 2 can be used as a room lamp.

As shown in FIG. 12, in the 2nd illumination part 3, although the light (L21 of FIG. 2) radiate | emitted from the 2nd light source 13 is a diffused light which spreads in an emitted direction, the translucent member 20 is a condensing element. Since it is located closer to the second light source 13 than 21, a wide angle component also enters the main body 20 c.
Since the refractive index of the translucent member 20 is greater than 1, the light incident on the translucent member 20 has a smaller divergence angle than the light before the incidence, proceeds by the thickness of the translucent member 20, and is again spread. Becomes larger and is emitted toward the light collecting element 21.
Since the divergence angle is suppressed in the translucent member 20, a wide angle component can also be incident on the condensing element 21. For this reason, the utilization efficiency of light can be improved.

As shown in FIG. 13, the light L <b> 1 that has passed through the translucent member 20 is narrowed by the condensing element 21. In the illustrated example, the light L2 transmitted through the condensing element 21 is parallel light.
As shown in FIGS. 13 and 14, the light L2 is directed to the light refracting element 22, is incident on the inner peripheral surface 23a that is the inclined surface of the prism portion 23, is transmitted through the light refracting element 22, and is converted into light L3 from the lower surface 22b. Exit. By refraction at the photorefractive element 22, the light L3 is directed in a direction inclined with respect to the direction V1.
The light L3 (second illumination light) selectively illuminates a narrow range (for example, a driver or a passenger in the passenger seat) compared to the first illumination light. For this reason, the 2nd illumination part 3 can be used as a map lamp (spot lamp).

Since the illumination device 10 includes the translucent member 20 that transmits the light from the second light source 13 while suppressing the divergence angle and emits the light toward the condensing element 21, the light from the second light source 13 is converted into a wide-angle component. Can be incident on the light collecting element 21. Accordingly, the light use efficiency can be increased.
Further, since the characteristics of the second irradiation light are determined by the thickness and refractive index of the translucent member 20, the characteristics (spot diameter, etc.) of the second irradiation light can be arbitrarily set by selecting the thickness and material of the translucent member 20. (See FIGS. 4 and 5).
Moreover, since the utilization efficiency of light can be improved without using a reflector, the 2nd light source 13 can be mounted in the board | substrate 1, Therefore The thickness reduction of the illuminating device 10 can be achieved.

As a configuration for adjusting the distance between the light source of the map lamp and the lens in order to optimize the light emission range, as shown in FIG. 22, a moving substrate 111 for mounting a light source that can move with respect to the lens 21 is used. A configuration that is used separately from the above and a configuration that allows the lens 21 to move with respect to the light source 13 as shown in FIG. However, when the moving substrate 111 is used, there is a problem that the internal structure of the apparatus is complicated and the heat dissipation property of the moving substrate 111 is deteriorated. When the lens 21 is movable with respect to the light source 13, the lens 21 is located on the front surface of the apparatus. There is a problem of appearance.
On the other hand, in the illumination device 10, since the light use efficiency can be sufficiently increased, a structure for adjusting the distance between the light source 13 and the condensing element 21 is not necessary, and therefore FIG. 22 and FIG. The above-described problems (complication of internal structure, deterioration of heat dissipation, and deterioration of appearance) do not occur.

Further, in the illuminating device 10, since the optical path changing unit 14 includes the condensing element 21 and the photorefractive element 22, the light whose emission range is sufficiently narrowed by the condensing element 21 can be incident on the photorefractive element 22. . For this reason, the 2nd illumination light inclined by sufficient angle is obtained. As a result, it is not necessary to place the condensing element 21 and the photorefractive element 22 in an inclined manner, so that the apparatus can be reduced in thickness and size.
Moreover, since the condensing element 21 and the photorefractive element 22 can be set in a posture along the substrate 1, the apparatus can have a flat plate structure.
In the lighting device 10, since both the first lighting unit 2 and the second lighting unit 3 are provided on one substrate 1 and the light guide 12 is also provided along the substrate 1, a plurality of substrates is required. Compared with the case where an inclined arrangement of a light guide or the like is required, the apparatus configuration is simple, and from this point, it is suitable for thinning and miniaturization.

Since the lighting device 10 can be manufactured by a simple procedure of providing the light guide 12, the light sources 11, 13 and the like on the one surface 1a side of the substrate 1 on which the electronic component 17 is mounted in advance, it is easy to manufacture and low There is also an advantage that the cost can be reduced.
In addition, since the second illumination unit 3 is provided on the substrate 1, even when a high-power second light source 13 is used, the heat generated by the light source 13 is dispersed throughout the substrate 1 to prevent a local temperature rise and stable. Can be secured.
In particular, since both the first illuminating unit 2 and the second illuminating unit 3 are provided on one substrate 1, even when a high output light source 11 or 13 is used, the heat generated by the light sources 11 and 13 is generated on the substrate 1. It can be dispersed throughout to prevent local temperature rise and ensure stable operation.

  DESCRIPTION OF SYMBOLS 1 ... Board | substrate, 1a ... One surface of a board | substrate, 2 ... 1st illumination part, 3 ... 2nd illumination part 10, 10A, 10B, 10C ... Illumination device, 11 ... -1st light source, 12 ... light guide, 13 ... 2nd light source, 14, 14A, 14B ... optical path changing part, 19 ... movable body, 20, 20B ... translucent member, 20a... One surface, 20b... The other surface, 20c... Main body (light transmitting portion), 20A1 to 20A4 .. translucent member, 21. .. Photorefractive element, 23... Prism portion, 30... Touch pad (detection sensor), L12... First illumination light, L24 and L25. Vertical direction.

Claims (6)

A substrate, a first illumination unit that emits first illumination light, and a second illumination unit that emits second illumination light in a range narrower than the first illumination unit,
The first illumination unit includes a sheet-like light guide along one surface of the substrate, and a first light source that obtains the first illumination light by introducing light into the light guide and propagating the light in the surface direction. Have
The second illumination unit includes a second light source mounted on one surface side of the substrate, and an optical path changing unit that uses the light from the second light source as the second illumination light with a narrow emission range. And
The optical path changing unit includes a translucent member that transmits light from the second light source, and a condensing element that narrows an emission range of light that has passed through the translucent member,
The translucent member is a plate made of a material having a refractive index greater than 1, and the light from the second light source is incident from one surface, transmitted while suppressing a spread angle, and the light is condensed from the other surface. An illumination device that emits light toward an element.   The lighting device according to claim 1, wherein at least a portion through which the light is transmitted has a substantially constant thickness.   The lighting device according to claim 1, wherein the translucent member is substantially parallel to the substrate.   The optical path changing unit includes a photorefractive element having a prism part that refracts light passing through the light condensing element and directs the light in a direction inclined with respect to a direction perpendicular to the substrate. The lighting device according to claim 1. A plurality of the translucent members having different thicknesses and / or refractive indexes, and a movable body provided with the plurality of translucent members,
The movable body is movable with respect to the second light source and the condensing element, and a light transmissive member that transmits light from the second light source by the movement is selected from the plurality of light transmissive members. The lighting device according to any one of claims 1 to 4, wherein the lighting device is possible.   The lighting device according to claim 1, wherein the substrate includes a detection sensor that detects proximity or contact of a detection target.

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