JP2016186884A - Transparent material and light emitting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a transparent material which inhibits occurrence of illuminance unevenness in a light emitted thereby.SOLUTION: A transparent material 1 includes: a body part 3. The body part 3 includes: an incidence surface 7 into which light emitted from an LED group 51 may enter; and a first emission surface 9 which faces the incidence surface 7 and emits the light entering into the incidence surface 7. The incidence surface 7 includes a first incidence bending surface 13. The first incidence bending surface 13 curves into a protruding shape so as to separate from the first emission surface 9 and an optical axis AX of the body part 3 passes therethrough. The first emission surface 9 is bent into a recessed shape toward the incidence surface 7.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a light guide and a light emitting device.

  The light emitting device described in Patent Literature 1 includes an LED and a light guide, and realizes light distribution similar to that of an incandescent light bulb. The light guide has a light incident part, a first annular part, a second annular part, and a light emitting part. The light incident part is a conical cutout part. Each of the first annular portion and the second annular portion is a concave portion formed in an annular shape around the optical axis and having a triangular cross section. Light incident from the light incident part, the first annular part, and the second annular part is emitted from the light emitting part.

JP 2012-3845 A

  However, in the light emitting device described in Patent Document 1, each of the light incident portion, the first annular portion, and the second annular portion has a pointed tip. Therefore, the illumination unevenness may occur in the light incident from the light incident part, the first annular part, and the second annular part and emitted from the light emitting part.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a light guide and a light emitting device capable of suppressing the occurrence of uneven illuminance in emitted light.

  The light guide disclosed in the present application includes a main body. The main body includes an incident surface on which light emitted from a light source can be incident, and a first emission surface that faces the incident surface and emits the light incident on the incident surface. The incident surface includes a first incident curved surface. The first incident curved surface is convexly curved away from the first emission surface, and the optical axis of the main body portion passes through. The first exit surface is curved in a concave shape toward the entrance surface.

  In the light guide disclosed in the present application, it is preferable that the first emission surface includes a first emission curved surface through which the optical axis passes and a second emission curved surface formed around the first emission curved surface. The radius of curvature of the second outgoing curved surface is preferably larger than the radius of curvature of the first outgoing curved surface.

  In the light guide disclosed in the present application, it is preferable that the radius of curvature of the first incident curved surface is larger than the radius of curvature of the first outgoing curved surface.

  In the light guide disclosed in the present application, it is preferable that the main body portion further includes a second emission surface that emits the light incident on the incident surface. The second exit surface is preferably formed around the optical axis so as to surround the first exit surface and the entrance surface. Preferably, the incident surface further includes a second incident curved surface formed around the optical axis so as to surround the first incident curved surface. The second incident curved surface is preferably formed such that a distance between the second incident curved surface and the second emission surface increases toward the first emission surface.

  It is preferable that the light guide disclosed in the present application further includes a cylindrical portion. The cylindrical portion is preferably formed along an outer edge of the incident surface and extends along the optical axis. The inner wall surface of the cylindrical portion and the incident surface preferably form a recess.

  In the light guide disclosed in the present application, it is preferable that the cylindrical portion includes a positioning portion that positions the light source with respect to the main body portion.

  In the light guide disclosed in the present application, it is preferable that the cylindrical portion includes a transverse portion where the wiring traverses.

  In the light guide disclosed in the present application, it is preferable that a part or all of at least one of the incident surface, the first emitting surface, and the second emitting surface is subjected to a light diffusion process or a light shielding process.

  A light-emitting device disclosed in the present application includes the light guide and the light source.

  According to the present invention, it is possible to suppress the occurrence of illuminance unevenness in the emitted light.

(A) It is a perspective view which shows the light guide which concerns on embodiment of this invention. (B) It is sectional drawing along the IB-IB line | wire of Fig.1 (a). (A) It is a bottom view which shows the light guide which concerns on embodiment of this invention. (B) It is a top view which shows the light guide which concerns on embodiment of this invention. It is a figure which shows the emission path | route of the light which passes along the light guide which concerns on embodiment of this invention. It is sectional drawing which shows a light-emitting device provided with the light guide which concerns on embodiment of this invention. (A) It is a perspective view which shows the surface side of the light source unit with which the light guide which concerns on embodiment of this invention is mounted | worn. (B) It is a perspective view which shows the back surface side of the light source unit with which the light guide which concerns on embodiment of this invention is mounted | worn. It is a figure which shows a lighting fixture provided with the light guide which concerns on embodiment of this invention. (A) It is a perspective view which shows the light guide which concerns on the modification of embodiment of this invention. (B) It is sectional drawing along the VIIB-VIIB line | wire of Fig.7 (a).

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference numerals and description thereof is not repeated.

  Fig.1 (a) is a perspective view which shows the light guide 1 which concerns on embodiment of this invention. FIG. 1B is a cross-sectional view taken along line IB-IB in FIG. FIG. 2A is a bottom view showing the light guide 1. FIG. 2B is a plan view showing the light guide 1.

  As shown in FIGS. 1A, 1B, 2A, and 2B, the light guide 1 is, for example, a lens. The light guide 1 includes a main body portion 3 and a tube portion 5. The main body 3 has an incident surface 7, a first exit surface 9, and a second exit surface 11. The main body 3 has an optical axis AX.

  The incident surface 7 has a first incident curved surface 13 and a second incident curved surface 15. In FIG. 1B, for easy understanding, the first incident curved surface 13 is surrounded by a broken line, and the second incident curved surface 15 is surrounded by a one-dot chain line. Moreover, in FIG. 2A, in order to distinguish the 1st incident curved surface 13 and the 2nd incident curved surface 15, the dashed-dotted line is attached | subjected.

  The first exit surface 9 has a first exit curved surface 17 and a second exit curved surface 19. In FIG. 1B, for easy understanding, the first outgoing curved surface 17 is surrounded by a broken line, and the second outgoing curved surface 19 is surrounded by a one-dot chain line. Further, in FIG. 2B, in order to distinguish the first outgoing curved surface 17 and the second outgoing curved surface 19, a one-dot chain line is given.

  Light incident from an LED (Light Emitting Diode) group 51 as a light source can be incident on the incident surface 7. The LED group 51 includes a plurality of LEDs. Instead of the LED group 51, a single LED may be used as the light source.

  The optical axis AX of the light guide 1 passes through the center of the first incident curved surface 13. The first entrance curved surface 13 is curved in a convex shape so as to be away from the first exit surface 9. That is, the first incident curved surface 13 is curved in a convex shape toward the LED group 51. The radius of curvature of the first incident curved surface 13 is larger than the radius of curvature of the first outgoing curved surface 17. The first incident curved surface 13 is substantially circular in bottom view as shown in FIG.

  The second incident curved surface 15 is formed around the optical axis AX so as to surround the first incident curved surface 13. The second incident curved surface 15 is substantially annular in bottom view as shown in FIG. The second incident curved surface 15 is formed such that the distance between the second incident curved surface 15 and the second emission surface 11 in the radial direction of the main body 3 increases toward the first emission surface 9. As a result, a substantially annular thick portion 16 is formed around the optical axis AX in the main body 3. Note that the radial direction of the main body 3 is a direction orthogonal to the optical axis AX.

  The first emission surface 9 emits at least a part of the light incident on the incident surface 7. The first exit surface 9 faces the entrance surface 7 and is curved concavely toward the entrance surface 7. Accordingly, the first emission surface 9 forms a recess 27.

  The optical axis AX of the light guide 1 passes through the center of the first outgoing curved surface 17. The first outgoing curved surface 17 is substantially circular in plan view as shown in FIG. The second outgoing curved surface 19 is formed around the first outgoing curved surface 17 and has a substantially annular shape in plan view as shown in FIG. The radius of curvature of the second outgoing curved surface 19 is larger than the radius of curvature of the first outgoing curved surface 17.

  The second emission surface 11 emits at least a part of the light incident on the incident surface 7. The second exit surface 11 is formed around the optical axis AX of the light guide 1 so as to surround the first exit surface 9 and the entrance surface 7. The second emission surface 11 is substantially cylindrical.

  The cylindrical portion 5 is formed along the outer edge of the incident surface 7 and extends along the optical axis AX of the light guide 1. In FIG. 1A, in order to distinguish the main body part 3 and the cylinder part 5, a one-dot chain line is given. The inner wall surface 23 and the incident surface 7 of the cylindrical part 5 form a recess 25. Specifically, the inner wall surface 23 forms the side surface of the recess 25, and the incident surface 7 forms the top surface for the LED group 51. Therefore, the second incident curved surface 15 does not form the side surface of the recess 25. The cylinder portion 5 includes two positioning portions 21 that face each other. The positioning unit 21 positions the LED group 51 with respect to the main body unit 3. In the present embodiment, the positioning portion 21 is a through hole formed in the cylindrical portion 5. The positioning portion 21 may be formed in a concave shape on the inner surface of the cylindrical portion 5 without penetrating the cylindrical portion 5.

  With reference to FIG. 3, the light emission path through the light guide 1 will be described. FIG. 3 is a diagram illustrating an emission path of light passing through the light guide 1. As shown in FIG. 3, the light emitted from the LED group 51 enters the first incident curved surface 13 and enters the main body 3. The first incident curved surface 13 refracts the incident light toward the first emission surface 9. In the present embodiment, the first incident curved surface 13 refracts incident light into parallel light and advances the light toward the first exit surface 9.

  The first emission surface 9 transmits and refracts a part of the light reaching the first emission surface 9 (hereinafter sometimes referred to as “first incident light”). Specifically, the first emission surface 9 transmits and refracts the first incident light at a refraction angle determined by the incident angle of light with respect to the first emission surface 9, the refractive index of the main body 3, and the refractive index of air. And exit.

  Further, the first exit surface 9 is directed toward the second exit surface 11 with another part of the light reaching the first exit surface 9 (hereinafter sometimes referred to as “second incident light”). reflect. Specifically, the first emission surface 9 reflects the second incident light toward the second emission surface 11 at a reflection angle determined by the incident angle of light with respect to the first emission surface 9. In the present embodiment, the first emission surface 9 reflects the second incident light toward the second emission surface 11 so as to be separated from the optical axis AX along the direction D intersecting the optical axis AX.

  The second emission surface 11 transmits and refracts the second incident light and emits it. Specifically, the second exit surface 11 transmits and refracts the second incident light at a refraction angle determined by the incident angle of light with respect to the second exit surface 11, the refractive index of the main body 3, and the refractive index of air. And exit. In the present embodiment, the second emission surface 11 emits the second incident light so as to be separated from the optical axis AX along the direction D intersecting the optical axis AX.

  For example, incident light C <b> 1 out of the light emitted from the LED group 51 enters the first incident curved surface 13 and enters the main body 3. The incident light C <b> 1 indicates light incident on a region near the optical axis AX (hereinafter referred to as “near region”) on the first incident curved surface 13. The first incident curved surface 13 refracts the incident light C <b> 1 toward the first outgoing curved surface 17. The first outgoing curved surface 17 emits a part of the incident light C1 (in the present embodiment, most of the incident light C1) as the outgoing light E1 along the optical axis AX.

  For example, incident light C <b> 2 of the light emitted from the LED group 51 enters the first incident curved surface 13 and enters the main body 3. Incident light C <b> 2 indicates light that has entered a region around the nearby region of the first incident curved surface 13. The first incident curved surface 13 refracts the incident light C <b> 2 toward the second outgoing curved surface 19. The second outgoing curved surface 19 refracts a part of the incident light C2 toward the optical axis AX and emits it as outgoing light E2. The second exit curved surface 19 reflects another part of the incident light C2 toward the second exit surface 11 along the direction D intersecting the optical axis AX. The second emission surface 11 emits the light reflected by the second emission curved surface 19 along the direction D intersecting the optical axis AX as emission light E3.

  In the present embodiment, the direction D intersecting the optical axis AX is a direction orthogonal to the optical axis AX. In FIG. 3, the thick portion 16 is indicated by a region surrounded by a broken line and the second incident curved surface 15, and a hatched line indicating a cross section is omitted for simplification of the drawing.

  With reference to FIG.4 and FIG.5, the light-emitting device 2 provided with the light guide 1 is demonstrated. FIG. 4 is a cross-sectional view showing the light emitting device 2. As shown in FIG. 4, the light emitting device 2 includes a light guide 1 and a light source unit 50. The light source unit 50 includes an LED group 51, a substrate 53, and a socket 55. The LED group 51 is mounted on the substrate 53. The substrate 53 on which the LED group 51 is mounted is attached to the socket 55.

  The light source unit 50 is attached to the recess 25 of the light guide 1. Specifically, the socket 55 includes two claw portions 57 facing each other. And the nail | claw part 57 is engaged with the positioning part 21 formed in the cylinder part 5 of the light guide 1. As shown in FIG. As a result, the light source unit 50 is mounted in the recess 25, and the LED group 51 is positioned with respect to the main body 3 of the light guide 1. Then, the light emitted from the LED group 51 enters the incident surface 7 of the main body 3.

  FIG. 5A is a perspective view showing the surface side of the light source unit 50. FIG. 5B is a perspective view showing the back side of the light source unit 50. As shown in FIGS. 5A and 5B, the light source unit 50 includes two screws 59, two wall portions 63, 2 in addition to the LED group 51, the substrate 53, and the socket 55. One fitting portion 65.

  The socket 55 is formed of an insulator (for example, synthetic resin). A substantially circular hole 60 is formed on the surface of the socket 55. The LED group 51 is exposed from the hole 60. Two screws 59 are arranged so as to sandwich the LED group 51. Screw 59 fixes light source unit 50 to a lighting fixture. In order to increase the creepage distance, an insulating wall 63 is formed between the screw 59 and the LED group 51 in the socket 55. The creepage distance is the shortest distance between two conductive parts (that is, between the screw 59 and the LED group 51) measured along the surface of the insulator.

  The fitting portion 65 is formed on the back surface of the socket 55. Then, the substrate 53 is fitted into the fitting portion 65 and attached to the socket 55. Although not shown for simplification of the drawings, the light source unit 50 further includes two power supply line mounting portions. The power supply line mounting portion is formed on the side wall of the socket 55 and is connected to the LED group 51 via the substrate 53. A power supply line is attached to the power supply line attachment portion. As a result, power is supplied to the LED group 51 from the power line via the substrate 53 and the power line mounting part.

  With reference to FIG. 6, the lighting fixture 100 provided with the light-emitting device 2 is demonstrated. FIG. 6 is a diagram illustrating the lighting apparatus 100. As shown in FIG. 6, the luminaire 100 includes the light emitting device 2. The lighting fixture 100 is suspended from the ceiling 200, for example.

  As described above with reference to FIGS. 1 to 3, according to this embodiment, each of the entrance surface 7 and the first exit surface 9 of the light guide 1 is a curved surface. Therefore, it is possible to suppress the occurrence of illuminance unevenness in the light emitted from the first emission surface 9 as compared with the case where the incident surface and / or the first emission surface has a peak.

  Further, according to the present embodiment, the second exit curved surface 19 transmits and refracts part of the light incident from the first incident curved surface 13 and emits the other part of the light to the optical axis AX. Reflected toward the second exit surface 11 along the intersecting direction D. Accordingly, the light reflected by the second emission curved surface 19 emits light so as to be separated from the optical axis AX along the direction D intersecting the optical axis AX. As a result, the LED group 51 can realize the same light distribution as the light emitted by the filament of the incandescent bulb.

  Further, according to the present embodiment, the radius of curvature of the second outgoing curved surface 19 is larger than the radius of curvature of the first outgoing curved surface 17. Therefore, compared with the case where the radius of curvature of the second exit curved surface is equal to or less than the radius of curvature of the first exit curved surface, the light transmitted and emitted from the second exit curved surface 19 intersects at a position far from the first exit curved surface 17. As a result, it is possible to suppress the occurrence of a dark portion of light on the irradiation surface (for example, the upper surface of the desk top or the floor surface) located on the extension line of the optical axis AX. For example, it is possible to suppress the occurrence of a dark portion in the central region of light that spreads in a circular shape on the irradiation surface.

  Furthermore, according to the present embodiment, the radius of curvature of the first incident curved surface 13 is larger than the radius of curvature of the first outgoing curved surface 17. Therefore, the first incident curved surface 13 can receive more light emitted from the LED group 51 than the case where the curvature radius of the first incident curved surface is equal to or less than the curvature radius of the first outgoing curved surface. That is, the light that does not enter the first incident curved surface 13 among the light emitted from the LED group 51 is lost light, but in the present embodiment, the lost light can be reduced. As a result, the distance between the LED group 51 and the first incident curved surface 13 can be shortened, and consequently the size of the light emitting device 2 can be reduced. Moreover, since loss light can be reduced, the light quantity of the light radiate | emitted from the 2nd output surface 11 can be increased. As a result, the light distribution similar to the light emitted from the filament of the incandescent bulb can be more effectively realized by the LED group 51.

  Furthermore, according to the present embodiment, since the distance between the second incident curved surface 15 and the second emission surface 11 increases toward the first emission surface 9, the thick portion 16 is formed in the main body 3. Is done. Accordingly, the light incident on the second incident curved surface 15 from the LED group 51 is refracted by the second incident curved surface 15 and the second emission surface 11. As a result, it is possible to reduce the light emitted from the second emission surface 11 obliquely downward of the light guide 1 shown in FIG.

  Specifically, as shown in FIG. 3, the light F2 can be suppressed and the refracted light F1 can be increased. As a result, it is possible to suppress a person located obliquely below the light guide 1 from feeling dazzling due to the light emitted from the second emission surface 11. In addition, since the light is refracted by the second incident curved surface 15 and the second outgoing surface 11, it becomes difficult to visually see the inside of the recess 25 from the outside through the second incident curved surface 15 and the second outgoing surface 11. Therefore, it is difficult for a person who is mainly located obliquely below the light guide 1 to visually observe the LED group 51 through the second incident curved surface 15 and the second emission surface 11. As a result, it is possible to improve the aesthetics of the light guide 1 and thus the lighting fixture 100.

  Furthermore, according to this embodiment, the recessed part 25 is formed in the light guide 1 by providing the cylinder part 5. By forming the recess 25, the light source unit 50 can be easily attached to the light guide 1. Further, the claw portion 57 is engaged with the positioning portion 21 and the light source unit 50 is attached to the light guide 1. Therefore, the LED group 51 can be accurately positioned with respect to the main body 3 of the light guide 1. Moreover, since the light-emitting device 2 can be manufactured as one unit, it can be easily developed to various types of lighting fixtures.

(Modification)
With reference to Fig.7 (a) and FIG.7 (b), the light guide 1 which concerns on the modification of embodiment of this invention is demonstrated. The light guide 1 according to this modification is different from the light guide 1 according to the present embodiment that does not have the crossing portion 71 in that the light guide 1 has the crossing portion 71. Hereinafter, the points of the present modification different from the present embodiment will be mainly described.

  Fig.7 (a) is a perspective view which shows the light guide 1 which concerns on this modification. FIG.7 (b) is sectional drawing along the VIIB-VIIB line | wire of Fig.7 (a). As shown in FIGS. 7A and 7B, the cylindrical portion 5 of the light guide 1 further includes two transverse portions 71. In the present modification, the crossing portion 71 is a notch formed in the cylindrical portion 5. The wiring crosses the crossing portion 71. For example, wiring extending from the light source unit 50 attached to the light guide 1 passes through the crossing portion 71 and is drawn out of the light guide 1.

  According to this modification, since the crossing portion 71 is provided, the light guide 1 is prevented from riding on the wiring. As a result, the light guide 1 and the LED group 51 can be arranged on the lighting fixture 100 in an appropriate posture. In addition, in FIG. 7A, in order to distinguish the main-body part 3 and the cylinder part 5, the dashed-dotted line is attached | subjected.

  The embodiments of the present invention have been described above with reference to the drawings. However, the present invention is not limited to the above-described embodiment, and can be implemented in various modes without departing from the gist thereof (for example, (1) to (3) shown below). In addition, various inventions can be formed by appropriately combining a plurality of components disclosed in the above embodiments. For example, some components may be deleted from all the components shown in the embodiment. Furthermore, constituent elements over different embodiments may be appropriately combined. In order to facilitate understanding, the drawings schematically show each component as a main component, and the thickness, length, number, interval, etc. of each component shown in the drawings are actual for convenience of drawing. May be different. In addition, the material, shape, dimensions, and the like of each component shown in the above embodiment are merely examples, and are not particularly limited, and various changes can be made without departing from the effects of the present invention. is there.

  (1) In the present embodiment described with reference to FIGS. 1 to 6 or the present modification described with reference to FIG. 7, of the incident surface 7, the first exit surface 9, and the second exit surface 11. At least one part or all of it may be subjected to light diffusion treatment or light shielding treatment. By the light diffusion process or the light shielding process, the illuminance of the light emitted from the light guide 1 can be reduced, and the glare can be suppressed as necessary. The inner wall surface 23 may or may not be subjected to light diffusion processing, but in the present embodiment, light diffusion processing is not performed as an example. A part or all of the inner wall surface 23 may be light-shielded.

  For example, at least one of a region of the first incident curved surface 13 that faces the first outgoing curved surface 17, a region of the first incident curved surface 13 that faces the second outgoing curved surface 19, and the second incident curved surface 15. On the other hand, a light diffusion process or a light shielding process can be performed. For example, at least one of the first exit curved surface 17, the second exit curved surface 19, and the second exit surface 11 can be subjected to a light diffusion process or a light shielding process. For example, all or part of a region of the first incident curved surface 13 that faces the first outgoing curved surface 17, all or part of a region of the first incident curved surface 13 that faces the second outgoing curved surface 19, second incident curved surface 15 or all of the first exit curved surface 17, all or part of the second exit curved surface 19, or all or part of the second exit surface 11. Can be applied.

  By performing the light diffusion process or the light blocking process on the region of the first incident curved surface 13 that faces the first outgoing curved surface 17, the illuminance directly below the light guide 1 can be reduced. As a result, it can suppress that the person located directly under the light guide 1 feels dazzling. By performing the light diffusing process or the light blocking process on the region of the first incident curved surface 13 that faces the second exit curved surface 19 or the second exit surface 11, the illuminance on the side of the light guide 1 can be lowered. As a result, it can suppress that the person located mainly to the side of the light guide 1 feels dazzling. By performing the light diffusion process or the light blocking process on the second incident curved surface 15, the illuminance of the light guide 1 obliquely below can be lowered. As a result, it can suppress that the person located mainly diagonally downward of the light guide 1 feels dazzling.

  For example, the light diffusion process is performed by roughening the surface of the object, applying a substance that diffuses light to the object, or attaching a film that diffuses light to the object. For example, in the shading process, a paint of a color that does not transmit all or part of the incident light is applied to the object, or a film of a color that does not transmit all or a part of the incident light is applied to the object. Executed by.

  (2) In the present embodiment and this modification, the claw portion 57 formed on the socket 55 is engaged with the positioning portion 21. However, when the light source unit 50 does not have the socket 55, for example, the two claw portions formed on the substrate 53 are engaged with the two positioning portions 21, and the light source unit 50 is attached to the light guide 1. You can also. Moreover, although each of the positioning part 21 and the nail | claw part 57 was provided, it is not limited to two, Three or more may be sufficient. Furthermore, although the two crossing parts 71 were provided, it is not limited to two, One may be sufficient and three or more may be sufficient. Moreover, the positioning part 21 is not limited to a through-hole, For example, a recessed part may be sufficient. Furthermore, the crossing portion 71 is not limited to the notch, and may be a through hole, for example. In addition, in this embodiment, the cylinder part 5 and the positioning part 21 do not need to be provided, and the positioning part 21 does not need to be provided in this modification.

  (3) The lighting fixture which mounts the light guide 1 and the light-emitting device 2 which concern on this embodiment and this modification is not limited to the lighting fixture 100 shown in FIG. For example, the light guide 1 and the light emitting device 2 may be mounted on a lighting fixture that is attached to a vertically standing wall, an inclined wall, or an inclined ceiling. Moreover, the angle which the optical axis AX of the light guide 1 forms with respect to the surface where a lighting fixture is attached may be arbitrary. For example, the light guide 1 can be mounted on the lighting fixture so that the optical axis AX is substantially orthogonal to the surface on which the lighting fixture is mounted, or the optical axis AX is substantially parallel to the surface on which the lighting fixture is mounted. In addition, the light guide 1 can be mounted on the lighting fixture, or the light guide 1 can be mounted on the lighting fixture so that the optical axis AX is inclined with respect to the surface to which the lighting fixture is attached.

  The present invention provides a light guide and a light-emitting device, and has industrial applicability.

DESCRIPTION OF SYMBOLS 1 Light guide 3 Main-body part 5 Cylinder part 7 Incident surface 9 1st output surface 11 2nd output surface 13 1st incident curved surface 15 2nd incident curved surface 17 1st output curved surface 19 2nd output curved surface 21 Positioning part 51 LED group ( light source)
71 Crossing section AX Optical axis

Claims (9)

A light guide including a main body,
The main body is
An incident surface on which light emitted from the light source can be incident;
A first exit surface facing the entrance surface and emitting the light incident on the entrance surface;
The incident surface is
Including a first incident curved surface that is convexly curved away from the first exit surface and through which the optical axis of the body portion passes,
The first light exit surface is a light guide that is curved in a concave shape toward the light entrance surface. The first exit surface includes a first exit curved surface through which the optical axis passes, and a second exit curved surface formed around the first exit curved surface,
The light guide according to claim 1, wherein a radius of curvature of the second outgoing curved surface is larger than a radius of curvature of the first outgoing curved surface.   The light guide according to claim 2, wherein a radius of curvature of the first incident curved surface is larger than the radius of curvature of the first outgoing curved surface. The main body further includes a second emission surface that emits the light incident on the incident surface,
The second exit surface is formed around the optical axis so as to surround the first exit surface and the entrance surface,
The incident surface further includes a second incident curved surface formed around the optical axis so as to surround the first incident curved surface,
4. The method according to claim 1, wherein the second incident curved surface is formed such that a distance between the second incident curved surface and the second emission surface increases toward the first emission surface. 5. Item 1. The light guide according to item 1. A cylindrical portion formed along an outer edge of the incident surface and extending along the optical axis;
The light guide according to any one of claims 1 to 4, wherein an inner wall surface of the cylindrical portion and the incident surface form a recess.   The light guide according to claim 5, wherein the cylindrical part includes a positioning part that positions the light source with respect to the main body part.   The light guide according to claim 5 or 6, wherein the cylindrical portion includes a crossing portion through which the wiring crosses.   The light guide according to any one of claims 1 to 7, wherein a part or all of at least one of the entrance surface and the first exit surface is subjected to a light diffusion process or a light shielding process. The light guide according to any one of claims 1 to 8,
A light emitting device comprising the light source.

Images