Light-emitting device

Abstract

To suppress the distance between a light source and a light guide member from varying.SOLUTION: A light-emitting device has: a light source which emits light; a light guide member which guides the light; a regulation member which is provided between a mount surface where the light source is placed and a light incidence end surface of the light guide member that the light impinges on, and regulates the distance between the light source and the light guide member; and a retention part which is coupled to a surface of the light guide member which crosses the light incidence end surface, and retains an end part of the light guide member on the side of the light incidence surface. The regulation member includes a first contact part which comes into contact with the mount surface and a second contact part which comes into contact with the retention part.SELECTED DRAWING: Figure 6

Description

[Technical field]

[0001] The present disclosure relates to a light emitting device. [Background technology]

[0002] Light-emitting devices are known that control the light distribution to the walls and floors of a store facility and to signs and other objects installed in the store facility in order to create a spatial effect in the store facility, etc. Also disclosed as a light-emitting device is one that includes a plurality of LED elements and a plurality of rods that guide the light emitted by the LED elements, and in which the emission surfaces of the rods are arranged close to each other, in contact with each other, or integrated together (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2015-088410 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the device of Patent Document 1, the distance between the light source such as an LED element and the light guiding member such as a rod may vary.

[0005] The present disclosure aims to suppress fluctuations in the distance between a light source and a light-guiding member. [Means for solving the problem]

[0006] A light emitting device according to one embodiment of the present disclosure includes a light source that emits light, a light guiding member that guides the light, a defining member that is provided between a mounting surface on which the light source is mounted and a light incident end face of the light guiding member into which the light is incident and defines a distance between the light source and the light guiding member, and a holding portion that is joined to a surface of the light guiding member that intersects with the light incident end face and holds an end of the light guiding member on the light incident end face side, wherein the defining member includes a first contact portion that contacts the mounting surface and a second contact portion that contacts the holding portion. Effect of the Invention

[0007] According to an embodiment of the present disclosure, it is possible to suppress variation in the distance between the light source and the light guiding member. [Brief description of the drawings]

[0008] [Figure 1] 1A and 1B are diagrams showing an example of the overall configuration of a light emitting device according to an embodiment, in which FIG. 1A is a perspective view seen from the light irradiation direction side, and FIG. 1B is a perspective view seen from the opposite side to the light irradiation direction. [Diagram 2] 1 is an exploded perspective view showing an example of the overall configuration of a light emitting device according to an embodiment; [Diagram 3] 11A to 11C are diagrams showing examples of methods for fixing a narrow-angle light-guiding member and a wide-angle light-guiding member to a holder member. [Figure 4] 4 is a plan view of an example of the arrangement of a narrow-angle light-guiding member, a wide-angle light-guiding member, and LEDs according to the embodiment. FIG. [Diagram 5] 4 is an exploded perspective view showing an example of the configuration of the narrow-angle light-guiding member group and its periphery according to the embodiment; FIG. [Figure 6] 4 is a cross-sectional view showing an example of the configuration of the periphery of a narrow-angle light-guiding member group according to the embodiment; FIG. [Figure 7] 7A and 7B are cross-sectional views showing examples of light guiding by a narrow-angle light-guiding member according to an embodiment, where FIG. 7A is a view of a first example and FIG. 7B is a view of a second example. [Figure 8] 1A to 1C are diagrams illustrating an example of light irradiation by a light emitting device according to an embodiment. [Figure 9]9A and 9B are cross-sectional views showing examples of bonding between a narrow-angle light-guiding member and a holder according to modified examples, where FIG. 9A is a view of a first modified example, and FIG. 9B is a view of a second modified example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In the following description, parts having the same reference numerals in multiple drawings indicate the same or equivalent parts or members.

[0010] Furthermore, the embodiments shown below are examples of light-emitting devices for embodying the technical ideas of the present invention, and the present invention is not limited to the embodiments shown below. The dimensions, materials, shapes, relative positions, etc. of the components described below are intended to be illustrative, and not to limit the scope of the present invention, unless otherwise specified. Furthermore, the sizes and positional relationships of the components shown in the drawings may be exaggerated in order to clarify the explanation.

[0011] In the figures shown below, directions may be indicated by the X-axis, Y-axis, and Z-axis, but the X-direction along the X-axis indicates a predetermined direction in an array plane in which multiple light sources provided in the light-emitting device of the embodiment are arranged, the Y-direction along the Y-axis indicates a direction perpendicular to the X-direction in the array plane, and the Z-direction along the Z-axis indicates a direction perpendicular to the array plane.

[0012] Also, the direction in which the arrow points in the X direction is expressed as +X direction, and the opposite direction of the +X direction is expressed as -X direction, the direction in which the arrow points in the Y direction is expressed as +Y direction, and the opposite direction of the +Y direction is expressed as -Y direction, and the direction in which the arrow points in the Z direction is expressed as +Z direction, and the opposite direction of the +Z direction is expressed as -Z direction. In the embodiment, the light emitting device irradiates light in the +Z direction as an example. However, this does not limit the orientation of the light emitting device when it is used, and the orientation of the light emitting device is arbitrary.

[0013] <Configuration of Light-Emitting Device 1> First, the configuration of a light emitting device 1 according to an embodiment will be described.

[0014] (Overall configuration example) Figure 1 is a diagram illustrating an example of the overall configuration of a light-emitting device 1, where Figure 1(a) is an oblique view of the light-emitting device 1 viewed from the light irradiation direction (+Z direction), and Figure 1(b) is an oblique view of the light-emitting device 1 viewed from the -Z direction.

[0015] As shown in FIG. 1(a), the light emitting device 1 has an opening 10 on the front side (+Z direction side) through which light passes, and is formed into a substantially cylindrical shape. As shown in FIG. 1(b), the light emitting device 1 has a connector 21 on the back side (-Z direction side) for electrically connecting to a drive circuit 2. A drive voltage supplied from the drive circuit 2 is applied to a light source housed inside the light emitting device 1 via the connector 21 and an FPC (Flexible Printed Circuits) 22. The light emitting device 1 can irradiate light emitted by application of a drive voltage to the +Z direction side through the opening 10.

[0016] The light emitting device 1 is fixed to, for example, a wall or ceiling of a building and used as a lighting device for illuminating the interior or exterior space of the building. Alternatively, the light emitting device 1 is fixed to a wall or ceiling of a store facility and used as a downlight, spotlight, indirect lighting, etc. for spatial presentation of the store facility. The light emitting device 1 is also mounted on a moving object such as a vehicle and can be used as a headlight for illuminating the surroundings of the moving object.

[0017] Although FIG. 1 illustrates the light emitting device 1 having a substantially cylindrical outer shape, the light emitting device 1 is not limited to this and may be formed into any outer shape, such as a rectangular column.

[0018] Next, Fig. 2 is an exploded perspective view illustrating an example of the overall configuration of the light emitting device 1. As shown in Fig. 2, the light emitting device 1 has a back substrate 11, a heat dissipation member 12, an LED (Light Emitting Diode) mounting substrate 13, a spacer 14, a holder member 15, a narrow-angle light guiding member array 16, and a wide-angle light guiding member array 17.

[0019] The rear substrate 11, heat dissipation member 12, LED mounting board 13, spacer 14 and holder member 15 are stacked in this order along the Z direction, and fixed by screwing a fixing screw 19 into a female threaded hole provided in the holder member 15.

[0020] The narrow-angle light-guiding member array 16 is inserted into the narrow-angle through-hole 151 from the +Z direction side and fixed by fitting, etc., and the wide-angle light-guiding member array 17 is inserted into the wide-angle through-hole 152 from the -Z direction side and fixed by fitting, etc. Note that the fixing is not limited to fitting, and may be performed by adhesive, etc.

[0021] The rear substrate 11 is a plate-like member having a substantially circular outer shape, and is a substrate equipped with wiring on which various electric elements can be mounted. The rear substrate 11 has a connector 21 on the surface on the -Z direction side, and can be connected to the drive circuit 2 via an electric cable or the like. A two-layer printed circuit board with a metal base of, for example, aluminum or copper can be used as the rear substrate 11. Substrates other than a metal base, such as a paper epoxy board or a glass epoxy board, can also be used, but a metal base board is preferable in terms of heat dissipation.

[0022] The heat dissipation member 12 is a columnar member having a substantially circular outer shape. The heat dissipation member 12 is made of a material having good heat dissipation properties, such as aluminum. The heat dissipation member 12 is provided in contact with the LED mounting board 13, and heat generated by driving the LEDs 131 on the LED mounting board 13 is dissipated through the heat dissipation member 12.

[0023] The LED mounting board 13 is a substantially circular plate-like member and is a board provided with wiring on which light sources such as LEDs and various electric elements can be mounted. The material of the LED mounting board 13 is the same as that of the rear board 11, and therefore a duplicated description will be omitted.

[0024] The LED mounting board 13 is electrically connected to the rear substrate 11 via a connector provided on the LED mounting board 13 and the FPC 22. The LED mounting board 13 also includes a plurality of LEDs 131. Note that the LEDs 131 are a collective term for the plurality of LEDs.

[0025] Each LED 131 is an example of a light source that emits light, and is mounted on a mounting surface 132, which is the surface on the +Z direction side of the LED mounting board 13. Each LED 131 is electrically connected to the drive circuit 2 via the LED mounting board 13 and the FPC 22, etc., and emits light in response to a drive voltage applied from the drive circuit 2.

[0026] The LED 131 emits, for example, white light, but is not limited to this, and may emit monochromatic light, and among white light, various colors such as incandescent white, neutral white, and daylight white can be selected.

[0027] For example, NFSWE11A manufactured by Nichia Corporation may be used as the LED 131. In terms of the efficiency of light incidence on the narrow-angle light-guiding member array 16 and the wide-angle light-guiding member array 17, it is preferable to reduce the amount of light traveling from the LED 131 toward the side.

[0028] The spacer 14 is an example of a determining member that is provided between the light incident end face 161i and the light incident end face 171i and the mounting surface 132 on which the LED 131 is placed, and determines the distance between each of the narrow-angle light-guiding member 161 and the wide-angle light-guiding member 171 and the LED 131.

[0029] Here, the light incident end surface 161i is an end surface included in the narrow-angle light-guiding member 161 of the narrow-angle light-guiding member array 16, is disposed opposite the LED 131, and is an end surface through which light emitted by the LED 131 enters the narrow-angle light-guiding member 161. The narrow-angle light-guiding member 161 is a general term for the multiple narrow-angle light-guiding members included in the narrow-angle light-guiding member array 16. The light incident end surface 161i is a general term for each light incident end surface of the multiple narrow-angle light-guiding members 161. The configuration of the narrow-angle light-guiding member 161 will be described separately with reference to FIGS. 5 and 6.

[0030] The light incident end surface 171i is an end surface included in the wide-angle light-guiding member 171 of the wide-angle light-guiding member array 17, is disposed opposite the LED 131, and is an end surface through which light emitted by the LED 131 enters the wide-angle light-guiding member 171. Note that the wide-angle light-guiding member 171 is a general term for multiple wide-angle light-guiding members included in the wide-angle light-guiding member array 17. The light incident end surface 171i is a general term for each light incident end surface of the multiple wide-angle light-guiding members 171.

[0031] The spacer 14 is a substantially circular plate-like member, and is provided with a plurality of spacer through-holes 141, which are rectangular holes, at positions corresponding one-to-one to the plurality of LEDs 131 mounted on the LED mounting substrate 13 when the spacer 14 is overlaid on the LED mounting substrate 13. Note that the spacer through-hole 141 is a general term for the plurality of spacer through-holes.

[0032] The spacer 14 can be manufactured by forming the spacer through-holes 141 in a plate-shaped member by laser processing or the like. There are no particular limitations on the material of the spacer 14, but aluminum is preferable because it has sufficient strength so that the gap does not fluctuate over time and has high heat dissipation properties against heat generated by the LEDs 131. In addition, it is more preferable to subject the spacer 14 to a surface treatment such as blackening in order to reduce flare light or ghost light.

[0033] The -Z direction side of the planar area of ​​the spacer 14 other than the area where the spacer through-holes 141 are formed contacts the surface of the LED mounting board 13 on which the LEDs 131 are placed, and the +Z direction side of the planar area contacts a holding portion 162 included in the narrow-angle light-guiding member array 16. In this state, the back substrate 11, the heat dissipation member 12, the LED mounting board 13, and the spacer 14 are stacked and fixed to the holder member 15. The holding portion 162 is a member that holds each of the narrow-angle light-guiding member 161 and the wide-angle light-guiding member 171, and is a collective term for a plurality of holding portions.

[0034] This defines a predetermined distance between the light emitting surface of the LED 131 and the light incident end surface 161i of the narrow-angle light-guiding member array 16, which face each other across the spacer through-hole 141.

[0035] Furthermore, the rear substrate 11, heat dissipation member 12, LED mounting substrate 13, and spacer 14 are overlapped with positioning pins 18 inserted into positioning through holes provided at predetermined positions of each member. Then, these positioning pins 18 are fitted into positioning recesses provided in holder member 15. As a result, the positions of the rear substrate 11, heat dissipation member 12, LED mounting substrate 13, and spacer 14, and the narrow-angle light-guiding member array 16 and wide-angle light-guiding member array 17 fixed to holder member 15 are aligned in a predetermined state within the respective array planes.

[0036] Holder member 15 is a columnar member having twelve narrow-angle through holes 151 and four wide-angle through holes 152. Narrow-angle light-guiding member 161 is inserted into and fixed in narrow-angle through holes 151, and wide-angle light-guiding member 171 is inserted into and fixed in wide-angle through holes 152. Here, FIG. 3 is a diagram for explaining an example of a method for fixing narrow-angle light-guiding member 161 and wide-angle light-guiding member 171 to holder member 15.

[0037] 3, narrow-angle light-guiding member 161 is inserted into narrow-angle through hole 151 from the +Z direction side along the direction indicated by arrow 31, and after holding portion 162 passes through narrow-angle through hole 151, it is abutted against spacer 14 arranged on the -Z direction side of holder member 15. Thereafter, stopper member 163, which is a sheet metal plate formed into a substantially U-shape, is inserted between holding portion 162 and bottom surface 153 of holder member 15, and narrow-angle light-guiding member 161 is fixed such that holding portion 162 is sandwiched between stopper member 163 and spacer 14.

[0038] On the other hand, the wide-angle light-guiding member 171 is inserted into the wide-angle through hole 152 from the -Z direction side along the direction indicated by the arrow 32, and is fixed by abutting the +Z direction surface of the holding portion 162 against the abutment portion 154 included in the holder member 15.

[0039] 2, the explanation will be continued. Light emitting end face 171o is an end face included in wide-angle light-guiding member 171, and is an end face from which guided light is emitted from inside wide-angle light-guiding member 171 to the outside. Light emitting end face 161o is an end face included in narrow-angle light-guiding member 161, and is an end face from which guided light is emitted from inside narrow-angle light-guiding member 161 to the outside. Note that light emitting end face 171o is a collective notation for the light emitting end faces of each of the multiple wide-angle light-guiding members 171, and light emitting end face 161o is a collective notation for the light emitting end faces of each of the multiple narrow-angle light-guiding members 161.

[0040] The holder member 15 is manufactured by, for example, injection molding a resin material. In order to prevent the light emitted by the LEDs 131 from leaking out of the light emitting device 1 and to prevent visible light such as sunlight from entering the light emitting device 1 from the outside, the resin material of the holder member 15 is preferably not transparent to the light emitted by the LEDs 131 and visible light.

[0041] For example, the resin material may be a thermoplastic resin such as polyphenylene sulfide (PPS) resin, polycarbonate (PC) resin, polymethyl methacrylate (PMMA) resin, acrylonitrile butadiene styrene (ABS) resin, or polyether ether ketone (PEEK) resin. However, the material is not limited to resin, and the holder member 15 may be made of a metal material such as an aluminum alloy.

[0042] The narrow-angle light-guiding member array 16 has 12 narrow-angle light-guiding member groups 16A arranged in a two-dimensional array on the array plane, and each narrow-angle light-guiding member group 16A has nine narrow-angle light-guiding members 161. Therefore, the narrow-angle light-guiding member array 16 has a total of 108 narrow-angle light-guiding members 161. Note that the narrow-angle light-guiding member group 16A is a general term for the 12 narrow-angle light-guiding member groups. The arrangement of the narrow-angle light-guiding members 161 will be described separately with reference to FIG. 4.

[0043] Each narrow-angle light-guiding member 161 has a tapered shape that becomes thinner as it approaches the light incident end face 161i, and a cross section of the narrow-angle light-guiding member 161 that intersects with the light guiding direction is formed into a square shape.

[0044] The tapered shape refers to a shape in which the diameter, width, thickness, or the like of an elongated member tapers down. In this embodiment, as long as the shape becomes thinner toward the light incident end face 161i, it is called a taper even if the inclination of the side surface of each narrow-angle light-guiding member 161 is not symmetrical with respect to the central axis of the narrow-angle light-guiding member 161. In this embodiment, the cross section intersecting the central axis of each narrow-angle light-guiding member 161 is formed in a rectangular shape, but is not limited to a rectangular shape and may be another shape such as a circular shape. This is also true for the wide-angle light-guiding member 171.

[0045] The wide-angle light-guiding member array 17 has four wide-angle light-guiding member groups 17A arranged in an array plane, and each wide-angle light-guiding member group 17A has nine wide-angle light-guiding members 171. Therefore, the wide-angle light-guiding member array 17 has a total of 36 wide-angle light-guiding members 171. Note that the wide-angle light-guiding member group 17A is a general term for the four wide-angle light-guiding member groups. The arrangement of the wide-angle light-guiding members 171 will be described separately with reference to FIG. 4.

[0046] Each wide-angle light-guiding member 171 has a tapered shape that becomes thinner toward the light incident end face 171i, and a cross section of the wide-angle light-guiding member 171 that intersects with the light guiding direction is formed into a square shape.

[0047] Adjacent narrow-angle light-guiding members 161 are connected to each other on the light-emitting end face 161o side. Similarly, adjacent wide-angle light-guiding members 171 are connected to each other on the light-emitting end face 171o side. The 108 light-emitting end faces 161o and the 36 light-emitting end faces 171o are arranged in the arrangement plane and form an opening 10 that functions as an opening through which light in the light-emitting device 1 exits.

[0048] On the light incident end face 161i side of the narrow-angle light-guiding member array 16, adjacent narrow-angle light-guiding members 161 are separated from each other, and the interval between the side faces of adjacent narrow-angle light-guiding members 161 becomes wider as they approach the light incident end face 161i. Similarly, on the light incident end face 171i side of the wide-angle light-guiding member array 17, the interval between the side faces of adjacent wide-angle light-guiding members 171 becomes wider as they approach the light incident end face 171i.

[0049] Here, the narrow-angle light-guiding member 161 and the wide-angle light-guiding member 171 are each an example of a light-guiding member.

[0050] Light emitted by the LED 131 enters the narrow-angle light-guiding member 161 through the light incident end face 161i. The incident light is guided through the narrow-angle light-guiding member 161 while repeatedly undergoing total reflection at the tapered side faces of the narrow-angle light-guiding member 161, and exits through the light exit end face 161o. The taper angle of the narrow-angle light-guiding member 161 is approximately 5.7 degrees, and the spread angle of the exiting light by the narrow-angle light-guiding member 161 is approximately 12.5 degrees. The numerical value of the spread angle indicates the half-value half angle. This also applies hereinafter.

[0051] Furthermore, light emitted by the LED 131 enters the wide-angle light-guiding member 171 through the light incident end face 171i. The incident light is guided through the wide-angle light-guiding member 171 while repeatedly being totally reflected at the tapered side faces of the wide-angle light-guiding member 171, and is emitted through the light exit end face 171o. The taper angle of the wide-angle light-guiding member 171 is approximately 1.9 degrees, and the spread angle of the emitted light by the wide-angle light-guiding member 171 is approximately 30.0 degrees.

[0052] The narrow-angle light-guiding member array 16 is manufactured by injection molding a resin material that is transparent to the light emitted by the LEDs 131, integrating nine narrow-angle light-guiding members 161. Twelve narrow-angle light-guiding member groups 16A, each of which is a set of nine narrow-angle light-guiding members 161, are assembled, and the narrow-angle light-guiding member array 16 is configured by a total of 108 narrow-angle light-guiding members 161. Similarly, the wide-angle light-guiding member array 17 is manufactured by injection molding a resin material that is transparent to the light emitted by the LEDs 131, integrating nine wide-angle light-guiding members 171 for each of four wide-angle light-guiding member groups 17A. Silicone resin, polycarbonate resin, acrylic resin, or the like can be used as the resin material for each of the narrow-angle light-guiding member array 16 and the wide-angle light-guiding member array 17.

[0053] The number or arrangement of the LEDs 131, spacer through holes 141, narrow-angle light-guiding members 161 and wide-angle light-guiding members 171, as well as the external shapes of each member shown in FIG. 2, are merely examples and can be selected as appropriate depending on the purpose of the light-emitting device 1.

[0054] Furthermore, the "wide angle" in the wide-angle light-guiding member array 17 means that the spread angle of the emitted light is relatively wide compared to the narrow-angle light-guiding member array 16, and is not limited to the angle generally called a "wide angle." Similarly, the "narrow angle" in the narrow-angle light-guiding member array 16 means that the spread angle of the emitted light is relatively narrow compared to the wide-angle light-guiding member array 17, and is not limited to the angle generally called a "narrow angle."

[0055] In other words, it is only necessary that the spread angle of the emitted light from the narrow-angle light-guiding member array 16 is narrower than the spread angle of the emitted light from the wide-angle light-guiding member array 17 .

[0056] In addition, the taper angles of the individual light-guiding members in the narrow-angle light-guiding member array 16 and the wide-angle light-guiding member array 17, the number of light-guiding members, and the number of sets of light-guiding members are not limited to those described above, and can be appropriately selected according to the purpose. In addition, in this embodiment, an example is shown in which light is propagated inside the light-guiding member by being totally reflected on the side surface of the light-guiding member, but this is not limited to this. It is also possible to provide a deflecting surface such as a reflecting surface on the side surface of the light-guiding member, so that the light can be deflected by the side surface of the light-guiding member and propagated inside the light-guiding member.

[0057] <Example of Arrangement of Narrow-Angle Light-Guiding Member 161, Wide-Angle Light-Guiding Member 171, and LED 131> Next, Fig. 4 is a plan view illustrating an example of the arrangement of the narrow-angle light-guiding member 161, the wide-angle light-guiding member 171, and the LEDs 131. Fig. 4 shows the light emitting device 1 as viewed from the +Z direction side.

[0058] However, in order to make the arrangement of the narrow-angle light-guiding member 161, the wide-angle light-guiding member 171, and the LEDs 131 easier to understand, Figure 4 only shows the narrow-angle light-guiding member array 16, the wide-angle light-guiding member array 17, and the LED mounting board 13 including the LEDs 131 among the components of the light-emitting device 1.

[0059] As shown in Fig. 4, the narrow-angle light-guiding member array 16 has a total of 12 narrow-angle light-guiding member groups 16A, including two narrow-angle light-guiding members arranged in the Y direction at both ends in the X direction, two narrow-angle light-guiding members arranged in the X direction at both ends in the Y direction, and four narrow-angle light-guiding members arranged in a 2 x 2 arrangement in the center. Each narrow-angle light-guiding member group 16A has nine narrow-angle light-guiding members 161 arranged in a 3 x 3 arrangement. In Fig. 4, the narrow-angle light-guiding members 161 are shown as thin-line rectangles, and the narrow-angle light-guiding member group 16A including the 3 x 3 narrow-angle light-guiding members 161 is shown as a thick-line rectangle.

[0060] Moreover, the wide-angle light-guiding member array 17 has four wide-angle light-guiding member groups 17A surrounding the narrow-angle light-guiding member array 16 from four diagonal directions. Each of the wide-angle light-guiding member groups 17A has nine wide-angle light-guiding members 171 in a 3×3 arrangement. In Fig. 4, the wide-angle light-guiding members 171 are represented by thin-line rectangles that are smaller than the thin-line rectangles representing the narrow-angle light-guiding members 161. Moreover, the wide-angle light-guiding member group 17A including the 3×3 wide-angle light-guiding members 171 is represented by a thick-line rectangle.

[0061] As shown in FIG. 4, each of the narrow-angle light-guiding member 161 and the wide-angle light-guiding member 171 has a square shape in the arrangement plane, and the area of ​​the narrow-angle light-guiding member 161 is larger than the area of ​​the wide-angle light-guiding member 171.

[0062] 4 in one-to-one correspondence with the 108 narrow-angle light-guiding members 161 in total. In the center of each narrow-angle light-guiding member group 16A, the LEDs 131 are arranged so that their centers approximately coincide with the center of the narrow-angle light-guiding member 161, and in the periphery, the LEDs 131 are arranged so that their centers are eccentric with respect to the center of the narrow-angle light-guiding member 161. In the periphery of the narrow-angle light-guiding member group 16A, the LEDs 131 are arranged so that their centers are eccentric with respect to the center of the narrow-angle light-guiding member 161 so that they approach the center of the narrow-angle light-guiding member group 16A.

[0063] For example, the center of the narrow-angle light-guiding member 161c and the center of the LED 131c are substantially aligned with each other. On the other hand, the center of the LED 131f is offset from the center of the narrow-angle light-guiding member 161f so as to approach the center of the narrow-angle light-guiding member group 16A.

[0064] Furthermore, a total of 36 LEDs 131 are provided in one-to-one correspondence with the wide-angle light-guiding members 171. The centers of the wide-angle light-guiding members 171 and the centers of the LEDs 131 corresponding one-to-one to the wide-angle light-guiding members 171 are arranged so as to substantially coincide with each other.

[0065] In the present embodiment, the LED 131 corresponding to the narrow-angle light-guiding member 161 and the LED 131 corresponding to the wide-angle light-guiding member 171 are both LEDs that emit white light, but the present invention is not limited to this. For example, the LED corresponding to the narrow-angle light-guiding member 161 may emit white light, and the LED corresponding to the wide-angle light-guiding member 171 may emit light of a warm white color.

[0066] <Example of the configuration around the narrow-angle light-guiding member group 16A> Next, the configuration of the narrow-angle light-guiding member group 16A will be described with reference to Fig. 5 and Fig. 6. Fig. 5 is an exploded perspective view illustrating an example of the configuration of the narrow-angle light-guiding member group 16A. Fig. 6 is a cross-sectional view illustrating an example of the configuration of the narrow-angle light-guiding member group 16A. Note that Fig. 5 and Fig. 6 show only partial areas of the narrow-angle light-guiding member group 16A, the spacer 14, and the LED mounting board 13 that correspond to the narrow-angle light-guiding member group 16A.

[0067] 5 and 6, the narrow-angle light-guiding member group 16A includes a narrow-angle light-guiding member 161 and a holder 162. The holder 162 is a member that includes a silicone resin containing light-reflective particles and is manufactured by an injection molding method or the like. The holder 162 is a member separate from the narrow-angle light-guiding member array 16.

[0068] The holding portion 162 is joined to a surface of each narrow-angle light-guiding member 161 that intersects with the light incident end surface 161i, and holds an end portion of the narrow-angle light-guiding member 161 on the light incident end surface 161i side. In other words, the surface of each narrow-angle light-guiding member 161 that intersects with the light incident end surface 161i is a tapered surface of the side surface of the narrow-angle light-guiding member 161, and the holding portion 162 holds the vicinity of the end portion of the tapered surface on the light incident end surface 161i side.

[0069] The light-reflective particles are particles that have light reflectivity with respect to the light emitted by the LED 131, and are, for example, white titanium oxide particles, glass beads, calcium carbonate particles, aluminum powder, mica particles, etc. The holding portion 162 contains light-reflective particles and is colored white, etc., so that the light transmittance is low. In contrast, the narrow-angle light-guiding member 161 differs in characteristics in that it does not contain light-reflective particles and has a high light transmittance. However, the holding portion 162 and the narrow-angle light-guiding member 161 can be formed by including the same material (for example, silicone resin, polycarbonate resin, or acrylic resin), and the linear expansion coefficients can be made almost equal, and the deformation amounts associated with temperature changes, etc. are almost equal. The linear expansion coefficient can also be called the linear expansion coefficient, the thermal expansion coefficient, or the thermal expansion coefficient.

[0070] 6, the holding portion 162 is joined to a side surface of the narrow-angle light-guiding member 161 that intersects with the light incident end surface 161i via an adhesive member 20. The adhesive member 20 is made of a resin that contains light-reflective particles and functions as an adhesive. The light-reflective particles are, for example, white titanium oxide particles, glass beads, calcium carbonate particles, aluminum powder, mica particles, etc. Therefore, the adhesive member 20 is colored white or the like and has low light transmittance.

[0071] Although the holding portion 162 has a low light transmittance, since it is joined to the side surface that intersects with the light incident end surface 161i of the narrow-angle light-guiding member 161, it is not obstructed from entering light from the LED 131 through the light incident end surface 161i of the narrow-angle light-guiding member 161.

[0072] The spacer 14 arranged on the -Z direction side of the holding portion 162 contacts the surface of the holding portion 162 on the -Z direction side with the surface 14a on the +Z direction side. The spacer 14 also contacts the mounting surface 132 of the LED mounting board 13 with the back surface 14b on the -Z direction side. In this state, the narrow-angle light-guiding member array 16 including the narrow-angle light-guiding member 161, the spacer 14, and the LED mounting board 13 are fixed to the holder member 15. Here, the front surface 14a of the spacer 14 is an example of a second contact portion that contacts the holding portion 162, and the back surface 14b of the spacer 14 is an example of a first contact portion that contacts the mounting surface 132.

[0073] Since the narrow-angle light-guiding member 161 is joined to the holding portion 162, and the holding portion 162 is in contact with the surface 14a of the spacer 14, even if the narrow-angle light-guiding member 161 expands along the light irradiation direction (Z direction) due to thermal expansion or the like, the movement of the light incident end face 161i toward the LED 131 is suppressed. In other words, the variation in the distance between the light source and the light-guiding member can be suppressed. Note that the narrow-angle light-guiding member 161 thermally expands in the +Z direction with the surface 14a of the spacer 14 as a reference, but in the configuration of FIG. 6, no restricting member such as a glass plate for suppressing thermal expansion is provided on the +Z direction side of the narrow-angle light-guiding member 161, and the light emitting end face 161o is freely movable along the Z direction.

[0074] Furthermore, when the holding portion 162 and the narrow-angle light-guiding member 161 contain the same material, the deformation amounts of the narrow-angle light-guiding member 161 and the holding portion 162 due to temperature changes are approximately equal, so that the difference in the deformation amounts between the two suppresses the shear stress applied to the joint between the narrow-angle light-guiding member 161 and the holding portion 162. As a result, even if the narrow-angle light-guiding member 161 deforms due to temperature changes, damage such as peeling between the narrow-angle light-guiding member 161 and the holding portion 162 is suppressed.

[0075] Furthermore, the narrow-angle light-guiding member 161 has an end portion on the light-emitting end face 161o side that is expandable and contractable in a direction intersecting the light-emitting end face 161o. The direction intersecting the light-emitting end face 161o is, for example, a direction along the Z direction. Therefore, when the narrow-angle light-guiding member 161 expands along the light irradiation direction (Z direction) due to thermal expansion or the like, the light-emitting end face 161o is likely to move in the +Z direction.

[0076] Furthermore, if any of the light emitted by LED 131 propagates toward the side of LED 131, the efficiency of the light entering narrow-angle light-guiding member 161 may decrease; however, holding portion 162 is provided on the side where the radiation angle of the light emitted by LED 131 is large (±90 degrees), and contains light-reflective particles.

[0077] Therefore, by reflecting the light propagating in the direction of the side surface of the LED 131 and guiding it to the light incident end surface 161i, it is possible to suppress a decrease in the efficiency of light incidence into the narrow-angle light-guiding member 161. Here, the propagated light 25 shown in Fig. 6 indicates the light reflected by the holding portion 162 and guided to the light incident end surface 161i.

[0078] In addition, since the adhesive member 20 also contains light-reflective particles, it can reflect light propagating toward the side of the LED 131 and guide it to the light incident end face 161i, thereby suppressing a decrease in the efficiency of light incidence into the narrow-angle light-guiding member 161.

[0079] Although Figures 5 and 6 describe the peripheral configuration of the narrow-angle light-guiding member group 16A, the wide-angle light-guiding member group 17A can also be provided with a holding portion similar to the holding portion 162 and an adhesive member similar to the adhesive member 20, and can obtain the same effect as the holding portion 162 and the adhesive member 20.

[0080] The narrow-angle light-guiding member 161 includes a light incident end face 161ci and a light emitting end face 161co. The narrow-angle light-guiding member 161c is an example of a first light-guiding member. The narrow-angle light-guiding member 161c has a central axis 161cc that passes through both the center of the light incident end face 161ci and the center of the light emitting end face 161co.

[0081] The narrow-angle light-guiding member 161f of the narrow-angle light-guiding member 161 has a light incident end face 161fi and a light emitting end face 161fo. The narrow-angle light-guiding member 161f is an example of a second light-guiding member. The narrow-angle light-guiding member 161f has a central axis 161fc that passes through both the center of the light incident end face 161fi and the center of the light emitting end face 161fo.

[0082] The central axis 161fc is inclined at an inclination angle θ with respect to the Z direction. The central axis 161cc is not inclined with respect to the Z direction. Therefore, the central axis 161fc and the central axis 161cc are inclined at an inclination angle θ.

[0083] Furthermore, the axial distance di is the axial distance between the central axis 161fc and the central axis 161cc on the light incident end face 161i side. The axial distance do is the axial distance between the central axis 161fc and the central axis 161cc on the light emitting end face 161o side. The axial distance do is longer than the axial distance di. In other words, the axial distance between the central axis 161fc and the central axis 161cc is greater on the emission side than on the incidence side.

[0084] With this configuration, the light emitting device 1 having the narrow-angle light-guiding member array 16 can radiate light that changes direction as it travels in the +Z direction. Note that the wide-angle light-guiding member array 17 has a different spread angle of emitted light compared to the narrow-angle light-guiding member array 16, but can radiate divergent light that spreads as it travels in the +Z direction, similar to the narrow-angle light-guiding member array 16.

[0085] <Light Guidance Example Using Narrow-Angle Light-Guiding Member 161> Next, light guiding by the narrow-angle light-guiding member 161 will be described with reference to Fig. 7. Fig. 7 is a cross-sectional view illustrating an example of light guiding by the narrow-angle light-guiding member 161, Fig. 7(a) is a diagram showing a first example, and Fig. 7(b) is a diagram showing a second example.

[0086] As shown in FIG. 7(a), light emitted by the LED 131c enters the narrow-angle light-guiding member 161c through a light incident end face 161ci, is guided within the narrow-angle light-guiding member 161c, and then exits through a light exit end face 161co.

[0087] Illumination light 30c indicated by a dashed line represents light guided within narrow-angle light-guiding member 161c. Illumination light 30c emitted from light emitting end surface 161co illuminates narrow-angle illuminated region 41c on illuminated surface 40. Illuminated surface 40 is, for example, a wall surface inside a room.

[0088] As shown in FIG. 7(b), the light emitted by the LED 131f enters the narrow-angle light-guiding member 161f through the light incident end face 161fi, is guided within the narrow-angle light-guiding member 161f, and then exits through the light exit end face 161fo.

[0089] The irradiation light 30f indicated by the dashed line represents the light guided within the narrow-angle light-guiding member 161f. The irradiation light 30f emitted from the light emitting end face 161fo irradiates the narrow-angle irradiated region 41f on the irradiated surface .

[0090] <Example of light irradiation by light-emitting device 1> Next, light irradiation by the light emitting device 1 will be described with reference to Fig. 8. Fig. 8 is a diagram illustrating an example of light irradiation by the light emitting device 1.

[0091] 8 shows nine narrow-angle irradiated regions 41 and one wide-angle irradiated region 42 on an irradiated surface 40. The nine narrow-angle irradiated regions 41 are regions irradiated with light emitted from each of the nine narrow-angle light-guiding members 161 included in the narrow-angle light-guiding member group 16A of the narrow-angle light-guiding member array 16. In each of the twelve narrow-angle light-guiding member groups 16A, the emitted light from each of the nine narrow-angle light-guiding members 161 irradiates the narrow-angle irradiated region 41, and the twelve irradiated lights overlap at each position of the narrow-angle irradiated region 41.

[0092] Further, one wide-angle illuminated region 42 is an area illuminated with light emitted from each of the 36 wide-angle light-guiding members 171 included in the wide-angle light-guiding member array 17. The emitted light from each of the 36 wide-angle light-guiding members 171 illuminates one wide-angle illuminated region 42, and the 36 illuminated lights overlap in the wide-angle illuminated region 42.

[0093] 8 is merely an example, and the light irradiation pattern by each of the narrow-angle light-guiding member array 16 and the wide-angle light-guiding member array 17 can be appropriately selected depending on the purpose. Furthermore, the light emission of the multiple LEDs 131 can be individually controlled to freely change the light irradiation position, light irradiation direction, light irradiation range, etc. of the light emitting device 1.

[0094] <Effects of Light-Emitting Device 1> As described above, in this embodiment, the distance between the light incident end face 161i and the LED 131 (light source) is determined by the spacer 14 (determining member) provided between the light incident end face 161i of the narrow-angle light-guiding member array 16 and the mounting surface 132 on which the LED 131 (light source) is mounted.

[0095] In addition, a holding portion 162 is provided that is joined to a surface intersecting the light incident end face 161i and holds the end portion of the narrow-angle light-guiding member 161 on the light incident end face 161i side, and the spacer 14 includes a back surface 14b (first contact portion) that contacts the mounting surface 132 and a front surface 14a (second contact portion) that contacts the holding portion 162.

[0096] The narrow-angle light-guiding member 161 is joined to the holding portion 162, and the holding portion 162 is in contact with the surface 14a of the spacer 14. Therefore, even if the narrow-angle light-guiding member 161 expands along the light irradiation direction due to thermal expansion or the like, movement of the light incident end face 161i in the direction approaching the LED 131 is suppressed.

[0097] This makes it possible to suppress fluctuations in the distance between the LED 131 and the narrow-angle light-guiding member 161, and thus to suppress changes in characteristics such as the color of the light emitted by the light emitting device 1.

[0098] Furthermore, since narrow-angle light-guiding member 161 contains a soft silicone resin, the thin portion on the light incident end face 161i side is easily moved by impact or the like. When this thin portion moves, the light guiding state of light guided through narrow-angle light-guiding member 161 may change. Similarly, since wide-angle light-guiding member 171 contains a soft silicone resin, the thin portion on the light incident end face 171i side is easily moved by impact or the like. When this thin portion moves, the light guiding state of light guided through wide-angle light-guiding member 171 may change.

[0099] In this embodiment, the holding portion 162 holds the end portion of the narrow-angle light-guiding member 161 on the light incident end face 161i side, so that it is possible to suppress positional fluctuations in the X, Y, and Z directions of the narrow portion of the narrow-angle light-guiding member 161 on the light incident end face 161i side. Similarly, the holding portion 162 holds the end portion of the wide-angle light-guiding member 171 on the light incident end face 171i side, so that it is possible to suppress positional fluctuations in the X, Y, and Z directions of the narrow portion of the wide-angle light-guiding member 171 on the light incident end face 171i side.

[0100] Furthermore, in this embodiment, narrow-angle light-guiding member 161 and holding portion 162 contain the same material and have approximately the same linear expansion coefficient, so that the amounts of deformation of narrow-angle light-guiding member 161 and holding portion 162 due to temperature changes are approximately the same. This suppresses shear stress applied to the joint between narrow-angle light-guiding member 161 and holding portion 162 due to the difference in the amounts of deformation between the narrow-angle light-guiding member 161 and holding portion 162. Even if narrow-angle light-guiding member 161 deforms due to temperature changes, damage such as peeling between narrow-angle light-guiding member 161 and holding portion 162 can be suppressed.

[0101] In this embodiment, the holder 162 includes a resin containing light-reflective particles, and reflects light emitted by the LED 131 that propagates in a direction in which the radiation angle of the light emitted by the LED 131 is large (±90 degrees) and guides the light to the light incident end surface 161i. This allows the light propagating in that direction to be incident on the narrow-angle light-guiding member 161, and suppresses a decrease in the light incidence efficiency.

[0102] In this embodiment, the narrow-angle light-guiding member 161 can expand and contract in a direction where the end portion on the light-emitting end face 161o side intersects with the light-emitting end face 161o. The direction intersecting with the light-emitting end face 161o is, for example, the light irradiation direction. Therefore, when the narrow-angle light-guiding member 161 expands along the light irradiation direction due to thermal expansion or the like, the light-emitting end face 161o is likely to move in the light irradiation direction. This makes it possible to suppress the movement of the light-incident end face 161i and suppress the variation in the distance between the LED 131 and the narrow-angle light-guiding member 161.

[0103] In this embodiment, the narrow-angle light-guiding member 161 has a tapered shape that becomes thinner as it approaches the light incident end face 161i.

[0104] Furthermore, the narrow-angle light-guiding member 161 includes a narrow-angle light-guiding member 161c (first light-guiding member) and a narrow-angle light-guiding member 161f (second light-guiding member) within an arrangement plane along the light incident end face 161i, and the central axis 161fc of the narrow-angle light-guiding member 161f is inclined with respect to the central axis 161cc of the narrow-angle light-guiding member 161c.

[0105] Moreover, the distance between the central axis 161cc of the narrow-angle light-guiding member 161c and the central axis 161fc of the narrow-angle light-guiding member 161f is greater on the emission side than on the incidence side.

[0106] With these configurations, the light emitted by the light emitting device 1 can be emitted in a desired direction.

[0107] Although the effects of the light emitting device 1 have been described above using the narrow-angle light-guiding member 161 as an example, the wide-angle light-guiding member 171 can also provide similar effects.

[0108] <Modification> In the above-described embodiment, a narrow-angle light-guiding member array 16 in which the holding portion 162 and the narrow-angle light-guiding member 161 are joined by an adhesive member 20 is exemplified, but the joining between the holding portion 162 and the narrow-angle light-guiding member 161 is not limited to this, and various modifications are possible.

[0109] 9A and 9B are cross-sectional views illustrating an example of bonding between a narrow-angle light-guiding member and a holder according to modified examples, where Fig. 9(a) is a diagram showing a first modified example, and Fig. 9(b) is a diagram showing a second modified example.

[0110] 9(a), the narrow-angle light-guiding member array 16a is joined to the narrow-angle light-guiding member 161a and the holder 162a by integral injection molding using a two-color molding method. Here, the two-color molding method refers to a method of molding resins with different properties into one part.

[0111] The holder 162a contains a silicone resin containing light-reflective particles, whereas the narrow-angle light-guiding member 161a contains a silicone resin not containing light-reflective particles.

[0112] The silicone resin of the holding portion 162a contains light-reflecting particles, and therefore the light transmittance of the holding portion 162a is low. On the other hand, the silicone resin of the narrow-angle light-guiding member 161a does not contain light-reflecting particles, and therefore the light transmittance is high. In this respect, the silicone resin of the narrow-angle light-guiding member 161a and the silicone resin of the holding portion 162a are resins with different characteristics.

[0113] Here, when an adhesive member is used to join the narrow-angle light-guiding member 161a and the holding portion 162a, the linear expansion coefficients of the narrow-angle light-guiding member 161a and the holding portion 162a and the adhesive member may differ. Therefore, when the narrow-angle light-guiding member array 16a expands or contracts due to a temperature change or the like, the narrow-angle light-guiding member 161a and the holding portion 162a may expand or contract by different amounts from the adhesive member, causing the narrow-angle light-guiding member 161a and the holding portion 162a to peel off from the adhesive member, and as a result, the narrow-angle light-guiding member 161a may peel off from the holding portion 162a.

[0114] In contrast, in the first modification, the narrow-angle light-guiding member 161a and the holding portion 162a are integrally formed without using an adhesive for joining them, so that separation between the narrow-angle light-guiding member 161a and the holding portion 162a can be prevented.

[0115] The effect of the holding portion 162a containing light reflective particles is similar to that of the holding portion 162.

[0116] 9(b), narrow-angle light-guiding member array 16b is joined to narrow-angle light-guiding member 161b containing silicone resin and holding portion 162b containing metal such as aluminum or stainless steel by integral molding using insert molding. Here, insert molding refers to a method in which resin is injected around a metal part inserted in a molding die, and the resin is molded integrally with the metal part.

[0117] A light emitting device can also be constructed using the narrow-angle light-guiding member array 16b manufactured by such an insert molding method.

[0118] In the above-mentioned modified example, the narrow-angle light-guiding member array has been described, but the same applies to the wide-angle light-guiding member array.

[0119] Although preferred embodiments have been described above in detail, the present invention is not limited to the above-described embodiments, and various modifications and substitutions can be made to the above-described embodiments without departing from the scope of the claims.

[0120] For example, in the above-described embodiment, a light emitting device having a narrow-angle light guiding member array and a wide-angle light guiding member array with different spreading angles of emitted light is exemplified, but the present invention is not limited to this. A light emitting device may be configured using one type of light guiding member array with the same spreading angle of emitted light, or a light guiding member array with three or more types of spreading angles of emitted light. A light emitting device may also be configured using multiple types of light guiding member arrays with different light guiding characteristics other than the spreading angle of emitted light. [Explanation of symbols]

[0121] 1 Light emitting device 10 Opening 11 Rear board 12 Heat dissipation material 13 LED mounting board 131 LED (light source) 132 Placement surface 14 Spacer (an example of a prescribed component) 141 Spacer through hole 15 Holder member 151 Narrow angle through hole 152 Wide angle through hole 16 Narrow-angle light-guiding member array (an example of a light-guiding member) 16A Narrow-angle light-guiding components 161 Narrow angle light guide member 161i Light incidence end face 161o Light output end face 162 Holding part 17 Wide-angle light-guiding member array (an example of a light-guiding member) 17A Wide-angle light-guiding component group 171 Wide-angle light-guiding member 171i Light incidence end face 171o Light output end face 18 Locating pin 19 Fixing screw 2. Drive circuit 20 Adhesive material 21 Connector 22 FPC 25 Propagation of Light 40 Irradiated surface 41 Narrow angle irradiation area 42 Wide-angle illumination area θ Tilt angle di, do Center distance

Claims

1. A light source that emits light; A light guide member that guides the light; a defining member provided between a mounting surface on which the light source is mounted and a light incident end surface of the light guiding member into which the light is incident, the defining member defining a distance between the light source and the light guiding member; a holding portion that is joined to a surface of the light guiding member that intersects with the light incident end surface and holds an end portion of the light guiding member on the light incident end surface side, the defining member includes a first contact portion that contacts the placement surface and a second contact portion that contacts the holding portion, A light emitting device, comprising: a gap provided between the light source and the light incident end surface of the light guiding member.

2. The light emitting device according to claim 1 , wherein the light guide member and the holder include the same material.

3. The light emitting device according to claim 1 , wherein the holding portion includes a resin containing light reflective particles.

4. The light emitting device according to claim 1 , wherein the light guide member and the holding portion are integrally formed.

5. The light emitting device according to claim 1 , wherein the light guide member is extendable and contractible at an end portion thereof on a side of a light emitting end surface from which the light is emitted, the end portion being extendable and contractible in a direction intersecting with the light emitting end surface.

6. The light guide member has a tapered shape that becomes thinner as it approaches the light incident end surface. A light emitting device according to any one of the preceding claims.

7. the light guide member includes a first light guide member and a second light guide member in a plane along the light incident end surface, The light emitting device according to claim 1 , wherein a central axis of the first light guiding member is inclined with respect to a central axis of the second light guiding member.

8. The light emitting device according to claim 7 , wherein an axial distance between a central axis of the first light guiding member and a central axis of the second light guiding member is larger on an emission side than on an incidence side.

Images