Illumination device and inspection apparatus

Abstract

To provide an illumination device and an inspection apparatus that reduce luminance unevenness of the light emitted to an irradiation object.SOLUTION: An illumination device according to an embodiment includes a light source module and a light reflection member. The light source module comprises: a substrate which has a first surface; and multiple light sources which are arranged on the first surface and can emit light that includes first light and second light with the lower luminance than the first light respectively. The light reflection member has a reflective surface that reflects the light emitted by the multiple light sources. The reflective surface includes: a first reflective surface for reflecting the first light; and a second reflective surface for reflecting the second light. The second reflective surface is positioned closer to the substrate side than the first reflective surface. Regarding the light emitted from one of the light sources, the first light reflected by the first reflective surface and the second light reflected by the second reflective surface converge at a focal point.SELECTED DRAWING: Figure 7A

Description

[Technical field]

[0001] The embodiments relate to an illumination device and an inspection device. [Background technology]

[0002] There are illumination devices for shining light onto an object to be irradiated, for example, to observe the surface shape of the object. There are also inspection devices for irradiating an object to be inspected with light from such an illumination device and capturing an image of the object to be inspected (for example, see Patent Document 1).

[0003] In such illumination devices and inspection devices, there is a demand for irradiating an object with light with reduced luminance unevenness in order to observe a clear image. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2012-63245 A Summary of the Invention [Problem to be solved by the invention]

[0005] An object of one embodiment of the present invention is to provide an illumination device and an inspection device that reduce unevenness in luminance of light that illuminates an object to be illuminated. [Means for solving the problem]

[0006] According to one aspect of the present invention, an illumination device includes a substrate having a first surface, a light source module including a plurality of light sources arranged on the first surface and capable of emitting light including a first light and a second light having a lower brightness than the first light, and a light reflecting member having a reflecting surface that reflects the light emitted by each of the plurality of light sources. The reflecting surface includes a first reflecting surface that reflects the first light and a second reflecting surface that reflects the second light. The second reflecting surface is located closer to the substrate than the first reflecting surface. The light emitted from one of the plurality of light sources is focused at a focusing point, with the first light reflected by the first reflecting surface and the second light reflected by the second reflecting surface.

[0007] According to one aspect of the present invention, the lighting device includes a light source module having a substrate having a first surface, a plurality of light sources capable of emitting light, each of which includes a first light and a second light having a lower luminance than the first light, on the first surface, and a plurality of intermediate members including a light reflecting member having a reflecting surface that reflects the light emitted by each of the plurality of light sources. In each of the plurality of intermediate members, the reflecting surface includes a first reflecting surface that reflects the first light and a second reflecting surface that reflects the second light. The second reflecting surface is located closer to the substrate than the first reflecting surface. The light emitted from one of the plurality of light sources is focused at a focusing point, with the first light reflected by the first reflecting surface and the second light reflected by the second reflecting surface. The plurality of light sources are arranged in an arc shape. The plurality of light emitted by the plurality of light sources are reflected by the reflecting surface and travel toward an object to be irradiated. The plurality of intermediate members are connected to each other.

[0008] According to one aspect of the present invention, an inspection apparatus includes an illumination device and an imaging device that is disposed at a distance from the illumination device and captures an inspection object illuminated with the light emitted from the illumination device. The illumination device includes a substrate having a first surface, a light source module having a plurality of light sources arranged on the first surface and capable of emitting light including a first light and a second light having a lower brightness than the first light, and a light reflecting member that reflects the light emitted by each of the plurality of light sources. The reflecting surface includes a first reflecting surface that reflects the first light and a second reflecting surface that reflects the second light. The second reflecting surface is located closer to the substrate than the first reflecting surface. Effect of the Invention

[0009] According to one embodiment of the present invention, it is possible to provide an illumination device and an inspection device that reduce unevenness in luminance of light that illuminates an object to be illuminated. [Brief description of the drawings]

[0010] [Figure 1] 1 is a schematic perspective view illustrating an illumination device according to a first embodiment. [Diagram 2] FIG. 2 is a schematic top view illustrating the lighting device according to the first embodiment. [Figure 3A] 2 is a schematic bottom view illustrating a light source module of the lighting device according to the first embodiment. FIG. [Figure 3B] 2 is a schematic side view illustrating a light source module of the lighting device according to the first embodiment. FIG. [Figure 4A] 2 is a schematic cross-sectional view illustrating a portion of a light source module of the lighting device according to the first embodiment. FIG. [Figure 4B] 2 is a schematic cross-sectional view illustrating a portion of a light source module of the lighting device according to the first embodiment. FIG. [Diagram 5] 3 is a schematic cross-sectional view taken along line VV in FIG. 2. [Figure 6] 3 is a schematic perspective cross-sectional view taken along line VV in FIG. 2. [Figure 7A]FIG. 3 is a schematic cross-sectional view for explaining the operation of the lighting device according to the first embodiment. [Figure 7B] FIG. 7B is a schematic enlarged view of a portion VIIB in FIG. 7A. [Figure 8] FIG. 2 is a schematic diagram for explaining the operation of the lighting device according to the first embodiment. [Figure 9] 5 is a schematic cross-sectional view for explaining the operation of the lighting device according to Reference Example 1. FIG. [Figure 10A] FIG. 4 is a graph obtained by operating the lighting device according to the first embodiment. [Figure 10B] FIG. 11 is a graph obtained by operating the lighting device according to Reference Example 1. [Figure 10C] 1 is a graph collectively showing measurement results of illuminance distribution of the lighting device according to the first embodiment and the lighting device according to reference example 1. FIG. [Figure 11] 13 is a schematic cross-sectional view for explaining the operation of the lighting device according to Reference Example 2. FIG. [Figure 12] 13A and 13B are schematic cross-sectional views for explaining the operation of the lighting device according to Reference Example 3. [Figure 13A] FIG. 12 is a graph obtained by operating the lighting device of FIG. 11. [Figure 13B] FIG. 13 is a graph obtained by operating the lighting device of FIG. 12. [Figure 13C] 13 is a graph collectively showing the measurement results of the illuminance distribution of the illumination device according to the first embodiment, the illumination device in FIG. 11, and the illumination device in FIG. [Figure 14A] FIG. 11 is a schematic perspective view illustrating an illumination device according to a second embodiment. [Figure 14B] 11 is a schematic cross-sectional view illustrating an illumination device according to a second embodiment. FIG. [Figure 15A] FIG. 11 is a schematic perspective view illustrating an illumination device according to a third embodiment. [Figure 15B] 13 is a schematic bottom view illustrating a light source module of the illumination device according to the third embodiment. FIG. [Figure 16A] FIG. 13 is a schematic perspective view illustrating an illumination device according to a fourth embodiment. [Figure 16B] 13 is a schematic bottom view illustrating a light source module of an illumination device according to a fourth embodiment. FIG. [Figure 17A] 13 is a schematic bottom view illustrating a light source module of an illumination device according to a fifth embodiment. FIG. [Figure 17B] 13 is a schematic bottom view illustrating a light source module of an illumination device according to a modified example of the fifth embodiment. FIG. [Figure 17C] 13 is a schematic bottom view illustrating a light source module of an illumination device according to another modified example of the fifth embodiment. FIG. [Figure 18A] 13 is a schematic top view illustrating an illumination device according to a sixth embodiment. FIG. [Figure 18B] FIG. 13 is a schematic perspective view illustrating an illumination device according to a sixth embodiment. [Figure 19A] 13 is a schematic top view illustrating an illumination device according to a modified example of the sixth embodiment. FIG. [Figure 19B] FIG. 23 is a schematic perspective view illustrating an illumination device according to a modified example of the sixth embodiment. [Figure 20A] 13A to 13C are schematic exploded assembly views illustrating a method for manufacturing an illumination device according to a seventh embodiment. [Figure 20B] 13A to 13C are schematic exploded assembly views illustrating a method for manufacturing an illumination device according to a seventh embodiment. [Figure 20C] 13A to 13C are schematic perspective views illustrating a manufacturing method for the lighting device according to the seventh embodiment; [Figure 21] FIG. 13 is a schematic cross-sectional view of a lighting device according to an eighth embodiment. [Figure 22] FIG. 13 is a schematic block diagram illustrating an inspection apparatus according to a ninth embodiment. [Figure 23] FIG. 23 is a schematic block diagram illustrating an inspection device according to a modified example of the ninth embodiment. [Figure 24] FIG. 13 is a schematic cross-sectional view illustrating a part of an inspection device according to another modified example of the ninth embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In addition, the drawings are schematic or conceptual, and the relationship between the thickness and width of each part, the size ratio between parts, etc. are not necessarily the same as those in reality. Even when the same part is shown, the dimensions and ratios of each part may be different depending on the drawing. In this specification and each drawing, elements similar to those described above with reference to the previous drawings are given the same reference numerals and detailed description thereof will be omitted as appropriate.

[0012] (First embodiment) FIG. 1 is a schematic perspective view illustrating the lighting device according to the first embodiment. FIG. 2 is a schematic top view illustrating the lighting device according to the first embodiment. 1, an illumination device 10 according to this embodiment includes a light source module 15 and a light reflecting member 40. The light source module 15 includes a substrate 20 and a plurality of light sources 30. The plurality of light sources 30 are disposed on the substrate 20.

[0013] In order to facilitate understanding of the configuration of the lighting device 10, the following description may be given using a three-dimensional orthogonal coordinate system. The three-dimensional orthogonal coordinate system is assumed to be composed of an X axis, a Y axis, and a Z axis. An XY plane including the X axis and the Y axis is assumed to be parallel to one surface of the substrate 20. The one surface of the substrate 20 is a plane, and is the first surface 21a of the substrate 20, as described later in relation to FIG. 3B. The multiple light sources 30 are assumed to be disposed on the first surface 21a. The Z axis is orthogonal to the XY plane. If the surface of the substrate 20 located opposite the first surface 21a is assumed to be the second surface 21b, the positive direction of the Z axis is the direction from the first surface 21a to the second surface 21b.

[0014] Hereinafter, the case of looking from the positive side of the Z axis to the negative side may be referred to as a top view, and the case of looking from the negative side of the Z axis to the positive side may be referred to as a bottom view. When there is no distinction between a top view and a bottom view, it may be referred to as a planar view. Fig. 1 is a perspective view of the lighting device 10 as seen from the bottom side.

[0015] In the light source module 15, the multiple light sources 30 are arranged in an annular shape in a planar view. In the light source module 15, the optical axis of each of the multiple light sources 30 is parallel to the Z-axis direction, and the multiple light sources 30 emit light downward.

[0016] The light reflecting member 40 is disposed so as to surround the light sources 30 arranged in an annular shape, and is provided so as to cover all of the light sources 30. As will be described later in FIG. 5, the light reflecting member 40 is disposed so as to surround the light sources 30 arranged in an annular shape from the sides and below of the light sources 30. The surface of the light reflecting member 40 facing the light sources 30 is a reflecting surface 42. The reflecting surface 42 reflects the light emitted by each of the light sources 30 inward from the position below the light reflecting member 40 where the light sources 30 arranged in an annular shape are arranged.

[0017] The light emitted from each of the multiple light sources 30 includes light having high luminance and light having low luminance. For example, of the light emitted from each of the multiple light sources 30, the luminance of the light traveling in a direction at a larger angle from the optical axis of the light source 30 is lower than the luminance of the light traveling in a direction at a smaller angle from the optical axis. For example, of the light emitted from each of the multiple light sources 30, the luminance of the light traveling mainly to the side of the light source 30 is lower than the luminance of the light traveling mainly below the light source 30.

[0018] The light reflecting member 40 reflects light having a high luminance among the light emitted from each of the multiple light sources 30 so that the light reaches a position farther from the light source 30 than light having a low luminance. Therefore, light having a high luminance reaches a farther position than light having a low luminance. For example, among the light emitted from each of the multiple light sources 30, light traveling mainly downward from the light source 30 reaches a position farther from the light source 30 than light traveling mainly to the side of the light source 30. Since the luminance of light decreases as the optical path becomes longer, by disposing the irradiation object at an appropriate position below the lighting device 10, it is possible to reduce the unevenness in the luminance of the light irradiating the irradiation object.

[0019] In the illumination device 10, the area surrounded by the multiple light sources 30 arranged in an annular shape is open and is called an opening area WP. The opening area WP is, for example, circular in plan view, and the center of the circular opening area WP is a central axis A1. The central axis A1 is perpendicular to the XY plane and passes through the center of the opening area WP.

[0020] The light emitted from each of the multiple light sources 30 is reflected by the light reflecting member 40 and travels toward the central axis A1 below the light source 30. When an object to be irradiated is placed below the lighting device 10 so as to overlap with the central axis A1 in a plan view, the light emitted from each of the multiple light sources 30 can be observed from above the lighting device 10 through the opening region WP to illuminate the object to be irradiated.

[0021] As shown in FIG. 1 and FIG. 2, the lighting device 10 further includes a housing 50. The housing 50 is a hollow ring-shaped member. The housing 50 houses the light source module 15 and the light reflecting member 40 inside the hollow. The housing 50 has an opening 52A on the inner circumference side. The opening 52A is provided around the inner circumference of the housing 50. The light reflected by the light reflecting member 40 is emitted from the opening 52A to an opening region WP. The housing 50 blocks the light emitted by the light source module 15 and reflected by the light reflecting member 40 in areas other than the opening 52A.

[0022] The configuration of the light source module 15 will now be described in detail. FIG. 3A is a schematic bottom view illustrating the light source module of the lighting device according to the first embodiment. FIG. 3B is a schematic side view illustrating the light source module of the lighting device according to the first embodiment. As shown in Figures 3A and 3B, the light source module 15 has an annular substrate 20 and a plurality of light sources 30 arranged in a ring shape on a first surface 21a of the substrate 20. For example, the substrate 20 has a ring shape centered on a central axis A1. That is, the substrate 20 is a plate-like member partitioned into two concentric circles with the central axis A1 as a common center, and has an outer circular edge 22a and an inner circular edge 22b. The plurality of light sources 30 are arranged in a single circumferential shape between the edges 22a and 22b.

[0023] In this example, the substrate 20 is provided with a plurality of mating holes 24 for coupling with the light reflecting member 40. The mating holes 24 are provided for coupling with the light reflecting member 40. As will be described later in relation to Fig. 5, the mating holes 24 are mated with mating protrusions 40b1 provided on the light reflecting member 40, thereby mating and coupling the substrate 20 and the light reflecting member 40 with each other.

[0024] The substrate 20 is, for example, a printed wiring board. The substrate 20 has a plate-shaped base material formed of insulating resin or the like, and wiring formed of a conductor foil made of a Cu-based alloy or the like on the base material. For example, the substrate 20 is a glass epoxy substrate such as FR-4 or a glass composite substrate such as CEM-3. The substrate 20 is not limited to being made of resin as long as it can provide the first surface 21a as a flat surface on which the multiple light sources 30 are mounted, and may be a metal substrate on which wiring is formed by performing an insulating treatment on the surface. The material of the metal substrate is an alloy containing Al, Cu, or the like. By using the substrate 20 as a metal substrate, a higher heat dissipation effect can be achieved.

[0025] 4A and 4B are schematic cross-sectional views illustrating a part of the lighting device according to the first embodiment. Each of the light sources is, for example, a light emitting device 30a having a light emitting element 31a made of a compound semiconductor. The light emitting device 30a is, for example, a surface mount type light emitting device including a lead 33, a resin molding 34, and the light emitting element 31a.

[0026] In the light emitting device 30a, for example, a pair of plate-like leads 33 are partially embedded in a resin molded body 34. The resin molded body 34 has a recess defined by a bottom surface and a side surface, and the bottom surface defining the recess is constituted by a part of the pair of leads 33, and the side surface has a reflective surface with a predetermined inclination angle.

[0027] The space between the pair of leads 33 is filled with the resin molded body 34, and forms part of the bottom surface of the resin molded body 34. The resin molded body 34 is, for example, rectangular in a plan view. On the bottom surface of the resin molded body 34, part of the pair of leads 33 is exposed as an external terminal portion.

[0028] The base material constituting the lead 33 may be, for example, a plate-like body containing at least one metal selected from copper, aluminum, gold, silver, tungsten, iron, and nickel, or an alloy or clad material such as an iron-nickel alloy or phosphor bronze. A film (for example, a film formed by plating) containing silver, aluminum, gold, or an alloy thereof may be formed on the surface of the lead 33 in order to efficiently extract light from the light-emitting element 31a. The metal film formed on the surface of the lead 33 may be a single-layer film or a multi-layer film.

[0029] The resin molded body 34 may be a resin containing a thermosetting resin or a thermoplastic resin. In particular, it is preferable to use a thermosetting resin. The thermosetting resin is preferably a resin having a lower gas permeability than the resin used for the sealing member 35, and specific examples of the thermosetting resin include epoxy resin, silicone resin, modified epoxy resin such as silicone modified epoxy resin, modified silicone resin such as epoxy modified silicone resin, polyimide resin, modified polyimide resin, urethane resin, modified urethane resin, etc. The resin molded body 34 may contain titanium oxide, aluminum oxide, silicon oxide, etc. as an inorganic filler. By containing an inorganic filler in the resin molded body 34, the light transmittance of the resin molded body 34 can be adjusted.

[0030] The light emitting element 31a is placed on one of a pair of leads 33 that constitute a bottom surface that defines the recess. The light emitting element 31a has a pair of electrodes, and is fixed to the lead 33 by, for example, a bonding member. The light emitting element 31a has a pair of positive and negative electrodes, which are electrically connected to the pair of leads 33 via wires, respectively. The light source can emit light by receiving a supply of electric power from an external source via the pair of leads 33.

[0031] Known light emitting elements 31a can be used. For example, it is preferable to use a light emitting diode as the light emitting element 31a. Any wavelength can be selected for the light emitting element 31a. For example, a semiconductor light emitting element such as a light emitting diode can be used, and the light emitting element 31a capable of emitting visible light such as blue, green, and red can be used. As the blue and green light emitting elements, those using nitride semiconductors such as GaN, InGaN, AlGaN, and AlInGaN can be used. Also, as the red light emitting element, GaAlAs, AlInGaP, and the like can be used. Furthermore, semiconductor light emitting elements made of other materials may be used. The composition, light emitting color, size, number, and the like of the light emitting element used can be appropriately selected according to the purpose. The light emitting element 31a includes a semiconductor laminate, and the semiconductor laminate includes a semiconductor layer including a light emitting layer. Furthermore, a light transmissive substrate such as sapphire may be provided.

[0032] The light emitting element 31a is covered with a light-transmitting sealing member 35. It is preferable to use a resin having excellent heat resistance, weather resistance, and light resistance as the sealing member 35. Examples of such resins include silicone resin, modified silicone resin, epoxy resin, modified epoxy resin, urea resin, phenol resin, acrylic resin, urethane resin, or fluororesin, or a resin containing two or more of these resins.

[0033] In order to provide the sealing member 35 with a predetermined function, at least one selected from the group consisting of inorganic fillers, diffusing agents, pigments, phosphors, and reflective materials can be mixed into the sealing member 35. As the diffusing agent, barium titanate, titanium oxide, aluminum oxide, silicon oxide, and the like can be suitably used. Furthermore, the sealing member 35 may contain organic or inorganic coloring dyes or coloring pigments for the purpose of removing undesired wavelengths. Furthermore, the sealing member 35 may contain, for example, a phosphor.

[0034] When the sealing member 35 contains a phosphor, it functions as a wavelength conversion member. The phosphor to be used is one that can be excited by the light emitted from the light emitting element 31a. For example, phosphors that can be excited by a blue light emitting element or an ultraviolet light emitting element include yttrium aluminum garnet phosphors activated with cerium (YAG:Ce); lutetium aluminum garnet phosphors activated with cerium (LAG:Ce); nitrogen-containing calcium aluminosilicate phosphors activated with europium and / or chromium (CaO-Al2O3-SiO2); silicate phosphors activated with europium ((Sr,Ba)2SiO4); nitride phosphors such as β-sialon phosphors, CASN phosphors, and SCASN phosphors; KSF phosphors (K2SiF6:Mn); sulfide phosphors, quantum dot phosphors, and the like. By combining these phosphors with a blue light emitting element or an ultraviolet light emitting element, light emitting devices of various colors (for example, white light emitting devices) can be manufactured.

[0035] The light source can also be another light emitting device 30b as shown in FIG. 4B. The light emitting device 30b includes, for example, a light emitting element 31b including an electrode 32, a resin molded body 36, and a light transparent member 37. It may further include a light guide member 38 and a metal film 39. The light emitting element 31b includes a pair of electrodes 32.

[0036] (Resin molding 36) The resin molding 36 can be made of, for example, the same material as the resin molding 34 of the light emitting device 30a. (Light-transmitting member 37) The light-transmitting member 37 is a member that covers the light-emitting surface (the other surface opposite to one surface of the semiconductor laminate) of the light-emitting element 31b, and serves as a light extraction surface of the light-emitting device. The light-transmitting member 37 may be made of a light-transmitting resin, glass, or the like. For example, the light-transmitting resin may be made of the same material as the sealing material of the light-emitting device 30a.

[0037] The light transmitting member 37 may contain a phosphor as a wavelength conversion member in addition to the above-mentioned light transmitting material. The phosphor may be the same material as that described for the light emitting device 30a.

[0038] Furthermore, the light-transmitting member 37 may contain an inorganic filler or the like. The light-transmitting member 37 may be formed in a layered form of two or more layers. For example, when the light-transmitting member 37 is formed in two layers, each layer may contain a different phosphor, or only the layer on the light-emitting element side may contain a phosphor. Alternatively, the light-transmitting member 37 may be formed in a three-layered form by combining these.

[0039] The light emitting device 30b may have a light guide member 38 between the light emitting element 31b and the resin molded body 36. The light guide member 38 guides the light emitted from the side surface of the light emitting element 31b to the light transparent member 37.

[0040] The light emitting device 30b may have a metal film 39 on the surface of the electrode 32. The metal film 39 is a film formed mainly to prevent corrosion and oxidation of the surface of the electrode. A material having better corrosion resistance and oxidation resistance than the electrode is selected. For example, the outermost layer is preferably a platinum group metal such as Au or Pt. In addition, when the metal film is to cover the surface of the light emitting device to be soldered, it is preferable to use Au, which has good solderability, for the outermost surface.

[0041] The light emitting device 30a is disposed on the substrate 20 such that the optical axis C1 is perpendicular to the first surface 21a of the substrate 20. That is, the optical axis C1 of the light emitting device 30a is parallel to the Z axis. The optical axis C1 is defined as follows. That is, the optical axis C1 is a straight line connecting points a1 and a2. Point a1 is a plane on the side from which the light emitting device 30a mainly emits light, and is a point where the luminance of the light emitted from the light emitting device 30a is maximum on the first plane P1 parallel to the XY plane. Point a2 is a plane parallel to the XY plane, and is a point where the luminance is maximum within the range irradiated with the light emitted from the light emitting device 30a on the second plane P2 separated from the first plane P1 in the light traveling direction. When there are multiple points where the luminance is maximum on the second plane P2, the center or center of gravity of a figure connecting the multiple existing points may be set to point a2.

[0042] For example, the light emitted by the light emitting device 30a configured as described above may have a Lambertian light distribution. When the light emitting device 30a has a Lambertian light distribution, the luminous intensity in the direction of an angle θ with respect to the optical axis C1 of the light emitting device 30a is multiplied by cosine of the luminous intensity on the optical axis C1. n This means that the light distribution can be approximated by θ times. For example, n is 1 to 11. There are many planes that include the optical axis C1 of the light emitted from the light emitting device 30a, and in each plane, the light distribution pattern of the light emitted from the light emitting device 30a can be said to be a Lambertian light distribution. The definition of the optical axis of the light source 30 is the same as that of the optical axis C1 of the light emitting device 30a, and the optical axis of the light source 30 is also given the same symbol "C1".

[0043] In the lighting device 10 according to the present embodiment, even when the light source 30 emits light having a Lambertian light distribution as described above, the light is reflected in a direction according to the respective luminance, thereby making it possible to reduce uneven luminance of the light illuminating the object to be illuminated.

[0044] A detailed description will be given of the configuration of the light reflecting member 40. Note that a more specific configuration of the light reflecting member 40 will be described later with reference to Figs. 7A and 7B. FIG. 5 is a schematic cross-sectional view taken along line VV in FIG. FIG. 6 is a schematic perspective cross-sectional view taken along line VV in FIG. 5 and 6, the light reflecting member 40 has a reflecting portion 40a and a supporting portion 40b. The light source module 15 is supported by the supporting portion 40b and is coupled to the light reflecting member 40.

[0045] The reflecting portion 40a is a cylindrical member having a length in the Z-axis direction. The diameter of the circle of the reflecting portion 40a in a plan view increases from the bottom to the top. The light source module 15 is disposed above the reflecting portion 40a. The light source module 15 is disposed so that the optical axes of the multiple light sources 30 face downward.

[0046] The reflecting portion 40a has a reflecting surface 42. The reflecting surface 42 is provided on the inner surface of a cylinder forming the reflecting portion 40a. The reflecting surface 42 is provided so as to surround the sides of the multiple light sources 30 and cover the lower sides of the multiple light sources 30. The reflecting surface 42 reflects the light emitted downward from each of the multiple light sources 30 toward the inside of the ring in which the multiple light sources 30 are arranged. In addition, the reflecting surface 42 reflects the light emitted toward the outside of the ring in which the multiple light sources 30 are arranged from each of the multiple light sources 30 toward the inside of the ring in which the multiple light sources 30 are arranged.

[0047] Reflecting surface 42 is a concave surface that is curved in cross section and collects reflected light. The shape of the curved surface of reflecting surface 42 preferably follows an aspheric polynomial including a conic constant k, as described below in relation to Figures 7A and 7B. In the aspheric polynomial that represents the curved surface of reflecting surface 42, the conic constant k is greater than -1 and less than 0.

[0048] Among the light emitted from the light source 30, light having a high brightness that travels downward is reflected at a position on the reflecting surface 42 farther from the substrate 20. The reflected light travels downward from the light source 30 toward the inside of the ring in which the multiple light sources 30 are arranged. Among the light emitted from the light source 30, light having a low brightness that travels toward the outside of the ring in which the multiple light sources 30 are arranged is reflected at a position on the reflecting surface 42 closer to the substrate 20. The reflected light travels downward from the light source 30 toward the inside of the ring. These lights reflected by the reflecting surface 42 are collected at a light collecting point and travel further. By passing through the light collecting point, among the light emitted from the light source 30, light having a high brightness that travels downward reaches a position farther from the reflecting surface 42 having a low brightness that travels toward the outside of the ring. Since light having a high brightness travels a longer optical path to reach the irradiation object than light having a low brightness, it is possible to reduce the brightness unevenness of the light that irradiates the irradiation object.

[0049] The light reflecting member 40 is fixed to the substrate 20 by the support portion 40b. The support portion 40b is provided with, for example, a fitting convex portion 40b1. A plurality of fitting convex portions 40b1 are provided. The plurality of fitting convex portions 40b1 are provided corresponding to the positions of the plurality of fitting holes 24 shown in FIG. 3A in a plan view. The plurality of fitting convex portions 40b1 are fitted into the plurality of fitting holes 24 of the substrate 20, respectively. In this way, the light reflecting member 40 is joined and fixed to the substrate 20.

[0050] The light reflecting member 40 can be made of any material as long as it can be configured to support the substrate 20 and have a stable reflecting surface 42 with a desired curved surface. The reflecting surface 42 is preferably made of a material with low surface roughness, but may be made of a material that diffusely reflects light. For example, the light reflecting member 40 is made of a resin and a metal film provided on the surface of the resin. The metal film provided on the resin surface may be made of a material with high light reflectivity, such as Al or Ag. The light reflecting member 40 itself may be made of a metal containing Al, Ag, or the like.

[0051] When the light reflecting member 40 is formed by integral molding of resin, the mating convex portion 40b1 is inserted into the mating hole portion 24 of the substrate 20, and then the tip of the inserted mating convex portion 40b1 is heat-treated to increase its diameter, thereby joining the substrate 20 and the light reflecting member 40. Note that in Figs. 5 and 6, the mating convex portion 40b1 is shown in a state in which it has an increased diameter after heat treatment.

[0052] The configuration of the housing 50 will be described in detail with reference to FIGS. The housing 50 has an opening 52A and a storage section 52B. The storage section 52B is an annular hollow section that stores the coupled light source module 15 and light reflecting member 40 and fixes them in a predetermined position.

[0053] The opening 52A is provided on the inner edge side of the housing 50. The opening 52A is provided between the first observation opening 52V1 and the second observation opening 52V2. The opening 52A is provided on the inner edge side of the housing 50. The first observation opening 52V1 and the second observation opening 52V2 form a circular space having approximately the same diameter in a plan view. An observer or an imaging device for photographing an object to be irradiated is disposed on the first observation opening 52V1 side. An object to be irradiated is disposed on the second observation opening 52V2 side. The light emitted from the opening 52A is irradiated to the object to be irradiated through the second observation opening 52V2. The illuminated object to be irradiated can be observed through the first observation opening 52V1 and the second observation opening 52V2. That is, the first observation opening 52V1 and the second observation opening 52V2 form the opening area WP described in relation to FIG. 1 and FIG. 2.

[0054] The housing 50 may be made of any appropriate material as long as it has sufficient strength to house the light source module 15 and the light reflecting member 40 and stably fix them in predetermined positions when they are housed inside the housing 50. The housing 50 can be made of a metal such as Al, an alloy such as stainless steel, or a resin.

[0055] The outer surface of the housing 50 is a light absorbing surface 51a that absorbs light. The light absorbing surface 51a may be made of, for example, black resin or the like. The black color is preferably matte. The inner surface of the housing 50 is preferably a light absorbing surface 51b. By making the outer surface of the housing 50 a light absorbing surface 51a, it is possible to prevent reflection of external light, emission of light from the light source module 15, and stray light caused by reflection of light by the light reflecting member 40. In order to prevent light leaking from the light source module 15 or the light reflecting member 40 into the housing 50 from leaking to the outside, it is preferable that the inner surface of the housing 50 is also a light absorbing surface 51b. The outer and inner surfaces may be roughened.

[0056] The operation of the lighting device 10 according to this embodiment will be described. FIG. 7A is a schematic cross-sectional view for explaining the operation of the lighting device according to the first embodiment. FIG. 7B is a schematic enlarged view of portion VIIB in FIG. 7A. 7A and 7B show cross sections of light source module 15 and reflecting portion 40a of the light reflecting member, respectively, for explaining the operation of lighting device 10. FIG.

[0057] 7A and 7B show a part of the lighting device 10 shown in FIG. 5 and the like. In FIG. 7A and 7B, a plurality of light sources 30 are arranged in a ring shape on the substrate 20, and light emitted by one of the plurality of light sources 30 will be described. The plurality of light emitted by the plurality of light sources 30 will be described later in relation to FIG. 8. Also, FIG. 7A shows the positional relationship between the lighting device 10 and the illumination object T1 illuminated by the lighting device 10. Hereinafter, the light emitted by one light source 30 includes a plurality of lights depending on the intensity and direction of the luminance. In FIG. 7A and FIG. 7B, each of the plurality of lights is represented by showing the outermost light ray of the light. The omission of illustrations and the contents of the display of the lights are the same as those described above in FIG. 11 and FIG. 12.

[0058] As shown in Fig. 7A, the irradiation object T1 is disposed so that the center of the irradiation object T1 is substantially aligned with the central axis A1 of the lighting device 10. The shape of the irradiation object T1 in a plan view can be any shape, but for simplicity, in the following description, it is assumed to be a square. In addition, the surface of the irradiation object T1 can be any shape having irregularities, but in the following description, it is assumed to be a flat plane parallel to the XY plane.

[0059] The distance between the lighting device 10 and the irradiation object T1 is set as follows. That is, the distance WD1 is the distance along the Z axis from the end of the reflecting part 40a located opposite to the end on the substrate 20 side to the irradiation object T1. The distance WD0 is a distance for comparison with the lighting device of Reference Example 1 described later in relation to FIG. 9, and is the distance along the Z axis from the end (light extraction surface) of the light source 30 located opposite to the substrate 20 to the irradiation object T1.

[0060] The light L1 emitted by the light source 30 includes light La emitted in the direction of the optical axis C1, and light Lb and Lc emitted at an angle from the optical axis C1. The emission angle of light Lc from the optical axis C1 is larger than the emission angle of light Lb from the optical axis C1. The brightness of light La is higher than that of light Lb, and the brightness of light Lb is higher than that of light Lc. In FIG. 7A and FIG. 7B, light La is represented by a solid line, light Lb is represented by a dashed line, and light Lc is represented by a broken line. In the notation of light La, Lb, and Lc in the figures, the straight lines representing light La, Lb, and Lc represent the ranges of these lights. That is, light La is light within the range of two solid lines bounded by two solid lines, light Lb is light within the range of two dashed lines bounded by two dashed lines, and light Lc is light within the range of two dashed lines bounded by two dashed lines. The notations of the lights La, Lb, and Lc in the figures are the same in FIG. 11 and FIG.

[0061] The reflecting surface 42 has a plurality of reflecting surfaces 42a, 42b, and 42c. The plurality of reflecting surfaces 42a, 42b, and 42c are continuous and form a single smooth reflecting curved surface. The reflecting surface 42c is located closer to the substrate 20 than the reflecting surface 42b in the Z-axis direction. The reflecting surface (second reflecting surface) 42b is located closer to the substrate 20 than the reflecting surface (first reflecting surface) 42a in the Z-axis direction.

[0062] Light (first light) La emitted along the optical axis C1 has the highest brightness and is reflected by the reflecting surface 42a. Light (second light) Lb emitted at an angle from the optical axis C1 has a lower brightness than light La and is reflected by the reflecting surface 42b. Light Lc emitted at a larger angle from the optical axis C1 than light Lb has a lower brightness than light Lb and is reflected by the reflecting surface 42c.

[0063] The light beams La, Lb, and Lc are focused at a focusing point F1 located between the reflecting surface 42 and the irradiation object T1. In the lighting device 10 according to the present embodiment, by appropriately setting the position of the focusing point F1, it is possible to reduce unevenness in the luminance of the light irradiating the irradiation object T1.

[0064] It is possible to set the light-focusing point F1 at an appropriate position by applying an appropriate range of conic constant k to the aspheric polynomial shown in formula (1) to the reflecting surface 42. Here, the appropriate range of conic constant k is greater than -1 and less than 0. In formula (1), the conic constant k is the curvature c, the fourth-order coefficient c4, the sixth-order coefficient c6, and the eighth-order coefficient c8.

[0065]

number

[0066] FIG. 7B shows coordinate axes for applying the aspheric polynomial of formula (1). The y1-axis and z1-axis are set to apply the aspheric polynomial of formula (1) to the light source 30 shown in FIG. 7B. The y1-axis and z1-axis are distinguished from the X-axis, Y-axis, and Z-axis. In the specific example of FIG. 7B, the y1-axis and z1-axis are applied to a plane parallel to the XZ plane. The y1-axis and z1-axis have the center of the end of the light source 30 as their origin. The end of the light source 30 means the surface located on the opposite side of the surface facing the substrate 20. The straight line connecting the origin and the desired focusing point F1 is the z1-axis. The z1-axis is positive in the direction from the origin toward the focusing point F1. The z1-axis is inclined from the optical axis C1 of the light source 30 by an angle φ1. The y1-axis is orthogonal to the z1-axis. The y1-axis is positive in the direction from the origin toward the reflecting surface 42.

[0067] The aspheric polynomial of formula (1) is applied to each light source 30. As described later in relation to Fig. 8, in the illumination device 10, the multiple light sources 30 are arranged in an annular shape and form multiple light focusing points F1. In a specific application to the illumination device 10, a plane that includes the light source 30 and the light focusing point F1 formed by the light source 30 and is parallel to the XY plane is defined, and the aspheric polynomial of formula (1) is applied to each light source 30.

[0068] By setting the cone constant k to be greater than -1 and less than 0, the light La, Lb, and Lc are focused at the focusing point F1. As shown in FIG. 7A, the light La reaches a more distant position on the irradiation object T1 after passing through the focusing point F1. The light Lc reaches a closer position on the irradiation object T1 after passing through the focusing point F1. The light Lb reaches a position between the position on the irradiation object T1 where the light La reaches and the position on the irradiation object T1 where the light Lb reaches after passing through the focusing point F1. Regarding the position where the light La, Lb, and Lc reach the irradiation object T1, the "more distant position" means that the absolute value of the X coordinate is larger on the negative side of the X axis. Regarding the position where the light La, Lb, and Lc reach the irradiation object T1, the "closer position" means that the absolute value of the X coordinate is smaller on the negative side of the X axis.

[0069] The luminance of the light La is higher than that of the light Lb, and the luminance of the light Lb is higher than that of the light Lc. In addition, the optical path of the light La is longer than that of the light Lb, and the optical path of the light Lb is longer than that of the light Lc. The luminance of the light decreases as the optical path becomes longer. The length of the optical path until the light La reaches the position of the irradiation object T1 is longer than the length of the optical path until the light Lb reaches the position of the irradiation object T1. The length of the optical path until the light Lb reaches the position of the irradiation object T1 is longer than the length of the optical path until the light Lc reaches the position of the irradiation object T1. Therefore, by appropriately setting the position where the focal point F1 is formed according to the distance WD1, it is possible to reduce the luminance unevenness of the light irradiating the irradiation object T1 irradiated with the lights La, Lb, and Lc.

[0070] FIG. 8 is a schematic diagram for explaining the operation of the lighting device according to the first embodiment. Fig. 8 is a schematic bottom view of the lighting device 10 when the light reflecting member 40 is disposed in the light source module 15. In order to avoid complexity in the illustration, the following is omitted. That is, the housing 50 is omitted in Fig. 8. Fig. 8 also shows a plurality of light sources 30 arranged in a ring shape, and shows light L1 emitted by some of the light sources 30 and a focal point F1 of the light L1. A curved line connecting a plurality of focal points F1 of the plurality of light beams L1 emitted by the plurality of light sources 30 is shown by a dashed line.

[0071] 8, in the lighting device 10, the light beams L1 emitted by the light sources 30 are each reflected by the light reflecting member 40, and each have a plurality of light focusing points F1. The light beams L1 reflected by the light reflecting member 40 pass through the plurality of light focusing points F1, and then travel toward the irradiation object T1. In this specific example, the light beams L1 are focused at a point where the central axis A1 intersects with the irradiation object T1.

[0072] By arranging the multiple light sources 30 in an annular shape around the central axis A1 so that the multiple emitted lights L1 are directed toward the center, it is possible to reduce uneven brightness of the light irradiating the object T1 to be illuminated.

[0073] In order to more easily understand the operation of the lighting device 10 according to this embodiment, the operation in the case of Reference Example 1 will be described. FIG. 9 is a schematic cross-sectional view for explaining the operation of the lighting device according to the first reference example. In FIG. 9, the light emitted by the light source 30 is represented as a bundle of light rays. The lighting device 110 in Fig. 9 has a light source module 15, but does not have the light reflecting member 40 shown in Fig. 7A. In the example in Fig. 9, the housing is not shown, and only one light source 30 is shown, similar to the case in Fig. 7A. Also, the distance WD0 between the light source 30 and the irradiation target T1 is shown to be the same as the distance WD0 in the case of the lighting device 10 shown in Fig. 7A.

[0074] As shown in Fig. 9, the light source 30 mounted on the substrate 20 emits light having, for example, a Lambertian light distribution. In Fig. 9, the light is represented as a bundle of light rays emitted from the light source 30, and is radiated around the light source 30 according to the light distribution characteristics. For example, the light is also radiated toward the inner edge 22b side of the substrate 20 from the optical axis C1, and is also radiated toward the outer edge 22a side of the substrate 20. Since the irradiation object T1 does not exist on the outer edge 22a side of the substrate 20, the light radiated toward the outer edge 22a side of the substrate 20 does not contribute to the illumination of the irradiation object T1.

[0075] FIG. 10A is a graph obtained by operating the lighting device according to the first embodiment. FIG. 10B is a graph obtained by operating the lighting device according to Reference Example 2. FIG. 10C is a graph collectively showing the measurement results of the illuminance distribution of the lighting device according to the first embodiment and the lighting device according to reference example 2. 10A and 10B are schematic contour diagrams of illuminance when the illumination device 10 according to this embodiment and the illumination device 110 according to reference example 2 respectively illuminate an illumination object T1 located at the same distance WD0. 10C is a graph showing the X-coordinate dependency of the relative illuminance at Y=0 in FIGS. 10A and 10B, with the surface of the irradiation object T1 as the XY plane. D1 represents the measurement result of the lighting device 10, and D2 represents the measurement result of the lighting device 110. The scale on the horizontal axis of FIG. 10C represents the relative coordinate in the X-axis direction, and is a relative value when the length WT1 of the irradiation object T1 in the X-axis direction is set to 1. In each of FIGS. 10A to 10C, the length in the X direction and the length in the Y direction of the irradiation object T1 are indicated as WT1.

[0076] As shown in Fig. 10A and Fig. 10C, in the illumination device 10, the area with a relative illuminance of 100% includes almost the entire area of ​​the illumination object T1. In contrast, as shown in Fig. 10B and Fig. 10C, in the illumination device 110, the area of ​​the illumination object T1 has a relative illuminance lower than 20%, and the area with a relative illuminance of 100% surrounds the outside of the area of ​​the illumination object T1. Furthermore, as shown in Fig. 10C, in the illumination device 110, the area of ​​the illumination object T1 has a relative illuminance lower than 20%, and the inner side is lower. In other words, the illumination device 110 cannot brightly illuminate the illumination object T1, and luminance unevenness occurs.

[0077] 11 and 12 are schematic cross-sectional views for explaining the operation of the lighting device according to the second reference example. In Fig. 11 and Fig. 12, the lighting devices 110a and 110b respectively show cases where the light L1a and L1b reflected by the reflecting surfaces 142a1 and 142a2 of the reflecting parts 140a1 and 140a2 of the light reflecting members are not condensed. Fig. 11 shows an example where the cone constant k=-1 in the aspheric polynomial of formula (1), and the light La, Lb, and Lc emitted from the light source 30 are reflected by the reflecting part 140a1 while spreading, become parallel light, and reach the irradiation object T1. Fig. 12 shows an example where the cone constant k<-1 in the aspheric polynomial of formula (1), and the light La, Lb, and Lc emitted from the light source 30 are reflected by the reflecting part 140a2 while spreading, and reach the irradiation object T1 while continuing to spread.

[0078] As shown in FIG. 11, the light L1a emitted by the light source 30 includes the light La, Lb, and Lc, and the light La, Lb, and Lc are reflected by the reflecting portion 140a1 while spreading in the same manner as in FIG. 7A. The reflected light La, Lb, and Lc all become parallel light and irradiate the irradiation object T1. In the light L1a, as shown in FIG. 13A described later, the area of ​​the irradiation object T1 has a relative illuminance lower than 80%, and the area with a relative illuminance of 100% surrounds the outside of the area of ​​the irradiation object T1. In other words, it can be seen that the luminance unevenness is reduced compared to the case of the illumination device 110 of Reference Example 1 shown in FIG. 10B, but the luminance unevenness is greater than the case of the illumination device 10 of the first embodiment shown in FIG. 10A.

[0079] As shown in FIG. 12, the light L1b emitted by the light source 30 includes the light La, Lb, and Lc, and the light La, Lb, and Lc are reflected by the reflecting surface 142a2 of the reflecting portion 140a2 while spreading in the same manner as in FIG. 7A. The reflected La, Lb, and Lc continue spreading and irradiate the irradiation object T1. In the light L1b, as shown in FIG. 13B described later, the area of ​​the irradiation object T1 has a relative illuminance lower than 80%, and the area with a relative illuminance of 100% surrounds the outside of the area of ​​the irradiation object T1. In other words, it can be seen that the luminance unevenness is reduced compared to the case of the illumination device 110 of Reference Example 1 shown in FIG. 10B, but the luminance unevenness is greater than the case of the illumination device 10 of the first embodiment shown in FIG. 10A.

[0080] FIG. 13A is a graph obtained by operating the lighting device of FIG. FIG. 13B is a graph obtained by operating the lighting device of FIG. FIG. 13C is a graph illustrating the measurement results of the illuminance distribution of the illumination device according to the first embodiment, the illumination device of FIG. 11, and the illumination device of FIG. FIG. 13A is a schematic diagram of the contour of the illuminance of the irradiation object T1 illuminated by the illumination device 110a shown in FIG. 11. FIG. 13B is a schematic diagram of the contour of the illuminance of the irradiation object T1 illuminated by the illumination device 110b shown in FIG. 12. FIG. 13C is a graph showing the X-coordinate dependency of the relative illuminance at Y=0 in FIG. 13A and FIG. 13B, with the surface of the irradiation object T1 as the XY plane. D3 shows the measurement result of the illumination device 110a, and D4 shows the measurement result of the illumination device 110b. For comparison, FIG. 13C also shows the measurement result D1 of the illumination device shown in FIG. 10C.

[0081] As shown in FIGS. 13A and 13C, in the illumination device 110a, a region with a relative illuminance of 100% surrounds the illumination object T1, while near the center of the illumination object T1, the relative illuminance is lower than 80%. As shown in FIGS. 13B and 13C, in the illumination device 110b, an area with a relative illuminance of 100% surrounds the illumination object T1, while the relative illuminance is lower than 80% near the center of the illumination object T1.

[0082] 13C, in the illumination devices 110a and 110b, the relative illuminance of the illumination object T1 changes continuously from about 70% to 100% from the center to the outside of the illumination object T1. Therefore, the surface of the illumination object T1 illuminated by the illumination devices 110a and 110b has luminance unevenness.

[0083] In the illumination device 10 according to this embodiment, the cone constant k is set to a value greater than -1 and less than 0 in the aspheric polynomial shown in formula (1) and other constants are changed, so that the irradiation object T1 can be placed at an arbitrary distance from the illumination device. More specifically, by setting a light collecting point at an appropriate position according to the distance WD1 between the illumination device 10 and the irradiation object T1 and performing an optical simulation or the like, it is possible to set each coefficient and curvature of the aspheric polynomial in formula (1) to an appropriate value.

[0084] The effects of the lighting device 10 according to this embodiment will be described. The lighting device 10 according to this embodiment includes a plurality of light sources 30 arranged on a substrate 20, and a light reflecting member having a reflecting surface 42 that reflects light emitted by each of the plurality of light sources 30. The light L1 emitted by the plurality of light sources 30 is a bundle of a plurality of light beams La, Lb, and Lc having different luminance depending on the direction of emission.

[0085] The angles of the lights La, Lb, and Lc from the optical axis C1 of the light source 30 increase in this order. The luminance of the lights La, Lb, and Lc decreases in this order. In other words, the light source 30 emits light L1 with a lower luminance as the angle from the optical axis C1 increases.

[0086] The reflecting surface 42 of the light reflecting member 40 has reflecting surfaces 42a, 42b, and 42c, which are continuous curved surfaces. The reflecting surfaces 42a, 42b, and 42c are located away from the substrate 20 in this order. The light La is reflected by the reflecting surface 42a, the light Lb is reflected by the reflecting surface 42b, and the light Lc is reflected by the reflecting surface 42c. The lights La, Lb, and Lc reflected by the reflecting surfaces 42a, 42b, and 42c are focused at a focusing point F1.

[0087] Since the light focusing point F1 is formed between the irradiation object T1 and the reflecting surface 42, the light La reaches a position on the irradiation object T1 that is farther from the reflecting surface 42. Furthermore, the light Lb reaches a position on the reflecting surface 42 that is closer to the reflecting surface 42 than the position on the irradiation object T1 where the light La reaches, and the light Lc reaches a position on the reflecting surface 42 that is closer to the reflecting surface 42 than the position on the irradiation object T1 where the light Lb reaches. Therefore, the irradiation object T1 can be illuminated with light with reduced luminance unevenness.

[0088] The lighting device 10 according to this embodiment includes a light reflecting member, and can reflect the light L1 emitted from each of the multiple light sources 30 in a desired direction. It is not necessary to change the optical axis C1 of each of the multiple light sources 30 according to the distance to the irradiation object T1, and the optical axis C1 can be in the same direction.

[0089] The optical axis C1 of the light source 30 can be set so as to be perpendicular to the first surface 21a of the substrate 20, which is the mounting surface of the light source 30. Therefore, a general-purpose rigid substrate such as FR-4 or CEM-3 can be used, and the light source module 15 can be formed at low cost.

[0090] Conventionally, as a light source of a ring-shaped illumination device, for example, there is Patent Document 1. In such a conventional illumination device, there is a concern that problems may occur in the wiring formed on the substrate by bending the substrate, and in the connection reliability of the light-emitting device connected to the wiring. In addition, since the optical axis of the light-emitting device is set by bending the substrate, it is necessary to reset the degree of curvature of the substrate when changing the inclination of the optical axis according to the distance from the irradiation object. Furthermore, when the light-emitting device is mounted on a flexible substrate, it is often difficult to efficiently dissipate heat from the light-emitting device, and it is difficult to realize an illumination device that can irradiate the irradiation object with high brightness.

[0091] In the lighting device 10 according to the present embodiment configured as described above, it is sufficient to arrange a plurality of light sources with their optical axes aligned on a general-purpose rigid board, and therefore there is no need to make any mechanical changes to the board 20. Therefore, since no mechanical stress is applied to the board 20 after the light sources 30 are mounted on the board 20, high connection reliability between the light sources 30 and the wiring of the board 20 can be easily achieved.

[0092] When changing the distance between the lighting device and the object T1 to be irradiated, the distance can be easily changed by appropriately setting the reflecting surface of the light reflecting member. Even when changing the light reflecting member according to the distance, the light source module 15 can be made common. Therefore, it is possible to quickly provide a lighting device according to the distance.

[0093] As described above, in the lighting device 10 according to the present embodiment, the light source module 15 can be configured using a general-purpose rigid substrate. Therefore, the optical axis C1 of the light source 30 can be in the same direction. Therefore, the light emitting devices 30a and 30b having the surface mount type package shown in FIG. 4A and FIG. 4B can be used as the light source. When the light emitting devices 30a and 30b having the surface mount type package are used as the light source, the leads 33 and the electrodes 32 having a wide area can be arranged over the mounting surface and connected to the wiring on the substrate 20 side. The thermal resistance between the light emitting elements 31a and 31b and the substrate 20 can be reduced, and the heat of the light emitting devices 30a and 30b can be efficiently dissipated through the substrate 20. Therefore, it is easy to increase the brightness of the lighting device 10. In addition, by using the light emitting devices 30a and 30b having the surface mount type package as the light source, it is possible to reduce the height of the light source module 15 and to reduce the thickness of the lighting device 10.

[0094] As described above in relation to FIG. 4A, the light emitted by the light emitting device 30a may have a Lambertian light distribution, and other light sources 30 may also have a Lambertian light distribution. Light having a Lambertian light distribution has a wider directivity than conventional lighting devices. In the lighting device 10, even light having a large angle from the optical axis C1 of the light source 30 can be reflected by the reflecting surfaces 42b and 42c of the light reflecting member 40 and emitted toward the irradiation target T1. The reflecting surfaces 42b and 42c are located closer to the light source module 15 than the reflecting surface 42a that reflects light in the direction of the optical axis C1 and having a small angle from the optical axis C1. In the lighting device 10, the light La reflected by the reflecting surface 42a and the light Lb and Lc reflected by the reflecting surfaces 42b and 42c, respectively, are focused at a focusing point F1. Therefore, light La having a high brightness can reach a position farther away on the irradiation object T1 than light Lb, Lc having a low brightness, thereby reducing uneven brightness of the light irradiating the irradiation object T1.

[0095] In the lighting device 10, the light sources 30 are arranged in a circular ring shape centered on the central axis A1 in a plane parallel to the XY plane. The light beams emitted from the light sources 30 are reflected by the reflecting surface 42, and are focused on the light focusing points F1, and then travel toward the central axis A1. Therefore, the light focusing points F1 are formed in a circular shape centered on the central axis A1. By placing the irradiation object T1 at a position including the central axis A1 on a plane parallel to the XY plane, the light beams emitted by the light sources 30 can illuminate the irradiation object T1 with sufficient brightness.

[0096] It is known that chromatic aberration occurs when a lens is disposed anywhere in the optical path of light emitted from a light source. When the light source emits white light, the white light contains light of many colors, and large color shift occurs due to chromatic aberration caused by the lens. In the illumination device 10 according to this embodiment, no lens is disposed in the optical path along which the light emitted from the light source 30 travels. Therefore, chromatic aberration caused by the lens does not occur, and light with reduced color unevenness can be irradiated onto the illumination object.

[0097] In the above-mentioned specific example, the light sources 30 are arranged in a circular ring shape, but the light sources 30 may be arranged in an elliptical ring shape or a polygonal ring shape depending on the light distribution pattern of each of the light sources 30, the intensity of the luminance, the shape of the object to be irradiated, and the like. In order to obtain the same effect as described above, the light sources 30 are not necessarily arranged stationary. For example, one light source 30 may be rotated in a ring shape within a plane parallel to the XY plane. Also, a light source in which the light sources 30 are arranged in a line may be rotated in a ring shape within a plane parallel to the XY plane.

[0098] Second Embodiment FIG. 14A is a schematic perspective view illustrating the illumination device according to the second embodiment. FIG. 14B is a schematic cross-sectional view illustrating the lighting device according to the second embodiment. 14A and 14B, an illumination device 210 according to this embodiment differs from the illumination device 10 shown in FIG. 1 in that the illumination device 210 includes a housing 250 including a light-transmitting member 254. In other respects, the configuration of the illumination device 210 is the same as that of the illumination device 10 according to the first embodiment. The same components are denoted by the same reference numerals, and detailed descriptions thereof will be omitted as appropriate.

[0099] The housing 250 has a light-transmitting member 254, an opening 52A, a storage section 52B, a first observation port 52V1, and a second observation port 52V2. The housing 250 is a hollow annular member, and the opening 52A, the storage section 52B, the first observation port 52V1, and the second observation port 52V2 are similar to the housing 50 shown in FIG.

[0100] The light-transmitting member 254 covers the opening 52 A. The plurality of light beams emitted from the light source module 15 and reflected by the reflecting surface 42 of the light reflecting member 40 are emitted via the light-transmitting member 254 to the opening region WP.

[0101] The light-transmitting member 254 is formed of a material having light-transmitting properties, for example, a transparent resin. The light-transmitting member 254 is provided to prevent foreign matter such as dust from entering through the opening 52A. The light-transmitting member 254 may be formed of a transparent resin having sufficient transparency, or may be formed of a light-transmitting resin in which a scattering filler is dispersed. When the light-transmitting member 254 is made of a light-transmitting resin in which a diffusing filler is dispersed, the light emitted from the light-transmitting member 254 is diffused, so that when the light reaches an object to be irradiated, the object can be irradiated with light having a further reduced brightness. In this case, it is preferable that the light emitted from the light-transmitting member 254 is limited to a degree of diffusion that causes the light to be condensed at the condensing point F1, as described in relation to FIG. 7A.

[0102] The effects of the illumination device 210 according to this embodiment will be described. The lighting device 210 according to this embodiment has the same effects as the lighting device 10 shown in Fig. 1 etc. In addition, it has the following effects. That is, since the lighting device 210 includes the housing 250 that covers the opening 52A with the light-transmitting member 254, the inside of the lighting device 210 is closed off from the surrounding environment in which the lighting device 210 is placed. Therefore, it is possible to prevent foreign matter such as dust present in the surrounding environment from entering the inside of the lighting device 210, and it is possible to realize a lighting device 210 with high reliability.

[0103] In the case of the light-transmitting member 254 having a diffusion filler dispersed therein, the light irradiating the irradiation object can be diffused while ensuring the concentration of light at the focusing point, so that it is possible to irradiate the irradiation object with light with even reduced brightness unevenness.

[0104] (Third embodiment) FIG. 15A is a schematic perspective view illustrating the lighting device according to the third embodiment. FIG. 15B is a schematic bottom view illustrating the light source module of the illumination device according to the third embodiment. 15A and 15B, the illumination device 310 according to this embodiment includes a light source module 315 that is different from the light source module 15 of the illumination device 10 shown in Fig. 1. In other respects, the configuration of the illumination device 310 is the same as that of the illumination device 10 according to the first embodiment. The same components are denoted by the same reference numerals, and detailed descriptions thereof will be omitted as appropriate.

[0105] As shown in FIG. 15B, the light source module 315 has a substrate 20 and light sources 30c and 30d. A plurality of light sources 30c and 30d are arranged on the substrate 20. The light sources 30c and 30d emit light of different emission colors, for example, the light source 30c emits daylight light, and the light source 30d emits light of incandescent light. By adjusting the luminance of the light emitted by each of the light sources 30c and 30d and mixing the light emitted by each of the light sources 30c and 30d, the color tone of the light irradiating the irradiation object can be appropriately set. The emission color of the light emitted by each of the light sources 30c and 30d is not limited to the above, but is appropriately selected depending on the color tone of the irradiation object and the environmental lighting in which the lighting device 310 is installed.

[0106] For example, the light sources 30c and the light sources 30d are alternately arranged in a ring shape. The alternate arrangement means that the light source 30d is arranged next to the light source 30c, and the light source 30c is arranged next to the light source 30d, and all the light sources 30c and 30d are sequentially arranged in a ring shape. The arrangement order of the light sources 30c and 30d is not limited to the above, but is appropriately set according to the object to be irradiated, the color tone of the environmental lighting in which the lighting device 310 is installed, or the shape of the arrangement in a plan view. In addition, the light sources 30c and 30d are not limited to being simultaneously emitting light, and one of the light sources 30c and 30d may be selected to emit light according to the object to be irradiated, for example.

[0107] The effects of the illumination device 310 according to this embodiment will be described. The lighting device 310 according to this embodiment has the same effects as the lighting device 10 shown in Fig. 1 etc. In addition, it has the following effects. That is, the lighting device 310 includes a light source module 315 in which a plurality of light sources 30c, 30d having different emission colors are arranged in a ring shape on the substrate 20. By appropriately setting the emission color of the light emitted by each of the light sources 30c, 30d, it is possible to realize appropriate lighting according to the object to be illuminated, the color tone of the environmental lighting in which the lighting device 310 is installed, the shape of the arrangement in a plan view, and the like.

[0108] (Fourth embodiment) FIG. 16A is a schematic perspective view illustrating an illumination device according to a fourth embodiment. FIG. 16B is a schematic bottom view illustrating the light source module of the illumination device according to the fourth embodiment. 16A and 16B, an illumination device 410 according to this embodiment includes a light source module 415 that is different from the light source module 15 of the illumination device 10 shown in Fig. 1. In other respects, the configuration of the illumination device 410 is the same as that of the illumination device 10 according to the first embodiment. The same components are denoted by the same reference numerals, and detailed descriptions thereof will be omitted as appropriate.

[0109] 16B, the light source module 415 includes a substrate 20 and light sources 30e, 30f, and 30g. A plurality of light sources 30e, 30f, and 30g are arranged on the substrate 20. The light sources 30e, 30f, and 30g emit light of different colors. For example, the light source 30e emits red light, the light source 30f emits green light, and the light source 30g emits blue light.

[0110] For example, the light sources 30e, 30f, and 30g are arranged in a ring shape in this order. That is, the light source 30e is arranged next to the light source 30d, the light source 30f is arranged next to the light source 30e, and the light source 30d is arranged next to the light source 30f. The arrangement order of the light sources 30d, 30e, and 30f is not limited to the above, and may be appropriately selected depending on the object to be irradiated, the color tone of the environmental lighting in which the lighting device 310 is installed, or the shape of the arrangement in a plan view.

[0111] In the lighting device 410 according to the present embodiment, the luminance of the light emitted by each of the light sources 30e, 30f, and 30g is adjusted, and the light emitted by each of the light sources 30e, 30f, and 30g is mixed, so that the color tone of the light to be irradiated to the irradiation object can be appropriately set. The color of the light emitted by each of the light sources 30e, 30f, and 30g is not limited to the above, but is appropriately selected depending on the color tone of the irradiation object and the environmental lighting in which the lighting device 310 is installed. In addition, the light sources 30e, 30f, and 30g may be selected to emit light depending on the irradiation object and the like, not limited to the case where the light sources 30e, 30f, and 30g are simultaneously emitted. Furthermore, the luminance of each of the light sources 30e, 30f, and 30g may be dynamically adjusted to irradiate the irradiation object with a desired color tone depending on the irradiation object and the like.

[0112] The effects of the illumination device 410 according to this embodiment will be described. The lighting device 410 according to this embodiment has the same effects as the lighting device 10 shown in Fig. 1 and the like. In addition, it has the following effects. That is, the lighting device 410 includes a light source module 415 in which a plurality of light sources 30e, 30f, and 30g having different emission colors are arranged in a ring shape on the substrate 20. By appropriately setting the emission color of the light emitted by each of the light sources 30e, 30f, and 30g, it is possible to realize appropriate lighting according to the object to be illuminated, the color tone of the environmental lighting in which the lighting device 410 is installed, the shape of the arrangement in a plan view, and the like.

[0113] Fifth embodiment FIG. 17A is a schematic bottom view illustrating the light source module of the illumination device according to the fifth embodiment. As shown in Fig. 17A, the lighting device according to this embodiment includes a light source module 515 that is different from the light source module 15 of the lighting device 10 shown in Fig. 1. In other respects, the configuration of the lighting device is the same as that of the lighting device 10 according to the first embodiment. The same components are denoted by the same reference numerals, and detailed descriptions thereof will be omitted as appropriate.

[0114] The light source module 515 has a substrate 20 and a plurality of light sources 30. The plurality of light sources 30 are arranged in a ring shape on the substrate 20, similar to the case of the light source module 15 shown in FIG. 3A and FIG. 3B. In this embodiment, some of the plurality of light sources 30 are arranged in a ring shape on the substrate 20, and the remaining light sources 30 of the plurality of light sources 30 are arranged in a ring shape surrounding the outside of the some of the light sources 30 arranged in a ring shape. That is, in this embodiment, in the light source module 515, the plurality of light sources 30 are arranged in a double circular ring shape.

[0115] The annular arrangement of the plurality of light sources 30 is not limited to twofold, but may be threefold, fourfold or more.

[0116] (Modification) FIG. 17B is a schematic bottom view illustrating a light source module of an illumination device according to a modified example of the fifth embodiment. FIG. 17C is a schematic bottom view illustrating a light source module of an illumination device according to another modification of the fifth embodiment. As shown in Figures 17B and 17C, multiple annular arrangements of multiple light sources may provide light sources with different emission colors.

[0117] In the light source module 515a, the light sources 30e, 30f, and 30g are arranged in a ring shape in this order, and the light sources 30e, 30f, and 30g are arranged in a ring shape outside of the light sources 30e, 30f, and 30g. In the light source module 515b, the light sources 30e, 30f, and 30g are arranged in a ring shape outside of the double ring shape of the light sources 30e, 30f, and 30g. That is, in the light source module 515a, the light sources 30e, 30f, and 30g are arranged in a double ring shape, and in the light source module 515b, the light sources 30e, 30f, and 30g are arranged in a triple ring shape. The light emission color emitted by the light sources, the order of the arrangement of the light sources, the light emission brightness of the light sources, and which light source is selected to emit light are appropriately selected according to the color tone of the illumination target and the surrounding environment in which the illumination device is installed, as in the case of the light source module 415 described in relation to FIG. 16A and FIG. 16B.

[0118] The effects of the illumination devices according to this embodiment and the modified example will be described. The lighting device according to the present embodiment and the modified example has the same effect as the lighting device 10 shown in FIG. 1 and the like. In addition, it has the following effects. That is, in the light source modules 515, 515a, and 515b provided in the lighting device, a plurality of light sources are arranged in a multiple ring shape on the substrate 20. This makes it possible to arrange a larger number of light sources on the substrate 20. By using the light emitting device 30a having the surface mount type package shown in FIG. 4 as the light source, the light source modules 515, 515a, and 515b have high heat dissipation through the substrate 20. By using a light source module equipped with a larger number of light sources, it is possible to realize a lighting device that can irradiate light having high brightness to an irradiation object.

[0119] Sixth embodiment FIG. 18A is a schematic top view illustrating the illumination device according to the sixth embodiment. FIG. 18B is a schematic perspective view illustrating the lighting device according to the sixth embodiment. As shown in FIG. 18A and FIG. 18B, the lighting device 610 according to this embodiment is different from the lighting device 10 shown in FIG. 1 in that it includes a light source module 615 having an arc-shaped substrate 620 and a plurality of light sources 30 arranged on the substrate 620. In addition, it is different from the lighting device 10 in that it includes a light reflecting member 640 formed in an arc-shaped shape in a planar view in correspondence with the light source module 615. In addition, it is different from the lighting device 10 in that it includes a housing 650 that is arc-shaped in a planar view in order to accommodate the arc-shaped light source module 615 and the light reflecting member 640. In other respects, the lighting device 610 has the same configuration as the lighting device 10 according to the first embodiment, and the same components are denoted by the same reference numerals, and detailed descriptions thereof will be omitted as appropriate.

[0120] In the light source module 615, the light sources 30 are arranged in an arc shape. The arc shape means a part of an annular shape. In this example, the light sources 30 are arranged in a semicircular shape on a semicircular substrate 620 that forms a part of an annular shape in a plan view. The light reflecting member 640 is arranged so as to surround the sides of the light sources 30 arranged in an arc shape and cover the light sources 30. The housing 650 houses the light source module 615 and the light reflecting member 640. The housing 650 has an opening 652A on the inside of the semicircular shape. The housing 650 is provided with end covers 655 at both ends in the circumferential direction of the semicircle. The light source module 615 and the light reflecting member 640 are closed from the external environment by the housing 650 and the end cover 655 except for the opening 652A.

[0121] As described above in relation to FIG. 7A and FIG. 7B, the light emitted from each of the multiple light sources 30 is reflected by the reflecting surface 42 of the light reflecting member 640, and after being collected at the collecting point, proceeds toward the inside and downward of the semicircle. The light is emitted from the opening 652A to the opening area WPa. The opening area WPa is an area inside the housing 650 and includes the opening 652A. In FIG. 20A, the two-dot chain line represents the opening area WPa as a circle including the inner diameter of the housing 650 in a plan view. As described above in relation to FIG. 8, the central axis A1 toward which the multiple light beams emitted from the multiple light sources 30 are directed passes through the center of the two-dot chain circle. The irradiation object is placed within the opening area WPa in a top view.

[0122] (Modification) FIG. 19A is a schematic top view illustrating an illumination device according to a modification of the sixth embodiment. FIG. 19B is a schematic perspective view illustrating an illumination device according to a modification of the sixth embodiment. As shown in FIGS. 19A and 19B, the illumination device 610a may have a ⅓ circle shape in a plan view. In the light source module 615a, a plurality of light sources 30 are arranged in a 1 / 3 circle shape on a substrate 620a having a 1 / 3 circle shape forming a part of a ring in a plan view. The light reflecting member 640a is formed in a 1 / 3 circle shape in a plan view and is provided so as to cover the plurality of light sources 30. A housing 650a having a 1 / 3 circle shape in a plan view houses the light source module 615a and the light reflecting member 640a therein.

[0123] The housing 650a has an opening 652A1 on the inner edge side of the 1 / 3 circle shape. As described above with reference to Figures 7A and 7B, the light emitted from each of the multiple light sources 30 is reflected by the reflecting surface 42 of the light reflecting member 640a, is collected at the light collecting point, and then travels downward toward the inner edge side of the 1 / 3 circle.

[0124] The light is emitted from the opening 652A1 to the opening area WPa. The opening area WPa is an area including the opening 652A1 inside the housing 650a, and in FIG. 19A, the two-dot chain line represents a circle including the inner diameter of the housing 650a. The central axis A1 along which the multiple light beams emitted from the multiple light sources 30 travel passes through the center of the two-dot chain circle. The object to be irradiated is placed within the opening area WPa.

[0125] The effects of the illumination devices 610 and 610a according to this embodiment and the modified example will be described. In the illumination devices 610 and 610a according to the present embodiment and the modified example, the light sources 30 are arranged in an arc shape, and the light reflecting members 640 and 640a are also formed in an arc shape to cover the light sources 30. Therefore, the light emitted by the light sources 30 travels toward the inside of the arc shape. The object to be irradiated is placed on the inside of the arc shape and below the illumination devices 610 and 610a. This allows the object to be illuminated from one direction diagonally above. When the unevenness of the surface of the object to be irradiated is difficult to see when it is irradiated from all directions, it is possible to observe the surface condition of the object to be irradiated in more detail by irradiating light from a certain direction.

[0126] In the above-described specific example, the illumination device 610 has a semicircular or 1 / 3 circular shape in a planar view, but is not limited thereto and may have any arc shape, such as a 1 / 4 circle, depending on the shape of the object to be illuminated and the condition of its surface.

[0127] Seventh embodiment 20A to 20C are schematic exploded views illustrating a method for manufacturing the illumination device according to the seventh embodiment. In this embodiment, a manufacturing method for forming an annular lighting device using the light source module 615 and light reflecting member 640 formed in an arc shape as described with reference to FIGS. 18A and 18B will be described.

[0128] 20A, a light source module 615 and a light reflecting member 640a are prepared. The prepared light source module 615 is coupled to a light reflecting member 640. In coupling the light source module 615 and the light reflecting member 640, the fitting convex portion 40b1 of the light reflecting member 640 is inserted into the fitting hole portion 24 provided in the substrate 620, and after the insertion, the tip of the fitting convex portion 40b1 is heat-treated to increase the diameter and fix it.

[0129] As shown in FIG. 20B, an intermediate member 705 formed by combining a light source module 615 and a light reflecting member 640 is prepared. Two intermediate members 705 are prepared. The intermediate member 705 has ends 706E1 and 706E2 at both ends. The end 706E1 is made up of an end 625E1 of the substrate 620 and an end 645E1 of the light reflecting member 640. The end 706E2 is made up of an end 625E2 of the substrate 620 and an end 645E2 of the light reflecting member 640. The ends 625E1 and 625E2 of the substrate 620 and the ends 645E1 and 645E2 of the light reflecting member 640 are both ends of a circular arc.

[0130] The two intermediate members 705 thus prepared are joined. In joining the intermediate members 705, as shown by the two arrows in FIG. 20B, the ends of the two intermediate members 705 are opposed to each other and joined. Specifically, in joining the ends, the end 706E1 of one intermediate member 705 and the end 706E2 of the other intermediate member 705 are opposed to each other and joined, and the end 706E2 of one intermediate member 705 and the end 706E2 of the other intermediate member 705 are opposed to each other and joined. In joining the ends 706E1 and 706E2, for example, the ends 625E1 and 625E2 of the substrate 620 are opposed to each other and joined, and the ends 645E1 and 645E2 of the light reflecting member 640 are opposed to each other and joined. For example, an adhesive can be used for these joinings.

[0131] 20C, it is possible to form an illumination section 715 by combining two intermediate members 705. The illumination section 715 can be housed in the housing 50 shown in FIG.

[0132] The intermediate member 705 described above in relation to FIG. 20A can also be stored in the housing 650 shown in FIG. 18A and the end of the housing 650 can be covered with an end cover 655 to form the lighting device 610 of the sixth embodiment.

[0133] In the above-described embodiment, as the intermediate member, for example, the 1 / 3 circle-shaped light source module 615a and the light reflecting member 40 shown in Fig. 19A and Fig. 19B may be combined and joined to form the illumination device 10 shown in Fig. 1. The intermediate member is not limited to a semicircular or 1 / 3 circle shape, and may be a 1 / 4 circle shape, etc.

[0134] The effects of the manufacturing method for the lighting device according to this embodiment will be described. In the manufacturing method of the lighting device according to the present embodiment, an intermediate member is formed by combining a light source module and a light reflecting member formed in an arc shape, and the intermediate members are combined and combined to form a lighting device. By making the length of the arc of the arc shape of the light source module and the light reflecting member an integer fraction of the length of the ring of the ring shape of the lighting device, intermediate members of the same shape can be combined to form a lighting device. In addition, by storing the light source module and the light reflecting member formed in an arc shape in an arc-shaped housing, it is possible to form an arc-shaped lighting device 610, 610a, etc., and the intermediate member can be shared by multiple types of lighting devices 10, 610, 610a. Therefore, it is possible to standardize the members, shorten the manufacturing period, and reduce management costs, manufacturing costs, etc.

[0135] Eighth embodiment FIG. 21 is a schematic cross-sectional view of an illumination device according to the eighth embodiment. As long as light having high brightness among the lights emitted from the multiple light sources 30 can reach a farther distance than light having low brightness through a focusing point, the reflecting surface of the light reflecting member does not need to be a curved surface. In the illumination device 810 according to this embodiment, the reflecting surface 842 of the light reflecting member 840 is made up of multiple reflecting surfaces 842a to 842h, and all of the reflecting surfaces 842a to 842h are planar reflecting surfaces. As shown in Fig. 21, an illumination device 810 according to this embodiment differs from the illumination device 10 shown in Fig. 1 in that it includes a light reflecting member 840. In other respects, the illumination device 810 has the same configuration as the illumination device 10 according to the first embodiment, and the same components are denoted by the same reference numerals and detailed descriptions thereof are omitted as appropriate. Note that the light reflecting member 840 is formed of a material such as resin or metal, similar to the light reflecting member 40 in the case of the illumination device 10 shown in Fig. 1.

[0136] The light reflecting member 840 has a reflecting portion 840a and a support portion 40b. The reflecting portion 840a has a reflecting surface 842. The reflecting surface 842 includes a plurality of reflecting surfaces 842a-842h. The plurality of reflecting surfaces 842a-842h are all flat reflecting surfaces. The plurality of reflecting surfaces 842a-842h are arranged to reflect the light emitted from the light source 30 and to focus the reflected light at a focusing point.

[0137] The reflecting surfaces 842a-842h are arranged in this order from the negative side to the positive side of the Z axis. That is, the reflecting surface 842h is located closer to the substrate 20 than the reflecting surface 842a. The angles of the reflecting surfaces 842a-842h from the Z axis decrease in this order. That is, the angle of the reflecting surface 842h from the Z axis is smaller than the angle of the reflecting surface 842a from the Z axis.

[0138] 7A and 7B, the light emitted from light source 30 that has the highest brightness and travels mainly in the Z-axis direction is reflected by reflecting surfaces (first reflecting surfaces) 842a to 842d, and the light that has a lower brightness is reflected by reflecting surfaces (second reflecting surfaces) 842e to 842h.

[0139] Since the angle of the reflecting surfaces 842a-842d from the Z axis is larger than the angle of the reflecting surfaces 842e-842h from the Z axis, the light having high brightness reflected by the reflecting surfaces 842a-842d reaches a farther distance than the light having low brightness reflected by the reflecting surfaces 842e-842h after passing through the light-converging point F1. Therefore, as in the case of the lighting device 10 shown in FIG. 1 etc., the brightness of the light having high brightness that reaches a farther distance weakens on the illuminated object, and becomes approximately the same as the brightness of the light having low brightness that reaches a closer distance, and the illuminated object is illuminated with light with reduced brightness unevenness.

[0140] The effects of the illumination device 810 according to this embodiment will be described. In the illumination device 810 according to this embodiment, the reflection surface 842 is formed by a plurality of flat reflection surfaces 842a to 842h, and the reflection surfaces 842a to 842d located farther from the substrate 20 than the reflection surfaces 842e to 842h reflect the light having the highest brightness. The reflection surfaces 842a to 842d are set at angles from the Z axis so as to condense the light when they reflect it, and are set at angles so as to reach a farther distance than the light Lb and Lc reflected by the reflection surfaces 842e to 842h. Therefore, the light having the highest brightness reaches a farther distance after passing the condensing point. The light having a lower brightness reaches a closer position after being reflected and condensed by the reflection surfaces 842e to 842h. Therefore, the illumination device 810 can irradiate the illumination object with light having reduced brightness unevenness.

[0141] Ninth embodiment FIG. 22 is a schematic block diagram illustrating an inspection apparatus according to the ninth embodiment. As shown in FIG. 22, the inspection device 1000 according to this embodiment includes an illumination device 10 and an imaging device 1120. The illumination device 10 is the illumination device according to the first embodiment shown in FIG. 1. The inspection device 1000 further includes a control device 1140.

[0142] The illumination device 10 is disposed above the inspection table 1130. An inspection object T1000 is placed on the inspection table 1130. The illumination device 10 is disposed at a distance WD10 from the surface of the inspection object T1000. The imaging device 1120 is disposed above the illumination device 10. The illumination device 10 emits a plurality of light beams L1 toward the inspection object T1000 and irradiates the inspection object T1000. The imaging device 1120 images the illuminated inspection object T1000 through the opening region WP of the illumination device 10.

[0143] For example, the imaging device 1120 is disposed so that the optical axis A2 of the lens of the imaging device 1120 coincides with the central axis A1 of the illumination device 10. The inspection object T1000 is disposed so that the center position of the inspection object T1000 approximately coincides with the central axis A1 and the optical axis A2.

[0144] The control device 1140 is electrically connected to the lighting device 10, the imaging device 1120, and the inspection table 1130. The control device 1140 supplies power to the lighting device 10 so that the lighting device 10 is turned on and emits a plurality of light beams L1. The control device 1140 transmits an imaging command to the imaging device 1120 to capture an image of the inspection object T1000. The imaging device 1120 captures an image of the inspection object T1000 based on the imaging command. The imaging device 1120 transmits image data including the captured image of the inspection object T1000 to the control device 1140.

[0145] The control device 1140 has, for example, an image processing function and an image recognition function. The image processing function and the image recognition function of the control device 1140 inspect the inspection target T1000 based on the image data acquired by the imaging device 1120, and perform, for example, a pass / fail judgment of the inspection result.

[0146] The control device 1140 may perform a pass / fail judgment of the image data acquired by the imaging device 1120. For example, the control device 1140 can adjust the luminance of the light L1 of the illumination device 10 based on the pass / fail judgment result, set optimal illumination conditions, and then acquire image data for inspection judgment.

[0147] The control device 1140 may drive and control the inspection table 1130 that is movable in the X-axis direction. As in the example of Fig. 22, a plurality of inspection objects T1000 are placed on the inspection table 1130 at equal intervals along the X-axis direction. The inspection table 1130 is moved in the X-axis direction by, for example, the control device 1140. By setting the moving distance to the interval at which the inspection objects T1000 are placed, the inspection device 1000 can sequentially inspect the plurality of inspection objects T1000.

[0148] (Variation 1) FIG. 23 is a schematic block diagram illustrating an inspection device according to a modified example of the ninth embodiment. As shown in Fig. 23, the inspection apparatus 1000a according to this embodiment differs from the inspection apparatus 1000 shown in Fig. 22 in that it includes an illumination device 610. In other respects, the inspection apparatus 1000a is the same as the inspection apparatus 1000 according to the ninth embodiment, and the same components are denoted by the same reference numerals and detailed descriptions thereof will be omitted as appropriate.

[0149] The illumination device 610 is disposed above the inspection object T1000 at a distance WD10 from the surface of the inspection object T1000. The imaging device 1120 is disposed above the illumination device 610. For example, the imaging device 1120 is disposed such that the optical axis A2 of the lens of the imaging device 1120 coincides with the central axis A1 of the illumination device 610. The inspection object T1000 is placed on the inspection table 1130 such that the center position of the inspection object T1000 approximately coincides with the central axis A1 and the optical axis A2.

[0150] In this modification, a semicircular illumination device 610 is provided, and the illumination device 610 emits a plurality of light beams L1 toward the inspection object T1000 from one direction obliquely above the inspection object T1000. Therefore, the inspection object T1000 can be effectively illuminated according to its surface shape. The illumination device 610 may be rotated around the central axis A1 by the control device 1140. In this way, it is possible to obtain image data of the inspection object T1000 according to the direction of illumination.

[0151] (Variation 2) FIG. 24 is a schematic cross-sectional view illustrating a part of an inspection device according to another modified example of the ninth embodiment. As shown in Fig. 24, in the inspection device according to this modification, the illumination device 1010 is different from the inspection device 1000 shown in Fig. 22 in that it includes a light reflecting member 1040 different from the light reflecting member shown in Fig. 1. In other respects, the inspection device according to this modification is the same as the inspection device 1000 according to the ninth embodiment, and the same components are denoted by the same reference numerals and detailed descriptions thereof will be omitted as appropriate.

[0152] In the illumination device 1010 of the inspection device of this modification, the light reflecting member 1040 has a reflection surface 1042 on the reflection part 1040a. The reflection surface 1042 is a reflection surface that is a straight line in a cross-sectional view on a plane parallel to the XZ plane. In this modification, the distance WD20 between the surface of the inspection object T1000 and the illumination device 1010 is sufficiently longer than, for example, WD1 shown in FIG. 7A and FIG. 7B. In such a case, the curvature of the curved surface of the reflection surface 1042 can be sufficiently large without forming a light-converging point near the reflection surface 1042. Even if the reflection surface 1042 is made substantially flat, when the light L1 reaches the inspection object T1000, the light with reduced luminance unevenness is irradiated regardless of the direction of the light in the light source 30.

[0153] The effects of the inspection devices 1000 and 1000a according to this embodiment and Modification 1 will be described. The inspection apparatus 1000 includes the illumination device 10, and thus has the effects of the illumination device 10 according to the first embodiment, as well as the following effects. That is, the illumination device 10 appropriately sets the emission directions of the multiple light beams L1 according to the distance WD10 between the illumination device 10 and the inspection target T1000. Therefore, it is possible to irradiate the inspection target T1000 so as to appropriately represent the surface condition thereof, and it is possible to obtain more appropriate image data for inspection and judgment of the inspection target T1000.

[0154] 7A and 7B, an appropriate reflective surface can be designed according to the distance between the illumination device and the inspection target T1000, and the illumination device 10 having a light reflecting member having an appropriate reflective surface can be easily obtained. In the inspection device 1000, by applying the above, the illumination device 10 is designed according to the distance between the illumination device and the inspection target T1000, and appropriate image data for inspection judgment can be obtained.

[0155] Furthermore, when the distance to the inspection target T1000 is sufficient, the inspection device according to the modified example 2 can apply the illumination device 1010. The illumination device 1010 has an advantage that the structure of the light reflecting member 1040 is simpler and therefore easier to manufacture.

[0156] In the inspection apparatus 1000a according to the modified example, by applying the illumination device 610, image data of the surface condition and the like of the inspection target T1000 based on the illumination direction can be easily obtained.

[0157] According to the embodiment described above, it is possible to realize an illumination device and an inspection device that illuminate an object to be illuminated with light having reduced luminance unevenness.

[0158] Although several embodiments of the present invention have been described above, these embodiments are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their modifications are included within the scope and spirit of the invention, and are included in the scope of the invention and its equivalents described in the claims. In addition, the above-mentioned embodiments can be implemented in combination with each other.

[0159] The embodiments include the following aspects.

[0160] (Appendix 1) a light source module including a substrate having a first surface, and a plurality of light sources arranged on the first surface, each of the light sources capable of emitting light including a first light and a second light having a lower luminance than the first light; a light reflecting member having a reflecting surface that reflects the light emitted from each of the plurality of light sources; Equipped with the reflective surface includes a first reflective surface that reflects the first light and a second reflective surface that reflects the second light, the second reflecting surface is located closer to the substrate than the first reflecting surface, The lighting device in which the light emitted from one of the plurality of light sources is focused at a focusing point, with the first light being reflected by the first reflecting surface and the second light being reflected by the second reflecting surface.

[0161] (Appendix 2) The light emitted by each of the plurality of light sources has a Lambertian light distribution, and the lighting device according to Appendix 1.

[0162] (Appendix 3) The first reflecting surface reflects the plurality of first lights emitted by the plurality of light sources. The second reflecting surface reflects the plurality of second lights emitted by the plurality of light sources. The plurality of first lights and the plurality of second lights are respectively focused at the plurality of focus points, and the lighting device according to Appendix 1 or 2.

[0163] (Appendix 4) The plurality of light sources are arranged in a ring. The plurality of lights emitted by the plurality of light sources are respectively reflected by the reflecting surface and travel respectively toward the irradiation object, and the lighting device according to any one of Appendices 1 to 3.

[0164] (Appendix 5) The plurality of light sources are arranged in an arc. The plurality of lights emitted by the plurality of light sources are respectively reflected by the reflecting surface and travel respectively toward the irradiation object, and the lighting device according to any one of Appendices 1 to 3.

[0165] (Appendix 6) Some of the plurality of light sources are arranged outside the remaining light sources among the plurality of light sources, and the lighting device according to Appendix 4 or 5.

[0166] (Appendix 7) The focus point is located between the reflecting surface and the irradiation object, and the lighting device according to any one of Appendices 4 to 6.

[0167] (Appendix 8) The first reflecting surface is a curved surface continuous with the second reflecting surface. The curved surface satisfies the relationship that the conic constant k of the aspherical polynomial is -1 < k < 0, and the lighting device according to any one of Appendices 1 to 7.

[0168] (Appendix 9) the first reflecting surface includes a plurality of reflecting planes at different angles to each other, 8. The lighting device according to claim 1, wherein the second reflecting surface includes a plurality of reflecting planes each having a different angle.

[0169] (Appendix 10) 10. The lighting device according to claim 1, wherein each of the plurality of light sources is a surface-mounted light-emitting device including a light-emitting element.

[0170] (Appendix 11) The lighting device according to any one of claims 1 to 10, further comprising a housing that houses the light source module and the light reflecting member, has an opening through which the light reflected by the reflecting surface exits, and has an outer surface that is a light absorbing surface.

[0171] (Appendix 12) 12. The lighting device according to claim 11, wherein the housing includes a light-transmitting member that covers the opening.

[0172] (Appendix 13) 13. The lighting device according to claim 1, wherein the plurality of light sources have different emission colors.

[0173] (Appendix 14) a light source module including a substrate having a first surface and a plurality of light sources capable of emitting light, each of which includes a first light and a second light having a lower luminance than the first light, on the first surface; a light reflecting member having a reflecting surface that reflects light emitted from each of the plurality of light sources; A plurality of intermediate members including In each of the plurality of intermediate members, the reflective surface includes a first reflective surface that reflects the first light and a second reflective surface that reflects the second light, the second reflecting surface is located closer to the substrate than the first reflecting surface, the light emitted from one light source among the plurality of light sources is focused at a focusing point as the first light reflected by the first reflecting surface and the second light reflected by the second reflecting surface; The plurality of light sources are arranged in an arc shape, The light beams emitted from the light sources are reflected by the reflecting surface and travel toward an object to be illuminated, The plurality of intermediate members are interconnected to form a lighting device.

[0174] (Appendix 15) A lighting device; an imaging device that is disposed at a distance from the illumination device and captures an image of an inspection object illuminated with light emitted from the illumination device; Equipped with The lighting device includes: a light source module including a substrate having a first surface, and a plurality of light sources arranged on the first surface, each of the light sources capable of emitting light including a first light and a second light having a lower luminance than the first light; a light reflecting member that reflects the light emitted from each of the plurality of light sources; having the reflective surface includes a first reflective surface that reflects the first light and a second reflective surface that reflects the second light, The second reflecting surface is located closer to the substrate than the first reflecting surface.

[0175] (Appendix 16) 16. The inspection apparatus according to claim 15, wherein the light emitted from one of the plurality of light sources in the illumination device is focused at a focusing point as the first light reflected by the first reflecting surface and the second light reflected by the second reflecting surface. [Explanation of symbols]

[0176] 10, 210, 310, 410, 610, 610a, 810... Illumination device, 15, 315, 415, 515, 515a, 515b, 615, 615a... Light source module, 20, 620, 620a... Substrate, 30, 30c, 30d, 30e, 30f, 30g... Light source, 30a, 30b... Light emitting device, 31a, 31b... Light emitting element, 32... Electrode, 33... Lead, 34, 36... Resin molded body, 35... Sealing Member, 37...light-transmitting member, 40, 640, 640a, 840, 1040...light-reflecting member, 42, 42a, 42b, 42c, 842, 842a to 842h, 1042...reflecting surface, 50, 650, 650a...housing, 52A, 652A, 652A1...opening, 705...intermediate member, 715...illumination unit, 1000, 1000a...inspection device, 1120...imaging device, 1130...inspection table, 1140...control device

Claims

1. A light source module comprising a substrate having a first surface, and a plurality of light sources arranged on the first surface, each capable of emitting light including a first light and a second light having lower brightness than the first light, A light-reflecting member having a reflective surface that reflects the light emitted from each of the plurality of light sources, wherein the reflective surface is arranged on a first surface, Equipped with, The reflective surface includes a first reflective surface that reflects the first light and a second reflective surface that reflects the second light. The second reflective surface is located closer to the substrate than the first reflective surface. An illumination device in which the light emitted from one of the plurality of light sources is focused at a focal point located on the first surface side of the substrate, with the first light reflected by the first reflective surface and the second light reflected by the second reflective surface being focused together.

2. The lighting device according to claim 1, wherein the light emitted from each of the plurality of light sources has a Lambertsian light distribution.

3. The first reflective surface reflects the plurality of first light emitted from the plurality of light sources, The second reflective surface reflects the multiple second lights emitted by the multiple light sources, The illumination device according to claim 1, wherein the plurality of first lights are focused together with the plurality of second lights at the plurality of focusing points.

4. The substrate has an aperture region, The plurality of light sources are arranged in a ring around the aperture region. The multiple light sources emitted by the multiple light sources are each reflected by the reflective surface and each travels toward the object to be illuminated. The lighting device according to claim 1, wherein, in a plan view, the central axis of the aperture region perpendicular to the first surface coincides with the object to be illuminated.

5. The aforementioned multiple light sources are arranged in an arc shape, The illumination device according to claim 1, wherein the plurality of light emitted from the plurality of light sources is reflected by the reflective surface and travels toward the object to be illuminated.

6. The lighting device according to claim 4, wherein some of the multiple light sources are arranged outside of the remaining multiple light sources.

7. The illumination device according to claim 4, wherein the focusing point is located between the reflective surface and the object to be illuminated.

8. The first reflective surface is a curved surface continuous with the second reflective surface, The lighting device according to claim 1, wherein the curved surface satisfies the relationship -1 < k < 0 for the cone constant k of the aspherical polynomial.

9. The first reflective surface includes a plurality of reflective planes that are at different angles to each other. The lighting device according to claim 1, wherein the second reflective surface includes a plurality of reflective planes having different angles to each other.

10. The lighting device according to claim 1, wherein each of the plurality of light sources is a surface-mount type light-emitting device including a light-emitting element.

11. The lighting device according to claim 1, further comprising a housing that houses the light source module and the light reflecting member, has an opening for emitting the light reflected by the reflecting surface, and whose outer surface is a light absorbing surface.

12. The lighting device according to claim 11, wherein the housing includes a light-transmitting member that covers the opening.

13. The lighting device according to claim 1, wherein the plurality of light sources have different emission colors.

14. A light source module comprising a substrate having a first surface, and a plurality of light sources capable of emitting light on the first surface, each including a first light and a second light having lower brightness than the first light, A light-reflecting member having a reflective surface that reflects the light emitted from each of the aforementioned multiple light sources, It comprises multiple intermediate members including In each of the aforementioned intermediate members, The reflective surface includes a first reflective surface that reflects the first light and a second reflective surface that reflects the second light. The second reflective surface is located closer to the substrate than the first reflective surface. The light emitted from one of the plurality of light sources is focused at a focal point by the first light reflected by the first reflective surface and the second light reflected by the second reflective surface. The aforementioned multiple light sources are arranged in an arc shape, The multiple beams of light emitted from each of the multiple light sources are reflected by the reflective surface and travel toward the object to be illuminated. The aforementioned plurality of intermediate members are interconnected in a lighting device.

15. Lighting equipment, An imaging device is positioned at a distance from the aforementioned lighting device and captures an image of an object to be inspected that is illuminated by light emitted from the aforementioned lighting device. Equipped with, The aforementioned lighting device is A light source module comprising a substrate having a first surface, and a plurality of light sources arranged on the first surface, each capable of emitting light including a first light and a second light having lower brightness than the first light, A light reflecting member that reflects the light emitted from each of the plurality of light sources, It has, The reflective surface includes a first reflective surface that reflects the first light and a second reflective surface that reflects the second light. The inspection device wherein the second reflective surface is located closer to the substrate than the first reflective surface.

16. The inspection apparatus according to claim 15, wherein the illumination device is configured such that the light emitted from one of the plurality of light sources is focused at a focal point, with the first light reflected by the first reflective surface and the second light reflected by the second reflective surface being focused together.

Images