Lighting device

Abstract

To provide a lighting device that can stably illuminate a region to be illuminated in a predetermined form.SOLUTION: A lighting device 10 includes a light source, a shaping optical system, a light diffusion element 40, and a casing 50. The light source emits coherent light. The shaping optical system shapes coherent light that is emitted from the light source. The light diffusion element 40 diffuses coherent light that is shaped by the shaping optical system. The casing 50 accommodates the light source, the shaping optical system, and the light diffusion element 40. The light source, the shaping optical system, and the light diffusion element 40 are fixed to the casing 50 so as not to be detachable.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present disclosure relates to a lighting device.

Background Art

[0002] As disclosed in Patent Document 1 as an example, there is known a lighting device having a light source that emits coherent light and a diffractive optical element that diffracts the coherent light from the light source, and that illuminates an illuminated area having a shape corresponding to the diffraction pattern of the diffractive optical element. In the lighting device of Patent Document 1, the diffractive optical element is rotatably supported. Such a lighting device can adjust the orientation of the illuminated area by rotating the diffractive optical element as the orientation of the lighting device changes with respect to the irradiated surface irradiated with the light from the lighting device.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] Here, there is a demand for a lighting device that stably illuminates an illuminated area in a predetermined shape. However, in a lighting device in which a diffractive optical element is movably provided with respect to a light source, there is a risk that the relative position between the light source and the diffractive optical element may unintentionally change due to an impact, vibration, or the like transmitted to the lighting device. When the relative position changes, it may not be possible to illuminate the illuminated area in a predetermined shape.

[0005] An object of the present disclosure is to provide a lighting device capable of stably illuminating an illuminated area in a predetermined shape.

Means for Solving the Problems

[0006] A lighting device according to an embodiment of the present disclosure is A light source that emits coherent light, An optical shaping system that shapes the coherent light emitted from the light source, A light diffusing element that diffuses the coherent light shaped by the optical shaping system, A casing that houses the light source, the optical shaping system, and the light diffusing element, The light source, the optical shaping system, and the light diffusing element are fixedly and non-removably attached to the casing.

[0007] In the lighting device according to an embodiment of the present disclosure, The light diffusing element may be a diffractive optical element.

[0008] In the lighting device according to an embodiment of the present disclosure, The light diffusing element may be a microlens array.

[0009] The lighting device according to an embodiment of the present disclosure may further include a battery that supplies power to the light source, The battery may be housed in the casing and fixedly and non-removably attached to the casing.

[0010] The lighting device according to an embodiment of the present disclosure, A secondary battery that supplies power to the light source, An external connection terminal that is detachably connected to an external power supply device, may be further included, The secondary battery may be charged via the external connection terminal.

[0011] The lighting device according to an embodiment of the present disclosure may further include an external connection terminal that is detachably connected to an external power supply device, Power may be supplied from the power supply device to the light source via the external connection terminal.

[0012] In the lighting device according to an embodiment of the present disclosure, The casing may include a plurality of casing components that define a space for housing the light source, the optical shaping system, and the light diffusing element, The plurality of casing parts may be inseparably connected to each other.

[0013] In the lighting device according to one embodiment of the present disclosure, The plurality of casing parts may be connected via a sealing material.

[0014] In the lighting device according to one embodiment of the present disclosure, The light source may emit visible light.

[0015] The lighting device according to one embodiment of the present disclosure may further include a circuit board electrically connected to the light source, The casing may house the circuit board.

[0016] In the lighting device according to one embodiment of the present disclosure, The light diffusing element may have an incident surface on which light from the shaping optical system is incident, Unevenness for diffusing the light from the shaping optical system may be formed on the incident surface.

[0017] In the lighting device according to one embodiment of the present disclosure, The light diffusing element may have an exit surface from which the light incident on the incident surface exits, The unevenness may be formed over the entire region of at least the area of the incident surface that overlaps with the exit surface when the light diffusing element is viewed in the direction from the exit surface toward the incident surface.

[0018] The lighting device according to one embodiment of the present disclosure may emit only the light diffused by the light diffusing element.

[0019] In the lighting device according to one embodiment of the present disclosure, Anti-rolling means may be provided on the outer peripheral surface of the casing.

Advantages of the Invention

[0020] According to the present disclosure, it is possible to provide an illumination device that can stably illuminate an illuminated area in a predetermined shape.

Brief Description of the Drawings

[0021]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Embodiments for Carrying Out the Invention

[0022] Hereinafter, an embodiment of the present disclosure will be described with reference to the drawings. In the drawings attached to this specification, for the convenience of illustration and easy understanding, the scale, aspect ratio in the vertical and horizontal directions, etc. are appropriately changed and exaggerated from those of the actual object.

[0023] To clarify the directional relationship between drawings, in some drawings, the first direction D1, the second direction D2, and the third direction D3 are indicated by arrows as common directions between the drawings. The tip side of the arrow is one side of each of the directions D1, D2, and D3. An arrow pointing forward from the paper surface along the direction perpendicular to the paper surface of the drawing is indicated by a symbol with a dot in a circle as shown in FIG. 3. Also, an arrow pointing backward into the paper surface along the direction perpendicular to the paper surface of the drawing is indicated by a symbol with an "x" in a circle as shown in FIG. 10, for example.

[0024] Terms used in this specification that specify shapes, geometric conditions, and their degrees, such as "parallel", "perpendicular", "identical", etc., as well as values of lengths and angles, are not limited to strict meanings, but are interpreted to include ranges to the extent that similar functions can be expected.

[0025] The lighting device 10 in the present embodiment illuminates the illuminated area 90 on the irradiated surface 95. The lighting device 10 is devised to stably illuminate the illuminated area 90 in a predetermined shape.

[0026] Hereinafter, an embodiment will be described with reference to the specific examples shown in the drawings.

[0027] In the illustrated example, the lighting device 10 is a portable lighting device. That is, the lighting device 10 can be carried by the user without using special means. Therefore, by the user carrying the lighting device 10, lighting can be performed at a desired location. Especially in the illustrated example, the lighting device 10 is sufficiently reduced in size and weight and is configured as a portable lighting device. Since the lighting device 10 is a portable type that is sufficiently reduced in size and weight, the irradiated surface 95 to which coherent light is to be irradiated can be appropriately changed according to the situation.

[0028] The lighting device 10 irradiates the irradiated surface 95 with coherent light. According to such a lighting device 10, a large-area illuminated area 90 can be illuminated on the irradiated surface 95.

[0029] In the illustrated example, the lighting device 10 illuminates the illuminated area 90 in the shape of an arrow, but is not limited thereto. The lighting device 10 may illuminate the illuminated area 90 in a shape representing any one or more of characters, patterns, color patterns, symbols, marks, illustrations, characters, pictograms. The illuminated area 90 may have a shape extending along a straight line.

[0030] As shown in FIG. 3, the lighting device 10 includes a light source 20, a shaping optical system 30, a light diffusing element 40, and a casing 50. In the illustrated example, the lighting device 10 further includes a battery 70, a circuit board 72, a switch 74, and an operation lamp 76.

[0031] The light source 20 is not particularly limited as long as it is a component that emits coherent light. The light source 20 emits coherent light with a constant wavelength and aligned phases. Since the light emitting point of the light source 20 is minute, the emitted coherent light can have high directivity. Therefore, the light source 20 is suitable for the lighting device 10 that illuminates a distant area. Various types of light sources can be used as the light source 20. As the light source 20, a laser light source that oscillates laser light may be used. As the laser light source, a semiconductor laser light source can be exemplified. In the example shown in FIG. 3, the light source 20 emits visible light. Also, in the example shown in FIG. 3, the light source 20 includes a single coherent light source. Therefore, in the example shown in FIG. 3, the illuminated area 90 is illuminated with coherent light of a color corresponding to the wavelength range of the coherent light oscillated from the light source 20.

[0032] In the illustrated example, the light source 20 includes a light emitting unit 21 that includes a light emitting element, and a lead terminal 22 that electrically connects the light emitting unit 21 and the circuit board 72. Note that the light emitting unit 21 of the light source 20 and the circuit board 72 may be electrically connected via a socket. The light source 20 is electrically connected to the battery 70 via the circuit board 72 and the switch 74.

[0033] In the illustrated lighting device 10, the light source 20 emits coherent light at an output less than the maximum rated output, preferably at an output that is half of the maximum rated output.

[0034] The shaping optical system 30 shapes the light emitted from the light source 20. For example, the shaping optical system 30 shapes the shape of the cross-section orthogonal to the optical axis of the coherent light and the three-dimensional shape of the coherent light. The shaping optical system 30 may expand the cross-sectional area of the coherent light in a cross-section orthogonal to the optical axis of the coherent light.

[0035] In the example shown in FIG. 3, the shaping optical system 30 shapes the light emitted from the light source 20 into collimated light with an expanded width. That is, the shaping optical system 30 functions as a collimating optical system. In the example shown in FIG. 3, the shaping optical system 30 has a first lens 31, a second lens 32, and a third lens 33 arranged along the optical path. The first lens 31, the second lens 32, and the third lens 33 shape the divergent light emitted from the light source 20 into collimated light. The entire lens group functions as a collimating lens. By providing positive or negative refractive power to each incident surface and exit surface of the lens and adjusting it, the influence of aberration can be effectively suppressed. As shown in FIG. 4, the shaping optical system 30 may consist of the first lens 31 and the second lens 32. In this case, the first lens 31 shapes the light emitted from the light source 20 into divergent light, and the second lens 32 shapes the divergent light generated by the first lens 31 into collimated light. Also in the example shown in FIG. 4, the first lens 31 and the second lens 32 can be made to function as a collimating lens that suppresses aberration.

[0036] The light diffusing element 40 diffuses the light emitted from the shaping optical system 30 and directs it toward the irradiated surface 95. The light diffusing element 40 has an incident surface 41 on which the light from the shaping optical system 30 is incident, and an exit surface 42 from which the light incident on the incident surface 41 exits. Fine irregularities for diffusing the light from the shaping optical system 30 are formed on the incident surface 41. The incident surface 41 is a surface facing the inside of the casing 50. Therefore, by forming the irregularities on the incident surface 41, the risk that the light diffusing element 40 is damaged and the irregularities are lost is suppressed. As a result, the light from the shaping optical system 30 can be reliably diffused by the light diffusing element 40.

[0037] The above-mentioned irregularities of the light diffusing element 40 are formed over the entire area of at least the region of the incident surface 41 that overlaps with the exit surface 42 when viewed in the direction from the exit surface 42 to the incident surface 41 of the light diffusing element 40. Thereby, the risk that the coherent light from the shaping optical system 30 is emitted from the lighting device 10 without being diffused by the light diffusing element 40 is suppressed.

[0038] In the illustrated example, the light diffusing element 40 is a diffractive optical element. By using a diffractive optical element as the light diffusing element 40, it is possible to illuminate the illuminated region 90 with high precision in a desired shape. In particular, the edge of the illuminated region 90 can be sharpened.

[0039] The diffractive optical element 40 as the light diffusing element changes the traveling direction of the coherent light from the light source 20. The coherent light diffracted by the diffractive optical element 40 illuminates the illuminated region 90 on the irradiated surface 95. The diffractive optical element 40 diffracts the coherent light from the light source 20 and directs it toward the illuminated region 90 on the irradiated surface 95. As a result, diffracted light from the diffractive optical element 40 is projected onto the irradiated surface 95. On the irradiated surface 95, the illuminated region 90 is illuminated in a shape corresponding to the diffraction pattern by the diffractive optical element 40.

[0040] The diffractive optical element 40 may be a hologram element. By using a hologram element as the diffractive optical element 40, it becomes easier to design the diffraction characteristics of the diffractive optical element 40. It is possible to relatively easily design a hologram element that can project light only onto the entire area of a desired region having a predetermined position, contour shape, size, and orientation on the irradiated surface 95. The region irradiated with coherent light on the irradiated surface 95 becomes the illuminated region 90.

[0041] When designing the diffractive optical element 40, the illuminated region 90 is set in real space at a predetermined position, with a predetermined contour shape, size, and orientation, with respect to the diffractive optical element 40. The position, contour shape, size, and orientation of the illuminated region 90 on the irradiated surface 95 depend on the diffraction characteristics of the diffractive optical element 40. By adjusting the diffraction characteristics of the diffractive optical element 40, the position, contour shape, size, and orientation of the illuminated region 90 on the irradiated surface 95 can be arbitrarily adjusted. Therefore, when designing the diffractive optical element 40, first, the position, contour shape, size, and orientation of the illuminated region 90 on the irradiated surface 95 are determined. Next, the diffraction characteristics of the diffractive optical element 40 may be adjusted so that light can be projected onto the entire determined illuminated region 90.

[0042] The diffractive optical element 40 can be fabricated as a computer-generated hologram (CGH). A computer-generated hologram is fabricated by calculating, on a computer, a structure having arbitrary diffraction characteristics. Therefore, by adopting the computer-generated hologram as the diffractive optical element 40, it is possible to eliminate the need to generate object light and reference light using a light source and an optical system, and to record interference fringes on a hologram recording material by exposure. The illumination device 10 is assumed to irradiate a coherently illuminated area 90 having a predetermined contour shape, size, and orientation with coherent light at a position predetermined with respect to the illumination device 10. By inputting information about the illuminated area 90 as a parameter into a computer, a structure having diffraction characteristics capable of projecting diffracted light onto the illuminated area 90, for example, a concavo-convex surface, can be specified by computation on the computer. By forming the specified structure, for example, by resin molding, the diffractive optical element 40 as a computer-generated hologram can be fabricated at low cost in a simple procedure.

[0043] For the design of the diffractive optical element 40, for example, the iterative Fourier transform method may be used. When the iterative Fourier transform method is used, the process is performed on the premise that the illuminated area 90 is far from the diffractive optical element 40, and the image projected onto the irradiated surface 95 may be regarded as a Fraunhofer diffraction image. Therefore, the irradiated surface 95 may be non-parallel to the diffraction surface of the diffractive optical element 40.

[0044] As shown in FIG. 5, the diffractive optical element 40 as a light diffusing element may include a plurality of element diffractive optical elements 45. Each individual element diffractive optical element 45 is, for example, a hologram element and may be configured in the same manner as the diffractive optical element 40 described above. In the example shown in FIG. 5, the coherent light diffracted by the plurality of element diffractive optical elements 45 is irradiated onto the same illuminated region 90. That is, the light diffracted by each element diffractive optical element 45 irradiates the entire area of the illuminated region 90 on the irradiated surface 95. According to such a diffractive optical element 40, the light directed to each position within the illuminated region 90 can be dispersed and emitted from the plurality of element diffractive optical elements 45 included in the diffractive optical element 40. Thereby, it is possible to suppress the local increase in irradiance or radiation intensity at each position on the diffractive optical element 40, and improve laser safety.

[0045] Each element diffractive optical element 45 may be configured to have the same diffraction characteristics as each other. However, in order to achieve more accurate projection, each element diffractive optical element 45 may be given separately designed diffraction characteristics according to the arrangement position of the element diffractive optical element 45 within the diffractive optical element 40. According to this example, each element diffractive optical element 45 can accurately direct the diffracted light of light only to the entire area of the illuminated region 90 on the irradiated surface 95 by adjusting the diffraction characteristics according to the difference in the arrangement with other element diffractive optical elements 45.

[0046] The battery 70 may be a primary battery or a rechargeable secondary battery. In the illustrated example, the battery 70 is a secondary battery. As shown in FIG. 6, an external connection terminal 71 is electrically connected to the battery 70 via a circuit board 72. The external connection terminal 71 is detachably connected to an external power supply device. The battery 70 is charged via the external connection terminal 71. Further, when there is no battery 70 or when the remaining amount of the battery 70 is zero, the external connection terminal 71 may be configured such that power can be directly supplied from the external power supply device to the light source 20. When the battery 70 is a secondary battery, the lighting device 10 does not necessarily need to be configured such that the battery 70 can be removed. For this reason, as will be described later, the casing 50 can be configured to be non-detachable. Thereby, the risk of moisture entering the interior of the lighting device 10 and the risk of the user of the lighting device 10 accessing the light source 20, the shaping optical system 30, the light diffusing element 40, the battery 70, the circuit board 72, etc. housed in the casing 50 are suppressed.

[0047] The circuit board 72 is electrically connected to each of the light source 20, the battery 70, and the external connection terminal 7, When the switch 74 is operated, the circuit board 72 electrically connects the light source 20 to the battery 70 or the external connection terminal 71, or cuts off the electrical connection between the light source 20 and the battery 70 or the external connection terminal 71. Thereby, the power supply to and the power supply stop from the battery 70 or the external power supply device to the light source 20 are switched.

[0048] In the illustrated example, the switch 74 has an operation unit 75 and an elastic member (not shown) that supports the operation unit 75. The operation unit 75 is movable between a connection position where the circuit board 72 electrically connects the light source 20 to the battery 70 or the external connection terminal 71, and a non-connection position where the electrical connection between the light source 20 and the battery 70 or the external connection terminal 71 via the circuit board 72 is interrupted. When the operation unit 75 is pushed toward the circuit board 72, the elastic member deforms and the operation unit 75 moves from the non-connection position to the connection position. As a result, the light source 20 and the battery 70 or the external connection terminal 71 are electrically connected via the circuit board 72, and power is supplied from the battery 70 or an external power supply device to the light source 20. As a result, the light source 20 lights up and emits coherent light. Also, when the force pushing the operation unit 75 toward the circuit board 72 is removed, the operation unit 75 returns to the connected position by the restoring force of the elastic member. As a result, the electrical connection between the light source 20 and the battery 70 or the external connection terminal 71 via the circuit board 72 is interrupted, and the power supply from the battery 70 or an external power supply device to the light source 20 is stopped. As a result, the light source 20 goes out. In the above description, the switch 74 is a tactile switch that can supply power to the light source 20 only while being pressed, but various power supply forms can be selected without being limited to this mode. For example, by incorporating a logic IC in the circuit board 72, continuous power supply to the light source 20 can be performed by pressing the switch 74 only once, and the power supply to the light source 20 can be stopped by pressing it again. Also, by adopting a type of switch 74 that can physically hold and release the pushed-in state, continuous power supply to and power supply stop from the light source 20 can also be performed.

[0049] In the illustrated example, as will be described later, a sealing material 66 is disposed between the operation unit 75 and the casing 50. Thereby, the operation unit 75 and the casing 50 are connected in a watertight manner, and the waterproof performance of the lighting device 10 is improved. That is, it is possible to suppress the risk that moisture enters the interior of the lighting device 10 through the gap between the operation unit 75 and the casing 50 and causes a malfunction in the operation of the lighting device 10. The sealing material 66 may be constituted by an adhesive or a rubber packing. Further, a sealing material 66 that seals between the operation unit 75 and the casing 50 may be formed by applying a water-repellent material or the like to the gap between the operation unit 75 and the casing 50.

[0050] The operation lamp 76 is electrically connected to the circuit board 72. The operation lamp 76 lights up during charging of the battery 70 and when charging is completed. Thereby, the user can grasp the charging state of the battery 70 through the operation lamp 76. Further, the operation lamp 76 lights up when the switch 74 is pushed in and disposed at the connection position. Thereby, the user can grasp that the light source 20 and the battery 70 or the external connection terminal 71 are electrically connected through the operation lamp 76. Note that the operation lamp 76 may be configured to light up in different colors when the battery 70 is charging, when the charging of the battery 70 is completed, and when the switch 74 is disposed at the connection position. For example, the operation lamp 76 may be configured to light up in red when the battery 70 is charging, in green when the charging of the battery 70 is completed, and in blue when the switch 74 is disposed at the connection position.

[0051] The casing 50 houses the light source 20, the shaping optical system 30, and the light diffusion element 40. The casing 50 houses the light source 20, the shaping optical system 30, and the light diffusion element 40 so as to emit only the coherent light diffused by the light diffusion element 40. Thereby, the laser safety of the lighting device 10 is improved. In the illustrated example, the casing 50 further houses the battery 70 and the circuit board 72.

[0052] In normal use, the light source 20, the shaping optical system 30, and the light diffusing element 40 are not intended to be removed from the casing 50. For this reason, the light source 20, the shaping optical system 30, and the light diffusing element 40 are fixedly attached to the casing 50 in a non-removable manner. As a result, the relative positions of the light source 20, the shaping optical system 30, and the light diffusing element 40 are maintained at the relative positions determined by the manufacturer of the lighting device 10. Therefore, it is possible to suppress the risk that the light source 20, the shaping optical system 30, and the light diffusing element 40 are displaced from their predetermined positions due to an impact, vibration, or the like transmitted to the lighting device 10. As a result, the illuminated area 90 can be stably illuminated in a predetermined shape. In addition, the risk that coherent light that is not diffused by the light diffusing element 40 is emitted from the lighting device 10 due to the light source 20 or the light diffusing element 40 being displaced from their predetermined positions is suppressed. As a result, the laser safety of the lighting device 10 is improved. In addition, the risk that the light diffusing element 40 is removed from the lighting device 10 by a user or the like of the lighting device 10 is suppressed. This also suppresses the risk that coherent light that is not diffused by the light diffusing element 40 is emitted from the lighting device 10, and improves the laser safety of the lighting device 10. In addition, the risk that the light source 20 is removed from the lighting device 10 by a user or the like of the lighting device 10 and the light source 20 is used for an application not intended by the manufacturer is suppressed.

[0053] Also, in the illustrated example, the casing 50 is composed of a plurality of casing parts 51 to 63. The plurality of casing parts 51 to 63 define a space for accommodating the light source 20, the shaping optical system 30, the light diffusing element 40, the battery 70, and the circuit board 72.

[0054] In the illustrated example, the casing 50 is non-detachable. In other words, the plurality of casing parts 51 to 63 are connected to each other inseparably. This also maintains the relative positions of the light source 20, the shaping optical system 30, and the light diffusing element 40. Specifically, since the casing 50 is non-detachable, the risk that users or the like access the light source 20, the shaping optical system 30, and the light diffusing element 40 housed in the casing 50 is suppressed. As a result, the relative positions of the light source 20, the shaping optical system 30, and the light diffusing element 40 are maintained at the relative positions determined by the manufacturer of the lighting device 10. In addition, the risk that the light diffusing element 40 or the light source 20 is removed from the lighting device 10 by users or the like is suppressed. By maintaining the relative positions of the light source 20, the shaping optical system 30, and the light diffusing element 40, the illuminated area 90 can be stably illuminated in a predetermined shape. In addition, since the risk that the light source 20 or the light diffusing element 40 deviates from a predetermined position or the risk that the light diffusing element 40 is removed from the lighting device 10 is suppressed, the risk that coherent light not diffused by the light diffusing element 40 is emitted from the lighting device 10 is suppressed. Further, the risk that the light source 20 is removed from the lighting device 10 by users or the like of the lighting device 10 and the light source 20 is used for purposes unintended by the manufacturer is suppressed.

[0055] In addition, since the battery 70 and the circuit board 72 are housed in the casing 50, the risk that the battery 70 and the circuit board 72 are damaged due to impacts, vibrations, etc. transmitted to the lighting device 10 is suppressed. In the illustrated example, the battery 70 and the circuit board 72 are fixedly attached to the casing 50 in a non-removable manner. This suppresses the risk that the battery 70 or the circuit board 72 is removed from the lighting device 10 and used for purposes unintended by the manufacturer. Furthermore, since the casing 50 is non-detachable, users or the like cannot access the battery 70 or the circuit board 72 housed in the casing 50. As a result, the risk that the battery 70 or the circuit board 72 is removed from the lighting device 10 by users or the like and used for purposes unintended by the manufacturer can be more effectively suppressed.

[0056] The plurality of casing parts 51 to 63 that constitute the casing 50 may be connected by screwing or fitting. In this case, the casing 50 may be made non-detachable by applying an adhesive to the screwing parts or fitting parts of the casing parts 51 to 63.

[0057] The plurality of casing parts 51 to 63 may be connected watertightly by a sealing material 66. In this case, the waterproof performance of the lighting device 10 can be improved. That is, it is possible to suppress the risk that moisture enters the inside of the lighting device 10 and causes a malfunction in the operation of the lighting device 10. The sealing material 66 may be composed of the above-described adhesive or rubber packing. Further, the sealing material 66 may be formed by applying a water-repellent material or the like to the path entrance where there is a possibility of moisture intrusion.

[0058] With reference to FIGS. 3, 7, and 8, the casing 50 will be described in more detail. In the example shown in FIGS. 3, 7, and 8, the casing 50 includes an outer casing 51 and an inner casing 60 housed in the outer casing 51.

[0059] The inner casing 60 supports the light emitting portion 21 of the light source 20, the shaping optical system 30, and the light diffusing element 40. As shown in FIG. 3, the inner casing 60 has a first end face 60a facing one side in the first direction D1 and a second end face 60b facing the other side in the first direction D1. As shown in FIG. 7, the light diffusing element 40 is fixed to the first end face 60a. As shown in FIG. 3, the lead terminal 22 of the light source 20 extends from the second end face 60b. A battery 70 and a circuit board 72 are housed in a space surrounded by the second end face 60b and the outer casing 51.

[0060] In the illustrated example, the inner casing 60 has a cylindrical portion 61 and a first lid portion 62 and a second lid portion 63 fixed to both ends of the cylindrical portion 61. The first lid portion 62 is connected to the cylindrical portion 61 from the other side in the first direction D1. The second lid portion 63 is connected to the cylindrical portion 61 from one side in the first direction D1.

[0061] The first lid portion 62 has a cylindrical wall portion 62a centered on an axis extending in the first direction D1, and a bottom portion 62b that closes one end of the cylindrical wall portion 62a. The bottom portion 62b closes the end facing the other side of the wall portion 62a in the first direction D1. An opening is provided in the bottom portion 62b. The light source 20 is inserted through the opening. The light emitting portion 21 of the light source 20 is fixed to the surface of the bottom portion 62b facing one side in the first direction D1. In this way, the first lid portion 62 holds the light source 20.

[0062] The cylindrical portion 61 is formed in a cylindrical shape centered on an axis extending in the first direction D1. The end of the cylindrical portion 61 facing the other side in the first direction D1 is accommodated in the first lid portion 62. Therefore, the cylindrical portion 61 accommodates the light emitting portion 21 of the light source 20. Further, the cylindrical portion 61 accommodates the shaping optical system 30.

[0063] As shown in FIG. 3, the inner dimension of the cylindrical portion 61 increases from the upstream side to the downstream side along the optical path of the coherent light emitted from the light source 20. In the illustrated example, three stepped portions 61a are formed on the inner surface of the cylindrical portion 61. The first lens 31, the second lens 32, and the third lens 33 are attached to each of the three stepped portions 61a. A spacer ring 65 capable of precisely controlling the lens interval is provided in the cylindrical portion 61. The spacer ring 65 is disposed between the first lens 31 and the second lens 32. The spacer ring 65 is disposed between the second lens 32 and the third lens 33. Further, a retaining ring 67 is disposed between the second lid portion 63 and the third lens 33. The stepped portion 61a, the spacer ring 65, and the retaining ring 67 suppress the relative displacement of the lenses 31, 32, and 33 due to vibrations, impacts, etc. transmitted to the illumination device 10. That is, according to the stepped portion 61a, the spacer ring 65, and the retaining ring 67, it is possible to suppress the deviation of the parallelism of the collimated light due to the above vibrations, impacts, etc. Thereby, it is possible to suppress the blurring of the illuminated area 90 on the irradiated surface 95. Further, the retaining ring 67 suppresses the relative displacement between the shaping optical system 30 and the light diffusing element 40 due to vibrations, impacts, etc. transmitted to the illumination device 10. Thereby, the illuminated area 90 can be stably illuminated at a predetermined position and in a predetermined shape. Further, the possibility that the light emitted from the shaping optical system 30 is emitted from the illumination device 10 without being diffused by the light diffusing element 40 is suppressed.

[0064] The spacer ring 65 and the retaining ring 67 may be, for example, annular or cylindrical members. As the spacer ring 65 and the retaining ring 67, a metal such as aluminum may be used, or a resin may be used. The resin may be mixed with an inorganic material such as glass fiber in order to reduce the thermal expansion coefficient.

[0065] The second lid portion 63 has a cylindrical wall portion 63a centered on an axis extending along the first direction D1, and a top surface portion 63b that closes one end of the wall portion 63a. The top surface portion 63b closes the end of the wall portion 63a facing one side in the first direction D1. The cylindrical portion 61 is inserted into the second lid portion 63. In the illustrated example, a sealing material 66 is disposed between the wall portion 63a and the outer casing 51. The sealing material 66 extends annularly along the circumferential direction of the outer peripheral surface of the wall portion 63a and the inner peripheral surface of the outer casing 51. Thereby, the risk that moisture enters the outer casing 51 through the gap between the outer casing 51 and the inner casing 60 is suppressed.

[0066] As shown in FIG. 3, an opening 63h through which the light shaped by the shaping optical system 30 passes is provided in the top surface portion 63b. As shown well in FIG. 7, a light diffusing element 40 is fixed to the top surface portion 63b. The light diffusing element 40 is disposed so as to overlap the opening 63h when viewed in the first direction D1. More specifically, a holding portion 64 that holds the edge portion of the light diffusing element 40 is provided on the top surface portion 63b. The holding portion 64 is provided around the opening 63h. Thereby, it is prevented that the light emitted from the light source 20 and passing through the opening 63h and the light diffusing element 40 interferes with the holding portion 64.

[0067] A circumferential sealing material 66 is provided between the top surface portion 63b and the outer casing 51. The sealing material 66 is disposed so as to overlap the boundary portion between the edge portion of the light diffusing element 40 and the top surface portion 63b when viewed in the first direction D1. Thereby, the risk that moisture enters the inner casing 60 through the gap between the light diffusing element 40 and the top surface portion 63b is suppressed.

[0068] The sealing material 66 that seals the boundary portion between the edge portion of the light diffusing element 40 and the top surface portion 63b may also be constituted by an adhesive or a rubber packing. Further, a sealing material 66 that seals the boundary portion between the edge portion of the light diffusing element 40 and the top surface portion 63b may be formed by applying a water repellent material or the like to the boundary portion between the edge portion of the light diffusing element 40 and the top surface portion 63b.

[0069] In order to keep the relative positions of the light source 20, the shaping optical system 30, and the light diffusing element 40 constant, the light source 20, the shaping optical system 30, and the light diffusing element 40 may be fixed to the inner casing 60 by fixing using an adhesive.

[0070] For finely adjusting the relative positions of the light source 20, the shaping optical system 30, and the light diffusing element 40, for example, a spacer may be used. As the spacer, a thin plate-like material made of metal may be used. The spacer may function as a spacer ring 65, an adhesive, or a sealing material 66.

[0071] Also, the light source 20, the shaping optical system 30, and the light diffusing element 40 may be held by a position adjustment holder capable of finely adjusting the arrangement. The position adjustment holder may be able to finely adjust the positions of the light source 20, the shaping optical system 30, and the light diffusing element 40 by operating an adjustment part such as a screw. The light source 20, the shaping optical system 30, and the light diffusing element 40 may be fixed to the casing 50 (inner casing 60 in the illustrated example) via the position adjustment holder. When using the position adjustment holder, after the adjustment of the positions of the components 20, 30, 40 is completed, the adjustment part such as a screw may be fixed with an adhesive or the like. Also, the position adjustment holder may function as a spacer ring 65, an adhesive, or a sealing material 66.

[0072] The outer casing 51 has a first part 52 that houses the inner casing 60 and a second part 56 that houses the battery 70 and the circuit board 72. The first part 52 of the outer casing 51 includes a first cylindrical part 53, a second cylindrical part 54, and a top surface part 55. The first cylindrical part 53 and the second cylindrical part 54 are formed in a cylindrical shape around an axis extending along the first direction D1. The second cylindrical part 54 is connected to the first cylindrical part 53 from one side in the first direction D1.

[0073] The first cylindrical part 53 has a first end part 53a located on one side in the first direction D1 and a second end part 53b located on the other side in the first direction D1. The second cylindrical part 54 has a first end part 54a located on one side in the first direction D1 and a second end part 54b located on the other side in the first direction D1. The first end part 53a of the first cylindrical part 53 is connected to the second end part 54b of the second cylindrical part 54.

[0074] The top surface portion 55 is flat and plate-shaped. The top surface portion 55 is disposed within the second cylindrical portion 54. The top surface portion 55 closes the first end portion 54a of the second cylindrical portion 54. An opening 55h through which the light emitted from the light diffusing element 40 passes is formed in the top surface portion 55.

[0075] The second portion 56 of the outer casing 51 has a first cylindrical portion 57 that houses the battery 70 and a second cylindrical portion 58 that houses the circuit board 72. The first cylindrical portion 57 is formed in a cylindrical shape about an axis extending along the first direction D1. The second cylindrical portion 58 is also formed in a cylindrical shape about an axis extending generally along the first direction D1. The first cylindrical portion 57 has a first end portion 57a located on one side of the first direction D1 and a second end portion 57b located on the other side of the first direction D1. The second cylindrical portion 58 has a first end portion 58a located on one side of the first direction D1 and a second end portion 58b located on the other side of the first direction D1. The first end portion 57a of the first cylindrical portion 57 is connected to the second end portion 58b of the second cylindrical portion 58. The first end portion 58a of the second cylindrical portion 58 is connected to the second end portion 53b of the first cylindrical portion 53 of the first portion 52. The second portion 56 further has a bottom portion 59 that closes the second end portion 57b of the first cylindrical portion 57.

[0076] As can be understood from FIGS. 2 and 3, external connection terminals 71 are fixed to the bottom 59. An external power source can be connected to the external connection terminals 71 from the other side in the first direction D1 of the bottom 59. The bottom 59 may have a cap that covers the external connection terminals 71 from the other side in the first direction D1. In the illustrated example, a strap attachment portion 59h is provided on the bottom 59. The strap attachment portion 59h is, for example, a hole through which a strap can be inserted. By attaching a strap to the strap attachment portion 59h, it becomes easier to carry the lighting device 10. Also, in the illustrated example, anti-rolling means 59r is provided on the bottom 59. The anti-rolling means 59r prevents the lighting device 10 from rolling unintentionally on the plane when the lighting device 10 is placed on the plane. In the illustrated example, the anti-rolling means 59r is a flat surface provided on the outer peripheral surface of the bottom 59. The flat surface as the anti-rolling means 59r extends in a direction intersecting the radial direction of a circle centered on an axis extending along the first direction D1. Note that the anti-rolling means 59r is not limited to a flat surface, and may be a groove, a protrusion, or unevenness provided on the outer peripheral surface of the bottom 59. Alternatively, the anti-rolling means 59r may be a rubber, resin, or cloth material that covers at least a part of the outer peripheral surface of the bottom 59. Such anti-rolling means 59r also functions as an anti-slip means for suppressing the movement of the lighting device 10 within the user's hand when the lighting device 10 is held and used. Note that the anti-rolling means 59r may be provided on the outer peripheral surfaces of other components of the outer casing 51 (in the illustrated example, the first cylindrical portion 53 and the second cylindrical portion 54 of the first portion 52, and the first cylindrical portion 57 and the second cylindrical portion 58 of the second portion 56).

[0077] A battery 70 is non-removably fixed within the first cylindrical portion 57. Within the first cylindrical portion 57, the battery 70 is electrically connected to the external connection terminals 71.

[0078] The second cylindrical portion 58 holds the circuit board 72, the switch 74, and the operation lamp 76. The circuit board 72 is fixedly and non-removably installed within the second cylindrical portion 58. The lead terminal 22 of the light source 20 extends into the second cylindrical portion 58. The lead terminal 22 is electrically connected to the circuit board 72.

[0079] As shown in FIG. 8, the second cylindrical portion 58 is provided with openings 58h and 58i that open in a direction (the third direction D3 in the illustrated example) intersecting the first direction D1. The operation portion 75 of the switch 74 is inserted through the opening 58h. The operation lamp 76 is inserted through the opening 58i. A sealing material 66 for sealing the gap between the operation portion 75 or the operation lamp 76 and the second cylindrical portion 58 is provided within the openings 58h and 58i.

[0080] It should be noted that various modifications can be made to the above-described embodiment.

[0081] As shown in FIG. 9, the lighting device 10 may have a plurality of lighting fixtures 15. In the example shown in FIG. 9, each lighting fixture 15 may have the light source 20, the shaping optical system 30, and the light diffusing element 40 described with reference to FIGS. 3 to 5. In the example shown in FIG. 9, the plurality of lighting fixtures 15 may include light sources 20 that emit coherent light of different wavelengths from each other. In the example shown in FIG. 9, the lighting device 10 has a plurality of light sources 20 and a plurality of light diffusing elements 40 provided corresponding to each light source 20. By the coherent light emitted from each lighting fixture 15 overlapping in the illuminated area 90 on the irradiated surface 95, the illuminated area 90 can be illuminated with a desired color. The lighting device 10 shown in FIG. 9 has first to third lighting fixtures 15A to 15C. Each of the lighting fixtures 15A to 15C separately has light sources 20A to 20C, shaping optical systems 30A to 30C, and light diffusing elements 40A to 40C.

[0082] In the example shown in FIG. 9, the plurality of lighting fixtures 15 may include light sources 20 that emit light of the same wavelength from each other. By the coherent light (illumination light) emitted from each lighting fixture 15 overlapping in the illuminated area 90 of the irradiated surface 95, the illuminated area 90 can be brightly illuminated.

[0083] In the example shown in FIG. 9, the plurality of lighting fixtures 15A to 15C are arranged in the third direction D3. Not limited to the example shown in FIG. 9, the plurality of lighting fixtures 15A to 15C may be arranged, for example, in the second direction D2.

[0084] As shown in FIG. 10, the lighting device 10 may include a scanning device 80. The lighting device 10 shown in FIG. 10 has a plurality of light diffusing elements 40A to 40C. The scanning device 80 adjusts the optical path of the coherent light emitted by the light source 20 to control the presence or absence of the supply of coherent light to the light diffusing element 40 and the distribution of the coherent light to the plurality of light diffusing elements 40A to 40C. The scanning device 80 can be configured using various components such as those that can change the optical path by using refraction, reflection, diffraction, etc. Examples of the various components that can change the optical path include a lens, a prism, a mirror, a diffractive optical element, etc.

[0085] The scanning device 80 changes the optical path of the coherent light from the light source 20 over time. As a result, the incident position of the coherent light on the plurality of light diffusing elements 40A to 40C moves. That is, the light diffusing element 40 on which the coherent light from the light source 20 is incident changes among the plurality of light diffusing elements 40A to 40C. The illustrated scanning device 80 has a reflecting surface that can rotate about a single axis RA. As such a scanning device 80, a galvanometer mirror may be used.

[0086] The illuminated area 90 may be divided into a plurality of sub-areas 93A, 93B, 93C according to the position in the first direction D1. The plurality of light diffusing elements 40A to 40C may illuminate different sub-areas 93A, 93B, 93C. According to this example, the diffraction angle range of the light diffracted by one light diffusing element 40 can be narrowed. Thereby, the diffraction efficiency at each light diffusing element 40 is improved. Note that, by operating the scanning device 80 at a speed exceeding the resolution of human vision, it is observed by humans that all the sub-areas 93A, 93B, 93C included in the illuminated area 90 are continuously illuminated at the same time.

[0087] In the example shown in FIG. 11, the light diffusion element 40 includes first to twelfth light diffusion elements 40A to 40L. For example, the illuminated area 90 on the irradiated surface 95 is divided into first to twelfth partial areas 93A to 93L. The coherent light diffracted by the first to twelfth light diffusion elements 40A to 40L is projected onto separate first to twelfth partial areas 93A to 93L, respectively. The scanning device 80 directs the light from the light source 20 to each of the light diffusion elements 40A to 40L. The illumination device 10 can control the presence or absence of light irradiation to each of the light diffusion elements 40A to 40L according to the operation of the scanning device 80. For example, the light source 20 switches between light emission and emission stop according to the operation of the scanning device 80. As another example, according to the operation of the scanning device 80, a light shielding member that shields light enters and retreats from the optical path of the light from the light source 20. By controlling the presence or absence of light irradiation to each of the light diffusion elements 40A to 40L, coherent light can be projected only onto any of the light diffusion elements 40A to 40L. Thereby, only any of the first to twelfth partial areas 93A to 93L can be illuminated, and it becomes possible to illuminate the inside of the illuminated area 90 in a desired shape.

[0088] Note that the light diffusion element 40 included in the illumination device 10 shown in FIGS. 9 to 11 may be divided into a plurality of element light diffusion elements (element diffractive optical elements) 45.

[0089] Furthermore, the light diffusing element 40 does not have to be a diffractive optical element. For example, the light diffusing element 40 may be a microlens array. The microlens array is formed by arranging a plurality of unit lenses 46 each consisting of a convex lens. The plurality of unit lenses 46 are arranged such that their optical axes are parallel to each other. Also, the plurality of unit lenses 46 are arranged side by side on a virtual plane orthogonal to their optical axes. When the light diffusing element 40 is a microlens array, as shown in FIG. 12, by arranging a mask 47 corresponding to each unit lens 46, the illuminated area 90 can be illuminated in a shape corresponding to the shape of the mask 47. In the illustrated example, the mask 47 is arranged on the downstream side along the optical path of the coherent light emitted from the light source 20 with respect to the light diffusing element 40, but it is not limited to this. The mask 47 may be arranged on the upstream side along the optical path of the coherent light emitted from the light source 20 with respect to the light diffusing element 40, that is, between the shaping optical system 30 and the light diffusing element 40.

[0090] Also, the illumination device 10 does not have to have a battery 70. When the illumination device 10 does not include the battery 70, the illumination device 10 is lightened, and as a result, it is excellent in resistance to vibration and impact. When the illumination device 10 does not include the battery 70, power may be supplied from an external power supply device to the light source 20 via the external connection terminal 71. Even when power is supplied from an external power supply device to the light source 20 via the external connection terminal 71, the casing 50 can be configured to be non-disassemblable. Thereby, the risk of moisture entering the interior of the illumination device 10 is suppressed. Also, the risk that a user or the like of the illumination device 10 accesses the light source 20, the shaping optical system 30, the light diffusing element 40, the circuit board 72, etc. housed in the casing 50 is suppressed.

[0091] The illumination device 10 may have a temperature adjustment mechanism. The temperature adjustment mechanism may maintain the light source 20 and the circuit board 72 at a temperature within a predetermined range. The temperature adjustment mechanism may heat or cool the light source 20 and the circuit board 72. The temperature adjustment mechanism may be installed inside the casing 50. Examples of the temperature adjustment mechanism include a fan, a heater, and a cooler. As the temperature adjustment mechanism, a heating wire, a Peltier element, or the like may be used.

[0092] In one embodiment described above, the lighting device 10 includes a light source 20, a shaping optical system 30, a light diffusion element 40, and a casing 50. The light source 20 emits coherent light. The shaping optical system 30 shapes the coherent light emitted from the light source 20. The light diffusion element 40 diffuses the coherent light shaped by the shaping optical system 30. The casing 50 houses the light source 20, the shaping optical system 30, and the light diffusion element 40. The light source 20, the shaping optical system 30, and the light diffusion element 40 are fixedly and non-removably attached to the casing 50. Thereby, the relative positions of the light source 20, the shaping optical system 30, and the light diffusion element 40 are maintained at the relative positions determined by the manufacturer of the lighting device 10. Therefore, it is possible to suppress the risk that the light source 20, the shaping optical system 30, and the light diffusion element 40 are displaced from their predetermined positions due to the impact or vibration transmitted to the lighting device 10, and the illuminated area 90 can be stably illuminated in a predetermined shape. In addition, the risk that coherent light not diffused by the light diffusion element 40 is emitted from the lighting device 10 is suppressed, and the laser safety can be improved. Further, the risk that the light diffusion element 40 is removed from the lighting device 10 by the user or the like of the lighting device 10 is suppressed. Also, by this, the risk that coherent light not diffused by the light diffusion element 40 is emitted from the lighting device 10 is suppressed, and the laser safety can be improved. Further, the risk that the light source 20 is removed from the lighting device 10 by the user or the like of the lighting device 10 and the light source 20 is used for an application unintended by the manufacturer is suppressed.

[0093] Also, in one embodiment described above, the light diffusion element 40 is a diffractive optical element. Thereby, it becomes possible to illuminate the illuminated area 90 with high precision in a desired shape.

[0094] Also, in one embodiment described above, the light diffusion element 40 may be a microlens array. Also in this case, by using the mask 47, the illuminated area 90 can be illuminated in a desired shape.

[0095] Also, in the embodiment described above, the lighting device 10 further includes a battery 70 that supplies power to the light source 20. The battery 70 is housed in the casing 50 and is non-removably fixed to the casing 50. By housing the battery 70 in the casing 50, the risk that the battery 70 is damaged by the impact or vibration transmitted to the lighting device 10 is suppressed. Also, by non-removably fixing the battery 70 to the casing 50, the risk that the battery 70 is removed from the lighting device 10 and used for purposes unintended by the manufacturer is suppressed.

[0096] Also, in the embodiment described above, the lighting device 10 further includes a secondary battery 70 that supplies power to the light source 20 and an external connection terminal 71 that is detachably connected to an external power supply device. The secondary battery 70 is charged via the external connection terminal 71. In this case, it is not always necessary to remove the battery 70 from the lighting device 10. For this reason, the casing 50 can be configured to be non-disassemblable. Thereby, the risk that moisture enters the interior of the lighting device 10 is suppressed. Also, the risk that a user or the like of the lighting device 10 accesses the light source 20, the shaping optical system 30, the light diffusion element 40, the battery 70, the circuit board 72, etc. housed in the casing 50 is suppressed.

[0097] Also, in the embodiment described above, the lighting device 10 may further include an external connection terminal 71 that is detachably connected to an external power supply device, and power may be supplied from the power supply device to the light source 20 via the external connection terminal 71. In this case, the lighting device 10 may not include the battery 70. When the lighting device 10 does not include the battery 70, the lighting device 10 is lightened, and as a result, it is excellent in resistance to vibration and impact. Also, when power is supplied from an external power supply device to the light source 20 via the external connection terminal 71, the casing 50 can be configured to be non-disassemblable. Thereby, the risk that moisture enters the interior of the lighting device 10 is suppressed. Also, the risk that a user or the like of the lighting device 10 accesses the light source 20, the shaping optical system 30, the light diffusion element 40, the circuit board 72, etc. housed in the casing 50 is suppressed.

[0098] Also, in the embodiment described above, the casing 50 includes a plurality of casing components 51 to 63 that define a space for accommodating the light source 20, the shaping optical system 30, and the light diffusing element 40. The plurality of casing components 51 to 63 are inseparably connected to each other. Thereby, the risk of moisture entering the inside of the casing 50 is suppressed. Further, the risk that a user or the like of the lighting device 10 accesses the light source 20, the shaping optical system 30, the light diffusing element 40, the battery 70, the circuit board 72, etc. accommodated in the casing 50 is suppressed.

[0099] Also, in the embodiment described above, the plurality of casing components 51 to 63 are connected via a sealing material 66. Thereby, the risk of moisture entering the inside of the casing 50 is suppressed.

[0100] Also, in the embodiment described above, the lighting device 10 further includes a circuit board 72 that is electrically connected to the light source 20. The casing 50 accommodates the circuit board 72. Thereby, the risk that the circuit board 72 is damaged by the impact or vibration transmitted to the lighting device 10 is suppressed.

[0101] Also, in the embodiment described above, the light diffusing element 40 has an incident surface 41 on which the light from the shaping optical system 30 is incident, and irregularities for diffusing the light from the shaping optical system 30 are formed on the incident surface 41. Thereby, the risk that the light diffusing element 40 is damaged and the above-mentioned irregularities are missing is suppressed. As a result, the light from the shaping optical system 30 can be reliably diffused by the light diffusing element 40.

[0102] Also, in the embodiment described above, the light diffusing element 40 has an exit surface 42 through which the light incident on the incident surface 41 exits. The above-mentioned irregularities of the light diffusing element 40 are formed over the entire region of the incident surface 41 that overlaps at least the exit surface 42 when viewed in the direction from the exit surface 42 to the incident surface 41 of the light diffusing element 40. Thereby, the risk that non-diffused coherent light is emitted from the light diffusing element 40 is suppressed.

[0103] Also, in the embodiment described above, only the light diffused by the light diffusion element 40 is emitted. Thereby, the laser safety of the lighting device 10 is improved.

[0104] Also, in the embodiment described above, anti-rolling means 59r is provided on the outer peripheral surface of the casing 50. Thereby, when the lighting device 10 is placed on a flat surface, the risk that the lighting device 10 rolls unintentionally on the flat surface can be suppressed.

[0105] Although an embodiment has been described above with reference to specific examples, the embodiment is not limited by the specific examples. The above-described embodiment can be implemented with various other specific examples, and various omissions, replacements, changes, additions, etc. can be made without departing from the gist thereof.

Description of Reference Numerals

[0106] 10: Lighting device, 20: Light source, 21: Light emitting portion, 22: Lead terminal, 30: Shaping optical system, 31: First lens, 32: Second lens, 33: Third lens, 40: Light diffusion element, 41: Incident surface, 42: Exit surface, 45: Element diffractive optical element, 50: Casing, 51: Outer casing, 60: Inner casing, 70: Battery, 71: External connection terminal, 76: Operation lamp, 72: Circuit board, 74: Switch, 90: Illuminated area, 95: Irradiated surface, D1: First direction, D2: Second direction, D3: Third direction

Claims

1. A light source that emits coherent light, A shaping optical system that shapes the coherent light emitted from the light source, A light diffusing element that diffuses the coherent light shaped by the shaping optical system, A casing that houses the light source, the shaping optical system, and the light diffusing element, and The light source, the shaping optical system, and the light diffusing element are fixedly attached to the casing in a non-removable manner, The casing includes a plurality of casing components that define a space for housing the light source, the shaping optical system, and the light diffusing element, The plurality of casing components are connected to each other in a non-separable manner. A lighting device.

2. The lighting device according to claim 1, wherein the light diffusing element is a diffractive optical element.

3. The lighting device according to claim 1, wherein the light diffusing element is a microlens array.

4. Further comprising a battery that supplies power to the light source, The battery is housed in the casing and is fixedly attached to the casing in a non-removable manner. The lighting device according to any one of claims 1 to 3.

5. A secondary battery that supplies power to the light source, and An external connection terminal that is detachably connected to an external power supply device, and The secondary battery is charged via the external connection terminal. The lighting device according to any one of claims 1 to 4.

6. Further comprising an external connection terminal that is detachably connected to an external power supply device, Power is supplied from the power supply device to the light source via the external connection terminal. The lighting device according to any one of claims 1 to 4.

7. The lighting device according to any one of claims 1 to 6, wherein the plurality of casing components are connected via a sealing material.

8. Further comprising a circuit board that is electrically connected to the light source, The casing houses the circuit board. The lighting device according to any one of claims 1 to 7.

9. The light diffusing element has an incident surface on which light from the shaping optical system is incident, The lighting device according to any one of claims 1 to 8, wherein irregularities for diffusing the light from the shaping optical system are formed on the incident surface.

10. The light diffusing element has an exit surface from which the light incident on the incident surface exits, The lighting device according to claim 9, wherein the irregularities are formed over the entire region of at least the area of the incident surface that overlaps the exit surface when the light diffusing element is viewed in a direction from the exit surface toward the incident surface.

11. The lighting device according to claim 10, which emits only the light diffused by the light diffusing element.

12. The lighting device according to any one of claims 1 to 11, wherein anti-rolling means is provided on an outer peripheral surface of the casing.

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