Lighting device

Abstract

To provide a lighting device the light distribution part of which can be reduced in weight.SOLUTION: A lighting device 10 includes: a light-emitting part 20; a light-distributing part 30 disposed at a position apart from the light-emitting part and emitting light emitted by the light-emitting part as illumination light having a prescribed light distribution; and a light guide part 40 guiding the light emitted by the light-emitting part to the inside of the light distribution part. The light distribution part is a hollow body the inner surface of which is a reflection surface, and includes at least one emission port 33 for controlling the light guided to its inside by the light guide part.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a lighting device. [Background technology]

[0002] 2. Description of the Related Art Conventionally, there has been known an illumination device that integrally includes a light-emitting unit (light source) and a light distribution unit (light guide unit) that controls light distribution by guiding light emitted from the light-emitting unit (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2019-192554 A Summary of the Invention [Problem to be solved by the invention]

[0004] In recent years, there has been a demand for lighter lighting devices.

[0005] An object of the present invention is to provide a lighting device that can reduce the weight of the light distribution section by separating the light emitting section and the light distribution section. [Means for solving the problem]

[0006] An illumination device according to one aspect of the present invention includes a light-emitting unit, a light distribution unit arranged at a position away from the light-emitting unit and emitting light emitted by the light-emitting unit as illumination light with a predetermined light distribution, and a light guiding unit that guides the light emitted by the light-emitting unit to an inside of the light distribution unit, wherein the light distribution unit is a hollow body whose inner surface is a reflective surface and has one or more emission openings for controlling the light guided into the interior by the light guiding unit to the predetermined light distribution. Effect of the Invention

[0007] According to the present invention, by providing the light emitting section and the light distribution section as separate bodies, it is possible to provide a lighting device that can reduce the weight of the light distribution section. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a perspective view showing a schematic configuration of an illumination device according to an embodiment. [Diagram 2] FIG. 2 is a perspective view showing a schematic configuration of a light distribution section and a light guide section according to the embodiment. [Diagram 3] FIG. 3 is a cross-sectional view showing a schematic configuration of a light distribution section and a light guide section according to the embodiment. [Figure 4] FIG. 4 is a schematic cross-sectional view showing the optical action of the lighting device according to the embodiment. [Diagram 5] FIG. 5 is a perspective view showing an illumination device according to the first modification. [Figure 6] FIG. 6 is a perspective view showing an illumination device according to the second modification. [Figure 7] FIG. 7 is a plan view showing a holding portion according to the second modification. [Figure 8] FIG. 8 is a perspective view showing an illumination device according to the third modification. [Figure 9] FIG. 9 is a perspective view showing an illumination device according to the fourth modification. [Figure 10] FIG. 10 is a perspective view showing an illumination device according to the fourth modification. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] In the following, a lighting device according to an embodiment of the present invention will be described with reference to the drawings. Note that each of the embodiments described below shows a preferred specific example of the present invention. Therefore, the numerical values, shapes, materials, components, arrangements and connection forms of the components shown in the following embodiments are merely examples and are not intended to limit the present invention. Therefore, among the components in the following embodiments, components that are not described in the independent claims showing the highest concept of the present invention will be described as optional components.

[0010] In addition, each drawing is a schematic diagram and is not necessarily a precise illustration. In addition, in each drawing, the same components are denoted by the same reference numerals.

[0011] [Embodiment Mode] An embodiment will be described below. Fig. 1 is a perspective view showing a schematic configuration of a lighting device 10 according to the embodiment. As shown in Fig. 1, the lighting device 10 is a hanging type lighting device, and includes a light-emitting unit 20, a light distribution unit 30, a light guide unit 40, and an outer shell 50.

[0012] The light-emitting unit 20 is disposed above and away from the light distribution unit 30, the light guiding unit 40, and the outer shell 50. The light-emitting unit 20 is a laser element that generates laser light whose emission peak wavelength is included in the blue wavelength band. The light-emitting unit 20 is disposed in a position that allows it to irradiate laser light downward. A power supply unit that supplies power to the light-emitting unit 20 is installed, for example, in the ceiling. In other words, since the power supply unit and the light-emitting unit 20 are disposed in a location separate from the light distribution unit 30, the light guiding unit 40, and the outer shell 50, the weight of the light distribution unit 30 can be reduced.

[0013] The light distribution unit 30 is a part that receives light from the light emitting unit 20, converts the wavelength of the light, and emits it as illumination light with a predetermined light distribution. The light distribution unit 30 is housed within the outer shell 50.

[0014] Fig. 2 is a perspective view showing a schematic configuration of the light distribution section 30 and the light guide section 40 according to the embodiment. Fig. 3 is a cross-sectional view showing a schematic configuration of the light distribution section 30 and the light guide section 40 according to the embodiment.

[0015] 2 and 3, the light distribution unit 30 is a hollow solid body. In the present embodiment, the light distribution unit 30 has an outer shape of a truncated octahedron, but the outer shape of the light distribution unit 30 may be any shape.

[0016] Among the first surfaces 31 having a rectangular shape in plan view in the light distribution section 30, the first surface 31a at the top is formed with a light guide section 40. The light guide section 40 is an opening having a circular shape in plan view, and is a portion that receives light from the light emitting section 20 into the light distribution section 30. The light guide section 40 may have any shape in plan view as long as it receives light from the light emitting section 20 into the light distribution section 30, and may be covered with a translucent member. In addition, among the first surfaces 31 in the light distribution section 30, the first surface 31b at the bottom is formed with a plurality of exit ports 33. In the first surface 31b, the plurality of exit ports 33 are arranged along multiple circles. Among the first surfaces 31 in the light distribution section 30, the first surface 31c other than the first surfaces 31a and 31b is a flat surface without an opening.

[0017] In the light distribution section 30, a plurality of second surfaces 32 each having a hexagonal shape in a plan view are each formed with a plurality of light exit ports 33. In each second surface 32, the plurality of light exit ports 33 are arranged along multiple circles.

[0018] In this embodiment, each light exit port 33 is a circular opening when viewed from above, but as long as light can be emitted to the outside from the light distribution section 30, its shape when viewed from above may be any shape, and it may be covered with a translucent material.

[0019] As shown in Fig. 3, inside the light distribution section 30, a protruding section 34 is formed that protrudes from the inner bottom surface in a conical or prismatic shape. The protruding section 34 is disposed at a position facing the light guiding section 40. Here, since the light distribution section 30 is formed from, for example, a white resin plate, the inner surface of the light distribution section 30 and the outer surface of the protruding section 34 are configured to reflect light. Note that the portions of the light distribution section 30 other than the light guiding section 40 and each exit port 33 may be non-translucent or may be translucent with a transmittance of 5% or less.

[0020] In addition, a fluorescent layer 35 is laminated on the inner surface of the light distribution section 30 and the outer surface of the protrusion 34. The fluorescent layer 35 may be laminated on at least a part of the inner surface of the light distribution section 30 and the outer surface of the protrusion 34, but in this embodiment, it is laminated on the entire inner surface of the light distribution section 30 and the outer surface of the protrusion 34. This allows the light taken into the light distribution section 30 and the reflected light to be more reliably directed to the fluorescent layer 35.

[0021] The fluorescent layer 35 includes a plurality of phosphor particles in a dispersed state, which are excited by light (laser light) incident from the light emitting unit 20 into the light distribution unit 30 and emit fluorescence. That is, the phosphor emits fluorescence when irradiated with laser light. Specifically, the fluorescent layer 35 may be a layer in which phosphor particles are dispersed inside a base material made of transparent resin or glass, or a layer in which phosphor particles are solidified. In the present embodiment, the fluorescent layer 35 emits white light. That is, the fluorescent layer 35 converts laser light into light of a longer wavelength band. The type and characteristics of the phosphor are not particularly limited, but since a relatively high-output laser light serves as the excitation light, it is desirable that the phosphor has high heat resistance and does not cause luminance saturation. For example, an yttrium aluminum garnet (YAG) phosphor is used. The type of base material that holds the phosphor in a dispersed state is not particularly limited, but if the transparency is high, the yellow light emission efficiency is also high, so it is preferable. In addition, since a relatively high-output laser light is incident, a material with high heat resistance is preferable.

[0022] As described above, since the protrusion 34 is disposed at a position facing the light guide 40, the laser light received from the light guide 40 into the light distribution section 30 is reflected by the protrusion 34 and diffused inside the light distribution section 30. When reflected, the laser light hits the fluorescent layer 35 on the protrusion 34 and is wavelength-converted to white light. In other words, the laser light is prevented from being emitted outside the light distribution section 30 as it is.

[0023] The wavelength-converted light is reflected by the inner surface of the light distribution unit 30 and the outer surface of the protrusion 34, and is emitted from each exit 33 to the outside of the light distribution unit 30. Here, the size, shape, and installation location of each exit 33 are determined in advance so that the light distribution distribution of the illumination light emitted from each exit 33 becomes a predetermined light distribution distribution. In other words, if the size, shape, and installation location of each exit 33 are determined so as to obtain a desired light distribution distribution when the lighting device 10 is designed, it is possible to control the light emitted from each exit 33 to a desired light distribution distribution. The size, shape, and installation location of each exit 33 can be determined by various experiments, simulations, empirical rules, and the like. The light distribution may include a light distribution pattern, a light distribution angle, and the like. In this embodiment, the light distribution distribution is such that the total light distribution based on the light distribution unit 30 can be realized.

[0024] As shown in FIG. 1, the outer shell 50 is a cover that houses the light distribution section 30 and the light guide section 40. The outer shell 50 is formed of a resin, paper, glass, or the like having light diffusion properties. As a result, the light emitted from the light distribution section 30 is diffused by the outer shell 50 and emitted to the outside of the outer shell 50. The outer shell 50 is a hollow spherical body, and an opening 51 that is circular in plan view and receives laser light from the light emitting section 20 is formed in the upper part of the outer shell 50. The opening 51 exposes the light guide section 40. A plurality of wires 52 whose upper ends are fixed to the ceiling are attached to the periphery of the opening 51. In addition, a plurality of wires 53 whose lower ends are fixed to the light distribution section 30 are attached to the periphery of the opening 51. The outer shape of the outer shell 50 is not limited to a spherical shape and may be any shape. Other possible shapes of the outer shell 50 include, for example, an ellipsoidal sphere, a cylinder, an ellipsoidal cylinder, a polygonal prism, a regular polyhedron, and a three-dimensional star.

[0025] FIG. 4 is a schematic cross-sectional view showing the optical action of the lighting device 10 according to the embodiment. In FIG. 4, the protrusion 34 of the light distribution section 30 is omitted. As shown in FIG. 4, the laser light emitted from the light emitting section 20 passes through the opening 51 of the outer shell 50 and the light guide section 40 of the light distribution section 30, and is received in the light distribution section 30. In the light distribution section 30, the laser light is reflected by the outer surface of the protrusion 34 and the inner surface of the light distribution section 30, and is wavelength-converted to white light by the fluorescent layer 35, and is then emitted from each exit 33 to the outside of the light distribution section 30. In this way, the white light is reflected by the outer surface of the protrusion 34 and the inner surface of the light distribution section 30 to reach at least one exit 33, and is emitted from the exit 33. In other words, the white light can reach each exit 33 by reflecting inside the light distribution section 30, so that the light distribution is more reliably controlled to a predetermined light distribution. The white light emitted from each outlet 33 is diffused by the outer shell 50 and emitted to the outside of the outer shell 50.

[0026] [Effects, etc.] As described above, the lighting device 10 according to this embodiment comprises a light-emitting unit 20, a light distribution unit 30 that is arranged at a position away from the light-emitting unit 20 and emits the light emitted by the light-emitting unit 20 as illumination light with a predetermined light distribution, and a light-guiding unit 40 that guides the light emitted by the light-emitting unit 20 to the inside of the light distribution unit 30. The light distribution unit 30 is a hollow body whose inner surface is a reflective surface, and has one or more emission openings 33 for controlling the light guided inside by the light-guiding unit 40 to a predetermined light distribution.

[0027] According to this, since the light emitting unit 20 is disposed at a position away from the light distribution unit 30, the light emitting unit 20 and the light distribution unit 30 can be separated. This allows the light emitting unit 20 and the power source connected thereto to be installed in separate locations from the light distribution unit 30. In other words, the light distribution unit 30 can be made lighter.

[0028] Here, when the power source, the light emitting unit, and the light distribution unit are integrated into a lighting device, the installation location is determined in order to secure a power supply source. In contrast, if the light emitting unit and the power source can be installed in separate locations from the light distribution unit 30 as in this embodiment, it is possible to increase the freedom of the installation location of the light distribution unit 30.

[0029] In particular, in this embodiment, the inner surface of the light distribution section 30 is a reflective surface. Therefore, the light from the light emitting section 20 is guided from the light guiding section 40 into the light distribution section 30, and then is reflected by the inner surface of the light distribution section 30 to reach each outlet 33. In other words, no matter where at least one or more outlets 33 for controlling the predetermined light distribution are located, the light can be guided to the outlet 33 by repeatedly reflecting the light by the inner surface of the light distribution section 30. Therefore, the predetermined light distribution can be more reliably realized.

[0030] Since the outer shell 50, which has light diffusing properties and contains the light distribution section 30, exposes the light guide section 40, the light from the light emitting section 20 can be guided to the light guide section 40. The light guided by the light guide section 40 is controlled to a predetermined light distribution by the light distribution section 30, and then emitted while being diffused by the outer shell 50. This allows for illumination without a grainy feel.

[0031] Since the fluorescent layer 35 is laminated on the inner surface of the light distribution section 30, the light from the light emitting section 20 can be wavelength-converted by the fluorescent layer 35 simply by reflecting the light on the inner surface of the light distribution section 30. In addition, since there is no need to provide a separate dedicated member for wavelength conversion, the number of parts can be reduced.

[0032] [Variations] Next, a modified example of the present embodiment will be described. In the following description, the same parts as those in the above embodiment will be denoted by the same reference numerals, and the description thereof will be omitted in some cases.

[0033] Fig. 5 is a perspective view showing an illumination device 10A according to Modification 1. An outer shell 50 is not shown in Fig. 5. As shown in Fig. 5, a light guide unit 40a of the illumination device 10A includes an opening 41a, a lens 42a, and a holder 43a.

[0034] The opening 41a is a circular opening in plan view formed on the first surface 31a at the top of the light distribution unit 30, and is a portion that receives the laser light from the light emitting unit 20 into the light distribution unit 30. The lens 42a is a lens disposed between the light emitting unit 20 and the light distribution unit 30. The holding unit 43a is a portion that supports the lens 42a. The holding unit 43a has a first arm 431a whose base is fixed to the outer surface of the light distribution unit 30, and a second arm 432a that is attached to the first arm 431a so as to be slidable. The second arm 432a holds the lens 42a so that it can move freely and its posture can be changed freely. That is, the position and posture of the lens 42a can be adjusted. By adjusting the position and posture of the lens 42a, it is possible to reliably guide the laser light from the light emitting unit 20 to the opening 41a.

[0035] In this manner, since the light guiding section 40a is provided with the lens 42a, it is possible to guide the laser light into the light distribution section 30 by the lens 42a.

[0036] In particular, since the position and attitude of lens 42a relative to the laser light emitted by light-emitting unit 20 can be adjusted by holder 43a, the laser light can be guided into light distribution unit 30 more reliably.

[0037] Fig. 6 is a perspective view showing an illumination device 10B according to Modification 2. An outer shell 50 is not shown in Fig. 6. As shown in Fig. 6, a light guide unit 40b of the illumination device 10B includes an opening 41b, a lens 42b, and a holder 43b.

[0038] Opening 41b is a circular opening in plan view formed in first surface 31a at the top of light distribution unit 30, and is a portion that receives laser light from light emitter 20 into light distribution unit 30. Lens 42b is a lens disposed between light emitter 20 and light distribution unit 30. A pair of shaft bodies 421b aligned in a straight line are attached to lens 42b (see FIG. 7).

[0039] The holding portion 43b is a portion that holds the attitude of the lens 42b so as to be freely variable. FIG. 7 is a plan view showing the holding portion 43b according to the second modification. As shown in FIG. 7, the holding portion 43b is a double-frame arrangement of a first frame body 431b and a second frame body 432b. The first frame body 431b is arranged inside the second frame body 432b. A pair of shaft bodies 421b of the lens 42b is slidably and rotatably attached to the first frame body 431b. In addition, a pair of shaft bodies 433b extending in a direction perpendicular to the pair of shaft bodies 421b of the lens 42b is attached to the first frame body 431b. The pair of shaft bodies 433b is slidably and rotatably attached to the second frame body 432b. As a result, the position and attitude of the lens 42b are adjusted by rotating the shaft bodies 421b and 433b.

[0040] In this way, since the position and attitude of the lens 42b with respect to the laser light emitted by the light emitting unit 20 can be adjusted by the holding unit 43b, the laser light can be guided into the light distribution unit 30 more reliably.

[0041] Fig. 8 is a perspective view showing an illumination device 10C according to Modification Example 3. In Fig. 8, the outer shell 50 is omitted. As shown in Fig. 8, a light guide section 40c of the illumination device 10C includes an opening 41c and a mirror pipe 44c. In Fig. 8, the mirror pipe 44c is shown in a cross-sectional perspective view.

[0042] The opening 41c is a circular opening in a plan view formed on the first surface 31a at the top of the light distribution unit 30, and is a portion that receives the laser light from the light-emitting unit 20 into the light distribution unit 30. The mirror pipe 44c is an optical member that guides the laser light from the light-emitting unit 20 into the opening 41c. Specifically, the mirror pipe 44c is a cylinder with both ends open, and the laser light is reflected by its inner surface. The mirror pipe 44c is fixed to the first surface 31a at the top of the light distribution unit 30, and surrounds the opening 41c.

[0043] In this manner, since the light guiding section 40c includes the mirror pipe 44c, it is possible to guide the laser light into the light distribution section 30 by the mirror pipe 44c.

[0044] Fig. 9 is a perspective view showing an illumination device 10D according to Modification 4. In Fig. 9, outer shell 50 is not shown. As shown in Fig. 9, light guiding section 40d of illumination device 10D includes opening 41d and light guiding rod 45d. In Fig. 9, light guiding rod 45d is shown in a cross-sectional perspective view.

[0045] Opening 41d is a circular opening in plan view formed on first surface 31a at the top of light distribution section 30, and is a portion that receives laser light from light-emitting section 20 into light distribution section 30. Light-guiding rod 45d is a light-guiding member that guides laser light from light-emitting section 20 into opening 41c. Specifically, light-guiding rod 45d is a solid rod body that guides laser light received from one end surface to the other end surface while totally reflecting the laser light, and then emits the light. Light-guiding rod 45d is fixed to first surface 31a at the top of light distribution section 30, and covers opening 41c.

[0046] In this manner, since light guiding section 40d includes light guiding rod 45d, it is possible to guide the laser light into light distribution section 30 by light guiding rod 45d.

[0047] Fig. 10 is a perspective view showing an illumination device 10E according to Modification 5. As shown in Fig. 10, a light guide 40e of the illumination device 10E includes an opening 41e and an optical fiber 46e. In Fig. 10, a part of the outer shell 50 is not shown.

[0048] The opening 41e is a circular opening in a plan view formed on the first surface 31a at the top of the light distribution unit 30, and is a portion that receives the laser light from the light emitter 20 into the light distribution unit 30. The optical fiber 46e is disposed such that one end corresponds to the opening 51 of the outer shell 50, and the other end corresponds to the opening 41e. The optical fiber 46e emits the laser light received from one end from the other end and guides it into the light distribution unit 30.

[0049] In this manner, since the light guide unit 40e includes the optical fiber 46e, it is possible to guide the laser light into the light distribution unit 30 by the optical fiber 46e.

[0050] [others] Although the lighting device according to the present invention has been described based on the above embodiment and modifications, the present invention is not limited to the above embodiment and modifications.

[0051] In the above embodiment, the lighting device 10 having the outer shell 50 is exemplified, but the lighting device may not have an outer shell.

[0052] In the above embodiment, the fluorescent layer 35 is laminated on the inner surface of the light distribution section 30, but the fluorescent section may be disposed in any location as long as it can convert the wavelength of the laser light.

[0053] In the above embodiment, the light emitting unit 20 is a laser element. However, it is also possible to use other light sources as the light emitting unit. Examples of other light sources include LEDs.

[0054] In addition, in the above embodiment, the hanging type lighting device 10 is exemplified, but a lighting device other than the hanging type may be used. Examples of other lighting devices include a fixed type lighting device in which a light distribution unit is fixed to a ceiling, wall, or floor, and a floating type lighting device in which a light distribution unit floats in the air by a drone or magnetism.

[0055] In addition, the present invention also includes forms obtained by applying various modifications to the embodiments that a person skilled in the art may think of, and forms realized by arbitrarily combining the components and functions of each embodiment without departing from the spirit of the present invention.

[0056] An example of the lighting device according to the present invention described based on the above embodiment will be shown below, but the lighting device according to the present invention is not limited to the following example.

[0057] For example, a lighting device of Technology 1 includes a light-emitting unit, a light distribution unit that is arranged at a position away from the light-emitting unit and outputs the light emitted by the light-emitting unit as illumination light with a predetermined light distribution, and a light guiding unit that guides the light emitted by the light-emitting unit to the inside of the light distribution unit, the light distribution unit being a hollow body whose inner surface is a reflective surface and having one or more light exits for controlling the light guided to the inside by the light guiding unit to a predetermined light distribution.

[0058] A second technique relates to the lighting device according to the first technique, and further includes an outer shell having light diffusivity and housing the light distribution section, the outer shell exposing the light guide section.

[0059] Technique 3 provides the lighting device according to technique 1 or 2, in which the light guide portion includes a lens.

[0060] Technique 4 provides the lighting device according to technique 3, wherein the light guiding section has a holder for adjusting at least one of a position and an attitude of the lens relative to the light emitted by the light emitting section.

[0061] Technique 5 provides the lighting device according to technique 1 or 2, in which the light guiding section includes a mirror pipe.

[0062] Technique 6 provides the lighting device according to Technique 1 or Technique 2, in which the light guiding section includes a light guiding rod.

[0063] Technique 7 provides the lighting device according to Technique 1 or Technique 2, in which the light guide includes an optical fiber.

[0064] Technique 8 provides the lighting device according to any one of Techniques 1 to 7, in which a phosphor layer is laminated on an inner surface of the light distribution section. [Explanation of symbols]

[0065] 10, 10A, 10B, 10C, 10D, 10E lighting equipment 20 Light emitting part 30 Light distribution section 33 Exit port 35 Fluorescent Layer 40, 40a, 40b, 40c, 40d, 40e light guide 42a, 42b Lenses 43a, 43b Holding part 44c Mirror Pipe 45d Light guide rod 46e Optical Fiber 50 Shell

Claims

1. A light emitting portion; a light distribution unit that is disposed at a position away from the light emitting unit and that outputs the light emitted by the light emitting unit as illumination light with a predetermined light distribution; A light guide unit that guides the light emitted by the light emitting unit to an inside of the light distribution unit, The light distribution unit is a hollow body whose inner surface is a reflective surface, and has one or more exit ports for controlling the light guided into the interior by the light guiding unit to a predetermined light distribution. Lighting equipment.

2. An outer shell having a light diffusing property and accommodating the light distribution section, The outer shell exposes the light guiding portion.

10. The lighting device of claim 1.

3. The light guide comprises a lens.

3. The lighting device according to claim 1 or 2.

4. The light guide unit has a holder for adjusting at least one of a position and an attitude of the lens relative to the light emitted by the light emitting unit.

4. The lighting device according to claim 3.

5. The light guiding section includes a mirror pipe.

3. The lighting device according to claim 1 or 2.

6. The light guiding portion includes a light guiding rod.

3. The lighting device according to claim 1 or 2.

7. The light guide comprises an optical fiber.

3. The lighting device according to claim 1 or 2.

8. A fluorescent layer is laminated on the inner surface of the light distribution section.

3. The lighting device according to claim 1 or 2.

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