This application claims the benefit of priority of Japanese Patent Application Number 2016-204482 filed on Oct. 18, 2016, the entire content of which is hereby incorporated by reference.
The present disclosure relates to lighting apparatuses to which an optical fiber is attached.
Conventionally, there are lighting apparatuses that illuminate by causing phosphor to emit light using laser light guided by an optical fiber as excitation light, and converting the emitted light into light of a desired color. For example, Japanese Unexamined Patent Application Publication No. 2013-149449 (Patent Literature 1) describes a technique related to such a lighting apparatus. The phosphor described in Patent Literature 1 is provided with a heat sink that dissipates heat generated by the phosphor.
In order to enhance efficiency of light color conversion by the phosphor, the positioning of the phosphor and the optical fiber need to be carried out precisely, but in the assembly of the lighting apparatus, there are cases where the positioning work is complicated. Furthermore, after the positioning, there is a desire that the optical fiber be stably secured at their determined positions.
In addition, when the phosphor is provided with a heat sink, the heat sink can only be made to a size that is dependent on the phosphor, and thus, in actuality, there is a restriction in the heat-dissipation amount.
In view of this, the present disclosure provides a lighting apparatus that enables simplification and stabilization of optical fiber positioning while increasing heat-dissipation amount.
A lighting apparatus that wavelength-converts laser light guided by an optical fiber to output light having a different wavelength as the laser light, and includes: a holder that holds the optical fiber; a wavelength converter that wavelength-converts the laser light emitted from the optical fiber; and a case that is made of metal, holds the wavelength converter, and houses the holder. The holder includes a main body and a flange, the main body having a lead end face from which the laser light is emitted, the flange projecting from an outer circumferential face of a base end of the main body. The case has a through hole penetrating from one end face to another end face of the case, and the wavelength converter is attached to the case to be coaxial with the through hole. The through hole of the case houses the main body of the holder, and has an abutting face which the lead end face of the main body abuts. The flange of the holder is secured to the case in a state where the lead end face of the main body abuts the abutting face.
The present disclosure provides a lighting apparatus that enables simplification and stabilization of optical fiber positioning while increasing heat-dissipation amount.
The figures depict one or more implementations in accordance with the present teaching, by way of examples only, not by way of limitations. In the figures, like reference numerals refer to the same or similar elements.
Hereinafter, lighting apparatuses according to exemplary embodiments of the present disclosure will be described with reference to the drawings. It should be noted that each of the subsequently-described exemplary embodiments shows a specific example. Therefore, numerical values, shapes, materials, structural components, the arrangement and connection of the structural components, etc. shown in the following exemplary embodiments are mere examples, and are not intended to limit the scope of the present disclosure. Furthermore, among the structural components in the following exemplary embodiments, components not recited in any one of the independent claims which indicate the broadest concepts of the present disclosure are described as arbitrary structural components.
Furthermore, the respective figures are schematic diagrams and are not necessarily precise illustrations. In addition, in the respective diagrams, identical structural components are given the same reference signs.
Hereinafter, lighting apparatus 1 according to an exemplary embodiment of the present disclosure will be described with reference to the drawings.
First, the configuration of lighting apparatus 1 will be described.
As illustrated in
[Holder]
Holder 2 is a component that holds optical fibers 10. Specifically, holder 2 includes first component 21 and second component 22, and optical fibers 10 are held when first component 21 and second component 22 are in an attached state. In this embodiment, a pair of optical fibers 10 arranged side-by-side in the radial direction are held in holder 2 in the state where optical fibers 10 are housed inside protective tube 11. It should be noted that the number of optical fibers 10 collectively held by holder 2 may be one or three or more. Furthermore, laser light beams emitted by a light emitter (for example, a semiconductor laser diode that outputs short-wavelength light of at least 500 nm) not illustrated in the figures enter from base end faces of the pair of optical fibers 10. The laser light beams guided by optical fibers 10 are emitted from lead end faces (light emission faces) of optical fibers 10.
[First Component]
As illustrated in
Furthermore, optical fibers 10 are disposed, together with protective tube 11, inside holding hole 215. Screw hole 216 running along the radial direction of main body 211 is formed in main body 211 so as to connect with holding hole 215. By screwing set screw 217 in screw hole 216 so as to pin down protective tube 11 using set screw 217, the pair of optical fibers 10 and protective tube 11 can be secured inside holding hole 215.
Flange 212 projects from the outer circumferential face of the base end of main body 211, and runs continuously over the entire circumference. It should be noted that flange 212 may project intermittently from the outer circumferential face of the base end of main body 211, and may provided in only a portion of the outer circumferential face of the base end of main body 211. In addition, a pair of securing holes 250 are formed parallel to the axis direction in flange 212, at opposing positions across main body 211. Securing holes 250 are holes for attaching case 4 to first component 21 using first screws 260. Specifically, each of securing holes 250 includes first shaft hole 253 which is disposed on the lead end-side of flange 212 and into which shaft 261 of first screw 260 is inserted, and first counterbore 254 which is disposed on the base end-side of flange 212 to connect with first shaft hole 253, and inside of which head 262 of first screw 260 is housed. First counterbores 254 are formed in the shape of circles with larger diameters than first shaft holes 253.
As illustrated in
On the other hand, screw holes 99 corresponding to respective securing holes 270 are formed in support 90. When screw holes 99 and securing holes 270 of first component 21 are aligned, and second screws 280 are inserted into securing holes 270 and screwed into screw holes 99, first component 21 is secured to support 90.
[Second Component]
As illustrated in
[Wavelength Converter]
As illustrated in
Substrate 31 holds fluorescent portion 32 and is, for example, an annular substrate. A plurality of insertion holes 34 for securing substrate 31 to case 4 via screws 33 are formed in the periphery of substrate 31, at predetermined intervals in the circumferential direction.
Fluorescent portion 32 is attached to substrate 31 to cover the hole at the center of substrate 31. Fluorescent portion 32 includes, in a dispersed state, particles of phosphor that emits fluorescence when excited by laser light, for example, and the phosphor emits fluorescence when irradiated with laser light. Specifically, fluorescent portion 32 can be exemplified as a component in which phosphor particles are dispersed inside a base material comprising a transparent resin or glass, or a component in which phosphor particles are packed tightly together, etc.
In this embodiment, fluorescent portion 32 radiates white light, and includes, in an appropriate ratio, two types of phosphors: red phosphor that emits red light and yellow phosphor that emits yellow light, when irradiated with laser light. Furthermore, fluorescent portion 32 may include three types of phosphors: red phosphor that emits red light, blue phosphor that emits blue light, and green phosphor that emits green light, when irradiated with laser light.
Although there is no particular limitation as to the type or characteristics of the phosphors, it is desirable for the phosphors to have high heat resistance since laser light having a comparatively high output serves as the excitation light. Furthermore, although there is no particular limitation as to the type of the base material which holds the phosphors in a dispersed state, it is desirable to have a base material with higher transparency because white light radiation efficiency also improves. Furthermore, since laser light with comparatively high output will be entering, a base material with high heat resistance is desirable.
[Case]
Case 4 is a housing formed from a metal with a high heat dissipation property such as an Fe-based alloy (SUS, SF material, etc.) or a Cu-based alloy (brass, etc.). As illustrated in
Holder 2 is housed inside case 4. Specifically, through hole 41 is formed at the center of the lead end face of case 4, along the axis direction. Through hole 41 penetrates from the lead end face up to the base end face of case 4. Holder 2 is housed inside through hole 41. Wavelength converter 3 is disposed coaxially with through hole 41. It should be noted that although the case where wavelength converter 3 covers through hole 41 from the outside of through hole 41 is given as an example in this embodiment, it is sufficient that wavelength converter 3 be disposed coaxially with through hole 41. In other words, wavelength converter 3 need not cover through hole 41, and may be disposed inside through hole 41.
Through hole 41 is formed into a shape having an inner circumference that decreases in stages (monotonic decrease) from the base end side (first end face) to the lead end face (second end face) of case 4. Specifically, through hole 41 includes, sequentially from the lead end side, small-diameter portion 411, medium-diameter portion 412, and large-diameter portion 413. Small-diameter portion 411, medium-diameter portion 412, and large-diameter portion 413 are coaxially-disposed columnar holes.
Small-diameter portion 411 serves as an optical path that guides the laser light beams emitted from optical fibers 10 up to fluorescent portion 32 of wavelength converter 3. Stated differently, the light emission faces of optical fibers 10 held in holder 2 are located opposite fluorescent portion 32 of wavelength converter 3, via small-diameter portion 411.
Holder 2 is housed in medium-diameter portion 412 and large-diameter portion 413. Specifically, main body 211 of first component 21 of holder 2 and second component 22 are housed in medium-diameter portion 412, and flange 212 of first component 21 is housed in large-diameter portion 413.
Medium-diameter portion 412 is a first portion into which main body 211 of holder 2 is fitted together with second component 22. Specifically, the inner diameter of medium-diameter portion 412 is formed into a size for fitting the columnar portion formed by the attachment of main body 211 of first portion 21 and second component 22. This fitting determines the position of holder 2 in the direction orthogonal to the axis direction, and thus also determines the position, in the direction orthogonal to the axis direction, of optical fibers 10 held in holder 2.
Furthermore, a lead end-side bottom face of medium-diameter 412 is abutting face 45 which each of lead end face of first component 21 and the leading end face of second component 22 of holder 2 abuts. By having the lead end face of first component 21 and the lead end of second component 22 abut abutting face 45, positioning of the light emission faces of optical fibers 10 held in holder 2 can be carried out. The interval between abutting face 45 and fluorescent portion 32 is set to a length which enables appropriate positioning of the light emission faces of optical fibers 10 held in holder 2 with respect to fluorescent portion 32.
Large-diameter portion 413 is a second portion that is disposed further on the base end-side than medium-diameter portion 412, and is formed into a shape for housing flange 212. Since the entirety of holder 2 fits inside case 4 when flange 212 is housed inside large-diameter portion 413, the external appearance can be made to impart a neat impression.
Furthermore, a plurality of first screw holes 46 with which respective securing holes 250 of flange 212 are aligned in a straight line are formed in a lead end-side bottom face of large-diameter 413. When shafts 261 of first screws 260 are screwed into first screw holes 46 via securing holes 250 of flange 212 housed in large-diameter portion 413, holder 2 is secured to case 4. Since heads 262 of first screws 260 are housed in first counterbores 254 of securing holes 250 after the securing, the entirety of first screws 260 fits inside case 4, and deterioration of aesthetic appearance of lighting apparatus 1 as a whole is suppressed.
[Lens]
As illustrated in
[Lens Holder]
As illustrated in
Holding member 62 is a substantially cylindrical component formed from metal or resin, inside of which lens 5 is housed. The lead end of holding member 62 abuts projection 51 of lens 5. Specifically, when exterior body 61 is screwed onto case 4 in the state where lens 5 and holding member 62 are housed inside exterior body 61, projection 51 of lens 5 is held between the lead end of holding member 62 and projection 64 of exterior body 61. Accordingly, positioning of lens 5 is carried out.
Next, the method of assembling lighting apparatus 1 will be described.
From the state illustrated in
On the other hand, the pair of optical fibers 10 are attached to first component 21 of holder 2 via protective tube 11. Specifically, the pair of optical fibers 10 and protective tube 11 are inserted into holding hole 215 of first component 21. At this time, the lead ends of the pair of optical fibers 10 are pulled out from protective tube 11 and fitted into groove 213 of first component 21. Next, by screwing set screw 217 into screw hole 216 of first component 21, the pair of optical fibers 10 and protective tube 11 are secured inside holding hole 215.
Subsequently, second component 22 is attached to first component 21. Specifically, as illustrated in
Here, before holder 2 is attached to case 4, first component 21 of holder 2 is attached to support 90 for supporting lighting apparatus 1. Specifically, as illustrated in
Next, as illustrated in
Subsequently, holder 2 is secured to case 4. Specifically, when securing holes 250 of first component 21 and first screw holes 46 of case 4 are aligned, and first screws 260 are inserted inside securing holes 250 and screwed in first screw holes 46, holder 2 is secured to case 4. After the securing, heads 262 of first screws 260 are housed inside first counterbores 254 and do not protrude from first component 21. After assembly, lighting apparatus 1 assumes the state illustrated in
As described above, according to this embodiment, lighting apparatus 1 is a lighting apparatus that wavelength-converts laser light guided by optical fibers 10 to output light having a different wavelength as the laser light. Lighting apparatus 1 includes holder 2 that holds optical fibers 10, wavelength converter 3 that wavelength-converts the laser light emitted from optical fibers 10, and case 4 that is made of metal, holds wavelength converter 3, and houses holder 2. Holder 2 includes main body 211 having a lead end face from which the laser light is emitted, and flange 212 projecting from the outer circumferential face of the base end of main body 211. Case 4 has through hole 41 which penetrates from one end face to another end face of the case, and wavelength converter 3 is attached to case 4 on the same axis as through hole 41. Through hole 41 of case 4 houses main body 211 of holder 2 therein, and has abutting face 45 which main body 211 abuts. Flange 212 of holder 2 is secured to case 4 in a state where the lead end face of main body 211 abuts abutting face 45.
Accordingly, by causing the lead end face of main body 211 of holder 2 to abut abutting face 45 of case 4, the relative positioning of wavelength converter 3 attached to case 4 and optical fibers 10 held by holder 2 can be carried out. In other words, by merely causing the lead end face of main body 211 of holder 2 to abut abutting face 45 of case 4 when holder 2 is attached to case 4, positioning of optical fibers 10 can be carried out. Furthermore, by securing flange 212 of holder 2 to case 4 after the positioning, the position of optical fibers 10 is stabilized.
On the other hand, since wavelength converter 3 is directly held in case 4, the heat generated by wavelength converter 3 is dissipated to the outside via case 4. Since the size of case 4 can be determined independently of fluorescent portion 32 of wavelength converter 3, the heat-dissipation amount can be increased compared to the conventional case where the phosphor is provided with a heat sink.
Accordingly, it is possible to simplify and stabilize the positioning of optical fiber 10 while increasing heat-dissipation amount.
Furthermore, through hole 41 has medium-diameter portion 412 (first portion) having a shape that accommodates fitting of main body 211 of holder 2.
Accordingly, since main body 211 of holder 2 is fitted into medium-diameter portion 412 of through hole 41, the position of holder 2 in the direction orthogonal to the axis direction can be determined. Therefore, it is also possible to determine the position in the direction orthogonal to the axis direction for optical fibers 10 held in holder 2.
Furthermore, through hole 41 has large-diameter portion 413 (second portion) located closer to the base end side than medium-diameter portion 412 is and having a shape that accommodates housing of flange 212 of holder 2.
Accordingly, the presence of large-diameter portion 413 enables the surface area of case 4 to be enlarged compared to when large-diameter portion 413 is not present in case 4. Therefore, the heat-dissipation amount of case 4 can be increased.
In addition, since the entirety of holder 2 fits inside case 4 when flange 212 is housed inside large-diameter portion 413, the external appearance can be made to impart a neat impression.
Furthermore, flange 212 of holder 2 has: first shaft hole 253 which is disposed on the lead end-side of flange 212 and into which shaft 261 of first screw 260 is inserted; and first counterbore 254 which is disposed on the base end-side of flange 212 to connect to first shaft hole 253, and inside which head 262 of first screw 260 is housed. Case 4 has, in a portion located opposite large-diameter portion 413, first screw hole 46 into which shaft 261 of first screw 260 that has been inserted through first counterbore 254 and first shaft hole 253 is screwed.
Accordingly, holder 2 can be screw-fastened to case 4 using first screws 260. In addition, since heads 262 of first screws 260 are housed in first counterbores 254 of securing holes 250 after the screw-fastening, the entirety of first screws 260 fits inside case 4, and thus deterioration of aesthetic appearance of lighting apparatus 1 as a whole is suppressed.
Furthermore, flange 212 of holder 2 has: second shaft hole 273 which is disposed on the base end-side of flange 212 and into which shaft 281 of second screw 280 is inserted; and second counterbore 274 which is disposed on the lead end-side of flange 212 to connect with second shaft hole 273, and inside which head 282 of second screw 280 is housed. Shaft 281 of second screw 280 that has been inserted through second counterbore 274 and second shaft hole 273 is screwed into support 90 for supporting light apparatus 1.
Accordingly, holder 2 can be screw-fastened to support 90 using second screws 280. Then, after the screw-fastening, heads 282 of second screws 280 are housed inside second counterbores 274 and do not protrude from flange 212. Accordingly, the attaching structures between lighting apparatus 1 and support 90 are not exposed to the outside, and thus aesthetic appearance can be improved.
(Variation 1)
In the foregoing embodiment, the case where groove 213 into which optical fibers 10 are fitted is formed only in first component 21 is given as an example. In Variation 1, the case where groove 223a is also formed in second component 22a is given as an example.
It should be noted that, in the subsequent description, the same reference signs are given to components that are the same as in the foregoing embodiment, and there are instances where their description is omitted.
As illustrated in
(Variation 2)
In the foregoing embodiment, the case where optical fibers 10 are held by first component 21 and second component 22 is given as an example. In Variation 2, the case where optical fibers 10 are held by a pair of boards 91 and 92 which are separate components from first component 21b will be described.
As illustrated in
Board 91 is a rectangular board that is placed on the flat portion of first portion 216b, and a linear groove 911 is formed on one major surface of board 91. When board 91 is disposed at a predetermined position on the flat portion of first portion 216b, groove 911 is aligned in a straight line with holding hole 215. The first ends of the pair of optical fibers 10 are collectively fitted inside groove 911. Furthermore, a pair of insertion holes 912 connected to the pair of screw holes 218b are formed in board 91.
Board 92 is a rectangular board disposed on top of the major surface of board 91. Board 92 is a pressing component that pins down the first ends of the pair of optical fibers 10 fitted in groove 911. A pair of securing holes 920 are formed in board 92, corresponding to insertion holes 912 of board 91. Securing holes 920 are holes for attaching boards 91 and 92 to first portion 216b, using screws 295. Specifically, each of securing holes 920 includes shaft hole 921 into which shaft 296 of screw 295 is inserted, and counterbore 922 which is connected to shaft hole 921 and inside of which head 297 of screw 295 is housed. When screws 295 are inserted into securing holes 920 of board 92 and insertion holes 912 of board 91 and screwed into screw holes 218b of first portion 216b, the pair of boards 91 and 92 are secured to first portion 216b. Then, as illustrated in
(Variation 3)
In the foregoing embodiment, the case where flange 212 of holder 2 is housed inside case 4 is given as an example. In Variation 3, the case where flange 212 is not housed in case 4 is given as an example.
As illustrated in
(Variation 4)
In the foregoing embodiment, the case where optical fibers 10 are held in holder 2 is given as an example. In Variation 4, the case where optical fiber 10 is held in holder 2d via ferrule 100 will be given as an example. It should be noted that in lighting apparatus 1D according to Variation 4, a single optical fiber 10 is held in holder 2d.
As illustrated in
Screw hole 235 is formed in the outer circumferential face of main body 211d, penetrating along the radial direction of main body 211d up to hole 219 so as to connect to hole 219. By screwing set screw 236 in screw hole 235 so as to pin down ferrule 100 using set screw 236, ferrule 100 and optical fiber 10 can be secured inside holding hole 219. With this securing the lead end faces of ferrule 100 and optical fiber 10 are flush with the lead end face of main body 211d. In this manner, even in the case where ferrule 100 is attached to optical fiber 10, by causing the lead end face of main body 211d of holder 2 to abut abutting face 45 of case 4, the relative positioning of wavelength converter 3 and optical fiber 10 can be carried out.
(Others)
Although lighting apparatuses according to the present disclosure are described thus far based on the foregoing exemplary embodiment and variations thereof, the present disclosure is not limited to the foregoing exemplary embodiment and variations thereof.
For example, in the foregoing embodiment, case 4 is exemplified as having a substantially cylindrical shape but may be of any shape as long it is tubular. A substantially square tube shape can be given as another shape for case 4. Furthermore, holder 2 may also be of any shape as long as it is a shape that can be housed inside through hole 41 of case 4.
Furthermore, in the foregoing embodiment, the case where a plurality of optical fibers 10 are fitted into one groove 213 is given as an example. However, a plurality of grooves may be formed in the holder and one optical fiber may be fitted in each of the grooves.
Furthermore, in the foregoing embodiment, the case where flange 212 of holder 2 is screw-fastened to case 4 is given as an example. However, the method of securing flange 212 to case 4 may be any method. Securing by interfitting or securing by adhesives, etc., may be given as other securing methods. It should be noted that when flange 212 of holder 2 is detachably secured to case 4, workability during maintenance can be enhanced.
Forms obtained by various modifications to the exemplary embodiments that can be conceived by a person of skill in the art as well as forms realized by arbitrarily combining structural components and functions in the respective exemplary embodiment which are within the scope of the essence of the present disclosure are included in the present disclosure.
Number | Date | Country | Kind |
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2016-204482 | Oct 2016 | JP | national |