JP2022036140A - Light-emitting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a light-emitting device and the like reducing breakage by thermal stress.

SOLUTION: A light-emitting device 100 includes: a light diffusion part 30 which is composed of a material different from a cylindrical pipe part 20 arranged so as to surround an arrangement region on a substrate 10, diffuses and transmits light emitted by a plurality of light emitting elements; and a cover part 40 which is fixed on the substrate 10 and holds the light diffusion part 30 between itself and the pipe part 20. The light diffusion part 30 is arranged on an upper surface of the pipe part 20. The cover part 40 is provided with: a cover region 41 which has an internal diameter larger than an outer diameter of the pipe part 20 and covers an outside surface of the pipe part 20; and a holding region 42 which is extended from an upper end of the cover region 41 to an inside, has an inner diameter smaller than an outer diameter of the light diffusion part 30, and covers an upper end of the light diffusion part 30. The cover part is formed so that difference in height between an arrangement position of the light diffusion part 30 on an upper surface of the pipe part 20 and a lower surface of the holding region 42 becomes greater than thickness of the light diffusion part 30, and a thickness direction margin MV is formed between the holding region 42 and the light diffusion part 30.

SELECTED DRAWING: Figure 4

COPYRIGHT: (C)2022,JPO&INPIT

Description

The present invention relates to a light emitting device.

A light emitting device using a light emitting element such as a light emitting diode (LED) is used for lighting or the like. Some such light emitting devices use a large number of LED chips in order to increase the amount of light.

However, if the light emitted by a large number of LED chips is output as it is, the outer shape of each LED chip may be visually recognized due to the strong directivity of the LED light. For example, in the case of a light emitting element in which square LED chips are arranged in a grid pattern, a grid pattern may appear as the output light of the LED.

Therefore, it is conceivable to provide a diffusion optical system for diffusing and emitting light emitted from the LED chip. For example, it is conceivable to use a light emitting device 110 provided with a diffused optical system composed of a tubular light guide pipe 111 as shown in FIG. 11 and a diffused glass 130 bonded to the light guide pipe 111.

However, when a large number of LED chips are arranged intensively, it is conceivable that the amount of heat generated will increase. For example, in the configuration of FIG. 11, when the light guide pipe 111 is made of resin, a difference in linear expansion coefficient occurs between the light guide pipe 111 and the diffused glass 130. That is, at high temperatures, the amount of deformation of the resin light guide pipe 111 becomes large, while the diffuser glass 130 hardly expands, and as a result, the light guide pipe 111 expands at the junction interface between the light guide pipe 111 and the diffuser glass 130. As a result of being pushed back to the diffused glass 130 by the reaction, the light guide pipe 111 made of resin may be damaged. As described above, when the diffusion optical system is integrally molded, there is a problem that damage due to thermal stress occurs.

Japanese Unexamined Patent Publication No. 2001-108878 Jikkenhei 03-092614 Gazette Japanese Unexamined Patent Publication No. 10-319873 Japanese Unexamined Patent Publication No. 2006-178382

The present invention has been made in view of such a background, and one of the objects thereof is to provide a light emitting device in which damage due to thermal stress is reduced.

According to the light emitting device according to one embodiment of the present invention, a plurality of light emitting elements, a substrate provided with an arrangement area for arranging the plurality of light emitting elements in a predetermined pattern on the upper surface, and the substrate are fixed to the substrate. A tubular pipe portion arranged so as to surround the arrangement region on the substrate, a light diffusion portion made of a material different from the pipe portion and diffusing and transmitting light emitted by the plurality of light emitting elements, and the substrate. The light diffusing portion is provided with a cover portion that is fixed to and holds the light diffusing portion between the pipe portion, the light diffusing portion is arranged on the upper surface of the pipe portion, and the cover portion is the pipe portion. It has an inner diameter larger than the outer diameter and has an inner diameter that covers the outer surface of the pipe portion and an inner diameter that extends inward from the upper end of the covering region and is smaller than the outer diameter of the light diffusing portion. A holding region covering the upper end of the light diffusing portion is provided, and the difference in height between the arrangement position of the light diffusing portion on the upper surface of the pipe portion and the lower surface of the holding region is larger than the thickness of the light diffusing portion. A thickness direction margin is formed between the holding region and the light diffusing portion.

According to the above embodiment, it is possible to obtain a light emitting device with reduced damage due to thermal stress.

It is a side view of the lighting apparatus which concerns on Embodiment 1. FIG. It is an exploded perspective view which removed the reflector from the lighting apparatus of FIG. It is an enlarged perspective view of the light emitting device of FIG. It is an exploded perspective view of the light emitting device of FIG. FIG. 3 is an exploded perspective view of the light emitting device of FIG. 4 as viewed from diagonally below. FIG. 3 is a cross-sectional view taken along the line VI-VI of FIG. FIG. 6 is an enlarged step view of a main part of FIG. FIG. 8A is an example of an arrangement pattern of light emitting elements, and FIG. 8B is a plan view showing another example. It is a perspective view which shows the cover part which concerns on the modification. 10A and 10B are enlarged cross-sectional views showing an example of the inner surface of the holding region. It is a perspective view which shows the light emitting device provided with the diffusion optical system prototyped by the present inventors.

Hereinafter, embodiments and examples according to the present invention will be described with reference to the drawings. However, the embodiments and examples shown below are examples for embodying the technical idea of the present invention, and the present invention is not limited to the following. In addition, the size and positional relationship of the members shown in each drawing may be exaggerated to clarify the explanation. Further, in the following description, members of the same or the same quality are shown with the same name and reference numeral, and detailed description thereof will be omitted as appropriate. Further, each element constituting the embodiment and the embodiment according to the present invention may be configured such that a plurality of elements are composed of the same member and the plurality of elements are combined with one member, or conversely, one member. It is also possible to share the functions of the above with a plurality of members. In addition, the contents described in some examples and embodiments can be used in other embodiments and embodiments.
(Lighting device)

1 to 7 show the lighting device 1000 according to the first embodiment. Here, as an example of a light emitting device, an example applied to a medical lighting device is shown. In these figures, FIG. 1 is a side view of the lighting device 1000 according to the first embodiment, FIG. 2 is an exploded perspective view in which the reflector 50 is removed from the lighting device 1000 of FIG. 1, and FIG. 3 is a light emitting device 100 of FIG. An enlarged perspective view, FIG. 4 is an exploded perspective view of the light emitting device 100 of FIG. 3, FIG. 5 is an exploded perspective view of the light emitting device 100 of FIG. 4 as viewed from diagonally below, and FIG. 6 is a sectional view taken along line VI-VI of FIG. , FIG. 7 shows an enlarged step view of a main part of FIG. 6, respectively. In the lighting device 1000 shown in FIGS. 1 and 2, a reflector 50 is provided in the light emitting device 100. The reflector 50 is fixed to a light emitting surface that emits light emitted from the light emitting device 100, and the light that has entered the inside of the reflector 50 from the light emitting device 100 is reflected by the reflecting surface. The reflector 50 constitutes a collimated optical system that brings the light from the light emitting device 100 closer to parallel light. Further, instead of the reflector 50, a lens may be used as the above optical system. In addition, a reflective surface having excellent reflection efficiency is formed on the end surface. The reflective surface is preferably made of metal. The reflector does not necessarily have to be a separate member, and may be integrally configured with the light emitting device. Further, the reflector is not essential and can be omitted.
(Light emitting device 100)

The light emitting device 100 shown in FIGS. 3, 4, and 5 has a plurality of light emitting elements 1, a substrate 10 on which the plurality of light emitting elements 1 are mounted, and a cylinder arranged so as to surround the light emitting element 1 on the substrate 10. A pipe portion 20 having a shape, a light diffusing portion 30 fixed to the upper surface of the pipe portion 20, and a cover portion 40 having the light diffusing portion 30 sandwiched between the pipe portions 20 and fixed to the substrate 10 are provided.
(Light emitting element 1)

A light emitting diode is usually used as the light emitting element 1. The light emitting element 1 can be appropriately selected depending on the purpose, such as its composition, light emitting color or wavelength, size, number, and the like. For example, as the blue and green light emitting elements, a semiconductor layer such as ZnSe, a nitride semiconductor (In _X Al _Y Ga _1-XY N, 0 ≦ X, 0 ≦ Y, X + Y ≦ 1), GaP or the like is used. Examples of the red light emitting element include those using a semiconductor layer such as GaAlAs and AlInGaP.

The light emitting element 1 is usually formed by laminating a semiconductor layer on a growth substrate (for example, a sapphire substrate). The growth substrate may have irregularities on the bonding surface with the semiconductor layer. As a result, the critical angle when the light emitted from the semiconductor layer hits the growth substrate is intentionally changed, and the light can be easily taken out to the outside of the growth substrate. The growth substrate may be removed after the semiconductor layers are laminated. The growth substrate can be removed by, for example, polishing, LLO (Laser Lift Off), or the like.

The light emitting element 1 may have a pair of positive and negative electrodes on the same surface side. Thereby, the light emitting element 1 can be flip-chip mounted on the conductive pattern formed in advance in the arrangement region on the substrate 10. In this case, the surface facing the surface on which the pair of electrodes is formed becomes the light extraction surface. Flip-chip mounting uses metal bumps such as Au and Cu, a paste-like bonding member having conductivity such as solder, a thin-film bonding member, and the like, and the conductive pattern of the light emitting element 1 and the substrate 10 is electrically connected. Be connected. Alternatively, in the case of face-up mounting, the surface on which the pair of electrodes are formed may be used as the light extraction surface. Alternatively, the light emitting element may have a pair of positive and negative electrodes on different sides. In this case, one electrode is adhered to the substrate 10 with a conductive adhesive, and the other electrode is connected to the substrate 10 with a conductive wire or the like.

Further, the light emitting element may be combined with a phosphor that absorbs the light emitted from the light emitting element 1 and converts the wavelength into light having a different wavelength. As the phosphor, those known in the art can be used. For example, yttrium-aluminum-garnet phosphor (YAG: Ce) activated with cerium, lutetium-aluminum-garnet phosphor (LAG: Ce) activated with cerium, europium and / or nitrogen activated with chromium. Contains calcium aluminosilicate-based phosphor (CaO-Al ₂ O ₃ -SiO ₂ : Eu, Cr), europium-activated silicate-based phosphor ((Sr, Ba) ₂ SiO ₄ : Eu), β-sialon phosphor, Chlorosilicate phosphors, nitride-based phosphors such as CASN-based or SCASN-based phosphors, rare earth metal nitride phosphors, oxynitride phosphors, KSF-based phosphors (K ₂ SiF ₆ : Mn), sulfide-based phosphors Examples include a body and a quantum dot phosphor. By combining these phosphors with a blue light emitting element or an ultraviolet light emitting element, a light emitting device of various colors (for example, a white light emitting device) can be obtained. When a light emitting device capable of emitting white light using a blue light emitting element is used, the light emitting device is adjusted to be white depending on the type and concentration of the phosphor covering the light emitting element.

A plurality of light emitting elements 1 are included in one light emitting device 100. The plurality of light emitting elements 1 are arranged in an aligned manner. For example, they may be arranged in one column or may be arranged in a plurality of columns. The number of light emitting elements 1 can be appropriately set according to the characteristics, size, and the like of the light emitting device to be obtained.

It is preferable that the plurality of light emitting elements 1 to be aligned are close to each other, and further, considering the luminance distribution and the like, the distance between the light emitting elements is about 5 to 50% of the length of the maximum side of the light emitting element 1. It is preferably about 5 to 30%, more preferably about 5 to 20%. By arranging the light emitting elements close to each other in this way, a uniform and good luminance distribution can be ensured. As a result, it is possible to obtain a light emitting device 10 of a surface light source having low light emission unevenness and high light emission quality.

Further, the plurality of light emitting elements 1 may be configured by combining different light emitting colors. For example, a first light emitting element 1a that emits a first light emitting color and a second light emitting element 1b having a light emitting color different from the first light emitting element are included. Specifically, a light bulb-colored light-emitting diode and a white light-emitting diode can be combined.

Further, in the example of FIG. 4 and the like, a plurality of light emitting elements 1 are arranged in a circular shape. At this time, various patterns can be adopted as the arrangement pattern when arranging the plurality of different types of light emitting elements 1. For example, as shown in FIG. 8A, light emitting elements 1 of the same type, for example, the first light emitting element 1a and the second light emitting element 1b are arranged linearly and alternately arranged. Alternatively, as shown in FIG. 8B, light emitting elements of the same type may be arranged in a wavy shape instead of a linear shape. In the example of FIG. 8B, a gentle V-shaped pattern whose center is recessed with respect to the horizontal direction is alternately arranged for each line. By alternately arranging such non-linear curves for each of the same type of light emitting elements, the color mixing property is higher than that of the pattern in which the same type of light emitting elements arranged in a straight line are alternately arranged as shown in FIG. 8A. Can be increased.
(Board 10)

The substrate 10 is a mounting substrate on which a plurality of light emitting elements 1 are arranged in a predetermined pattern and mounted on the upper surface. The substrate 10 usually consists of a conductive pattern and a substrate that supports it. Examples of the material of the substrate include a substrate made of an insulating material such as glass epoxy, resin, and ceramics, and a metal member such as aluminum on which the insulating material is formed. Among them, those using ceramics having high heat resistance and weather resistance are preferable. Examples of ceramics include alumina, aluminum nitride, and mullite. Insulating materials such as BT resin, glass epoxy, and epoxy resin may be combined with these ceramics. The thickness of the substrate is, for example, about 100 μm to 1 mm. An arrangement region for arranging a plurality of light emitting elements 1 is formed on the substrate 10.
(Pipe part 20)

The pipe portion 20 is fixed on the substrate 10 so as to surround the arrangement area. Further, the inner surface of the pipe portion 20 is a member having enhanced light reflectivity. For example, it can be a white resin, a metal-plated resin, or a metal cylinder. When the pipe portion 20 is made of a resin, polycarbonate, polystyrene, acrylic nitrile-butadiene-styrene resin (ABS resin), polyvinyl chloride resin, polyethylene terephthalate, polybutylene terephthalate, polypropylene and the like can be used. In particular, polybutylene terephthalate is preferable in terms of strength. By surrounding the periphery of the plurality of light emitting elements 1 in a cylindrical shape in this way, the pipe portion 20 can be used as a light guide tube (light guide) for guiding light. Specifically, the shape of the pipe portion 20 is a cylinder with both ends open. Then, one opening is used as an introduction end for introducing light, and the other opening is used as an emission end for emitting light. Further, the introduction end is arranged on the substrate 10 side, and the light diffusing portion 30 is arranged at the emission end. In this way, by separating the light diffusing plate from the light emitting element 1 which is a light source by the pipe portion 20, it is possible to secure the optical path length and enhance the light diffusing effect.

The end face of the tubular pipe portion 20 has an annular shape. However, the cylindrical end face is not limited to an annular shape, and may be an elliptical shape, a rectangular shape, a polygonal shape, or the like. Further, the pipe portion 20 has a first pipe region 21 and a second pipe region 22. The first pipe region 21 has a first inner diameter D1 smaller than the outer diameter of the light diffusing portion 30. The second pipe region 22 has a second inner diameter D2 larger than the first inner diameter D1 above the first pipe region 21. Further, the height H2 of the second pipe region 22 is formed higher than the thickness H3 of the light diffusing portion 30 described later. The difference between the thickness H3 of the light diffusing portion 30 and the height H2 of the second pipe region 22 is the thickness direction margin MV described later.

On the other hand, the first pipe region 21 has a recess 23 formed at the lower end of the inner wall thereof, which is higher than the thickness of the light emitting element 1. In the example shown in the exploded perspective view of FIG. 5 and the cross-sectional view of FIG. 6, the recessed portion 23 is formed by chamfering the edge of the light guide end of the pipe portion 20 or scraping it off in a stepped manner. By forming such a recessed portion 23, when the pipe portion 20 is fixed on the substrate 10 at the time of assembling the light emitting device 100, the possibility that the inner wall of the pipe portion 20 comes into contact with the light emitting device 100 can be reduced, and the light emitting element 1 can be reduced. Is protected.

Further, it is preferable that the height HP of the pipe portion 20 is formed smaller than the inner diameter of the pipe, specifically, the second inner diameter D2. As a result, the light diffusing plate is separated from the plurality of light emitting elements 1 by the pipe portion 20 to secure the optical path length, but the optical path length becomes long and the light is reflected and absorbed in the pipe portion 20 to reduce the efficiency. It is possible to suppress the situation.
(Pipe side base area 24)

Further, the pipe portion 20 includes a pipe-side base region 24 for fixing to the substrate 10 extending outward from the lower end of the first pipe region 21. A plurality of pipe-side base regions 24 are preferably provided. The plurality of pipe-side base regions 24 are arranged around the pipe portion 20 at equal intervals. In the examples of FIGS. 4 and 5, three pipe-side base regions 24 are arranged at intervals of about 120 ° in a plan view. Further, on the back surface side of each pipe-side base region 24, that is, on the surface in contact with the substrate 10, a pipe-side pin 25 is provided at the tip thereof as a pipe-side fixing portion as shown in FIG. Further, on the substrate 10 side, when the pipe portion 20 is arranged in a posture surrounding the arrangement area, the substrate side first pin hole 15 is opened as the substrate side first fixing portion at a position corresponding to the pipe side pin 25. .. The pipe side pin 25 is fitted into the substrate side first pin hole 15, and the pipe portion 20 is fixed on the substrate 10. In the present invention, the structure for fixing the pipe portion to the substrate is not limited to the fitting of the pin and the pin hole, and other known fixing methods such as screwing with screws or bolts, caulking, bonding and the like can be appropriately used.
(Light diffuser 30)

The light diffusing unit 30 is a member for diffusing and transmitting the light emitted by the plurality of light emitting elements 1. Such a light diffusing unit 30 has light permeability and has both sides or one side roughened, or disperses a diffusing material that diffuses light. Further, the light diffusing portion 30 is made of a material different from that of the pipe portion 20. For example, by forming the light diffusing portion 30 with a glass plate having excellent heat resistance and light resistance, its deterioration can be suppressed. In particular, if a light emitting element that irradiates strong light such as an LED is used, it will be exposed to strong light. When a plurality of LEDs are used, the light becomes even stronger. In addition, the amount of heat generated by the plurality of light emitting elements increases accordingly. Therefore, the light diffusing portion 30 is required to have high durability such as light resistance and heat resistance, and an inorganic material is preferable to an organic resin material.

The light diffusing portion 30 is arranged inside the second pipe region 22 and at the upper end of the first pipe region 21. By providing the pipe portion 20 as the light guide tube and the light diffusing portion 30 at the emission end in this way, the light emitted by the plurality of light emitting elements 1 can be mixed relatively uniformly, and the quality is high with little unevenness. It becomes possible to obtain a light emitting device.

Examples of the material constituting the light diffusing unit 30 include glass materials such as silicate glass, borosilicate glass, and quartz glass. As a method of roughening both sides or one side of the light diffusing portion 30, sandblasting, polishing or the like can be used.

Further, the light diffusing unit 30 may have a phosphor or the like in addition to the diffusing material. The diffusing material or the fluorescent substance may be contained inside the light diffusing section 30, or a layer containing the diffusing material or the fluorescent substance may be provided on both sides or one side of the light diffusing section 30. As a method for forming a layer containing a diffuser or a phosphor, for example, a printing method, a spray method, an electrodeposition method, or an electrostatic coating method can be used. Alternatively, a fluorescent material sheet or the like made of a material containing a fluorescent material in a resin may be adhered to the light diffusing portion.

As the diffusing material, for example, silica, titanium oxide, zirconium oxide, aluminum oxide and the like can be used.
(Cover 40)

The cover portion 40 is a member for holding the light diffusing portion 30 between the light diffusing portion 30 and the pipe portion 20. The cover portion 40 is fixed to the substrate 10. The cover portion 40 includes a covering region 41, a holding region 42, and a cover-side base region 43. The cover portion 40 is made of polycarbonate, polystyrene, acrylonitrile-butadiene-styrene resin (ABS resin), polyvinyl chloride resin, polyethylene terephthalate, polybutylene terephthalate, polypropylene and the like. Preferably, it is composed of the same member as the pipe portion 20.
(Covered area 41)

The covering region 41 of the cover portion 40 is formed in a cylindrical shape having an inner diameter larger than the outer diameter of the pipe portion 20. The covering region 41 is formed according to the shape of the pipe portion 20, and when the pipe portion 20 is formed in a cylindrical shape, the covering region 41 is formed in a cylindrical shape slightly larger than this. The outer surface of the pipe portion 20 is covered with the covering region 41.
(Holding area 42)

The holding region 42 extends inward from the upper end of the covering region 41 to form an opening window having an inner diameter DC smaller than the second inner diameter D2. By forming in this way, as shown in the cross-sectional view of FIG. 6, the holding region 42 covers the upper end of the second pipe region 22 and holds the periphery of the light diffusing portion 30 between them.
(Deformation mitigation function due to thermal expansion)

The light diffusing portion 30 is not directly fixed to the pipe portion 20, but is placed and held on a step of the pipe portion 20. In other words, the light diffusing portion 30 is held by the pipe portion 20 and the cover portion 40, and each of the pipe portion 20 and the cover portion 40 is fixed to the substrate 10. That is, the pipe portion 20 and the cover portion 40 are not directly fixed to each other. With such a configuration, the stress caused by thermal expansion can be relieved.

When the pipe part constituting the light guide tube is made of an organic material such as resin, the linear expansion coefficient is different from the light diffusion part which is an inorganic material such as glass, and the amount of deformation of the resin pipe part is made of glass at high temperature. It becomes larger than the light diffusing part of. Therefore, when the light diffusing part is integrally molded with the pipe part, when the pipe part expands due to heat at the junction interface between the pipe part and the light diffusing part and presses the light diffusing part, the pipe part is damaged by the reaction. There was a possibility. On the other hand, in the light emitting device 100 according to the first embodiment, the pipe portion 20 and the light diffusing portion 30 are not integrally formed, but are intentionally held in a state where a gap (margin) is provided, so to speak, to play. By providing the above purpose, damage due to such thermal stress is avoided.
(margin)

As described above, a margin is provided between the light diffusing portion 30 and the pipe portion 20 and the cover portion 40 that hold the light diffusing portion 30. Specifically, between the light diffusion unit 30 and the second pipe region 22, that is, between the horizontal margin MH in the horizontal direction of the light diffusion unit 30, and between the light diffusion unit 30 and the holding region 42, that is, light diffusion. The thickness direction margin MV which is the vertical direction of the portion 30 is formed respectively. By providing the margin in this way, when the pipe portion 20 and the cover portion 40 having a linear expansion coefficient larger than that of the light diffusing portion 30 are expanded by the heat generation of the light emitting element, they are pressed by the contact surface with the light diffusing portion 30. It is possible to absorb the situation where the deformation occurs and cracks, distortions, etc. occur with a margin.

Further, it is preferable to form the lateral margin MH larger than the thickness margin MV. As a result, by taking a margin in the peripheral direction in which the amount of deformation increases due to thermal expansion larger than in the thickness direction, it is possible to suppress deformation in the circumferential direction and more reliably protect the light emitting device 100. ..

In this way, by separating the light diffusing plate from the plurality of light emitting elements 1 by the pipe portion 20, in addition to securing the optical path length and enhancing the light diffusing effect, the linear expansion coefficient is higher than that of the light diffusing portion 30. When the large pipe portion 20 and the outer portion expand due to the heat generated by the light emitting element 1, the situation where they are pressed by the contact surface with the light diffusing portion 30 and deformed to cause cracks, distortions, etc. is absorbed by providing a margin. It becomes possible to do.
(Cover side base area 43)

The cover-side base region 43 is a member for fixing the cover portion 40 to the substrate 10. The cover-side base region 43 extends outward from the lower end of the covering region 41. In the example of FIG. 4, etc., the cover side base region 43 is formed in a triangular shape. A covering region 41 is provided in the center of the triangular base region. That is, in a plan view, the cylindrical covering region 41 is provided in a posture in which it is substantially inscribed in the triangular cover-side base region 43. Then, at each of the triangular vertices forming the cover-side base region 43, a cover-side through hole 44 is formed as a cover-side fixing portion for fixing to the substrate 10. On the substrate 10 side, a substrate side second through hole 16 is formed as a substrate side second fixing portion at a position corresponding to the cover side through hole 44 when the cover portion 40 is arranged. A pin material PN such as a screw, a bolt, or a rivet pin is inserted into the cover side through hole 44 and the substrate side second through hole 16 to fix the cover portion 40 to the substrate 10. The second through hole 16 on the substrate side is preferably formed as an elongated hole. As a result, the cover portion 40 can be reliably fixed to the substrate 10 by absorbing some manufacturing tolerances and misalignments. In the examples of FIGS. 4 and 5, the structure for fixing the cover portion 40 to the substrate 10 is not limited to the combination of the cover side through hole 44 and the substrate side second through hole 16, and a known fixing structure can be appropriately used. Needless to say. For example, in the modified example shown in FIG. 9, a notch 44B is formed as the cover-side fixing portion in place of the cover-side through hole. Similarly, the cover-side fixing portion having this configuration can be screwed into the substrate-side second through hole 16 of the substrate 10 with a pin material such as a screw. Further, since this configuration can cope with a slight positional deviation, the second through hole 16 on the substrate side does not have to be an elongated hole.

On the substrate 10, the first fixing position on the substrate side for fixing the pipe portion 20 and the second fixing position on the substrate side for fixing the cover portion 40 are different positions in the examples of FIGS. 4 and 5. That is, the number of the first fixed position on the substrate side and the second fixed position on the substrate side are the same, and the second fixed position is alternately provided between the first fixed positions. As a result, the pipe portion 20 and the cover portion 40 can be stably and securely fixed to the substrate 10.

Further, the cover portion 40 can form a slit 46 communicating with the covering portion between the cover-side fixed portions. In the example of the cover portion 40 shown in FIG. 1, each corner of the triangular cover-side base region 43 is bent stepwise so as to be in contact with the substrate 10, and the corner portion of the cover-side base region 43 is formed. The regions other than the above are separated from the substrate 10 to form the slit 46. The slit 46 can suppress warpage due to heat. Further, through the slit 46, the pipe portion 20 covered with the cover portion 40 can partially expose the pipe side base region 24 from the cover portion 40. As a result, the cover portion 40 can be fixed to the substrate 10 without completely covering the pipe portion 20. In other words, the light diffusing portion 30 can be held by covering the pipe side pipe region 21 and the second pipe region 22 of the pipe portion 20 without making the cover portion 40 larger than necessary.

However, in the present invention, the fixed position of the pipe portion and the cover portion may be the same. For example, by providing a fixing hole in the base region on the pipe side and arranging it so as to overlap the through hole on the cover side, there is an advantage that the pipe portion and the cover portion can be fixed to the substrate at the same time with a common screw or the like.

The inner surface 47'of the holding region 42'may be formed in a vertical plane shape as shown in the enlarged cross-sectional view of FIG. 10A, but is preferably formed in a tapered shape as shown in the enlarged cross-sectional view of FIG. 10B. In the example shown in FIG. 10B, the inner surface 47 of the holding region 42 of the cover portion 40, that is, the end surface of the opening window is inclined downward in a cross-sectional view to obtain a component that reflects light due to the inclination of the end surface. It is possible to reduce it. As a result, it is effective that the light is reflected at the edge of the cover portion 40'that covers the light diffusion portion 30 and the projection pattern is projected in a double ring along the edge of the cover portion 40'. Can be avoided.

The light emitting device according to the embodiment of the present invention can be suitably used for a medical shadowless lamp or the like.

1000 ... Illumination device 100 ... Light emitting device 1 ... Light emitting element; 1a ... First light emitting element; 1b ... Second light emitting element 10 ... Board 15 ... Board side first pin hole 16 ... Board side second through hole 20 ... Pipe portion 21 ... First pipe region 22 ... Second pipe region 23 ... Recessed portion 24 ... Pipe side base region 25 ... Pipe side pin 30 ... Light diffusing portion 40, 40'... Cover portion 41 ... Covering region 42, 42'... Holding region 43 ... Cover side base area 44 ... Cover side through hole; 44B ... Notch 46 ... Slit 47, 47'... Inner surface 50 of holding area ... Reflector 110 ... Light emitting device 111 ... Light guide pipe 130 ... Diffuse glass D1 ... First inner diameter D2 ... Second inner diameter DC ... Inner diameter H2 of holding region ... Height H3 of second pipe region ... Thickness of light diffusing part HP ... Height of pipe part MV ... Thickness direction margin MH ... Lateral margin PN ... Pin material

Claims (10)

With multiple light emitting elements
A substrate having an arrangement area on the upper surface for arranging the plurality of light emitting elements in a predetermined pattern.
A cylindrical pipe portion fixed to the substrate and arranged so as to surround the arrangement region on the substrate.
A light diffusing part made of a material different from that of the pipe part and diffusing and transmitting light emitted by the plurality of light emitting elements, and a light diffusing part.
A cover portion fixed to the substrate and holding the light diffusing portion between the pipe portion and the cover portion.
Equipped with
The light diffusing portion is arranged on the upper surface of the pipe portion.
The cover portion has an inner diameter larger than the outer diameter of the pipe portion, has a covering region covering the outer surface of the pipe portion, and extends inward from the upper end of the covering region, and has an outer diameter of the light diffusing portion. It has a smaller inner diameter and comprises a holding region that covers the upper end of the light diffusing portion.
The difference in height between the arrangement position of the light diffusing portion on the upper surface of the pipe portion and the lower surface of the holding region is formed to be larger than the thickness of the light diffusing portion.
A light emitting device in which a thickness direction margin is formed between the holding region and the light diffusing portion. The light emitting device according to claim 1.
The pipe part is
A first pipe region having a first inner diameter smaller than the outer shape of the light diffusing portion and having the light diffusing portion arranged on the upper surface,
A pipe-side base region for fixing to the substrate, which is extended outward from the first pipe region, and
A light emitting device that is equipped with. The light emitting device according to claim 2.
The cover portion is a light emitting device including a cover-side base region for fixing to the substrate, which is extended outward from the covering region. The light emitting device according to claim 3.
The pipe-side base region is a light emitting device having a pipe-side fixing portion fixed to the substrate. The light emitting device according to claim 4.
The cover-side base region is a light emitting device having a cover-side fixing portion fixed to the substrate. The light emitting device according to claim 5.
The pipe-side fixing portion is a light emitting device arranged so as to overlap the cover-side fixing portion. The light emitting device according to any one of claims 2 to 6.
The first pipe region is a light emitting device formed by forming a recess portion higher than the thickness of the light emitting element on the inner wall at the lower end thereof. The light emitting device according to any one of claims 1 to 7.
A light emitting device in which the light diffusing portion is made of a glass plate. The light emitting device according to claim 8.
A light emitting device in which the pipe portion and the cover portion are made of the same material. The light emitting device according to any one of claims 1 to 9.
The plurality of light emitting elements
The first light emitting element that emits the first light emitting color,
A light emitting device including a second light emitting element having a light emitting color different from that of the first light emitting element.

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