JP2012204349A - Light-emitting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce color unevenness in a light-emitting device which emits light by mixing light in multiple colors.SOLUTION: A light-emitting device 1 comprises: a plurality of LEDs 3; a first translucent member 4 which mutually covers the LEDs 3; and a light-converting member 5 which directly covers a light-extracting surface of the first translucent member 4. The light-converting member 5 includes: regions each corresponding to the LEDs 3 and having a fluorescent material 6 which converts the wavelength of light emitted from the LEDs 3; and regions free of the fluorescent material 6. Light from the LEDs 3 and incident onto the regions having the fluorescent material 6 is emitted after being subjected to wavelength conversion by the fluorescent material 6. Light from the LEDs 3 and incident onto the regions free of the fluorescent material 6 is emitted as it is without being subjected to wavelength conversion. Thus, color unevenness of the emitted light can be reduced by appropriately setting the arrangement of the light-converting member 5.

Description

  The present invention relates to a light emitting device using a solid light emitting element such as an LED (Light emitting diode).

  2. Description of the Related Art Conventionally, a light emitting device that emits light by mixing light of a plurality of colors using an LED and a phosphor is known (for example, see Patent Document 1). For example, as shown in FIG. 8, such a light emitting device includes a plurality of LEDs 10 that emit blue light, and a phosphor layer 20 that is provided on a surface on which the blue light from the LEDs 10 is incident. The phosphor layer 20 includes a region including a green phosphor 21 that emits green light when excited by the blue light from the LED 10, a region including a red phosphor 22 that emits red light when excited by the blue light from the LED 10, and Consists of The green light and the red light emitted from these regions are mixed with the blue light from the LED 20 that has not been absorbed by the green phosphor 21 and the red phosphor 22 to become white light, and are derived from the phosphor layer 20 ( The optical path is indicated by a dashed arrow).

JP 2008-123969 A

  However, in the device as described in Patent Document 1, since the position of the green phosphor 21 and the position of the red phosphor 22 do not correspond to the position of the LED 10, the phosphors excited by the respective LEDs 10 vary. is there. Therefore, the white light derived from the position corresponding to each LED 10 may become white light with strong green light or red light for each LED 10, and color unevenness is likely to occur.

  The present invention solves the above-described problems, and an object of the present invention is to provide a light-emitting device that can reduce color unevenness of light irradiation when a plurality of solid-state light-emitting elements are used.

  The light emitting device of the present invention includes a plurality of solid light emitting elements, a first light transmissive member that covers the plurality of solid light emitting elements in common, and a light guide surface of the first light transmissive member, directly or A second light transmissive member different from the first light transmissive member, or a light conversion member that covers through an air layer, wherein the light conversion member is a part or all of the plurality of solid state light emitting devices. Corresponding to the above, a region having a phosphor for converting the wavelength of light emitted from the solid-state light emitting device is provided.

  It is preferable that the phosphor is disposed on the front surface, the back surface, or the inside of the light conversion member.

  The phosphor is preferably composed of a phosphor sheet attached to the front surface or the back surface of the light conversion member.

  The light emitting device preferably includes a first light diffusing unit that is formed between the plurality of solid state light emitting elements and diffuses light emitted from the solid state light emitting elements.

  The light emitting device preferably includes a second light diffusing unit that covers a light guide surface of the light converting member and diffuses light emitted from the plurality of solid state light emitting elements.

  The plurality of solid state light emitting devices are preferably arranged in an array or a matrix.

  The color of light derived from the light conversion member is preferably the three primary colors of light.

  According to the light emitting device of the present invention, the light emitted from each of the plurality of solid state light emitting elements is subjected to light conversion after being wavelength-converted by the light conversion member provided corresponding to the solid state light emitting elements. By setting the arrangement of the members appropriately, uneven color of the irradiated light can be reduced.

(A) is a top view of the light-emitting device which concerns on the 1st Embodiment of this invention, (b) is sectional drawing in the II line of (a), (c) is a cross section in the II-II line of (a). Figure. (A) (b) is a longitudinal cross-sectional view of the light-emitting device which concerns on the 1st modification of the said embodiment, respectively. (A) (b) is a longitudinal cross-sectional view of the light-emitting device which concerns on the 2nd modification of the said embodiment, respectively. (A) (b) (c) is a longitudinal cross-sectional view of the light-emitting device which concerns on the 3rd modification of the said embodiment, respectively. The longitudinal cross-sectional view of the light-emitting device which concerns on the 4th modification of the said embodiment. The disassembled perspective view of the light-emitting device which concerns on the 2nd Embodiment of this invention. Sectional drawing of the said light-emitting device. The longitudinal cross-sectional view of the conventional light-emitting device.

  A light emitting device according to a first embodiment of the present invention will be described with reference to FIGS. This light-emitting device uses LEDs as solid-state light-emitting elements.

  As shown in FIGS. 1A, 1B, and 1C, a light emitting device 1 includes a long wiring board 2 and a plurality of LEDs 3 arranged in an array (line shape) on the wiring board 2. , A linear light emitting device. These LEDs 3 are arranged at equal intervals, and are all blue LEDs that emit blue light. The LEDs 3 are covered in common by the first light transmissive member 4, and the light lead-out surface of the first light transmissive member 4 is covered by the light conversion member 5. The light conversion member 5 includes a region having a phosphor 6 for converting the wavelength of blue light emitted from the LED 3 and a region not having the phosphor 6 in a one-to-one correspondence with each LED 3. . The phosphor 6 includes a red phosphor 6 (R: red) that converts the wavelength of blue light from the LED 3 into red light, and a green phosphor 6 (G: green) that converts the wavelength of the blue light from the LED 3 into green light. Is composed of. The area | region which has the red fluorescent substance 6 (R) of the light conversion member 5 becomes the wavelength conversion part 7 (R), and the area | region which has the green fluorescent substance 6 (G) of the light conversion member 5 is the wavelength conversion part 7 (G). It becomes. The area | region which does not have the fluorescent substance 6 of the light conversion member 5 becomes the blue light transmissive part 7 (B: blue). The wavelength conversion units 7 (R) and 7 (G) and the blue light transmission unit 7 (B) are arranged in the order of the wavelength conversion unit 7 (R), the wavelength conversion unit 7 (G), and the blue light transmission unit 7 (B). In a repeating pattern, the light conversion member 5 is continuously arranged adjacent to each other.

  The wiring board 2 has a size of 270 mm × 30 mm, and the thickness thereof is such that deformation such as bending does not occur when the wiring board 2 is handled. The wiring board 2 is configured using a material having high thermal conductivity as a base material, and is configured using, for example, a metal such as aluminum, a resin such as glass epoxy, or an inorganic material such as ceramic as a base material. The wiring board 2 includes a flat light reflecting member (not shown) made of silver, aluminum or the like having a high light reflectance on the LED mounting surface. The term “flat” as used herein refers to a shape having irregularities with an elevation difference of about 75 μm or less. Further, the wiring board 2 includes a wiring pattern (not shown) made of a copper foil or the like that bears power supply to the LEDs 3. Note that the size, shape, and constituent materials of the wiring board 2 are not limited to those described above. Moreover, the wiring board 2 includes a holding structure (not shown) for attaching the wiring board 2 to a ceiling, a wall, or the like.

  The LED 3 has a size of about 0.3 mm square and is made of a nitride such as indium gallium nitride (InGaN). The LED 3 emits blue light having a peak wavelength at approximately 460 nm. The LED 3 may be mounted face-up on the wiring pattern of the wiring board 2 or may be flip-chip mounted. When the LED 3 is mounted face up, the LED 3 is die-bonded on the wiring pattern and wire-bonded to the wiring pattern with a gold wire or the like. When the LED 3 is flip-chip mounted, the LED 3 is bonded onto the wiring pattern via a gold bump, solder, or the like. In addition, the magnitude | size and constituent material of LED3 are not limited to said thing.

  The 1st translucent member 4 is comprised from translucent materials, such as a transparent silicone resin, a transparent epoxy resin, and transparent glass. The first translucent member 4 has an elongated bowl shape with both ends closed to form a lid, and is fixed on the wiring board 2 with a plurality of LEDs 3 included in the recess. Yes. The diameter of the semicircle forming the cross section of the first translucent member 4 is equal to or larger than the “refractive index of the first translucent member 4” times the circumscribed circle diameter of the LED 3. In addition, the shape of the 1st translucent member 4 is not limited to hook shape, For example, you may be made into semi-ellipsoid surface shape.

  The light conversion member 5 is comprised from the translucent material which has the refractive index of 1.2-1.7, for example, is comprised from transparent silicone resin. The refractive index of the translucent material constituting the light conversion member 5 is made larger than the refractive index of the translucent material constituting the first translucent member 4. The light conversion member 5 has a bowl shape that is in close contact with the light guide surface of the first light transmissive member 4 and is formed of a sheet having a thickness of 0.5 to 1 mm. The thickness of the end of the light conversion member 5 is made thinner than the thickness of the other part of the light conversion member 5.

  The light emitting device 1 includes a drive driver (not shown) that controls the light emission of the LED 3. The drive driver has a light control device composed of a switch, a microcomputer, and the like, and is connected to a commercial power source and is electrically connected to the LED 3 via a wiring pattern. The drive driver performs on / off control and dimming control of the LED 3 by controlling supply of power obtained from the commercial power source to the LED 3. A plurality of drive drivers are provided, and are composed of three types that collectively control the LEDs 3 corresponding to the wavelength conversion units 7 (R) and 7 (G) and the blue light transmission unit 7 (B), respectively. .

  The operation of the light emitting device 1 of the present embodiment configured as described above will be described. The blue light emitted from each LED 3 is one of the wavelength conversion unit 7 (R), the wavelength conversion unit 7 (G), or the blue light transmission unit 7 (B) provided corresponding to each LED 3. Is incident on. The blue light from the LED 3 incident on the wavelength conversion unit 7 (R) is converted into red light by the red phosphor 6 (R) and then led out from the light conversion member 5. The blue light from the LED 3 incident on the wavelength conversion unit 7 (G) is converted into green light by the green phosphor 6 (G) and then derived from the light conversion member 5. The blue light from the LED 3 that has entered the blue light transmitting portion 7 (B) passes through the LED 3 without being wavelength-converted, and is led out from the light conversion member 5 as blue light. Thereby, the color of the light led out from the light conversion member 5 becomes the three primary colors of light composed of red, green, and blue. These red light, green light, and blue light are easily mixed because the wavelength converting portions 7 (R), 7 (G) and the blue light transmitting portion 7 (B) are continuously arranged adjacent to each other. Together, it produces white light with little color unevenness.

  The chromaticity of the white light derived from the light conversion member 5 can be freely adjusted by performing on / off control and dimming control of a specific LED 3 using a drive driver. For example, by increasing the output of the LED 3 corresponding to the wavelength conversion unit 7 (R) and increasing the red light derived from the wavelength conversion unit 7 (R), the white light derived from the light conversion member 5 is increased. It can be white light with reddish warmth. Further, the chromaticity and brightness of the white light derived from the light conversion member 5 can be adjusted by changing the type and concentration of the phosphor 6, the concentration ratio with other phosphors, and the like.

  In addition, since the light conversion member 5 has a bowl shape, most of the light emitted from the LED 3 is incident on the light conversion member 5 at a right angle (indicated by broken arrows in FIG. 1C). See light path). Therefore, the optical path length difference of the light propagating through the wavelength conversion units 7 (R) and 7 (G) is reduced, and the blue light from the LED 3 is converted to the same wavelength regardless of the irradiation angle from the LED 3. . Thereby, the color nonuniformity of the light derived | led-out from the wavelength conversion parts 7 (R) and 7 (G) can be reduced.

  By the way, in the device as in Patent Document 1 shown in FIG. 8, the side of the LED is shielded by a frame, a reflector that reflects light, or the like, so that the side of the device cannot be irradiated with light. . On the other hand, in the light emitting device 1, the light conversion member 5 is also arranged on the side of the LED 3 because the light conversion member 5 has a bowl shape. Thereby, the light-emitting device 1 can irradiate light to the side, and controls the light distribution of the light radiated to the side by adjusting the curvature of the bowl-shaped structure of the light conversion member 5. can do.

  The blue light from the LED 3 incident on the wavelength converters 7 (R) and 7 (G) is converted in wavelength by the red phosphor 6 (R) and the green phosphor 6 (G), respectively, and these phosphor molecules And is scattered in various directions. Thereby, it becomes possible to reduce the luminance unevenness of the red light and the green light derived from the wavelength conversion units 7 (R) and 7 (G), and as a result, the wavelength conversion units 7 (R) and 7 (G). Can be made into planar light sources. On the other hand, since the phosphor is not disposed in the blue light transmitting portion 7 (B), the luminance unevenness of the blue light derived from the blue light transmitting portion 7 (B) cannot be reduced. Therefore, fine particles that scatter light may be dispersed in the blue light transmitting portion 7 (B). Thereby, it is possible to reduce the luminance unevenness of the blue light derived from the blue light transmitting portion 7 (B), and the blue light transmitting portion 7 (B) can be made into a planar light source.

  The blue light transmitting portion 7 (B) may include a blue phosphor that emits blue light that is excited by the blue light emitted from the LED 3 and has a chromaticity different from that of the blue light from the LED 3. As a result, blue light having a desired chromaticity can be obtained, and variations in blue light caused by variations in the optical characteristics of the LEDs 3 can be corrected.

  Further, the blue light emitted from the LED 3 is made by making the refractive index of the translucent material constituting the light converting member 5 larger than the refractive index of the translucent material constituting the first translucent member 4. However, total reflection at the interface between these members can be prevented. Further, a part of the light wavelength-converted by the light conversion member 5, a part of the light scattered by the light conversion member 5, and one of the light totally reflected at the interface between the light conversion member 5 and the outside (atmosphere). The part can be totally reflected at the interface and directed toward the outside of the light emitting device 1. Thus, the light extraction efficiency from the light emitting device 1 can be improved.

  The light (returned light) that is not totally reflected at the interface and returns to the inner direction of the light emitting device 1 is reflected by the light reflecting member because the LED mounting surface of the wiring board 2 is provided with the light reflecting member. Then, it can be directed again toward the outside of the light emitting device 1. Thereby, the light extraction efficiency of the light emitting device 1 can be improved.

  In addition, since the wiring board 2 is configured using a material having high thermal conductivity as a base material, heat generated by light emission of the LED 3 and heat generated by wavelength conversion by the phosphor 6 are transmitted through the wiring board 2 to the outside world. Can dissipate heat. Thereby, since the abnormal temperature rise inside the light-emitting device 1 can be prevented, the lifetime of the LED 3 can be extended, and thermal deterioration of the phosphor 6 can be suppressed.

  The end of the light conversion member 5 is located on the side of the LED 3. Since the blue light from the LED 3 is difficult to reach the end portion of the light conversion member 5, the wavelength conversion frequency by the phosphor 6 is low at the end portion of the light conversion member 5, and as a result, the fluorescence due to heat generated by the wavelength conversion Thermal degradation of the body 6 is difficult to occur. Therefore, the blue light from the LED 3 may be wavelength-converted more efficiently at the end of the light conversion member 5 than the other parts of the light conversion member 5 and may give color unevenness. Therefore, the amount of the phosphor 6 included in the end portion of the light conversion member 5 may be reduced by making the thickness of the end portion of the light conversion member 5 thinner than the thickness of other portions of the light conversion member 5. . Thereby, the improvement effect of the wavelength conversion efficiency in the edge part of the light conversion member 5 is canceled, and generation | occurrence | production of color unevenness can be reduced.

  Next, a light emitting device according to a first modification of the present embodiment is shown in FIGS. The light emitting device 1 shown in FIG. 2A has a second light transmissive member 41 different from the first light transmissive member 4 between the first light transmissive member 4 and the light converting member 5. Is provided. The second translucent member 41 is made of a translucent material similar to the first translucent member 4 and the light conversion member 5. The refractive index of the translucent material constituting the second translucent member 41 is larger than the refractive index of the translucent material constituting the first translucent member 4 and constitutes the light conversion member 5. It is made smaller than the refractive index of a translucent material. Thereby, the total reflection in the interface of the 1st translucent member 4 of the blue light radiate | emitted from LED3, and the 2nd translucent member 41 and the 2nd translucent member 41 and the light conversion member 5 are carried out. Total reflection at the interface can be prevented.

  In the light emitting device 1 shown in FIG. 1, a part of the return light is separated from the air layer inside the first light transmissive member 4 and the interface between the first light transmissive member 4 and the first light transmissive member 4. By making total reflection at two points on the interface between the light-emitting device 5 and the light-converting member 5, the light-emitting device 1 can be directed outward. On the other hand, in this modification, a part of the return light is separated from the interface between the air layer inside the first translucent member 4 and the first translucent member 4, the first translucent member 4 and Total reflection can be performed at three places, that is, the interface with the second light transmissive member 41 and the interface between the second light transmissive member 41 and the light conversion member 5. Therefore, according to this modification, the light extraction efficiency from the light emitting device 1 can be further improved as compared with the light emitting device 1 shown in FIG.

  The light emitting device 1 shown in FIG. 2B includes an air layer 8 between the first light transmissive member 4 and the light conversion member 5. Thereby, total reflection of light at the interface between the air layer 8 and the light conversion member 5 can be prevented, and much of the return light can be totally reflected at the interface between the air layer 8 and the light conversion member 5. it can. Therefore, the light extraction efficiency of the light emitting device 1 can be improved. Further, since the air layer 8 has a heat insulating action, the heat generated by the wavelength conversion by the phosphor 6 in the light conversion member 5 is prevented from being propagated to the first light transmissive member 4, thereby Thermal degradation of the one translucent member 4 can be suppressed. Moreover, the air layer 8 can also suppress the thermal degradation of the light conversion member 5 and the phosphor 6 by preventing the heat generated with the light emission of the LED 3 from being propagated to the light conversion member 5. it can.

  Next, a light emitting device according to a second modification of the present embodiment is shown in FIGS. The light emitting device 1 shown in FIG. 3A includes a phosphor layer 61 on the surface of the light conversion member 5 (light deriving surface side). The phosphor layer 61 includes a region including the red phosphor 6 (R), a region including the green phosphor 6 (G), and a region not including the phosphor 6, and each of these regions includes each LED 3. Are continuously arranged adjacent to each other at positions corresponding to. The light emitting device 1 illustrated in FIG. 3B includes a phosphor layer 61 configured in the same manner as described above on the back surface (light incident surface side) of the light conversion member 5. The phosphor layer 61 disposed on the surface of the light conversion member 5 and the phosphor layer 61 disposed on the back surface of the light conversion member 5 can be easily provided by patterning coating such as screen printing. Therefore, according to this modification, the light emitting device 1 can be more easily manufactured as compared with the light emitting device 1 shown in FIG.

  The phosphor layer 61 may be composed of a phosphor sheet attached to the surface of the light conversion member 5 or a phosphor sheet attached to the back surface of the light conversion member 5. Thereby, the light-emitting device 1 can be manufactured more simply than the light-emitting device 1 shown in FIG.

  Next, a light emitting device according to a third modification of the present embodiment is shown in FIGS. The light emitting device 1 shown in FIG. 4A includes a first light diffusion portion 9a on a wiring board 2 in a region sandwiched between adjacent LEDs 3. The light emitting device 1 shown in FIG. 4B includes a first light diffusing portion 9a on the light guide surface of the first light transmissive member 4 located in a region sandwiched between adjacent LEDs 3. The light emitting device 1 shown in FIG. 4C includes a first light diffusion portion 9a on the light incident surface of the light conversion member 5 located in a region sandwiched between adjacent LEDs 3. These first light diffusing portions 9 a are formed in a concavo-convex shape, and diffuse blue light and return light emitted from the LED 3 to the side of the LED 3 so as to be directed toward the outside of the light emitting device 1. As a result, it is possible to increase the amount of light in the region sandwiched between the LEDs 3 where the amount of light tends to be small, so that it is possible to reduce uneven brightness and uneven color of the light emitting device 1. In addition, the 1st light-diffusion part 9a does not necessarily need to be comprised from uneven shape, for example, may be comprised from light-diffusion particle | grains.

  Next, a light emitting device according to a fourth modification of the present embodiment is shown in FIG. The light emitting device 1 shown in FIG. 5 includes a second light diffusing portion 9 b that covers the light guide surface of the light conversion member 5. The second light diffusing unit 9b is made of, for example, a light transmissive material in which particulate matter is dispersed. In this case, for example, silicon dioxide or ceramic is used as the particulate material, and for example, transparent glass or transparent acrylic resin is used as the translucent material. Or the 2nd light-diffusion part 9b is comprised from the said translucent material by which the unevenness | corrugation was formed in at least one of the surface or the back surface by frost processing etc. The second light diffusion portion 9b preferably has a linear transmittance of 50% or less. The second light diffusing unit 9b diffuses the white light derived from the light conversion member 5 in various directions. Thereby, compared with the light-emitting device 1 shown in FIG. 1, the color unevenness and luminance unevenness of the white light derived from the light-emitting device 1 can be further reduced. When the second light diffusing portion 9b is made of transparent glass or transparent acrylic resin having a relatively high hardness, the second light diffusing portion 9b is used as an outer shell member that protects the light emitting device 1 from an impact or the like. Can also work. In addition, in this modification, the second light diffusion portion 9b is disposed with a gap between it and the light derivation surface of the light conversion member 5, but is disposed in close contact with the light derivation surface of the light conversion member 5. May be.

  According to the above-described embodiment and its modification, the linear light-emitting device 1 that can emit white light with reduced color unevenness and brightness unevenness and can adjust the chromaticity of the white light is obtained. be able to. Further, the light emitting device 1 can emit white light that can be subjected to light distribution control on the side of the device.

  Next, a light emitting device according to a second embodiment of the present invention will be described with reference to FIGS. The light emitting device 11 is a planar light emitting device including a rectangular wiring board 2 and a plurality of LEDs 3 arranged in a matrix (planar shape) on the wiring board 2. These LEDs 3 are arranged in a matrix of 5 × 6 horizontally at equal intervals, and are all blue LEDs that emit blue light. The LEDs 3 are commonly covered with a rectangular first light transmissive member 4, and a light conversion member 5 is fixed to the light guide surface of the first light transmissive member 4. The light conversion member 5 is approximately the same size as the light guide surface of the first light transmissive member 4, and has a rectangular frame body in which both the light incident surface and the light guide surface are open, and the inside of the frame member 5 in the vertical direction. It is comprised from the strip | belt-shaped board partitioned off in a grid | lattice form of piece x 6 pieces. This belt-like plate is provided with a flat light reflecting member (not shown) made of silver, aluminum or the like having a high light reflectance on the surface thereof. Each grating has an inverted quadrangular pyramid shape with 100% opening on the light exit surface side (see FIG. 7), and is arranged at a position corresponding to each LED 3. Each grating includes a wavelength conversion unit 7 (R) made of a translucent material in which red phosphor 6 (R) is dispersed, or a translucent material in which green phosphor 6 (G) is dispersed. The wavelength conversion unit 7 (G) configured or the blue light transmission unit 7 (B) configured only from the translucent material is filled. The translucent material is made of, for example, a silicone resin. Ten wavelength conversion units 7 (R) and 7 (G) and 10 blue light transmission units 7 (B) are arranged in each of the light conversion members 5. In addition, the number and arrangement of the LEDs 3 are not limited to those illustrated. Further, the structure of the light conversion member 5 is not limited to that of the present embodiment, and for example, the shape of the grating may be an inverted hexagonal frustum shape in which the light exit surface side is 100% open. Furthermore, the arrangement of the wavelength conversion units 7 (R) and 7 (G) and the blue light transmission unit 7 (B) is not limited to that of the present embodiment.

  The light emitting device 11 is different except that the arrangement of the LEDs 3 on the wiring board 2, the structure of the light converting member 5, and the forms of the wavelength converting portions 7 (R), 7 (G) and the blue light transmitting portion 7 (B) are different. It has the same configuration as the light emitting device 1 shown in FIG.

  The operation of the light emitting device 11 of the present embodiment configured as described above will be described. The blue light emitted from each LED 3 is either one of the wavelength conversion unit 7 (R), the wavelength conversion unit 7 (G), or the blue light transmission unit 7 (B) arranged corresponding to each LED 3. Is emitted from the light emitting device 11 as red light, green light, or blue light. Here, since the wavelength conversion units 7 (R) and 7 (G) and the blue light transmission unit 7 (B) are uniformly distributed adjacent to each other in the light conversion member 5, these red light, green Light and blue light are easily mixed and become white light with little color unevenness.

  Since each grating | lattice of the light conversion member 5 is made into a reverse quadrangular pyramid shape, and the light reflection member is provided in the slope, the wavelength conversion parts 7 (R) and 7 (G) and the blue light transmission part 7 (B ) Can be directed to the outside of the light emitting device 11 (see the broken line arrow in FIG. 7). Thereby, the light extraction efficiency of the light emitting device 11 can be improved.

  According to the above-described embodiment, it is possible to obtain the planar light emitting device 11 that can emit white light with reduced color unevenness and brightness unevenness and can adjust the chromaticity of the white light.

  The light emitting device according to the present invention is not limited to the above embodiment, and various modifications can be made. For example, in this embodiment, the light conversion member is configured to include a phosphor corresponding to a part of the plurality of solid state light emitting elements, but includes a phosphor corresponding to all the solid state light emitting elements. The configuration may be different. Further, in the present embodiment, the solid light-emitting element is an LED that emits blue light, but is not limited thereto, and is an LED that emits green light, blue-green light, blue-violet light, violet light, or ultraviolet light. Alternatively, a solid light emitting element other than an LED such as an organic EL element may be used. When the solid-state light emitting device is composed of LEDs emitting blue-violet light, violet light, or ultraviolet light, it is difficult to directly use these low-viscosity light for white light generation. A phosphor is provided corresponding to the above, and light converted in wavelength by the phosphor is used for white light generation. Further, the solid light-emitting element does not necessarily need to be composed of one type of solid light-emitting element, and may be composed of a plurality of types of solid-state light-emitting elements. In the present embodiment, one type of phosphor is disposed for one solid-state light emitting element, but a plurality of types of phosphors may be disposed for one solid-state light emitting element. One phosphor may be arranged for each solid-state light emitting device. The light emitting device may be configured to emit light other than white light. Further, in the present embodiment, the first translucent member covers all the solid light emitting elements in common, but each solid light emitting element may be individually coated, or a specific solid A plurality of light emitting elements may be covered one by one.

1, 11 Light emitting device 3 Solid light emitting element (LED)
4 First translucent member 41 Second translucent member 5 Light converting member 6 Phosphor 6 (R) Red phosphor 6 (G) Green phosphor 8 Air layer 9 a First light diffusion portion 9 b Second Light diffusion part

Claims (7)

A plurality of solid state light emitting devices;
A first translucent member that covers the plurality of solid state light emitting elements in common;
A light conversion member that covers the light guiding surface of the first light transmissive member directly or via a second light transmissive member or an air layer different from the first light transmissive member,
The light conversion member includes a region having a phosphor corresponding to a part or all of the plurality of solid state light emitting elements and converting a wavelength of light emitted from the solid state light emitting elements. apparatus.   The light emitting device according to claim 1, wherein the phosphor is disposed on a front surface, a back surface, or an inside of the light conversion member.   The light emitting device according to claim 2, wherein the phosphor is made of a phosphor sheet attached to a front surface or a back surface of the light conversion member.   The first light diffusing section that is formed between the plurality of solid state light emitting elements and diffuses the light emitted from the solid state light emitting elements is provided. The light emitting device described.   5. The device according to claim 1, further comprising: a second light diffusing portion that covers a light guide surface of the light conversion member and diffuses light emitted from the plurality of solid state light emitting elements. The light emitting device according to item.   The light emitting device according to claim 1, wherein the plurality of solid state light emitting elements are arranged in an array or a matrix.   The light emitting device according to any one of claims 1 to 6, wherein the color of light derived from the light conversion member is three primary colors of light.

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