JP2008041567A - Light emission device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a light emission device which can produce a light emitting surface in which a luminance unevenness and a color unevenness are controlled. <P>SOLUTION: The light emission device includes a substrate 10, a semiconductor light emitting element 12 provided on the substrate 10, a first reflecting surface 20a provided in a position to face a first side surface 13a of the semiconductor light emitting element 12 and a second reflecting surface 22a which is provided in a position to face a second side surface 13b of the semiconductor light emitting element 12 and is projected toward the second side surface 13b. The first reflecting surface 20a has an inclined surface which has a larger distance with the semiconductor light emitting element 12 toward an upper direction of the substrate 10, and the second reflecting surface 22a has a surface which has a minimum distance to a center of the semiconductor light emitting element and has a larger distance as parting farther from the center, and an emitted light from the second side surface 13b can be reflected to the first reflecting surface. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a light-emitting device using an LED as a light source, which is used in, for example, a backlight for an LCD, a light source for a scanner, or a lighting device replacing a fluorescent lamp. The present invention relates to a light emitting device.

As a backlight light source in a display device such as an LCD, a light emitting element such as a semiconductor laser or a light emitting diode (hereinafter referred to as LED) may be used. When the LED is used as a backlight light source, it is necessary to convert the emitted light from the LED chip, which is point emission, into surface emission. Here, a display device 100 according to a conventional example will be described with reference to FIGS. 8 and 9. In the display device 100, a light guide plate 102 is provided in the effective light emitting region 104, and a plurality of LED devices (a case where three LED devices are provided in FIGS. 8 and 9 are illustrated) 106 on the incident end face of the light guide plate 102. Is provided. The bottom surface of the light guide plate 102 is provided with a reflection pattern (not shown) for diffusing light upward, or has a structure (not shown) for diffusing light on the incident end surface, or the light emitting surface of the light guide plate A configuration in which a diffusion sheet (not shown) or the like is disposed on the (upper surface) is used.
JP 2006-114854 A (published April 27, 2006) JP 2005-310680 A (published November 4, 2005) Japanese Utility Model Publication No. 5-50752 (released July 2, 1993) JP 2005-276629 A (released on October 6, 2005) JP 2004-39595 A (published February 9, 2004) JP 10-276298 A (published October 13, 1998)

  However, the above configuration causes a problem that the entire light emitting surface cannot emit light uniformly. Specifically, even if the light emission is performed in the vicinity of the center of the light emitting surface, unevenness in brightness occurs between the region near the LED device and between the LED devices. That is, an “eyeball phenomenon” in which the LED portion appears brighter than other regions may occur.

  In particular, when a full-color light source that emits red, green, and blue light from an LED chip is used, the light emission position varies depending on the color. For this reason, the occurrence of the eyeball phenomenon contributes to color unevenness in the surface. Furthermore, even when a light source that excites one or a plurality of phosphors having different emission colors is used with a single-color LED chip that has been frequently used in recent years, the problem of uneven brightness is still not solved.

  For this reason, it is an important issue to eliminate the uneven luminance and the uneven color in the LED light source that is linear or on the surface. In particular, when used in an LCD backlight, it is possible to practically suppress luminance unevenness and color unevenness near the center by sacrificing peripheral luminance unevenness and color unevenness. However, in this case, as shown in FIG. 9, the invalid area 108 increases and the effective light emitting area 104 decreases. This is an obstacle to miniaturization of the LCD backlight. Note that luminance unevenness and color unevenness (unevenness: not uniform in the surface) are usually evaluated by increasing the luminance at nine locations on the light emitting surface shown in FIG.

  In order to suppress the eyeball phenomenon, it is preferable to use a linear light source as an illumination device. In this case, the light can be uniformly incident on the light guide plate. However, although LED chips vary in size depending on the type, they are generally cubes with a side of about 300 μm. Good linear light emission can be achieved by simply arranging these LED chips on a straight line at regular intervals. Hard to get. Thus, for example, Patent Document 1 discloses a technique in which individual LED chips are surrounded by a reflecting wall to increase the luminance between the LED chips and suppress the eyeball phenomenon. However, if the individual LED chips are individually enclosed, the space between the LED chips becomes dark, and the effect of the reflection wall is only to extract light upward, especially when applied to a linear light source. The effect of reducing the phenomenon may not be obtained.

  Patent Document 2 discloses an LED device that takes into account the light on the end face of an LED chip provided in a recess, where one reflecting wall reflects light upward and the other reflecting wall reflects light. A structure reflecting in the direction of one reflecting wall is disclosed. However, there is no description about reflection in a state where a desired light quantity is secured. Therefore, it may not be possible to sufficiently eliminate the eyeball phenomenon.

  Patent Document 3 discloses a structure in which a reflecting wall is provided between two-dimensionally arranged LED chips on a single plane. However, in Patent Document 3, the main purpose is only to reflect light emitted from the LED chip upward, and no consideration is given to uneven light emission.

  Moreover, although patent document 4-6 discloses the technique of a linear or planar light source, it does not describe anything about suppressing the eyeball phenomenon as in patent documents 1-3.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a light emitting device in which luminance unevenness and color unevenness are reduced and generation of an eyeball phenomenon is suppressed.

  A first light emitting device according to the present invention includes a substrate, a semiconductor light emitting element provided on the substrate, a first reflecting surface provided at a position facing a first side surface of the semiconductor light emitting element, and the semiconductor light emitting element. A second reflection surface provided at a position facing the second side surface and projecting toward the second side surface, wherein the first reflection surface follows the direction from the substrate toward the light emission surface. And the second reflecting surface is a surface that minimizes the distance from the center of the semiconductor light emitting element and increases the distance from the semiconductor light emitting element as the distance from the center increases. The light emitted from the second side surface can be reflected to the first reflecting surface.

  According to the above configuration, the second reflecting surface can reflect the light emitted from the second side surface so that the light is directly incident on the first reflecting surface. For this reason, it is possible to cause light emitted from the second side surface to wrap around the first reflecting surface while minimizing the decrease in the amount of light. And since the light which injects into a 1st reflective surface will be reflected in the light emission surface direction, desired brightness | luminance can be ensured also in the light emission surface of the area | region away from the center of a semiconductor light-emitting device. As a result, the difference in luminance between the center and the periphery of the semiconductor light-emitting element can be reduced, and a light-emitting device that suppresses the eyeball phenomenon and realizes uniform light emission can be provided. In particular, when the light emitting surface realized by one semiconductor light emitting element is a rectangle, the distance from the semiconductor light emitting element is long in the end region in the longitudinal direction, which tends to cause a problem of low luminance. However, according to the above configuration, the second reflecting surface is arranged on the short side, so that light can be circulated to a region where light emission is difficult to reach, and a light emitting device capable of realizing a light emitting surface in which uneven luminance is suppressed. Can be provided.

  In the first light emitting device according to the present invention, it is preferable that a plurality of the semiconductor light emitting elements are linearly arranged on the substrate. According to this configuration, it is possible to provide a light emitting device that can be used as a linear light source in which uniform light emission is realized in a linear light emitting region.

  A second light emitting device according to the present invention includes a substrate and a semiconductor light emitting element group in which at least two or more semiconductor light emitting elements provided on the substrate are linearly arranged, The semiconductor light emitting element group is provided so that the arrangement direction thereof is parallel, and the first reflecting surface provided at a position facing the first side face of the semiconductor light emitting element and the position facing the second side face of the semiconductor light emitting element. And a second reflecting surface that protrudes toward the second side surface, wherein the first reflecting surface is an inclined surface that increases in distance from the semiconductor light emitting element in the upward direction of the substrate, The two-reflection surface is a surface that minimizes the distance from the center of the semiconductor light-emitting element and increases with the distance from the semiconductor light-emitting element, and emits light from the second side surface to the first reflection surface. With reflection on the surface That.

  According to the above configuration, the semiconductor light emitting element group in which a plurality of semiconductor light emitting elements surrounded by the first reflecting surface and the second reflecting surface are arranged is included. The second reflecting surface can reflect light emitted from the second side surface so that the light is directly incident on the first reflecting surface. That is, the light emission from the second side surface can be caused to wrap around the first reflecting surface in a state where the decrease in the light amount is minimized. And since the light which injects into a 1st reflective surface will be reflected in the light emission surface direction, desired brightness | luminance can be ensured also in the light emission surface of the area | region away from the center of a semiconductor light-emitting device. As a result, even in a planar light-emitting device that has a large area using a plurality of semiconductor light-emitting elements, a light-emitting device that suppresses the eyeball phenomenon and realizes uniform light emission can be provided.

  In the second light emitting device according to the present invention, it is preferable that the semiconductor light emitting elements constituting each other are not arranged adjacent to each other between the adjacent semiconductor light emitting element groups when viewed in plan.

  According to this configuration, the semiconductor light emitting elements can be evenly arranged in the light emitting region. Therefore, it is possible to provide a light-emitting device in which further improvement in luminance unevenness is realized.

  In the first and second light emitting devices according to the present invention, the second reflecting surface is preferably a surface capable of reflecting light emitted from the second side surface in a direction parallel to the second side surface. According to this configuration, light emitted from the second side surface can be reliably incident on the first reflecting surface. Therefore, it is possible to contribute to improvement in luminance unevenness.

  In the first and second light emitting devices according to the present invention, the maximum height of the first reflecting surface along the direction from the substrate toward the light emitting surface is higher than the upper surface of the semiconductor light emitting element intersecting the direction. Therefore, it is preferable that it is high. According to this configuration, light emitted from the first side surface and light that has entered from the second side surface can be reliably reflected on the light emitting surface.

  In the first and second light emitting devices according to the present invention, the height of the second reflecting surface is preferably higher than the upper surface of the semiconductor light emitting element and lower than the first reflecting surface. According to this configuration, when light emitted from the second side surface is circulated to the first reflecting surface side, all of the light can be reliably reflected to the light emitting surface side by the first reflecting surface.

  In the first and second light emitting devices according to the present invention, it is preferable that a continuous peripheral wall surrounding the semiconductor light emitting element, the first reflecting surface, and the second reflecting surface is provided. According to this configuration, it is possible to satisfactorily form a translucent resin that covers the semiconductor light emitting element. Here, needless to say, the translucent resin may be a resin containing a phosphor.

  In the first and second light emitting devices according to the present invention, it is preferable that the semiconductor light emitting element is covered with a translucent resin.

  In the first and second light-emitting devices according to the present invention, a light-transmitting first resin that embeds between the semiconductor light-emitting elements and light emitted from the semiconductor light-emitting elements are separated on the first resin. It is preferable that the second resin containing a phosphor that converts the light into the light having the above wavelength is lower than the upper surface of the peripheral wall. According to this configuration, since the phosphor plays the role of a scattering material, the color unevenness can be further improved.

  In the first and second light emitting devices according to the present invention, the substrate is provided with a conductive pattern electrically connected to the semiconductor light emitting element, and the semiconductor light emitting element is a blue light emitting element or an ultraviolet light emitting element. It is any element, and the conductive pattern preferably has a silver surface. According to this configuration, even if silver is visible light, the reflectance is high even for light up to a short wavelength. Therefore, loss of light can be prevented.

  In the first and second light emitting devices according to the present invention, it is preferable that at least one of the first reflecting surface and the second reflecting surface is silver. According to this configuration, it is possible to reduce the loss of light amount and further improve the luminance unevenness.

  Embodiments of the present invention will be described below with reference to the drawings.

(First embodiment)
A first embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a plan view schematically showing the light emitting device according to the first embodiment. FIG. 2 is a schematic diagram illustrating an example of internal connection of a plurality of light emitting elements. FIG. 3 is a plan view showing a part of FIG. 1 in an enlarged manner, and a part thereof is omitted. 4A is a cross-sectional view taken along line XX in FIG. FIG. 4B is a cross-sectional view taken along line YY in FIG.

  As shown in FIG. 1, the light emitting device according to the first embodiment includes a substrate 10 and a plurality of semiconductor light emitting elements arranged in a line on the substrate 10. In the present embodiment, a case where an LED chip 12 is applied as an example of a semiconductor light emitting element will be described. The LED chip 12 is surrounded by the peripheral wall 11. As the LED chip 12, various LED chips such as GaAlAs red LED, GaP green LED, InGaAlP green to red LED, GaN ultraviolet LED, blue LED, and green LED can be used.

  In the light emitting device according to this embodiment, as shown in FIG. 3, a conductive pattern 16 is provided on the bottom surface of the substrate 10 surrounded by the peripheral wall 11. The conductive pattern 16 is electrically connected to the LED chip 12 via the metal wire 14. Details of the peripheral wall 11 will be described later. The surface of the conductive pattern 16 is preferably coated with silver. Silver has a feature that it has a high reflectivity even for visible light even for light up to a short wavelength. Therefore, when the LED chip 12 emitting blue light or ultraviolet light is used, it exhibits a good reflectivity. And has the advantage that light loss can be prevented. Moreover, in order to pass more electric current and ensure brightness, it is preferable that the conductive pattern 16 is large. By forming silver on the conductive pattern 16 having a large pattern, the reflectance of light emitted from the LED chip 12 can be further increased. The substrate 10 is provided with electrode terminals 18. It is electrically connected to other wiring (not shown) via the electrode terminal 18.

  Here, an internal connection state between the plurality of LED chips 12 will be described. As shown in FIG. 2, the LED chips provided on a straight line are divided into a first block 60a and a second block 60b that are wired in series in a number that is easy to drive, and the first block 60a and the second block 60b are arranged in parallel. It is preferable to connect. The first block 60a and the second block 60b are generally driven by a sink type low current power source. For this reason, if all LED chips have the same emission color, the brightness does not change even if the number of LED chips in each block is different, but the same number is preferable in order to equalize the load applied to the power supply. When different types of LED chips are mixed and arranged, the same emission color can be obtained for each block by making the number of each type of LED chip the same. For example, seven GaN blue LEDs are arranged in the first block 60a, and seven GaN blue LEDs are arranged in the second block 60b. In another example, four GaN blue LEDs and three InGaAlP red LEDs are arranged in the first block 60a, and four GaN blue LEDs and three InGaAlP red LEDs are arranged in the second block 60b. By setting it as such a wiring form, an LED chip can be light-emitted with a practical voltage.

  Next, the peripheral structure of the LED chip 12 will be described in detail. As shown in FIG. 3, the 1st reflective surface 20a is provided in the position facing the 1st side surface 13a which cross | intersects the sequence direction of LED chip 12. As shown in FIG. The first reflecting surface 20a is a member for reflecting light emitted from the direction of the first side surface 13a toward the light emitting surface 28. Therefore, it has an inclination such that the distance from the LED chip 12 increases in the direction from the substrate 10 toward the light emitting surface 28. Specifically, a convex reflection part 20 having two first reflection surfaces 20 a can be provided between the two LED chips 12. As shown in FIG. 4A, the reflection portion 20 has a shape that tapers in the upward direction of the substrate 10. The first reflecting surface 20a is preferably capable of reflecting reflected light at an angle of 45 ° to 90 ° with respect to the light emitting surface 28. The inclination of the first reflecting surface 20a is preferably an inclination that can most suppress the eyeball phenomenon depending on the distance between the LED chips 12 and the LED chips 12, the height from the substrate 10 to the light emitting surface 28, and the like.

  The reflection unit 20 can be formed of a ceramic material such as alumina, a known resin, or the like. The surface of the reflection part 20 is preferably covered with a silver film. This is because the silver film has a high reflectivity, and thus the light incident on the first reflecting surface 20a can be favorably reflected in the direction of the light emitting surface 28.

  On the other hand, the second reflective surface 22a is provided at a position facing the second side surface 13b of the LED chip 12. The second side surface 13 b is a side surface along the arrangement direction among the side surfaces of the LED chip 12. The second reflection surface 22a is a surface for allowing the light reflected by the second side surface 13b to directly enter the first reflection surface 20a. That is, the second reflecting surface 22a plays a role of causing light emitted from the second side surface 13b to wrap around the first reflecting surface 20a while suppressing a decrease in the amount of light.

  The distance between the second reflecting surface 22a and the LED chip 12 is such that the center of the LED chip 12 is minimized and the distance increases toward the outer side of the LED chip 12. That is, as shown in FIGS. 3 and 4B, the second reflecting surface 22a protrudes toward the second side surface 13b. More specifically, the second reflecting surface 22 a protrudes toward the center of the LED chip 12. As a member constituting such a second reflecting surface 22a, in this embodiment, a case where a triangular prism-like reflecting portion 22 is provided is illustrated. In addition, although the case where it was a plane was shown as the 2nd reflective surface 22a, it is not limited to this. For example, it may be a curved surface. The reflection part 22 can be comprised with the member similar to the reflection part 20, and it is preferable that the surface used as the 2nd reflection surface 22a is similarly covered with the silver film.

  The maximum height of the first reflecting surface 20a (the position of the uppermost end of the reflecting portion 20 with respect to the substrate 10) is preferably higher than the upper surface of the LED chip 12. Further, the maximum height of the second reflecting surface 22a (the position of the uppermost end of the reflecting portion 22 with respect to the substrate 10) is higher than the upper surface of the LED chip 12, and the maximum height of the first reflecting surface 20a is It is preferable that it is low. According to this configuration, the second reflecting surface 22a is at a lower position than the first reflecting surface 20a. Therefore, the light reflected by the second reflecting surface 22 a and entering the first reflecting surface 20 a can be reflected by the light emitting surface 28. As a result, a desired luminance can be ensured even at a position away from the center of the light emitting surface 28.

  Next, the peripheral wall 11 will be described. As shown in FIG. 1, the peripheral wall 11 surrounds the LED chip 12. As shown in FIG. 1, when a plurality of LED chips 12 are provided, it is preferable to surround the whole of the plurality of LED chips 12 with one continuous peripheral wall 11. The height of the peripheral wall 11 is preferably higher than at least the reflecting portion 20 and the reflecting portion 22. For the peripheral wall 11, a ceramic member such as alumina or a known resin can be used. When using a resin, it is preferable to use a white resin so as to obtain a reflection effect. As the white resin, for example, a polyamide-based resin such as polyphthalamide containing titanium oxide can be used. Moreover, the surrounding wall 11 and the reflection parts 20 and 22 can be shape | molded simultaneously. In the case of simultaneous molding, it is preferable to perform molding using a mold using a resin from the viewpoint of simplicity of the manufacturing process. The peripheral wall 11 preferably has a shape in which the entire opening diameter increases toward the light emitting surface 28 (in accordance with the upward direction of the substrate 10). In this case, since the peripheral wall 11 becomes an inclined surface, it can contribute to efficiently reflecting the light emitted from the LED chip 12 toward the light emitting surface 28 side.

  Next, the translucent resin 24 provided in the peripheral wall 11 will be described. The LED chip 12 is covered with a translucent resin 24. As the translucent resin 24, various known resins such as an epoxy resin and a silicone resin can be used. The translucent resin 24 may contain a phosphor. Moreover, although the translucent resin 24 can also consist of a kind of layer, two different kinds of layers may be laminated | stacked.

  In the present embodiment, a case where a translucent resin 24 in which two different types of layers are laminated is provided will be described as an example. As shown in FIGS. 4A and 4B, a first resin 24 a is provided between the LED chips 12. As the 1st resin 24a, it is resin which has translucency which does not contain fluorescent substance, for example, can use an epoxy resin and silicone system resin. The height of the first resin 24a is preferably the same as or lower than the uppermost end of the second reflecting surface 22a (the upper surface of the reflecting portion 22). In this configuration, the first resin 24a is formed by pouring a molten resin material after the LED chip 12 is mounted, but the shape is once stabilized at the upper end of the reflecting portion 22 due to surface tension. Thus, there is an advantage that the first resin 24a can be formed. A second resin layer 24b is provided on the first resin 24a. As the second resin 24b, a resin mixed with a phosphor that is excited by the emitted light of the LED chip 12 and emits another light is used. The second resin 24b is preferably the same or lower than the uppermost end of the peripheral wall 11. The advantage of providing the translucent resin 24 in which the first resin 24a and the second resin 24b are laminated will be described later.

  As shown in FIG. 4A, the metal wire 14 that electrically connects the LED chip 12 and the conductive pattern 16 of the substrate 10 may be exposed from the first resin 24a. In addition, as the phosphor (fluorescent dye, fluorescent pigment) mixed in the second resin layer 24b, any of various organic and inorganic phosphors may be used.

  Next, the function and effect of the light emitting device according to this embodiment will be described with reference to FIG. In the present embodiment, first, by providing the second reflecting surface 22a, the light emission L1 from the second side surface 13b can be reflected in the direction along the arrangement direction (light L2). That is, the light from the second side surface 13b can be circulated to the first side surface 13a side. Thereafter, the light L2 is reflected to the light emitting surface 28 side by the first reflecting surface 20a. Thereby, in the light-emitting device concerning this embodiment, the brightness nonuniformity of the center part of LED chip 12 and its peripheral region can be reduced, and the light-emitting device by which the eyeball phenomenon was suppressed can be provided.

  In addition, according to the present embodiment, the translucent resin 24 has a laminated structure of the first resin 24a that does not contain a phosphor and the second resin 24b that contains a phosphor. The optical path length when the emitted light passes through the second resin layer 26 can be made constant. This function and effect will be described with reference to FIG. That is, the light L3 that directly passes through the second resin layer 26, the light L4 that enters the second resin 24b after being reflected by the first reflecting surface 20a, and is reflected by the first reflecting surface 20a and the second reflecting surface 22a. The light path length that passes through the second resin 24b is substantially the same for the light L5 that subsequently enters the second resin 24b. Therefore, the amount of light to be converted is constant in any optical path. The color of the light emitted from the LED chip 12 is almost the same as long as the length of the light passing through the second resin layer 26 is the same because the light directly passing through the resin and the light converted by the phosphor appear to be mixed. Looks color. As a result, color unevenness in the light emitting surface can be suppressed.

  With the above-described effects, a light emitting device including the LED chips 12 arranged in a line shape with reduced luminance unevenness and color unevenness can be realized.

  An example of a combination of the type of LED chip 12 and a phosphor that can be applied to the light emitting device according to the present embodiment is shown below. When a GaN-based LED chip having an emission peak wavelength of 460 nm is used as the LED chip, and YAG (yttrium aluminum garnet) activated with trivalent Ce is used as the phosphor, the blue light emitted from the LED chip 12 and the phosphor are emitted from the phosphor. Yellow light is mixed to obtain white light emission.

However, the above combination only appears to be white for the eyes, and is an effective combination for illumination, but not all display colors can be reproduced well with a liquid crystal backlight. This is because a color filter emits a color in a full-color liquid crystal display device, and it is more advantageous to use a phosphor that emits light at the transmittance peak of each color filter. As such a combination, for example, a GaN-based LED chip having an emission peak wavelength of 440 nm is used as the LED chip, and (BaSr) ₂ SiO ₄ fluorescence activated with divalent Eu (europium) as a phosphor emitting green light. When a CaAlSiN ₃ phosphor activated with divalent Eu is used as a phosphor that emits red light, a wide NTSC ratio and high color rendering properties can be obtained.

  In addition, as the shape of the LED chip 12, it is preferable to use a rectangular LED chip as compared with an LED chip having a square shape in plan view. In this case, it is possible to obtain a linear light source having a narrow width without lowering the light emission efficiency of the LED chip by arranging the LED chip in the longitudinal direction.

(Second Embodiment)
A light emitting device according to a second embodiment will be described with reference to FIG. In the following description, differences from the first embodiment will be described. Therefore, for convenience of explanation, members having the same functions as those explained in the first embodiment are given the same numbers, and explanation thereof is omitted.

  As shown in FIG. 7, the light emitting device according to the second embodiment includes a plurality of semiconductor light emitting element groups 30 in which a plurality of LED chips 12 are linearly arranged in a region surrounded by the peripheral wall 11. The semiconductor light emitting element group 30 has the same structure as that of the linear light emitting device described in the first embodiment. The semiconductor light emitting element group 30 is arranged so that its arrangement direction is parallel. Moreover, in the adjacent semiconductor light emitting element group 30, LED chip 12 which comprises each is arrange | positioned so that it may not adjoin. That is, when the entire light emitting surface 28 is viewed in plan, the LED chips 12 are arranged in a lattice pattern. According to this configuration, it is possible to further suppress uneven luminance in the light emitting surface 28.

  According to the light emitting device according to the second embodiment, even in a planar light emitting device whose area is increased by using a plurality of LED chips 12 (semiconductor light emitting elements), unevenness in luminance is suppressed and uniform. A light-emitting device that realizes light emission can be provided. The light emitting device according to the second embodiment can be used as a light source device directly under the light guide plate or without using the light guide plate.

  In the above description, the case where the first reflecting surface 20a and the second reflecting surface 22a face each other has been described. However, the present invention is not limited to this. For example, a curved surface may be used as long as the positional relationship with respect to the first side surface and the second side of the LED chip 12 is maintained. Furthermore, although this embodiment demonstrated the case where the LED chip 12 was arranged in linear form, it is not limited to this. For example, the LED chip 12 may be individually surrounded by a peripheral wall. In this case, if the light emitting device is to realize a rectangular light emitting surface, it is preferable to provide the first reflecting surface 20a on the long side and the second reflecting surface 22a on the short side. By adopting such a configuration, it is possible to provide a light-emitting device that can circulate light to the end region in the longitudinal direction where the light of the LED chip 12 is most difficult to reach, and can realize a light-emitting surface with uniform luminance.

  The present invention is not limited to the above-described embodiments, and various modifications can be made within the scope of the claims, and the technical means disclosed in different embodiments can be appropriately combined. Embodiments are also included in the technical scope of the present invention.

  The light emitting device of the present invention can improve unevenness in brightness and color by providing a reflecting surface at an optimal angle, and can be suitably used in the field of image display that requires a backlight device such as an LCD.

It is a top view showing typically the light emitting device concerning a 1st embodiment of the present invention. It is a figure explaining the internal connection of the light-emitting device concerning 1st Embodiment. It is a figure which shows the light-emitting device which concerns on 1st Embodiment, and expands and shows the A section of FIG. It is sectional drawing which shows the light-emitting device which concerns on 1st Embodiment, and shows the cross section along the XX line of FIG. It is a top view for demonstrating the effect of the light-emitting device which concerns on 1st Embodiment. It is sectional drawing for demonstrating the effect of the light-emitting device which concerns on 1st Embodiment. It is a top view which shows the light-emitting device which concerns on 2nd Embodiment. It is a perspective view which shows the light-emitting device which concerns on a prior art. It is a top view which shows the light-emitting device which concerns on a prior art. It is a top view which shows the light-emitting device which concerns on a prior art.

Explanation of symbols

10 substrate 11 peripheral wall 12 LED chip (semiconductor light emitting device)
14 Metal wire 16 Conductive pattern 18 Electrode terminal 20 Reflecting portion 20a First reflecting surface 22 Reflecting portion 22a Second reflecting surface
24 translucent resin 24a first resin 24b second resin 28 light emitting surface 30 LED chip group

Claims (12)

A substrate,
A semiconductor light emitting device provided on the substrate;
A first reflecting surface provided at a position facing the first side surface of the semiconductor light emitting element;
A second reflecting surface provided at a position facing the second side surface of the semiconductor light emitting element and projecting toward the second side surface,
The first reflecting surface is an inclined surface that increases a distance from the semiconductor light emitting element according to a direction from the substrate toward the light emitting surface.
The second reflecting surface is a surface that minimizes the distance from the center of the semiconductor light emitting element and increases the distance from the semiconductor light emitting element as the distance from the center increases, and emits light from the second side surface to the first side. A light emitting device characterized by being able to reflect to a reflecting surface.   The light-emitting device according to claim 1, wherein a plurality of the semiconductor light-emitting elements are linearly arranged on the substrate. A substrate, and a semiconductor light emitting element group in which at least two or more semiconductor light emitting elements provided on the substrate are linearly arranged,
The plurality of semiconductor light emitting element groups are provided so that their arrangement directions are parallel,
A first reflecting surface provided at a position facing the first side surface of the semiconductor light emitting element; a second reflecting surface provided at a position facing the second side surface of the semiconductor light emitting element and projecting toward the second side surface; Including,
The first reflecting surface is an inclined surface that increases a distance from the semiconductor light emitting element according to an upward direction of the substrate.
The second reflecting surface is a surface that minimizes the distance from the center of the semiconductor light emitting element and increases the distance from the semiconductor light emitting element as the distance from the center increases, and emits light from the second side surface to the first side. A light-emitting device that is reflected on a reflecting surface.   4. The light emitting device according to claim 3, wherein, when viewed in a plan view, the semiconductor light emitting elements constituting each of the semiconductor light emitting element groups are arranged so as not to be adjacent to each other between the adjacent semiconductor light emitting element groups.   The said 2nd reflective surface is a surface which can reflect the light emission from the said 2nd side surface in the direction parallel to this 2nd side surface, The any one of Claims 1-4 characterized by the above-mentioned. Light emitting device.   6. The maximum height of the first reflecting surface along a direction from the substrate toward the light emitting surface is higher than an upper surface of the semiconductor light emitting element intersecting with the direction. The light emitting device according to any one of the above.   7. The height of the second reflection surface is higher than the upper surface of the semiconductor light emitting element and lower than the first reflection surface. 7. Light emitting device.   The light emitting device according to claim 1, further comprising a continuous peripheral wall surrounding the semiconductor light emitting element, the first reflecting surface, and the second reflecting surface.   The light emitting device according to claim 1, wherein the semiconductor light emitting element is covered with a translucent resin. A plurality of the semiconductor light emitting elements are arranged in a line on the substrate,
A translucent first resin embedded between the semiconductor light emitting elements;
On the first resin, the second resin containing a phosphor that converts light emitted from the semiconductor light emitting element into light of another wavelength,
10. The light-emitting device according to claim 1, wherein an upper surface of the second resin is positioned lower than the peripheral wall. The substrate is provided with a conductive pattern electrically connected to the semiconductor light emitting element,
The semiconductor light emitting element is either a blue light emitting element or an ultraviolet light emitting element,
The light emitting device according to claim 1, wherein a surface of the conductive pattern is silver.   The light-emitting device according to claim 1, wherein at least one of the first reflecting surface and the second reflecting surface is silver.

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