JP7213454B2 - light emitting module - Google Patents

Description

The present invention relates to light emitting modules.

2. Description of the Related Art A light-emitting module in which a light-emitting element such as a light-emitting diode and a light guide plate are combined is widely used as a surface light source such as a backlight of a liquid crystal display. For example, in a direct type backlight in which light-emitting elements are arranged directly under a light guide plate, the brightness in the vicinity of the light-emitting elements tends to be locally high. Therefore, for example, Patent Document 1 discloses a backlight in which a reflecting sheet is provided on the surface of the light guide plate opposite to the light emitting surface, and a light scattering structure is provided on the light incident surface of the light guide plate facing the light emitting elements. disclosed.

For example, as the liquid crystal display becomes thinner, the light guide plate becomes thinner and the brightness of the light emitting element becomes higher.

WO2010/113361

SUMMARY OF THE INVENTION An object of the present invention is to provide a light-emitting module capable of reducing luminance unevenness within a light-emitting surface.

According to one aspect of the present invention, the light-emitting module includes a first surface, a second surface opposite to the first surface, and a recess provided in the second surface, or the first surface and the second surface. a light guide plate having a through portion penetrating between the light guide plate, a light emitting device disposed in the recess or the through portion on the second surface side of the light guide plate, and provided in the recess or the through portion a light-transmitting member covering the side surface of the light-emitting device; a first light-reflecting member provided on the lower surface of the light-transmitting member; and a second light reflective member provided. The first light reflective member is a resin member containing a light diffusing material, the content of the light diffusing material is higher than that of the second light reflective member, and the light emitting device in the first light reflective member is higher than the diffuse reflectance of the light emitted by the light emitting device in the second light reflecting member .

ADVANTAGE OF THE INVENTION According to this invention, the light emitting module which can reduce the brightness nonuniformity in a light emission surface can be provided.

1 is a schematic cross-sectional view of a light-emitting module according to one embodiment of the present invention; FIG. FIG. 2 is an enlarged cross-sectional view of part of the light emitting module shown in FIG. 1; 1 is a schematic cross-sectional view of a light-emitting device in a light-emitting module according to one embodiment of the present invention; FIG. 1 is a schematic cross-sectional view of a light-emitting device in a light-emitting module according to one embodiment of the present invention; FIG. 2 is a schematic cross-sectional view showing a state in which the light emitting module shown in FIG. 1 is connected to a wiring board; FIG. FIG. 5 is a schematic cross-sectional view further enlarging a part of the light emitting module shown in FIG. 4; 1. It is a schematic cross section which shows the manufacturing method of the light emitting module shown in FIG. 1. It is a schematic cross section which shows the manufacturing method of the light emitting module shown in FIG. 1. It is a schematic cross section which shows the manufacturing method of the light emitting module shown in FIG. 1. It is a schematic cross section which shows the manufacturing method of the light emitting module shown in FIG. 1. It is a schematic cross section which shows the manufacturing method of the light emitting module shown in FIG. 1. It is a schematic cross section which shows the manufacturing method of the light emitting module shown in FIG. 1. It is a schematic cross section which shows the manufacturing method of the light emitting module shown in FIG. 1. It is a schematic cross section which shows the manufacturing method of the light emitting module shown in FIG. 5A and 5B are schematic cross-sectional views showing a method of manufacturing the light-emitting module shown in FIG. 4; FIG. 4 is a schematic cross-sectional view of a light-emitting module according to another embodiment of the invention; 16 is an enlarged cross-sectional view of part of the light emitting module shown in FIG. 15; FIG. 16A and 16B are schematic cross-sectional views showing a method of manufacturing the light-emitting module shown in FIG. 15; 16A and 16B are schematic cross-sectional views showing a method of manufacturing the light-emitting module shown in FIG. 15; 16A and 16B are schematic cross-sectional views showing a method of manufacturing the light-emitting module shown in FIG. 15; 16A and 16B are schematic cross-sectional views showing a method of manufacturing the light-emitting module shown in FIG. 15; 16A and 16B are schematic cross-sectional views showing a method of manufacturing the light-emitting module shown in FIG. 15; 16A and 16B are schematic cross-sectional views showing a method of manufacturing the light-emitting module shown in FIG. 15; 16A and 16B are schematic cross-sectional views showing a method of manufacturing the light-emitting module shown in FIG. 15; 16A and 16B are schematic cross-sectional views showing a method of manufacturing the light-emitting module shown in FIG. 15; 16A and 16B are schematic cross-sectional views showing a method of manufacturing the light-emitting module shown in FIG. 15; FIG. 10 is a schematic plan view of a light-emitting module according to still another embodiment of the present invention; FIG. 10 is a schematic plan view of a light-emitting module according to still another embodiment of the present invention;

Hereinafter, embodiments will be described with reference to the drawings. In addition, the same code|symbol is attached|subjected to the same element in each drawing.

FIG. 1 is a schematic cross-sectional view of a light-emitting module 1 according to one embodiment of the invention.
FIG. 2 is an enlarged cross-sectional view of part of the light emitting module 1 shown in FIG.

The light emitting module 1 includes a light guide plate 10, a light emitting device 20, a first light reflecting member 41, a second light reflecting member 42, a third light reflecting member 43, and a fourth light reflecting member 44. have

The light emitting device 20 has a light emitting element 21 and a translucent member 22 . The translucent member 22 contains phosphor, for example. The light guide plate 10 has transparency to the light emitted by the light emitting device 20 . In this specification, the light emitted by the light emitting device 20 represents the light emitted by the light emitting element 21 and the light emitted by the phosphor contained in the translucent member 22 . If the light-emitting device 20 does not contain a phosphor, the light emitted by the light-emitting device 20 represents the light emitted by the light-emitting element 21 . A phosphor sheet may be provided on the first surface 11 of the light guide plate 10 when the translucent member 22 of the light emitting device 20 does not contain phosphor. Alternatively, the light emitting device 20 may be configured with only the light emitting element 21 .

Examples of materials for the light guide plate 10 include thermoplastic resins such as acrylic, polycarbonate, cyclic polyolefin, polyethylene terephthalate, and polyester, thermosetting resins such as epoxy and silicone, and glass.

The light guide plate 10 has a first surface 11 serving as a light emitting surface of the light emitting module 1 and a second surface 12 opposite to the first surface 11 . Furthermore, the light guide plate 10 has a concave portion 13 on the second surface 12 side. The light emitting device 20 is arranged in the recess 13 . The thickness of the light guide plate 10 is preferably 200 μm or more and 800 μm or less. The light guide plate 10 may be composed of a single layer or a laminate of a plurality of layers in its thickness direction. When the light guide plate 10 is composed of a laminate, a translucent adhesive layer may be provided between each layer. Each layer of the laminate may use a different type of base material.

FIG. 3A is a schematic cross-sectional view of the light emitting device 20. FIG.

The light emitting device 20 has a light emitting element 21 . The light emitting element 21 has a semiconductor laminated structure. The light emitting element 21 includes, for example, In _x Al _y Ga _1-xy N (0≦x, 0≦y, X+Y≦1) as a semiconductor laminated structure, and can emit blue light. An element that emits light other than blue may be used as the light emitting element 21 . Further, light emitting elements 21 that emit light of different colors may be used as the light emitting elements 21 that constitute the plurality of light emitting devices 20 .

A translucent member 22 is provided on the main light emitting surface 21 a of the light emitting element 21 . The light emitting element 21 is adhered to the translucent member 22 with a translucent adhesive member 24 . The translucent member 22 covers the main light-emitting surface 21 a of the light-emitting element 21 and extends outside the side surface 21 b of the light-emitting element 21 .

As a material for the translucent member 22, for example, silicone resin, epoxy resin, glass, or the like can be used. The translucent member 22 is, for example, a phosphor layer, and phosphor is dispersed in the translucent member 22 . The phosphor is excited by the light emitted by the light emitting element 21 and emits light with a wavelength different from the wavelength of the light emitted by the light emitting element 21 . For example, a YAG phosphor, a β-sialon phosphor, a fluoride phosphor such as a KSF phosphor or an MGF phosphor, a nitride phosphor such as a CASN phosphor, or the like can be used as the phosphor. Translucent member 22 may contain a plurality of types of phosphors. Also, a plurality of layers of the phosphor may be laminated.

Alternatively, as shown in FIG. 3B, the translucent member 22 containing the phosphor in the light emitting device 20 may cover the main light emitting surface (upper surface) 21a and side surfaces 21b of the light emitting element 21 .

A pair of positive and negative electrodes 23 are provided on the opposite side of the main light emitting surface 21 a of the light emitting element 21 . A side surface 21 b of the light emitting element 21 is covered with a sixth light reflecting member 26 . The sixth light reflective member 26 is also provided on the lower surface of the light emitting element 21 so that the surfaces of the pair of electrodes 23 on the lower surface of the light emitting element 21 (lower surface in FIG. 3) are exposed. The sixth light reflecting member 26 may cover the side surface 21 b of the light emitting element 21 and the side surface of the translucent member 22 .

As shown in FIG. 2, the light-emitting element 21 is positioned closer to the second surface 12 than the light-transmitting member 22, and the light-transmitting member 22 is positioned closer to the first surface 11 than the light-emitting element 21. .

A light-transmitting member 31 is provided between the side wall 13a of the recess 13 in which the light-emitting device 20 is arranged and the side surface of the light-emitting device 20 (the side surface of the light-transmitting member 22 and the side surface of the sixth light-reflecting member 26). is provided. The light transmitting member 31 fixes the light emitting device 20 to the light guide plate 10 . A plurality of light emitting devices 20 are fixed to one light guide plate 10 . Alternatively, one light emitting device 20 may be fixed to one light guide plate 10 .

The light-transmissive member 31 has transparency to the light emitted by the light-emitting device 20, and can be made of, for example, the same resin as the material of the light guide plate 10, or a resin having a small difference in refractive index from the material of the light guide plate 10. . Alternatively, glass may be used as the material of the light transmissive member 31 .

It is preferable that no space such as an air layer is formed between the side surface of the light emitting device 20 and the light transmissive member 31 and between the side wall 13 a of the recess 13 and the light transmissive member 31 . When an air layer does not intervene between the side surface of the translucent member 22 of the light emitting device 20 and the light guide plate 10, and the air layer intervenes to compensate for the difference in refractive index between the translucent member 22 and the light guide plate 10. , and the efficiency of taking in light from the translucent member 22 to the light guide plate 10 can be improved.

A concave portion 15 is formed in a portion facing the light emitting device 20 on the first surface 11 side of the light guide plate 10 , and a fourth light reflecting member 44 is provided in the concave portion 15 . The size of the concave portion 15 in plan view is larger than the size in plan view of the concave portion 13 on the second surface 12 side where the light emitting device 20 is arranged.

A first light reflecting member 41 is provided around the light emitting device 20 on the second surface 12 side of the light guide plate 10 . The first light-reflecting member 41 is provided below the light-transmitting member 31 and on the side surface of the sixth light-reflecting member 26, and is not provided on the side surface of the light-transmitting member 22 containing the phosphor. A side surface of the translucent member 22 is covered with a translucent member 31 . The first light reflecting member 41 is provided on the second surface 12 around the recess 13 .

A second light reflecting member 42 is provided outside the first light reflecting member 41 on the second surface 12 of the light guide plate 10 . The second light reflective member 42 is attached to the second surface 12 with the adhesive layer 33 . The adhesive layer 33 is, for example, a resin layer having transparency to the light emitted by the light emitting device 20 .

The light guide plate 10 has side surfaces 14 that are inclined with respect to the first surface 11 and the second surface 12 . The side surface 14 and the second surface 12 form, for example, an obtuse angle and are continuous. A third light reflecting member 43 is provided on the side surface 14 . The third light reflecting member 43 is also provided on part of the second surface 12 so as to cover the corner formed by the side surface 14 and the second surface 12 .

The second light reflecting member 42 is provided between the first light reflecting member 41 and the third light reflecting member 43 provided on a portion of the second surface 12 . Also, as shown in FIG. 1 , the second light reflecting member 42 is provided on the second surface 12 between the first light reflecting members 41 between the plurality of light emitting devices 20 . The boundary between the first light reflecting member 41 and the second light reflecting member 42 is located at a position overlapping the fourth light reflecting member 44 in the thickness direction of the light guide plate 10 . The thickness of the second light reflecting member 42 is preferably 35 μm or more and 350 μm or less.

As shown in FIG. 2, wiring 51 is provided on the bottom surface of the second light reflecting member 42, the bottom surface of the first light reflecting member 41, and the bottom surface of the sixth light reflecting member . The wiring 51 is connected to the electrode 23 of the light emitting element 21 . The wiring 51 is separated between the pair of electrodes 23 .

FIG. 4 shows a state in which the light emitting module 1 is connected to the wiring board 50. As shown in FIG. FIG. 5 is an enlarged sectional view further enlarging a part of the light emitting module 1 shown in FIG. A wiring board 50 is attached to the wiring 51 . The wiring board 50 is, for example, a flexible wiring board. As shown in FIG. 3 , the wiring board 50 has a substrate 52 , wiring 53 and conductive vias 54 . An insulating base material 52 is provided between the wiring 51 and the wiring 53 . The base material 52 is also attached to the lower surface of the third light reflecting member 43 .

The conductive via 54 penetrates the base material 52 and connects the wiring 51 and the wiring 53 . An insulating film 55 is provided on the surface of the wiring 53 .

As shown in FIGS. 1 and 2, a recess 16 is formed in a region of the first surface 11 of the light guide plate 10 facing the second light reflecting member 42 . Alternatively, a convex portion may be formed on the first surface 11 of the light guide plate 10 . The concave portion 16 (or convex portion) is formed, for example, concentrically around the concave portion 15 facing the light emitting device 20 . Alternatively, the concave portions 16 (or convex portions) may be formed in a dot shape. The concave portion 16 (or convex portion) functions as a prism that refracts and reflects light.

The first light reflective member 41, the third light reflective member 43, the fourth light reflective member 44, and the sixth light reflective member 26 are, for example, white resin members containing a light diffusing material. The first light-reflecting member 41, the third light-reflecting member 43, the fourth light-reflecting member 44, and the sixth light-reflecting member 26 are made of, for example, silicone resin or epoxy resin containing titanium oxide as a light diffusing material. It is a member.

The second light reflecting member 42 includes, for example, a laminated film of a plurality of insulating films. As this insulating film, for example, a polyester-based resin can be used. The second light reflecting member 42 does not contain a light diffusing material. Alternatively, the content rate (weight percentage) of the light diffusing material in the second light reflecting member 42 is the same as the first light reflecting member 41, the third light reflecting member 43, the fourth light reflecting member 44, and the sixth light reflecting member It is less than the content (weight percent) of the light diffusing material in each of the reflective members 26 . Also, the second light reflecting member 42 may be white polyethylene terephthalate containing titanium oxide as a light diffusing material, or white polyethylene terephthalate in which a large number of voids are formed.

The diffuse reflectance of the light emitted by the light emitting device 20 in each of the first light reflecting member 41, the third light reflecting member 43, the fourth light reflecting member 44, and the sixth light reflecting member 26 is the second light It is higher than the diffuse reflectance of the light emitted by the light emitting device 20 in the reflective member 42 . Diffuse reflectance can be measured, for example, with a high-speed spectral colorimeter (CMS-35SP) manufactured by Murakami Color Research Laboratory.

The diffuse reflectance of the light emitted by the light emitting device 20 on each of the first light reflecting member 41, the third light reflecting member 43, the fourth light reflecting member 44, and the sixth light reflecting member 26 is specular reflection. higher than the rate. The diffuse reflectance of the light emitted by the light emitting device 20 on the second light reflecting member 42 is lower than the specular reflectance.

The content rate of the light diffusing material in the fourth light reflective member 44 is higher than the content rate of the light diffusing material in each of the first light reflective member 41, the third light reflective member 43, and the sixth light reflective member 26. is also low. Therefore, the transmittance of the light emitted by the light emitting device 20 in the fourth light reflecting member 44 is the light emitting device in each of the first light reflecting member 41, the third light reflecting member 43 and the sixth light reflecting member 26. 20 is higher than the transmittance for the light emitted.

The fourth light reflecting member 44 diffuses downward and laterally the light emitted upward from the light emitting device 20 while appropriately transmitting the light. That is, the fourth light-reflecting member 44 prevents the area directly above the light-emitting device 20 from becoming too dark or too bright on the light-emitting surface (first surface 11) of the light-emitting module 1 .

The light emitted from the light emitting device 20 toward the second surface 12 is diffusely reflected upward by the first light reflecting member 41, and the brightness of the light extracted from the first surface 11, which is the light emitting surface, can be improved.

The sixth light reflecting member 26 provided on the side surface of the light emitting element 21 suppresses light from the light emitting element 21 entering the light guide plate 10 without passing through the translucent member 22 containing phosphor.

The first light-reflecting member 41 and the sixth light-reflecting member 26 suppress the base material 52 of the wiring board 50 near the light emitting device 20 from being exposed to the light of the light emitting element 21, thereby preventing deterioration of the base material 52. can be prevented.

Part of the light diffusely reflected by the first light reflecting member 41 and the fourth light reflecting member 44 travels toward the second light reflecting member 42 and the first surface 11 . In the region between the second light reflective member 42 and the first surface 11, specular reflection on the second light reflective member 42 and total reflection on the first surface 11 are repeated. Light from the light guide plate 10 is guided through the light guide plate 10 toward the side surface 14 of the light guide plate 10 . A portion of the light directed toward the first surface 11 is extracted from the first surface 11 to the outside of the light guide plate 10 .

As the second light reflective member 42, by using a material that has a higher specular reflection characteristic than a diffuse reflection characteristic of the light emitted from the light emitting device 20, the light can be easily guided to the end (side surface 14) of the light guide plate 10. can. Even if the distance between the light emitting device 20 and the side surface 14 of the light guide plate 10 or the distance between the plurality of light emitting devices 20 is increased, light can be easily guided to the entire area of the light guide plate 10 . This can reduce luminance unevenness in the light emitting surface (first surface 11). In addition, the number of light emitting devices 20 arranged on the light guide plate 10 can be reduced.

The light guided to the side surface 14 of the light guide plate 10 is diffusely reflected toward the first surface 11 by the third light reflecting member 43 provided on the side surface 14 , and is reflected in the first direction in a region near the edge of the light guide plate 10 . The brightness of light extracted from the first surface 11 can be improved.

Further, in a configuration in which a plurality of light emitting modules 1 are arranged adjacently to realize a surface light source having a wider light emitting surface, the third light reflecting member 43 suppresses light guiding between adjacent light emitting modules 1 . For example, light guiding from the light-emitting module 1 in the light-emitting state to the light-emitting module 1 in the non-light-emitting state is restricted.

Next, a method for manufacturing the light-emitting module 1 of the embodiment will be described with reference to FIGS. 6 to 14. FIG.

As shown in FIG. 6, a light guide plate 10 is prepared. A concave portion 15 is formed on the first surface 11 side of the light guide plate 10 and a concave portion 13 is formed on the second surface 12 side.

As shown in FIG. 7, a fourth light reflecting member 44 is formed in the concave portion 15. As shown in FIG.

After forming the fourth light reflecting member 44, the sheet-like second light reflecting member 42 is adhered to the second surface 12 with the adhesive layer 33, as shown in FIG.

After attaching the second light reflecting member 42 to the second surface 12, the light transmitting member 31 is supplied to the concave portion 13 as shown in FIG. The light transmissive member 31 is, for example, liquid resin.

As shown in FIG. 10, the light emitting device 20 is arranged in the concave portion 13 to which the light transmissive member 31 is supplied. A translucent member 22 in the light emitting device 20 is placed on the bottom surface of the recess 13 . After that, the liquid light-transmitting member 31 is cured, and the light-emitting device 20 is fixed to the light guide plate 10 by the light-transmitting member 31 .

After fixing the light emitting device 20 to the light guide plate 10, the first light reflecting member 41 is formed around the light emitting device 20 on the second surface 12, as shown in FIG. The first light reflecting member 41 is provided on the second surface 12 in the region between the second light reflecting member 42 and the sixth light reflecting member 26 of the light emitting device 20 so as to cover the light transmitting member 31. It is formed.

When forming the second light reflecting member 42, a third light reflecting member 43 is also formed on the side surface 14 of the light guide plate 10 shown in FIG.

As shown in FIG. 12, wiring is provided on the second light reflecting member 42, the first light reflecting member 41, and the sixth light reflecting member 26 so as to be connected to the electrodes 23 of the light emitting device 20. 51 is formed.

The wiring 51 is not formed on the sixth light reflective member 26 between the pair of positive and negative electrodes 23 . As shown in FIG. 13, an insulating film 32 is formed on the sixth light reflective member 26 between the pair of electrodes 23 in order to improve the insulation between the pair of electrodes 23 .

As shown in FIG. 14 , when connecting the light-emitting module 1 to the wiring board 50 , the base material 52 of the wiring board 50 is attached to the wiring 51 . After that, the conductive vias 54 shown in FIG. 5 are formed, and an insulating film 55 covering the wirings 53 of the wiring board 50 and the conductive vias 54 is formed.

Here, as a comparative example, a light guide plate 10 having a plurality of concave portions 13 formed therein is attached to a structure in which a plurality of light emitting devices 20 are mounted on a wiring board 50 in advance, so that the light emitting devices 20 are mounted in the concave portions 13 . In the arrangement, high accuracy is required between the mounting positions of the plurality of light emitting devices 20 on the wiring board 50 and the positions of the plurality of recesses 13 in the light guide plate 10 .

On the other hand, according to the embodiment, since the light guide plate 10 holds the light emitting device 20 instead of the wiring board 50 and the light guide plate 10 and the light emitting device 20 are integrally configured, The light emitting device 20 can be arranged with high positional accuracy. This suppresses unevenness in luminance distribution within the light emitting surface of the light guide plate 10 .

FIG. 15 is a schematic cross-sectional view of a light-emitting module 2 according to another embodiment of the invention.
16 is an enlarged sectional view of part of the light emitting module 2 shown in FIG. 15. FIG.
The same reference numerals are given to the same elements as in the light emitting module 1 of the above-described embodiment.

The light emitting module 2 includes a light guide plate 10, a light emitting device 20, a first light reflecting member 141, a second light reflecting member 42, a third light reflecting member 143, and a fourth light reflecting member 44. , a fifth light-reflecting member 45 .

The light guide plate 10 has a penetrating portion 113 penetrating between the first surface 11 and the second surface 12 . The light emitting device 20 is arranged in the through portion 113 . In the light-emitting device 20 , the light-emitting element 21 is positioned closer to the second surface 12 than the translucent member 22 , and the translucent member 22 is positioned closer to the first surface 11 than the light-emitting element 21 .

A light transmissive member 131 is provided between the side wall 113a of the penetrating portion 113 and the side surface of the light emitting device 20 (the side surface of the translucent member 22 and the side surface of the sixth light reflecting member 26). The light transmitting member 131 fixes the light emitting device 20 to the light guide plate 10 .

The light-transmissive member 131 has transparency to the light emitted by the light-emitting device 20, and can be made of, for example, the same resin as the material of the light guide plate 10, or a resin having a small difference in refractive index from the material of the light guide plate 10. . Alternatively, glass may be used as the material of the light transmissive member 131 .

A space such as an air layer is not formed between the side surface of the light emitting device 20 and the light transmissive member 131 and between the side wall 113 a of the penetrating portion 113 and the light transmissive member 131 . Since no air layer is interposed between the side surface of the light-transmitting member 22 of the light-emitting device 20 and the light guide plate 10, the refractive index difference between the light-transmitting member 22 and the light guide plate 10 is smaller than in the case where the air layer is interposed. can be made smaller, and the efficiency of taking in light from the translucent member 22 to the light guide plate 10 can be improved.

A concave portion 15 is formed in a portion facing the light emitting device 20 on the first surface 11 side of the light guide plate 10 , and a fourth light reflecting member 44 is provided in the concave portion 15 .

A fifth light reflecting member 45 is provided on the upper surface of the translucent member 22 , which is the upper surface of the light emitting device 20 . The light transmissive member 131 is also provided between the fifth light reflecting member 45 and the fourth light reflecting member 44 so as to cover the fifth light reflecting member 45 .

A first light reflecting member 141 is provided around the light emitting device 20 on the second surface 12 side of the light guide plate 10 . The first light reflecting member 141 is provided below the light transmitting member 131 and on the side surface of the sixth light reflecting member 26 of the light emitting device 20, and is provided on the side surface of the light transmitting member 22 containing phosphor. not A side surface of the translucent member 22 is covered with a translucent member 131 .

A second light reflecting member 42 is provided outside the first light reflecting member 141 on the second surface 12 of the light guide plate 10 . The second light reflective member 42 is attached to the second surface 12 with the adhesive layer 33 .

The second light reflecting member 42 extends to the edge of the light guide plate 10 . The second light reflective member 42 is provided on the second surface 12 between the first light reflective members 141 between the plurality of light emitting devices 20 . The boundary between the first light reflecting member 141 and the second light reflecting member 42 is located at a position overlapping the fourth light reflecting member 44 in the thickness direction of the light guide plate 10 .

The light guide plate 10 has side surfaces 114 inclined with respect to the first surface 11 and the second surface 12 . The side surface 114 and the first surface 11 form an obtuse angle, for example. A third light reflecting member 143 is provided on the side surface 114 .

As shown in FIG. 16, wiring 51 is provided on the bottom surface of the second light reflecting member 42, the bottom surface of the first light reflecting member 141, and the bottom surface of the sixth light reflecting member 26. As shown in FIG. The wiring 51 is connected to the electrode 23 of the light emitting element 21 . The wiring board 50 described above with reference to FIG. 4 is attached to the wiring 51 .

As shown in FIGS. 15 and 16 , a recess 16 is formed in a region of the first surface 11 of the light guide plate 10 facing the second light reflecting member 42 . Alternatively, a convex portion may be formed on the first surface 11 of the light guide plate 10 . The concave portion 16 (or convex portion) is formed, for example, concentrically around the concave portion 15 facing the light emitting device 20 . Alternatively, the concave portions 16 (or convex portions) may be formed in a dot shape. The concave portion 16 (or convex portion) functions as a prism that refracts and reflects light.

The first light-reflecting member 141, the third light-reflecting member 143, the fourth light-reflecting member 44, the fifth light-reflecting member 45, and the sixth light-reflecting member 26 are, for example, a white light containing a light diffusing material. is a resin member. The first light-reflecting member 141, the third light-reflecting member 143, the fourth light-reflecting member 44, the fifth light-reflecting member 45, and the sixth light-reflecting member 26 are made of, for example, titanium oxide as a light diffusing material. It is a member of silicone resin or epoxy resin containing.

The second light reflecting member 42 is configured in the same manner as in the above embodiment.

1st light reflecting member 141, third light reflecting member 143, fourth light reflecting member 44, fifth light reflecting member 45, and sixth light reflecting member 26 for light emitted by light emitting device 20 The diffuse reflectance is higher than the diffuse reflectance of the light emitted by the light emitting device 20 in the second light reflecting member 42 .

Each of the first light reflecting member 141, the third light reflecting member 143, the fourth light reflecting member 44, the fifth light reflecting member 45, and the sixth light reflecting member 26 of the light emitted by the light emitting device 20 The diffuse reflectance at is higher than the specular reflectance. The diffuse reflectance of the light emitted by the light emitting device 20 on the second light reflecting member 42 is lower than the specular reflectance.

The content rate (weight percentage) of the light diffusing material in each of the fourth light reflecting member 44 and the fifth light reflecting member 45 is the same as that of the first light reflecting member 141, the third light reflecting member 143, and the sixth light reflecting member 141, the third light reflecting member 143, and the sixth light reflecting member 45. It is less than the content (weight percent) of the light diffusing material in each of the reflective members 26 . Therefore, the transmittance of the light emitted from the light emitting device 20 in each of the fourth light reflecting member 44 and the fifth light reflecting member 45 is the same as that of the first light reflecting member 141, the third light reflecting member 143, and the sixth light reflecting member 143, respectively. It is higher than the transmittance of the light emitted from the light emitting device 20 in each of the light reflecting members 26 .

The fourth light-reflecting member 44 and the fifth light-reflecting member 45 allow the light emitted upward from the light emitting device 20 to pass therethrough appropriately while diffusing the light downward and laterally. That is, the fourth light-reflecting member 44 and the fifth light-reflecting member 45 do not make the region directly above the light emitting device 20 on the light emitting surface (first surface 11) of the light emitting module 1 too dark or too bright. try not to

The light emitted from the light emitting device 20 toward the second surface 12 side is diffusely reflected upward by the first light reflecting member 141, and the brightness of the light extracted from the first surface 11, which is the light emitting surface, can be improved.

The first light-reflecting member 141 and the sixth light-reflecting member 26 suppress the base material 52 of the wiring board 50 near the light emitting device 20 from being exposed to the light of the light emitting element 21, thereby preventing deterioration of the base material 52. can be prevented.

Part of the light diffusely reflected by the first light reflecting member 141, the fourth light reflecting member 44, and the fifth light reflecting member 45 travels toward the second light reflecting member 42 and the first surface 11. . In the region between the second light reflective member 42 and the first surface 11, specular reflection on the second light reflective member 42 and total reflection on the first surface 11 are repeated. Light from the light guide plate 10 is guided through the light guide plate 10 toward the side surface 114 of the light guide plate 10 . A portion of the light directed toward the first surface 11 is extracted from the first surface 11 to the outside of the light guide plate 10 .

As the second light reflective member 42, by using a material that has a higher specular reflection characteristic than a diffuse reflection characteristic of the light emitted from the light emitting device 20, the light can be easily guided to the end (side surface 114) of the light guide plate 10. can. Even if the distance between the light emitting device 20 and the side surface 114 of the light guide plate 10 or the distance between the plurality of light emitting devices 20 is increased, light can be easily guided to the entire area of the light guide plate 10 . This can reduce luminance unevenness in the light emitting surface (first surface 11). In addition, the number of light emitting devices 20 arranged on the light guide plate 10 can be reduced.

The light guided to the side surface 114 of the light guide plate 10 is diffusely reflected toward the first surface 11 by the third light reflecting member 143 provided on the side surface 114 , and is reflected in the first direction in the region near the edge of the light guide plate 10 . The brightness of light extracted from the first surface 11 can be improved.

Further, in a configuration in which a plurality of light emitting modules 2 are arranged adjacently to realize a surface light source having a wider light emitting surface, the third light reflecting member 143 suppresses light guiding between adjacent light emitting modules 2 . For example, the light guide from the light-emitting module 2 in the light-emitting state to the light-emitting module 2 in the non-light-emitting state is restricted.

Next, a method for manufacturing the light emitting module 2 will be described with reference to FIGS. 17 to 25. FIG.

As shown in FIG. 17 , the concave portion 15 is formed on the first surface 11 side of the light guide plate 10 , and the second light reflecting member 42 is attached to the second surface 12 with the adhesive layer 33 .

After attaching the second light reflecting member 42 to the second surface 12, as shown in FIG. A through portion (through hole) 113 penetrating through is formed in the light guide plate 10 .

After forming the penetrating portion 113 , the second surface 12 side of the light guide plate 10 is attached to the sheet 100 as shown in FIG. 19 . A surface of the second light reflecting member 42 is attached to the sheet 100 . The opening of the penetrating portion 113 on the second surface 12 side is closed with the sheet 100 . A portion of the sheet 100 forms the bottom surface of the through portion 113 .

Then, the light emitting device 20 is arranged in the through portion 113 . The electrode 23 and the sixth light reflective member 26 in the light emitting device 20 are attached on the sheet 100 closing the opening of the penetrating portion 113 on the second surface 12 side. A gap exists between the side surface of the light emitting device 20 and the side wall 113 a of the through portion 113 .

After placing the light emitting device 20 in the through portion 113, as shown in FIG. The resin 131' contains a light diffusing material such as titanium oxide.

Then, by a centrifugal method, the light diffusing material contained in the resin 131 ′ is sedimented on the upper surface of the light emitting device 20 and on the sheet 100 that closes the opening of the penetrating portion 113 on the second surface 12 side. The light diffusing material that settles on the sheet 100 settles in a region below the translucent member 22 .

As shown in FIG. 21, due to the precipitation of the light diffusing material, a fifth light reflecting member 45 is formed on the upper surface of the translucent member 22 of the light emitting device 20 and around the second surface 12 side of the light emitting device 20. A first light reflecting member 141 is formed.

After the light diffusing material is allowed to settle, the resin 131' is cured. For example, the resin 131' is thermally cured at a temperature of around 150.degree. The sheet 100 has heat resistance against the temperature at this time.

By curing the resin 131 ′, the light transmitting member 131 is formed on the light emitting device 20 in the through portion 113 and between the light emitting device 20 and the side wall 113 a of the through portion 113 . The device 20 is fixed to the light guide plate 10 .

As shown in FIG. 22 , a fourth light reflecting member 44 is formed in the concave portion 15 above the light transmitting member 131 .

By separating the sheet 100 from the light guide plate 10 to which the light emitting device 20 is fixed, the electrode 23 of the light emitting device 20 is exposed on the second surface 12 side. Then, as shown in FIG. 23, wires 51 are placed on the second light reflecting member 42, the first light reflecting member 141, and the sixth light reflecting member 26 so as to connect to the exposed electrodes 23. It is formed.

The wiring 51 is not formed on the sixth light reflective member 26 between the pair of positive and negative electrodes 23 . As shown in FIG. 24, an insulating film 32 is formed on the sixth light reflective member 26 between the pair of electrodes 23 in order to improve the insulation between the pair of electrodes 23 .

Then, as shown in FIG. 25 , when connecting the light emitting module 2 to the wiring board 50 , the base material 52 of the wiring board 50 is attached to the wiring 51 . After that, the conductive vias 54 shown in FIG. 5 are formed, and an insulating film 55 covering the wirings 53 of the wiring board 50 and the conductive vias 54 is formed.

Also in this embodiment, the light guide plate 10 holds the light emitting device 20 instead of the wiring board 50, and the light guide plate 10 and the light emitting device 20 are integrated. 20 can be placed. This suppresses unevenness in luminance distribution within the light emitting surface of the light guide plate 10 .

In addition, since the penetrating portion 113 is formed after the second light reflecting member 42 is attached to the second surface 12, and the light emitting device 20 is arranged in the penetrating portion 113, the electrode 23 of the light emitting device 20 receives the second light. It is not covered by the reflective member 42. Further, since the resin 131' is supplied into the through portion 113 after the electrodes 23 of the light emitting device 20 are attached to the sheet 100, the electrodes 23 of the light emitting device 20 are not covered with the resin 131'. After the resin 131 ′ is cured, the sheet 100 is peeled off to expose the electrodes 23 of the light emitting device 20 . Therefore, the step of removing the second light reflective member 42 and the resin 131 ′ covering the electrodes 23 of the light emitting device 20 is not required, and the wires 51 can be easily connected to the electrodes 23 .

FIG. 26 is a schematic plan view of a light emitting module 200 according to still another embodiment of the invention.

This light emitting module 200 has a configuration in which a plurality of light emitting modules 1 or 2 described above are arranged. For example, the third light reflecting members 43 and 143 in the light emitting modules 1 and 2 are adjacent to each other. The third light-reflecting members 43, 143 limit light guidance between adjacent light-emitting modules 1, 2. FIG.

FIG. 27 is a schematic plan view of a light emitting module 300 according to still another embodiment of the invention.

This light emitting module 300 has a configuration in which a plurality of light emitting modules 2 shown in FIGS. 15 and 16 are arranged. The third light reflecting members 143 in the light emitting module 2 are adjacent to each other. The third light reflecting member 143 continuously surrounds the light emitting module 2 .

The embodiments of the present invention have been described above with reference to specific examples. However, the invention is not limited to these specific examples. Based on the above-described embodiment of the present invention, all forms that can be implemented by those skilled in the art by appropriately designing and changing are also included in the scope of the present invention as long as they include the gist of the present invention. In addition, within the scope of the idea of the present invention, those skilled in the art can conceive of various modifications and modifications, and it is understood that these modifications and modifications also belong to the scope of the present invention. .

DESCRIPTION OF SYMBOLS 1, 2... Light emitting module 10... Light-guide plate 11... 1st surface 12... 2nd surface 13... Recessed part 20... Light-emitting device 21... Light-emitting element 22... Translucent member 26... Sixth light Reflective member 31, 131... Light transmissive member 41, 141... First light reflecting member 42... Second light reflecting member 43, 143... Third light reflecting member 44... Fourth light reflecting 45... Fifth light reflecting member 51, 53... Wiring 54... Conductive via 113... Through portion 200, 300... Light emitting module

Claims (12)

A conductor having a first surface, a second surface opposite to the first surface, and a recess provided in the second surface or a penetrating portion penetrating between the first surface and the second surface. a light plate;
a light emitting device disposed in the recess or the through portion on the second surface side of the light guide plate;
a light transmissive member provided in the recess or the through portion and covering a side surface of the light emitting device;
a first light reflective member provided on the lower surface of the light transmissive member;
a second light reflective member provided outside the first light reflective member on the second surface;
with
The first light reflective member is a resin member containing a light diffusing material, and has a higher content of the light diffusing material than the second light reflective member,
The light emitting module , wherein the diffuse reflectance of the light emitted from the light emitting device on the first light reflective member is higher than the diffuse reflectance of the light emitted from the light emitting device on the second light reflective member . the diffuse reflectance of the light emitted by the light emitting device on the first light reflective member is higher than the specular reflectance;
2. The light emitting module according to claim 1, wherein the diffuse reflectance of the light emitted from the light emitting device on the second light reflecting member is lower than the specular reflectance. 3. The light emitting module according to claim 1, wherein said second light reflecting member does not contain a light diffusing material. The light emitting module according to any one of claims 1 to 3 , wherein the second light reflecting member includes a laminated film of a plurality of insulating films. further comprising a third light reflective member provided on a side surface of the light guide plate;
5. Any one of claims 1 to 4 , wherein the diffuse reflectance of the light emitted from the light emitting device on the third light reflecting member is higher than the diffuse reflectance of the light emitted from the light emitting device on the second light reflecting member. The light-emitting module according to 1. 6. The light emitting module according to claim 5 , wherein said third light reflecting member is a resin member containing a light diffusing material. The light-transmitting member is provided between a side wall of the recess or the through-hole and a side surface of the light-emitting device, and the light- emitting device is fixed to the light guide plate by the light-transmitting member. 7. The light emitting module according to any one of 1 to 6 . 8. The light-emitting module according to claim 1 , further comprising a fourth light-reflecting member provided on a portion of said light guide plate facing said light-emitting device on said first surface side. 9. The light emitting module according to claim 8 , wherein said fourth light reflecting member is provided on said light transmitting member . 10. The light emitting module according to claim 8 , wherein the fourth light reflecting member is a resin member containing a light diffusing material. 11. The light emitting module according to any one of claims 1 to 10, further comprising a fifth light reflecting member on the upper surface of said light emitting device. The light emitting device
a light emitting element;
a translucent member covering the main light emitting surface of the light emitting element;
a sixth light reflective member covering the side surface of the light emitting element;
The light emitting module according to any one of claims 1 to 11 , having

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