JP7116331B2 - Light-emitting module manufacturing method and light-emitting module - Google Patents

Description

TECHNICAL FIELD The present disclosure relates to a method for manufacturing a light emitting module and a light emitting module.

A light-emitting module using a light guide plate is known.

Korean Patent Publication No. 10-2009-0117419 Japanese Patent Publication No. 2008-503034 JP 2019-012681 A

An object of the present invention is to provide a thin light-emitting module.

A step of preparing a light source having a pair of positive and negative electrodes on the same side;
A light guide plate having a first main surface serving as a light extraction surface, a second main surface opposite to the first main surface, and a plurality of through holes penetrating from the first main surface to the second main surface is prepared. process and
disposing a light adjustment member in the through hole so that an inner surface of the through hole on the second main surface side is exposed, and forming a recess formed by the inner surface and the light adjustment member;
placing the light source on the light adjustment member so as to be spaced apart from the inner surface of the recess, with the electrode facing upward;
disposing a light reflecting member disposed between the inner surface of the recess and the light source and covering the second main surface so as to expose at least a portion of the electrode;
forming a wiring layer electrically connected to the plurality of light emitting elements;
A method of manufacturing a light-emitting module comprising:

a light guide plate including a first principal surface, a second principal surface opposite to the first principal surface, and a through hole penetrating from the first principal surface to the second principal surface;
A light source arranged on the second main surface side in the through hole, comprising: a light emitting element; a first translucent member covering a side surface of the light emitting element; a light source comprising: a light adjusting member;
a second light adjusting member disposed on the first main surface side within the through hole;
a bonding member disposed between the light adjustment member and the light source;
a light reflecting member covering the second main surface,
In the through hole, the light reflecting member is in contact with an inner side surface of the through hole and is not in contact with a side surface of the light source.

A thin light-emitting module can be provided.

1 is a configuration diagram schematically showing each configuration of a liquid crystal display device according to an embodiment; FIG. 1 is a schematic plan view showing an example of a light emitting module according to an embodiment; FIG. 1 is a schematic plan view showing an example of a light emitting module according to an embodiment; FIG. 1 is a schematic plan view showing an example of a light emitting module according to an embodiment; FIG. It is a model bottom view which shows an example of the light emitting module concerning embodiment. FIG. 3B is a schematic cross-sectional view taken along line IIIC-IIIC shown in FIGS. 3A and 3B; FIG. 3D is a schematic enlarged cross-sectional view enlarging the 3D portion shown in FIG. 3C; 1 is a schematic cross-sectional view showing an example of a light source according to an embodiment; FIG. 1 is a schematic cross-sectional view showing an example of a light source according to an embodiment; FIG. 1 is a schematic cross-sectional view showing an example of a light source according to an embodiment; FIG. 1 is a schematic cross-sectional view showing an example of a light source according to an embodiment; FIG. 1 is a schematic cross-sectional view showing an example of a light source according to an embodiment; FIG. FIG. 4A is a schematic cross-sectional view, a schematic plan view, and a schematic bottom view showing an example of the manufacturing process of the light-emitting module according to the embodiment. FIG. 4A is a schematic cross-sectional view showing an example of a manufacturing process of the light-emitting module according to the embodiment; FIG. 4A is a schematic cross-sectional view showing an example of a manufacturing process of the light-emitting module according to the embodiment; FIG. 4A is a schematic cross-sectional view showing an example of a manufacturing process of the light-emitting module according to the embodiment; FIG. 4A is a schematic cross-sectional view showing an example of a manufacturing process of the light-emitting module according to the embodiment; FIG. 4A is a schematic cross-sectional view showing an example of a manufacturing process of the light-emitting module according to the embodiment; FIG. 4A is a schematic cross-sectional view showing an example of a manufacturing process of the light-emitting module according to the embodiment; BRIEF DESCRIPTION OF THE DRAWINGS It is a schematic cross section which shows an example of the planar light source concerning embodiment. 1 is a schematic enlarged cross-sectional view showing an example of a light emitting module according to an embodiment; FIG. 1 is a schematic enlarged cross-sectional view showing an example of a light emitting module according to an embodiment; FIG. FIG. 4A is a schematic cross-sectional view showing an example of a manufacturing process of the light-emitting module according to the embodiment; FIG. 4A is a schematic cross-sectional view showing an example of a manufacturing process of the light-emitting module according to the embodiment; 1 is a schematic cross-sectional view showing an example of a light emitting module according to an embodiment; FIG. FIG. 4A is a schematic cross-sectional view showing an example of a manufacturing process of the light-emitting module according to the embodiment; 1 is a schematic cross-sectional view showing an example of a light emitting module according to an embodiment; FIG. FIG. 18B is a schematic enlarged sectional view enlarging the 18B portion shown in FIG. 18A; FIG. 4A is a schematic cross-sectional view, a schematic plan view, and a schematic bottom view showing an example of the manufacturing process of the light-emitting module according to the embodiment.

The present invention will now be described in detail with reference to the drawings. In the following description, terms indicating specific directions and positions (e.g., "upper", "lower", and other terms including those terms) are used as necessary, but the use of these terms is These terms are used to facilitate understanding of the invention with reference to the drawings, and the technical scope of the invention is not limited by the meaning of these terms. Also, parts with the same reference numerals appearing in a plurality of drawings indicate the same or equivalent parts or members. Further, the same name is used for each member even if the state, shape, etc., are different before and after curing or before and after cutting.

Further, the embodiments shown below are examples of light-emitting modules for embodying the technical idea of the present invention, and the present invention is not limited to the following. In addition, unless there is a specific description, the dimensions, materials, shapes, relative arrangements, etc. of the components described below are not intended to limit the scope of the present invention, but are intended to be examples. It is intended. Moreover, the content described in one embodiment can also be applied to other embodiments. Also, the sizes and positional relationships of members shown in the drawings may be exaggerated for clarity of explanation. In some cases, the cross-sectional view is an end view showing only the form of the cut surface, omitting the portion that can be seen behind the cut surface.

<Liquid crystal display device 1000>
FIG. 1 is a configuration diagram showing each configuration of a liquid crystal display device 1000 according to this embodiment. The liquid crystal display device 1000 shown in FIG. 1 includes a liquid crystal panel 1100, two lens sheets 1210 and 1220, a diffusion sheet 1300, and a planar light source 1400 in order from the top. The liquid crystal display device 1000 according to this embodiment is a so-called direct type liquid crystal display device 1000 in which a planar light source 1400 is arranged below a liquid crystal panel 1100 . The liquid crystal display device 1000 irradiates the liquid crystal panel 1100 with light emitted from the light emitting module 100 . In addition to the above constituent members, a polarizing film, a color filter, DBEF (registered trademark), and other members may be further provided.

<Surface light source>
A planar light source 1400 includes at least one light emitting module 100 and at least one wiring board 200 . The number, size, arrangement, etc. of the light-emitting modules 100 and the wiring boards 200 can be selected according to the size of the liquid crystal panel 1100, the planar light source 1400, and the like.

<Light emitting module>
The light emitting module 100 shown in FIG. 2A shows an example of the light emitting module 100 having substantially the same size as the planar light source 1400, and one planar light source 1400 includes one light emitting module 100. FIG. The light emitting module 100 shown in FIG. 2B is an example of a light emitting module 100 smaller than the planar light source 1400, and one planar light source 1400 includes a plurality of light emitting modules 100. FIG. Hereinafter, the light emitting module 100 shown in FIG. 2B will be described as an example.

(Embodiment 1)
3A to 3D show an example of the light emitting module 100 according to this embodiment. The light emitting module 100 includes a light guide plate 10 and a plurality of light sources 20 arranged in through holes 13 of the light guide plate 10 . The light source 20 has a second surface (lower surface) 20b including the electrode 23, a first surface (upper surface) 20a on the opposite side of the second surface (lower surface) 20b, and the first surface 20a and the second surface (lower surface) 20b. and a side 20c therebetween. The light guide plate 10 has a first main surface 11 serving as a light extraction surface, a second main surface 12 opposite to the first main surface 11, and through holes 13 penetrating from the first main surface 11 to the second main surface 12. And prepare.

A light adjustment member 50 is arranged in the through hole 13 . The light source 20 is arranged directly below the light adjustment member 50 (on the second main surface 12 side) within the through hole 13 . A second main surface 12 of the light guide plate 10 is covered with a light reflecting member 40 . The multiple light sources 20 are electrically connected to the wiring layer 70 . The light reflecting member 40 is also arranged between the side surface 20 c of the light source 20 and the inner side surface 131 of the through hole 13 .

Such a light-emitting module can be obtained by a manufacturing method comprising the following steps.
(1) preparing a light source having a pair of positive and negative electrodes on the same side;
(2) Prepare a light guide plate having a first main surface serving as a light extraction surface, a second main surface opposite to the first main surface, and a plurality of through holes penetrating from the first main surface to the second main surface. process and
(3) arranging the light adjustment member in the through hole so that the inner surface of the through hole on the second main surface side is exposed, and forming a recess formed by the inner surface and the light adjustment member;
(4) placing the light source with the electrodes facing up on the light adjustment member so as to be spaced apart from the inner surface of the recess;
(5) disposing a light reflecting member disposed between the inner surface of the recess and the light source and covering the second main surface so that at least a portion of the electrode is exposed;
(6) forming a wiring layer electrically connected to a plurality of light emitting elements;
Prepare.

Since the light emitting module obtained by the method of the present disclosure has the light source arranged in the through hole, it can be a thin light emitting module. Further, by arranging the light reflecting member between the inner surface of the through hole and the light source, it is possible to suppress the light from the light source from entering from the second main surface of the light guide plate.

A method for manufacturing the light-emitting module according to the first embodiment will be described in detail.

(1) Step of preparing light sources A plurality of light sources are prepared. A necessary number of light sources are prepared according to the size of the light emitting module 100 and the desired optical characteristics. 4A-4E are examples of light sources. The light source has a pair of positive and negative electrodes 23 on the same side. The light source includes a first surface (upper surface) 20a and a second surface (lower surface) 20b opposite to the first surface 20a and including a pair of positive and negative electrodes. A plurality of side surfaces 20c are provided between the first surface 20a and the second surface 20b.

The light source comprises a light emitting element 21 . The light emitting element 21 has a pair of positive and negative electrodes 23 on the same side. The light source can include a light emitting element 21 and a member covering the light emitting element 21, as shown in FIGS. 4A to 4D.

The light source 20 shown in FIG. 4A includes a translucent member (first translucent member) 24 that covers the first surface 22 a of the semiconductor laminate 22 of the light emitting element 21 . The translucent member 24 is joined to the light emitting element 21 by a translucent joining member 25 . The translucent bonding member 25 is arranged between the first surface 22 a of the semiconductor laminate 22 and the translucent member 24 . The translucent bonding member 25 can cover at least part of the side surface 22c of each side surface 22c of the semiconductor laminate 22 . A light-reflective covering member 26 covers at least a portion of the side surface 22c of each side surface 22c of the semiconductor stack 22 . Moreover, when the side surface of the semiconductor laminate 22 is covered with the translucent bonding member 25 , the covering member 26 covers the side surface of the translucent bonding member 25 . Note that the translucent joining member 25 can be omitted. Light from the light source 20 is emitted mainly from the first surface (upper surface) 20a, and is also emitted from part of the side surface 20c (the side surface of the translucent member 24).

A light source 20A shown in FIG. 4B has a structure in which a light adjustment member (first light adjustment member) 27 is provided on the light source 20 shown in FIG. 4A. The light adjustment member 27 is a member that reflects at least part of the light from the light emitting element 21 . By adjusting the transmittance or reflectance of the light adjustment member 27, the light distribution characteristics of the light source 20A can be controlled. Light from the light source 20A is emitted from a first surface (upper surface) 20a and a part of the side surface 20c (the side surface of the translucent member 24 and the side surface of the light adjusting member 27). The light adjustment member can also be applied in other light sources.

When the light-reflective coating member 26 is arranged on the side of the semiconductor laminate 22 as in the light source 20 and the light source 20A, the side surface of the light source (side surface of the coating member) is located in the through hole 13 of the light guide plate 10. and the inner side surface 131 of the through hole 13 , the light emitted from the light source is less likely to return to the gap between the side surface 20 c of the light source and the inner side surface 131 of the through hole 13 . Therefore, the light from the light source can enter the light guide plate 10 efficiently.

In the light source 20B shown in FIG. 4C, the side surface 22c of the semiconductor laminate 22 is covered with the translucent member 24. As shown in FIG. A light adjusting member (first light adjusting member) 27 is arranged on the upper surface of the translucent member 24 above the light emitting element 21 . A light adjusting member (first light adjusting member) 28 is also arranged on the lower surface of the translucent member 24 and the lower surface of the semiconductor laminate 22 . Light from the light source 20B is mainly emitted from the side surface 20c. Further, light is emitted from the first surface 20 a according to the transmittance of the light adjusting member 27 . When such a light source 20B is used, the light emitted from the side surface 20c is reflected by the light reflecting member 40 arranged inside the through hole 13. As shown in FIG. This can suppress the light from the light source 20</b>B from entering the light guide plate 10 from the second main surface 12 .

In the light source 20C shown in FIG. 4D, the first surface 22a, the side surface 22c, and the second surface 22b of the semiconductor laminate 22 of the light emitting element 21 are covered with the translucent member 24. As shown in FIG. The side surfaces of the electrodes 23 are also covered with the translucent member 24 . Light from the light source 20C is emitted from the first surface 20a, the side surface 20c and the second surface 20b. When such a light source 20C is used, the light reflecting member 40 is arranged between the inner side surface 131 of the through-hole 13 and the side surface 20c of the light source 20C, so that the light from the second main surface 12 enters the light guide plate 10. Injection can be suppressed.

The light source 20</b>C has an electrode 23 covered with a metal film 29 . The metal film 29 may be arranged to extend from the bottom surface of the electrode 23 to the bottom surface of the translucent member 24 . In other words, the metal film 29 may have an area larger than the area of the lower surface of the electrode 23 . When the size of the light emitting element 21 is small, the pair of electrodes 23 is also small. Therefore, by providing such a metal film 29, it is possible to facilitate electrical connection with a wiring layer, which will be described later. Other light sources can also be provided with such metal films.

The light source 20D shown in FIG. 4E consists of the light emitting element 21 only. The light emitting element 21 includes a semiconductor laminate 22 and a pair of electrodes 23 provided on the second surface 22b. The first surface 20 a of the light source 20</b>D is the first surface 22 a of the semiconductor laminate 22 of the light emitting element 21 . A second surface 20 b of the light source 20</b>D is the lower surface of the light emitting element 21 electrode 23 . A side surface 20 c of the light source 20</b>D is a side surface 22 c of the semiconductor laminate 22 of the light emitting element 21 . By using only the light emitting element 21 as a light source in this manner, the light emitting module can be produced at low cost.

(2) Step of Preparing Light Guide Plate As shown in FIG. 5, the light guide plate 10 is prepared. The light guide plate 10 is a member that spreads the light from the light source 20 in a planar shape, and has a substantially plate shape having a first main surface 11 serving as a light extraction surface and a second main surface 12 located on the opposite side. It is a member. The light guide plate 10 includes a plurality of through holes 13 penetrating from the first major surface 11 to the second major surface 12 . Here, an example in which one light guide plate 10 has four through holes 13 is shown.

Such a light guide plate 10 can be prepared, for example, by injection molding, transfer molding, thermal transfer, or the like. Further, the through holes 13 of the light guide plate 10, the grooves 15 described later, and the like can be collectively formed when the light guide plate 10 is molded. As a result, misalignment during molding can be reduced. Alternatively, the light guide plate 10 may be prepared by purchasing or molding a translucent plate that does not have the through-holes 13 and the grooves 15 and performing the step of forming the through-holes 13 and the grooves 15 . Alternatively, the light guide plate 10 having the through holes 13 and the grooves 15 may be purchased and prepared.

(3) Step of Arranging Light Adjustment Member in Through Hole and Forming Concave Next, as shown in FIG. 6, the light adjustment member 50 is arranged in the through hole 13 . The light adjustment member 50 is arranged on the side closer to the first main surface 11 . In other words, the light adjustment member 50 is arranged so that the inner surface 131 of the through hole 13 on the second main surface 12 side is exposed. Thereby, the recessed portion 14 configured by the inner side surface 131 of the through hole 13 and the light adjusting member 50 can be formed. The concave portion 14 has an inner side surface 131 of the through hole 13 as a side surface and a bottom surface as the second surface 52 of the light adjustment member 50 .

For the light adjustment member 50, for example, small pieces of the light adjustment member 50 can be prepared by forming a plate-like or sheet-like light adjustment member 50 having a large area and separating the light adjustment member 50 into individual pieces by cutting, punching, or the like. Alternatively, a molded product of the small piece of the light adjustment member 50 can be formed and prepared by a method such as injection molding, transfer molding, or compression molding using a mold or the like. Alternatively, sheets or pieces of molded light conditioning member 50 may be purchased and provided.

It is preferable that the size of the light adjustment member 50 in plan view is substantially the same as the size of the through hole 13, for example. The plan view shape of the light adjustment member 50 is preferably the same as the plan view shape of the through hole 13 .

A first surface (upper surface) 51 or a second surface (lower surface) 52 of the light adjusting member 50 can be a flat surface or a curved surface. Alternatively, the first surface 51 or the second surface 52 of the light adjusting member 50 can be convex or concave.

By providing an adhesive between the light adjustment member 50 and the inner surface of the through hole 13 , the light adjustment member 50 can be fixed inside the through hole 13 . The adhesive can be formed on the inner side surface of the through hole 13 or the side surface of the light adjustment member 50 .

The thickness of the light adjustment member 50 is smaller than the depth of the through hole 13 . For example, the thickness of the light adjustment member 50 can be 10% to 90% of the depth of the through-hole 13 . By arranging the light adjustment member 50 having a thickness smaller than the depth of the through hole 13 in this manner, the concave portion 14 having the second surface 52 of the light adjustment member 50 as the bottom surface and the inner side surface 131 of the through hole 13 as the side surface is formed. can be formed.

The first surface 51 of the light adjusting member 50 can be flush with the first major surface 11 of the light guide plate 10 . Alternatively, the first surface 51 of the light adjusting member 50 may be arranged so as to be separated from the first major surface 11 . The molded light adjustment member 50 can be inserted into the through hole 13 from the opening on the first main surface 11 side or from the opening on the second main surface 12 side.

(4) Step of Placing Light Source Next, the light source 20 is placed on the light adjustment member 50 . The light source 20 is arranged directly on the light adjusting member 50 or via the joining member 30 . When the bonding member 30 is used, the bonding member 30 is placed on the light adjusting member 50 as shown in FIG. 7 before the light source 20 is placed. The liquid bonding member 30 can be placed on the bonding member 30 by a method such as potting, transfer, or printing.

The amount of the joining member 30 can be selected as appropriate. It is preferable that the bonding member 30 be arranged in such an amount that it can come into contact with the entire surface of the first surface 20 a of the light source 20 .

The joining member 30 may be provided on the light source 20 side. For example, a method of picking up the light source 20 with an adsorption member such as an adsorption collet, immersing the first surface 20a of the light source 20 in the liquid bonding member 30, and adhering the bonding member 30 to the light source 20 may be used. .

Next, as shown in FIG. 8 , the light source 20 is placed on the joint member 30 . The light source 20 is arranged so as to be separated from the inner surface 131 of the through hole 13 (recess 14) with the electrode 23 facing upward. Specifically, the light source 20 is arranged so that a gap is formed between the side surface of the light source 20 and the inner side surface 131 of the through hole 13 . Such gaps preferably have the same width at positions symmetrical with respect to the center of the light source 20 in plan view, for example.

(5) Step of Arranging Light Reflecting Member Next, as shown in FIG. 9, the light reflecting member 40 covering the second main surface 12 of the light guide plate 10 and the plurality of light sources 20 is arranged. At this time, the light reflecting member 40 is also arranged in the gap between the inner side surface 131 of the through hole 13 (recess 14 ) and the side surface 20 c of the light source 20 . As a result, the light reflecting member 40 can be integrally formed to cover the second main surface 12 and continue to the inside of the through hole 13 . This allows the light from the light source 20 to enter the light guide plate 10 efficiently. Also, the light reflecting member covering the second main surface 12 of the light guide plate 10 and the light reflecting member arranged in the through hole 13 may be separate bodies. In other words, it is possible to divide the steps, such as arranging the light reflecting member in the through hole 13 and curing it, and then arranging and curing the light reflecting member covering the second main surface 12 . For example, materials having different reflectances can be used for the light reflecting member arranged in the through hole 13 and the light reflecting member covering the second main surface 12 . This makes it possible to adjust the reflectance at a position close to the light source and at a position far from the light source, thereby suppressing in-plane luminance unevenness. The two separately formed light reflecting members may be made of materials having different viscosities, materials, etc., in addition to the reflectances described above.

The light reflecting member 40 can be placed in contact with both the side surface 20 c of the light source 20 and the inner side surface 131 of the through hole 13 within the through hole 13 (recess 14 ). Also, the light reflecting member 40 may be in contact with the joining member 30 . Also, the light reflecting member 40 may be in contact with the bottom surface of the recess 14 , that is, the light adjusting member 50 . Thus, the thickness of the light reflecting member 40 in the through hole 13 (recess 14) can be appropriately selected according to the light distribution characteristics of the light source, the light source pitch, the thickness of the light guide plate, the width of the through hole, and the like. can.

The light reflecting member 40 can be formed by transfer molding, potting, printing, spraying, or the like. In the example shown in FIG. 9, the light reflecting member 40 is formed thick so as to completely cover the upper surfaces of the electrodes 23 of the light source 20 . However, the present invention is not limited to this, and the light reflecting member 40 may be arranged such that at least a portion of the electrode 23 is exposed.

Next, part of the light reflecting member 40 is removed. As a result, the electrodes 23 of the light source 20 are exposed from the light reflecting member 40 as shown in FIG. Methods for removing include a grinding member such as a whetstone, blasting, and the like. If the light source 20 has a metal film 29 (see FIG. 4D) connected to the electrode 23, the covering member 40 may be removed until the metal film 29 is exposed. In either case, the light reflecting member 40 is removed until the conductive member (electrode, metal film) capable of supplying power to the light emitting element 21 of the light source 20 is exposed. If the light reflecting member 40 is arranged so that at least part of the electrode 23 is exposed in advance, the step of removing part of the light reflecting member 40 can be omitted.

(6) Step of Forming Wiring Layer Next, as shown in FIG. 11, a metal film to be the wiring layer 70 is formed on the electrode 23 of the light source 20 and the light reflecting member 40 . The method of forming the wiring layer 70 includes sputtering, plating, printing, bonding of metal foil, and the like.

The wiring layer 70 can be formed in a predetermined pattern by using a mask or the like. Further, by forming a metal film on the entire surface including the electrodes 23 of the light source 20 and the light reflecting member 40 and then partially removing the metal film, the wiring layer 70 having a predetermined pattern can be formed. . Methods for partially removing the metal film include etching and laser light irradiation.

As described above, the light-emitting module 100 as shown in FIG. 11 can be obtained. Further, when forming a plurality of light-emitting modules 100 from one light guide plate at the same time, the light-emitting modules 100 can be obtained by forming the wiring layer 70 and then cutting the light guide plate 10 and the light reflecting member 40 . .

If the light emitting module 100 includes a plurality of light sources 20, they can be wired to be driven independently. Further, the light guide plate 10 is divided into a plurality of ranges, the plurality of light sources 20 mounted within one range is grouped, and the plurality of light sources 20 within one group are electrically connected in series or in parallel. A plurality of such light source groups may be provided by connecting to the same circuit. By performing such grouping, a light-emitting module capable of local dimming can be obtained. For example, in the example shown in FIG. 3B, the four light sources 20 are connected in series on the right two and on the left two. These series-connected two sets are further connected in parallel.

The light-emitting module 100 obtained as described above and the wiring 220 of the wiring substrate 200 can be adhered using an adhesive sheet or the like. Thereby, a planar light source 1400 as shown in FIG. 12 can be obtained. The wiring of the wiring board 200 is electrically connected to the external terminals 71 and 72 (see FIG. 3B) of the wiring layer 70 of the light emitting module 100 . By supplying power, the four light sources 20 can be lit at the same time.

The wiring board 200 may be joined to the light emitting module 100 by any method. For example, a sheet-like adhesive sheet can be placed between the surface of the light reflecting member 40 provided on the opposite side of the light guide plate 10 and the surface of the wiring board 200, and can be bonded by pressure bonding. Moreover, the electrical connection between the wiring of the wiring board 200 and the light source 20 may be made by any method. For example, a conductive member, which is a metal embedded in a via hole, can be melted by applying pressure and heat and joined to the metal film.

(Embodiment 2)
A light-emitting module 100A shown in FIG. 13 has a first principal surface 11, a second principal surface 12 opposite to the first principal surface, and a conductor having a through hole 13 penetrating from the first principal surface 11 to the second principal surface. A light plate 10, a light adjustment member 50 arranged in the through hole 13 on the first main surface 11 side, a light source 20B arranged in the through hole 13 on the second main surface 12 side, the light adjustment member 50 and the light source 20B, and a light reflecting member 40 covering the second main surface 12. As shown in FIG. In the through hole 13, the light reflecting member 40 is in contact with the inner side surface 131 and is not in contact with the side surface 20c of the light source 20B. Differences from the first embodiment will be mainly described.

As described above, in the light source 20B, the side surface of the semiconductor laminate 22 of the light emitting element 21 is covered with the translucent member 24 . In other words, light is emitted from a wide area of the side surface 20c of the light source 20B. When such a light source 20B is used, the side surface 20c of the light source 20B is covered with a translucent bonding member 30, so that the light emitted from the side surface 20c of the light source 20B passes through the through hole 13 through the bonding member 30. It is possible to make it easier to enter the light guide plate 10 from the side surface 131 . Since a part of the light reflecting member 40 is arranged so as to be in contact with the inner side surface 131 of the through hole 13 , the light emitted from the side surface 20 c of the light source 20</b>B is reflected from the second main surface 12 of the light guide plate 10 . Injection into the light guide plate 10 can be suppressed. As a result, it is possible to obtain a light-emitting module in which color unevenness in the vicinity of the light source 20B is reduced in plan view.

In this way, when using the light source 20B in which the translucent member 24 is positioned on the side of the semiconductor laminate 22, the translucent bonding member 30 preferably covers 50% or more of each side surface 20c of the light source 20B. . In particular, it is preferable that the joining member 30 covers 50% or more of the side surface of the translucent member 24 .

When a light source including the light adjusting member 27 on the first surface (upper surface) 20a side is used like the light source 20B, the light reflecting member 40 in the through hole 13 is located below the light adjusting member 27 (second It is preferably located on the side closer to the main surface 12). This makes it difficult for the light reflecting member 40 to block the light emitted from the side surface 20c of the light source 20B.

In this way, when forming the joint member 30 covering the side surface 20c of the light source 20B, it is preferable to prepare the light guide plate 10 having the through holes 13 with a width that is, for example, 1.2 times or more the width of the light source 20B. . A sufficient amount of the bonding member 30 is placed to cover a desired area of the side surface 20c of the light source 20B, and the light source 20B is placed on top of the bonding member 30 and pressed to make the side surface 20c of the light source 20B crawl up. Thereby, it is easy to form the joining member 30 covering the side surface 20c of the light source 20B located inside the through hole 13 .

(Embodiment 3)
The light-emitting module 100B shown in FIG. 14 has a light-transmitting member 60 (first light-transmitting member 60) between the light adjusting member (second light adjusting member 50) 50 and the light source 20B in the through hole 13. It differs from the light emitting module 100A according to the second embodiment in that it is provided.

In such a light emitting module 100B, as shown in FIG. 15A, the light adjusting member 50 is arranged in the through hole 13 of the light guide plate 10 to form the concave portion 14, and then, as shown in FIG. A step of placing a translucent member 60 thereon is provided. The light source is arranged on a translucent member 60 arranged on the light adjusting member 50 . Other steps can be performed in the same manner as in the first or second embodiment.

The method of forming the translucent member 60 includes, for example, a method of dividing a large-area plate-like or sheet-like translucent member 60 into individual pieces by cutting, punching, or the like. Alternatively, it is possible to form a small molded product of the translucent member 60 by injection molding, transfer molding, compression molding, or the like using a mold or the like. The sheet or small piece of the molded translucent member 60 may be purchased and prepared.

By disposing the translucent member 60 between the light adjusting member 50 and the light source, the light emitted from the light source toward the light adjusting member 50 can be easily diffused. Also, when using a light source in which the first surface 20a is composed of the light adjusting member 27 as shown in FIG. 4B or 4C, it is difficult to emit light directly above the light source (in the Z direction). Therefore, less light is emitted from the light adjustment member directly above the light source. In such a case, the translucent member 60 is arranged directly above the light source, so that the light emitted from the adjacent light source can pass through the translucent member 60 . As a result, light is emitted to the outside from the light adjustment member 50 as well, so that it is possible to easily reduce uneven brightness in the plane of the light guide plate.

(Embodiment 4)
A light emitting module 100C shown in FIG. 16 differs from other embodiments in that the lower surface (second surface) 52 of the light adjustment member 50 is convex downward. The light adjustment member 50 having the convex second surface 52 can be molded by transfer molding, compression molding, or the like. Alternatively, it is possible to purchase and use the light adjusting member 50 that is preformed so that the second surface 52 is convex. Alternatively, as shown in FIG. 17, the liquid light adjustment member 50 can be placed in the through hole 13 of the light guide plate 10 using a dispensing nozzle 80 or the like and cured.

The light adjustment member 50 has a convex second surface 52 located on the light source side, so that the light from the light source can be easily spread within the plane of the light guide plate 10 . The second surface 52 of the light adjusting member 50 may have a curved surface in a cross-sectional view as shown in FIG. 16, or may have a linear slope. That is, the light adjustment member 50 can have a shape such as a cone or a square pyramid on the second surface 52 side. When the second surface 52 of the light adjustment member 50 has a convex shape, it is preferable that the center of the second surface 52 be convex so as to be closest to the light source in plan view. Further, in the example shown in FIG. 16, the entire second surface 52 of the light control member 50 is convex. Thereby, the light from the light source can be efficiently reflected sideways. However, not limited to this, a part of the second surface 52 of the light adjusting member 50 may be convex.

(Embodiment 5)
In the light-emitting module 100D shown in FIGS. 18A and 18B, a part of the inner side surface 131 of the through-hole 13 is an inclined surface in cross-sectional view. Specifically, an inner surface 131 of the through hole 13 on the side of the first main surface 11 is an inclined surface in a cross-sectional view. Not limited to this, the entire inner side surface 131 of the through hole 13 may be an inclined surface. Also, instead of the inclined surface, a step may be provided.

The through hole 13 of the light guide plate 10 of the light emitting module 100D has a width (diameter) of the opening on the first main surface 11 side larger than the width (diameter) of the opening on the second main surface 12 side. Furthermore, the through hole 13 includes a portion whose width increases as it approaches the opening on the first main surface 11 side.

19A and 19B are a plan view and a cross-sectional view of the light guide plate 10 used in the light emitting module 100D shown in FIG. 18A. Such a light guide plate 10 is prepared, and a liquid light adjustment member 50 is poured into the through hole 13 from the opening on the second main surface 12 side using a dispensing nozzle 80 in the same manner as the method illustrated in FIG. supply. As a result, the light adjustment member 50 having a shape that protrudes toward the light source 20 and has an inclined surface can be arranged directly above the light source 20 . By providing such a light adjustment member 50, the light from the light source 20 can be spread more efficiently in the horizontal direction.

Alternatively, a preformed small piece of the light adjustment member 50 may be inserted into the through hole 13 from the first main surface 11 side.

Further, the light guide plate 10 shown in FIG. 19 has grooves 15 on the second main surface 12 side. The grooves 15 are arranged between the through holes 13 adjacent to each other in a cross-sectional view. Groove 15 is arranged in a quadrangular annular shape so as to surround through-hole 13 in plan view. A part of the light reflecting member 40 can be placed in the groove 15 as shown in FIG. 18A. Thereby, the light from the light source 20 can be easily reflected toward the first main surface 11 side.

Each member constituting the light emitting module will be described in detail below.

(Light guide plate)
A light guide plate is a translucent member that planarly spreads light from a light source. When the light guide plate has a square shape in plan view, the size in plan view can be, for example, about 1 cm to 200 cm on each side, preferably about 3 cm to 30 cm. Further, the thickness of the light guide plate can be about 0.1 mm to 5 mm, preferably 0.5 mm to 3 mm. In addition, the "thickness" here refers to the thickness when it is assumed that there are no concave portions or convex portions on the first principal surface or the second principal surface, for example. The plan view shape of the light guide plate can be, for example, a quadrangle such as a square or a rectangle. Alternatively, it may be polygonal such as triangular, hexagonal, octagonal, circular, elliptical, or the like. Furthermore, a shape in which these are combined, a shape in which a portion is rounded, a shape in which a portion is missing, or the like can be used.

As a material for the light guide plate, a thermoplastic resin such as acrylic, polycarbonate, cyclic polyolefin, polyethylene terephthalate, or polyester, a resin material such as a thermosetting resin such as epoxy or silicone, or an optically transparent material such as glass is used. be able to. In particular, a thermoplastic resin material is preferable because it can be efficiently manufactured by injection molding. Among them, polycarbonate, which has high transparency and is inexpensive, is preferable. Also, by using an inexpensive material such as polyethylene terephthalate, the cost of the light-emitting module can be reduced. Furthermore, heat resistance can be improved more than polycarbonate.

The light guide plate may be formed of a single layer, or may be formed by laminating a plurality of translucent layers. When laminating|stacking several translucent layers, each layer can be bonded together using an adhesive agent. Further, when a plurality of translucent layers are laminated, some or all of the layers may be provided with through-holes or recesses to provide a structure in which an air layer is provided inside the light guide plate. . As a result, the light can be diffused more easily, and the light-emitting module can have reduced luminance unevenness.

(Light guide plate: through hole)
The through-hole is a portion that penetrates from the first main surface of the light guide plate to the second main surface 1 and in which the light source is arranged.

The plurality of through holes are arranged two-dimensionally in a plan view of the light guide plate. Preferably, the plurality of through-holes are two-dimensionally arranged along two orthogonal directions, that is, the x-direction (horizontal direction) and the y-direction (vertical direction). For example, as shown in FIGS. 2A, 2B, etc., the arrangement pitch of the through-holes in the x-direction and the arrangement pitch in the y-direction may be the same or different. Also, the two directions of arrangement may not be orthogonal. Also, the arrangement pitch in the x direction or the y direction is not limited to equal intervals, and may be uneven intervals. For example, the through-holes may be arranged so that the distance between them increases from the center to the periphery of the light guide plate.

The opening of the through-hole can be circular or elliptical in plan view. Alternatively, it can be a quadrilateral such as a square, rhombus, rectangle, or the like. Further, it can be polygonal such as triangular, hexagonal, octagonal.

(Light guide plate: groove)
The light guide plate can have grooves on the second main surface. The side surface of the groove can function as a reflector that reflects light from the light source arranged in the through hole toward the first main surface 11 side. Therefore, it is preferable that the grooves are arranged around the through-holes so as to surround the through-holes in which the light sources are arranged in plan view.

The side surfaces of the groove may be linear or curved in cross-section, or may be combined. Moreover, when the side surface of the groove is curved, the curvature may be constant, or may have an arbitrary curvature depending on the position.

(light source)
The light emitting device comprises a known semiconductor light emitting device such as a light emitting diode. The light source can include only the light emitting element 21, or a light emitting element and a member covering it.

The composition, emission wavelength, size, number, etc. of the semiconductor laminate of the light-emitting element to be used can be appropriately selected according to the purpose. A light-emitting element that emits light of any wavelength from ultraviolet light to visible light can be selected as the light-emitting element. For example, as a light-emitting element that emits ultraviolet, blue, and green light, a nitride-based semiconductor (In _x Al _y Ga _1-x-y N, 0≦X, 0≦Y, X+Y≦1 ) can be used. Moreover, GaAs, GaP, InP, etc. can be mentioned as a light emitting element that emits red light. Various emission wavelengths can be selected depending on the material of the semiconductor laminate and its crystallinity. The shape of the semiconductor laminate of the light-emitting element can be a quadrangle such as a square or a rectangle, or a polygon such as a triangle or a hexagon in plan view. As for the size of the light emitting element in plan view, the length of one side can be set to 50 μm to 1000 μm, for example. Also, the height of the light emitting element can be set to, for example, 5 μm to 300 μm. For example, Cu, Au, Ni, or the like can be used as the electrode of the light emitting element. The thickness of the electrodes can be, for example, 0.5 μm to 100 μm.

(Light source: translucent member)
The light-transmitting material has a light-transmitting property that allows at least light from the light-emitting element to pass therethrough, and transmits 60% or more, preferably 90% or more of the light emitted from the light-emitting element. As a material for the translucent member, translucent thermosetting resin materials such as epoxy resin and silicone resin can be used.

The translucent member may contain particulate phosphor as a wavelength converting substance in the above resin material. The wavelength-converting substance includes a wavelength-converting substance such as a phosphor that converts the wavelength of light emitted from the light-emitting element into light of a different wavelength. The translucent member may include a single layer or a plurality of layers containing a wavelength conversion substance. Moreover, it is possible to include a laminated structure of a layer containing a wavelength converting substance and a layer substantially free of the wavelength converting substance.

Examples of phosphors include yttrium-aluminum-garnet-based phosphors (e.g., Y3 ₍ Al, Ga) _5O12 :Ce), lutetium-aluminum-garnet-based phosphors ₍ e.g., _{Lu3 (} Al, Ga)5O). ₁₂ :Ce), terbium-aluminum-garnet-based phosphors (e.g., Tb3 ₍ Al,Ga) _5O12 :Ce), β-sialon phosphors (e.g., (Si,Al) _{3 (O,N)4 :} Eu), α-sialon phosphors (e.g., Mz(Si, Al) ₁₂ (O, N) ₁₆ (where 0<z≦2, and M excludes Li, Mg, Ca, Y, and La and Ce) lanthanide element)), nitride phosphors such as CASN phosphors (e.g., CaAlSiN ₃ :Eu) or SCASN phosphors (e.g., (Sr, Ca)AlSiN ₃ :Eu), KSF phosphors (e.g., K ₂ SiF ₆ :Mn) or MGF-based phosphors (for example, 3.5MgO·0.5MgF ₂ ·GeO ₂ :Mn) or other fluoride-based phosphors, or quantum dot phosphors can be used.

One translucent member can contain one type or a plurality of types of phosphors. A plurality of kinds of phosphors may be mixed and used, or may be laminated and used. For example, a light-emitting element that emits bluish light may be used, and a β-sialon phosphor that emits greenish light and a fluoride-based phosphor such as a KSF phosphor that emits reddish light may be included as phosphors. . By using such two kinds of phosphors, the color reproduction range of the light-emitting module can be widened. Also, the phosphor may be a quantum dot.

The phosphor may be arranged in any way inside the translucent member. For example, the phosphor may be distributed substantially uniformly inside the wavelength conversion member, or may be unevenly distributed.

The translucent member may contain a light diffusing substance. Examples of the light diffusing substance include fine particles such as SiO ₂ , TiO ₂ , Al ₂ O ₃ and ZnO.

As the light-transmitting member (second light-transmitting member) arranged in the through hole, the same light-transmitting member (first light-transmitting member) used in the light source described above can be used. The first translucent member and the second translucent member may be the same or different. Alternatively, the first translucent member may contain the wavelength converting substance, and the second translucent member may be substantially free of the wavelength converting substance. Conversely, the second translucent member may contain the wavelength converting substance, and the first translucent member may not substantially contain the wavelength converting substance.

(Light source: covering member)
The covering member is a light reflecting member. The coating member may have a reflectance of, for example, 60% or more, preferably 70% or more, and more preferably 90% or more, with respect to light emitted from the light emitting element. The material of the covering member is preferably a resin material containing a white pigment or the like. In particular, a silicone resin containing titanium oxide is preferred.

(Light source: Translucent joining member)
The translucent joining member is a member that joins the light emitting element and the translucent member. Epoxy resins, silicone resins, mixed resins thereof, and the like can be used as the translucent bonding member.

(Light source: metal film)
The metal film is a conductive material such as a plating layer or a sputtered film that covers the electrodes of the light emitting element. The material of the metal film can have a laminated structure in which, for example, Cu/Ni/Au are laminated in this order. The metal film may be arranged so as to continuously cover a part of the covering member or translucent member that covers the side surfaces of the pair of electrodes and the electrodes.

(joining member)
The joining member is a translucent member that joins the light source and the light guide plate.

As a material for the joining member, epoxy resin, silicone resin, mixed resin thereof, or translucent material such as glass can be used.

(light reflecting member)
The light reflecting member is a light reflecting member that covers the plurality of light sources and the second main surface of the light guide plate. A part of the light reflecting member is also arranged in the through hole. By covering the entire second main surface with the light reflecting member, light from the light source can be efficiently introduced into the light guide plate.

The light reflecting member has a reflectance of 60% or more, preferably 90% or more, with respect to light emitted from the light source. For example, metal, white resin material, DBR film, or the like can be used as the material of the light reflecting member. A white resin material is particularly preferable for the material of the light reflecting member. As a white resin material, for example, a resin material containing titanium oxide as a light-reflecting substance, a foamed resin material, or the like can be used. As the resin material, a translucent thermosetting resin material such as epoxy resin, silicone resin, polyethylene terephthalate, or the like can be used.

(light adjusting member)
It is preferable that the light adjustment member is arranged in the through hole of the light guide plate and has a function of reflecting part of the light from the light source. For example, it has a reflectance of 70% to 90%, preferably 80% to 85%, with respect to light emitted from the light source. For example, a white resin material can be used as the material of the light adjustment member 50 . A white resin material is particularly preferable for the material of the light adjustment member 50 . As a white resin material, for example, a resin material containing titanium oxide as a light-reflecting substance, a foamed resin material, or the like can be used. As the resin material, a translucent thermosetting resin material such as epoxy resin, silicone resin, polyethylene terephthalate, or the like can be used.

(wiring layer)
The wiring layer is a conductive member for supplying power to the light source. For example, Ag, Ag/Cu, Ni/Au, or the like can be used as the wiring layer. The wiring layer may use these materials alone, or may be an alloy containing a plurality of materials, or may have a laminated structure. The thickness of the wiring layer can be, for example, 5 μm to 50 μm.

(wiring board)
The wiring board includes an insulating base material and wiring. The wiring is electrically connected to the plurality of light sources.

A wiring board includes, for example, conductive members filled in a plurality of via holes provided in an insulating base material, and wiring electrically connected to the conductive members on both surface sides of the base material.

The wiring board may have a laminated structure. For example, a metal plate provided with an insulating layer on its surface may be used as the wiring board. Also, the wiring substrate may be a TFT substrate having a plurality of TFTs (Thin-Film Transistors).

Ceramics or resin, for example, can be used as the material of the base material of the wiring board. A resin may be selected as the material for the base material in terms of low cost and ease of molding. Examples of resins include composite materials such as phenol resin, epoxy resin, polyimide resin, BT resin, polyphthalamide (PPA), polyethylene terephthalate (PET), unsaturated polyester, and glass epoxy. Moreover, it may be a rigid substrate or a flexible substrate.

The wiring is, for example, a conductive foil (conductor layer) provided on the substrate and electrically connected to the plurality of light sources. The wiring material preferably has high thermal conductivity. Such materials include, for example, conductive materials such as copper. Also, the wiring can be formed by plating, application of a conductive paste, printing, or the like, and the thickness of the wiring is, for example, about 5 to 50 μm.

A light-emitting module according to the present disclosure can be used, for example, as a backlight for a liquid crystal display device, various display devices, and the like.

DESCRIPTION OF SYMBOLS 1000... Liquid crystal display device 1100... Liquid crystal panel 1210, 1220... Lens sheet 1300... Diffusion sheet 1400... Planar light source 100... Light emitting module 200... Wiring board 210... Base material 220... Wiring 10... Light guide plate 11... First main surface ( light extraction surface)
DESCRIPTION OF SYMBOLS 12... 2nd main surface 13... Through-hole 131... Inner surface of a through-hole (recessed part) 14... Recessed part 15... Groove 20, 20A, 20B, 20C, 20D... Light-emitting device (light source)
20a... First surface (upper surface of light source)
20b: second surface (surface on which electrodes of the light source are formed)
20c... Side (side of light source)
21... Light emitting element (light source)
21a First surface (top surface of light source/top surface of semiconductor laminate)
21b . . . second surface (electrode forming surface of semiconductor laminate)
21c... Side (light source side/semiconductor laminate side)
DESCRIPTION OF SYMBOLS 22... Semiconductor laminated body 23... Electrode 24... Translucent member (1st translucent member/translucent member of light source)
25 Translucent joining member 26 Coating member 27, 28 Light adjusting member (first light adjusting member)
29... Metal film 30... Joining member 40... Light reflecting member 50... Light adjusting member (second light adjusting member)
51 . . . First surface of light adjustment member (first principal surface side of light guide plate)
52 . . . Second surface of light adjustment member (second principal surface side of light guide plate)
60... Translucent member (second translucent member/translucent member in through-hole)
70... Wiring layer 71, 72... External terminal 80... Dispensing nozzle

Claims (11)

A step of preparing a light source having a pair of positive and negative electrodes on the same side;
A light guide plate having a first main surface serving as a light extraction surface, a second main surface opposite to the first main surface, and a plurality of through holes penetrating from the first main surface to the second main surface is prepared. process and
disposing a light adjustment member in the through hole so that an inner surface of the through hole on the second main surface side is exposed, and forming a recess formed by the inner surface and the light adjustment member;
placing the light source on the light adjustment member so as to be spaced apart from the inner surface of the recess, with the electrode facing upward;
disposing a light reflecting member disposed between the inner surface of the recess and the light source and covering the second main surface so that at least a portion of the electrode is exposed;
forming a wiring layer electrically connected to the plurality of light sources ;
A method of manufacturing a light-emitting module comprising: 2. The method of manufacturing a light emitting module according to claim 1, wherein the step of placing the light source includes forming a joining member on the light adjustment member and placing the light source on the joining member. 3. The method of manufacturing a light-emitting module according to claim 2, wherein the joining member covers at least part of the side surface of the light source. The method of manufacturing a light-emitting module according to any one of claims 1 to 3, wherein the light reflecting member is in contact with the inner side surface and the side surface of the light source within the recess. The method of manufacturing a light-emitting module according to any one of claims 1 to 3, wherein the light-reflecting member is in contact with the inner side surface of the concave portion and is not in contact with the inner side surface of the light source. 6. The method of manufacturing a light-emitting module according to claim 1, further comprising the step of placing a translucent member on the light adjusting member after placing the light adjusting member. The light adjustment member has a first surface located on the first main surface side of the light guide plate and a second surface located on the second main surface side of the light guide plate, and the second surface is convex. A method for manufacturing a light-emitting module according to any one of claims 1 to 6. a light guide plate including a first principal surface, a second principal surface opposite to the first principal surface, and a through hole penetrating from the first principal surface to the second principal surface;
A light source arranged on the second main surface side in the through hole, comprising: a light emitting element; a first translucent member covering a side surface of the light emitting element; a light source comprising: a light adjusting member;
a second light adjusting member disposed on the first main surface side within the through hole;
a joining member arranged between the second light adjustment member and the light source;
a light reflecting member covering the second main surface,
In the through hole, the light reflecting member is in contact with an inner side surface of the through hole and is not in contact with a side surface of the light source. 9. The light emitting module according to claim 8, comprising a second translucent member between said second light adjusting member and said joining member. 10. The light emitting module according to claim 8, wherein the second light adjusting member has a convex surface located on the light source side. The light-emitting module according to any one of claims 8 to 10, wherein part or all of the inner surface of the through-hole is an inclined surface in a cross-sectional view.

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