JP7111993B2 - Method for manufacturing light-emitting module - Google Patents

Description

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

TECHNICAL FIELD The present disclosure relates to light emitting modules and methods of manufacturing light emitting modules.

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 light-emitting module that can be made thinner.

The present disclosure includes the following configurations.
a step of preparing a plurality of light sources each having a semiconductor laminate and an electrode;
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 light adjustment members in the through-holes;
disposing bonding members on the light adjusting members;
aligning the heights of the upper surfaces of the plurality of joining members;
placing the light sources on the bonding member with the electrodes facing upward;
arranging a covering member covering the second main surface;
A method of manufacturing a light-emitting module, comprising the step of forming a wiring layer electrically connected to the light source.

A thin light-emitting module can be provided.

1 is a configuration diagram 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. 1A and 1B are a schematic plan view and a schematic cross-sectional view showing an example of a light-emitting module according to an 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; 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; 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 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. Schematic showing an example of a manufacturing process of a light-emitting module according to an embodiment 1 is a schematic cross-sectional view showing an example of a light emitting module according to an embodiment; FIG. It is a plan view. 1A and 1B are a schematic plan view and a schematic cross-sectional view showing an example of a light guide plate of a light emitting module according to an embodiment; 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. 1A and 1B are a schematic plan view and a schematic cross-sectional view showing an example of a light source according to an 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. 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;

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. In addition, the contents described in one embodiment and example can also be applied to other embodiments and examples. Also, the sizes and positional relationships of members shown in the drawings may be exaggerated for clarity of explanation.

<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, members such as a polarizing film, a color filter, and a DBEF may be further provided.

<Surface light source>
The planar light source 1400 includes at least one light emitting module and at least one wiring board. Depending on the size of the liquid crystal panel 1100, the planar light source 1400, etc., the number, size, arrangement, etc. of the light emitting modules and wiring boards can be selected.

<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. Also, the light emitting module 100 shown in FIG. 2B is an example of a light emitting module 100 smaller in size than the planar light source 1400 , and one planar light source 1400 includes a plurality of light emitting modules 100 . Hereinafter, the light emitting module 100 shown in FIG. 2B will be described as an example.

3A and 3B show an example of a light emitting module 100 according to an embodiment. The light emitting module 100 includes a light guide plate 10 and a plurality of light sources 20 joined to the light guide plate 10 . The light source 20 has a first surface 20a including an electrode 23 and a second surface 20b opposite the first surface 20a. The light source 20 may use only a light emitting element as a light source, or may use a light emitting device including a light emitting element and other members as a light source. The light guide plate 10 includes a first principal surface 11 , a second principal surface 12 opposite to the first principal surface 11 , and a through hole 13 penetrating from the first principal surface 11 to the second principal surface 12 .

A light adjusting member 50 is arranged in the through hole 13 . The light adjusting member 50 and the light source 20 are joined together by a joining member 30 .

Such a light-emitting module can be obtained by a manufacturing method comprising the following steps.
A method for manufacturing a light-emitting module includes:
(1) preparing a plurality of light sources each having a semiconductor laminate and an electrode;
(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 members in the through-holes;
(4) arranging each bonding member on the light adjusting member;
(5) aligning the heights of the upper surfaces of the plurality of joining members;
(6) placing light sources on the bonding members with the electrodes facing upward;
(7) arranging a covering member covering the second main surface;
(8) forming a wiring layer electrically connected to the light source;
Prepare.

The light-emitting module according to the present disclosure can reduce variations in the height of the light source by aligning the heights of the joining members.

(Embodiment 1)
A method for manufacturing the light-emitting module according to the first embodiment will be described in detail.

(1) Step of preparing a plurality of light sources each having a semiconductor laminate and electrodes A plurality of light sources are prepared. The light source 20 that can be used in the manufacturing method according to the embodiment includes, for example, light sources 20A to 20F shown in FIGS. 14A to 14F. is mentioned. Such a light source 20 comprises a first surface (upper surface) 20a having electrodes 23 and a second surface (upper surface) 20b opposite to the first surface 20a. When the light emitting device is used as the light source 20, the light emitting element 21 and other members are combined, for example, by performing some or all of the steps of forming the coating member 26, the translucent member 24, and the like, which will be described later. can do. Alternatively, the light source 20 can be prepared by purchase. In the following description, each step of the manufacturing method of the light emitting module 100 using the light emitting element 21 as the light source 20 will be described.

(2) Step of Preparing a Light Guide Plate Having a First Principal Surface to Become a Light Emitting Surface and a Second Principal Surface Opposite to the First Principal Surface As shown in FIG. 4A, a 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 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 recesses 14 described later, and the like can be collectively formed with a mold 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 preparing a translucent plate that does not have the through holes 13 and the concave portions 14 and processing the plate. Alternatively, the light guide plate 10 having the through holes 13 and the recesses 14 may be purchased and prepared.

(3) Step of Arranging Light Adjustment Members in Through Holes The light adjustment members 50 are arranged in the through holes 13 . The light adjustment member 50 includes a light reflective member. The light adjustment member 50 can fill the entire through hole 13 . For example, as shown in FIG. 4B, the light guide plate 10 is placed on a workbench or the like with the first main surface 11 facing downward and the second main surface 12 facing upward. Then, the liquid light adjustment member 50 is placed inside the through-hole 13 from the opening of the through-hole 13 on the second main surface 12 side. Here, the term "liquid" refers to a fluid state such as paste or gel. When the liquid bonding member 30 is used, it can be formed by a transfer molding method, a compression molding method, a potting method, a transfer method, a printing method, a jet dispensing method, or the like. In the example shown in FIG. 4B , the light adjusting member 50 is arranged inside the through-hole 13 by a printing method using a squeegee 70 . Alternatively, the preformed light adjustment member 50 may be prepared and arranged in the through hole 13 . At this time, depending on the size of the light adjustment member 50, the light adjustment member 50 may be pushed into the through hole 13 by pressing.

(4) Step of Disposing Bonding Members on Light Adjustment Members Next, liquid bonding members 30 are disposed on the light adjustment members 50, respectively, as shown in FIG. 4C. The joining member 30 can be arranged by a method such as potting, transfer, or printing. FIG. 4C illustrates a case where the bonding member 30 is arranged by potting using the dispensing nozzle 71 . As shown in FIG. 4D, the upper surface of the joining member 30 arranged on the light adjusting member 50 is convexly curved.

(5) Step of Equalizing Top Surfaces of Plurality of Bonding Members Next, as shown in FIG. Here, the bonding member 30 is ground using a grinding member 72 such as a whetstone. Thereby, as shown in FIG. 4F, the heights of the upper surfaces of the joining members 30 are made uniform. The “height” here does not refer to the thickness of the joint member 30 , but refers to the position of the upper surface of the joint member 30 . Moreover, as a method for aligning the heights of the joint members 30, there is a method of pressing the joint members 30. As shown in FIG.

(6) Step of Placing the Light Sources on the Joining Members with the Electrodes Up Next, as shown in FIG. 4G, the light sources 20 are placed on the upper surfaces of the joining members 30 . At this time, the light source 20 is placed with the electrode 23 (first surface 20a) facing upward. That is, the second surface 20 b of the light source 20 is placed so as to face the upper surface of the bonding member 30 . After that, the bonding member 30 is cured to bond the light source 20 and the light adjustment member 50 together.

(7) Step of Arranging Light Reflective Member Covering Second Principal Surface Next, as shown in FIG. 4H, a light reflective member 40 is formed so as to cover the second principal surface 12 of the light guide plate 10 . At this time, the light reflecting member 40 is formed thick so as to cover the electrode 23 (first surface 20a) of the light source 20 as well. The light-reflecting member 40 can be formed, for example, by forming a liquid light-reflecting member 40 by transfer molding, compression molding, potting, printing, spraying, or the like, followed by curing.

Next, as shown in FIG. 4I, part of the light reflecting member 40 is removed to expose the electrodes 23 of the light source 20 . Methods for removing include grinding using a grinding member such as a whetstone, blasting, and the like. Since the heights of the joining members 30 are uniform, all the electrodes 23 of the plurality of light sources 20 can be exposed in the same step.
When the light reflecting member 40 is formed, it is formed so that the first surface 20b of the light source 20 is exposed. In particular, the light reflecting member 40 is formed so that the electrodes 23 are exposed.

(8) Step of forming a wiring layer for electrically connecting a plurality of light emitting elements Next, as shown in FIG. to form As the wiring layer 60, for example, Ag, Ag/Cu, Ni/Au, or the like can be used. The wiring layer 60 may use these materials alone, or may be an alloy containing a plurality of materials, or may have a laminated structure. Examples of the method of forming the wiring layer 60 include sputtering, plating, printing, bonding of metal foil, and the like.

The wiring layer 60 can be formed in a predetermined pattern by using a mask or the like. Also, the wiring layer 60 is formed on the entire surface including the electrodes 23 of the light source 20 and the light reflecting member 40, and then the wiring layer 60 is partially removed to form the wiring layer 60 with a predetermined pattern. be able to. Methods for partially removing the wiring layer include etching and laser light irradiation.
As described above, the light-emitting module 100 of this embodiment can be obtained.

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. In the example shown in FIG. 3A and the like, 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 board 200 can be adhered using an adhesive sheet or the like. Thereby, a planar light source 1400 as shown in FIG. 5 can be obtained. The wiring of the wiring board 200 is electrically connected to the external terminals 61 and 62 of the wiring layer 60 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-shaped adhesive sheet can be placed between the surface of the light-reflective 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 pressing them together. . 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 the via hole, can be melted by applying pressure and heat and joined to the metal film.

(Embodiment 2)
FIG. 6 is an example of a light emitting module according to the second embodiment. In the light emitting module 100A, the light adjusting member 50 is arranged on the first main surface 11 side in the through hole 13 of the light guide plate 10, and the translucent member 42 (second translucent member) is arranged on the second main surface 12 side. member) are placed. A member that transmits 90% or more of the light from the light source 20 is used as the translucent member 42 . Translucent member 42 may include a wavelength converting material such as a phosphor that absorbs light from light source 20 and converts it into light of a different wavelength.

Such a method for manufacturing the light emitting module 100A can be the same as the first embodiment except for the steps including the step of arranging the light adjusting member 50 and the step of arranging the translucent member 42 .

As for the method of arranging the light adjustment member 50 , for example, the light adjustment member 50 can be arranged in the through hole 13 by preparing a pre-shaped light adjustment member 50 . For example, as shown in FIG. 7A, the width (diameter) of the light adjustment member 50 is equal to or smaller than the width (opening diameter) of the through hole 13. , into the through hole 13 . 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 molded light adjustment 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 height of the light adjustment member 50 is smaller than the depth of the through hole 13 . For example, the height of the light adjusting member 50 can be 10% to 90% of the depth of the through-hole 13 . By arranging the light adjustment member 50 whose depth is smaller than the depth of the through hole 13 in this manner, a recess is formed having the second surface 52 of the light adjustment member 50 as the bottom surface and the inner surface 131 of the through hole 13 as the side surface. will be

The first surface 51 or the second surface 52 of the light adjustment member 50 can be flat or curved. 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 adjusting member 50 and the inner surface 131 of the through hole 13 , the light adjusting member 50 and the light guide plate 10 can be fixed.

The method of forming the light adjustment member 50 includes, for example, a method of separating the plate-like or sheet-like light adjustment member 50 having a large area into individual pieces by cutting, punching, or the like. Alternatively, it is possible to form a molded product of the small piece of the light adjustment member 50 by a method such as injection molding, transfer molding, or compression molding using a mold or the like.

Next, as shown in FIG. 7B, the translucent member 42 is arranged on the light adjusting member 50 inside the through hole 13 . The translucent member 42 can be arranged by transfer molding, compression molding, potting, transfer, printing, jet dispensing, or the like. In the example shown in FIG. 7B, the translucent member 42 is arranged by a printing method using a squeegee 70 . Alternatively, a preformed translucent member 42 may be prepared and placed in the through hole 13 . After that, by performing the same steps as in Embodiment 1, the light-emitting module 100A shown in FIG. 6 can be obtained.

FIG. 8 is an example of a modification of the light emitting module. In the light guide plate 10 of the light emitting module 100B, a part of the inner side surface 131 of the through hole 13 is an inclined surface in cross-sectional view. Specifically, an inner side 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 through hole 13 may be an inclined surface. Also, instead of the inclined surface, a step may be provided.

The side surfaces of the molded light adjustment member 50 can also be inclined surfaces. The side surface of the light adjusting member 50 can be an inclined surface having the same angle as the inclined surface of the inner side surface 131 of the through hole 13 .

When the width (diameter) of the molded light adjustment member 50 is the same as the width (diameter) of the opening of the through hole 13 on the second main surface 12 side, the first main surface 11 of the light guide plate 10 and the light adjustment member The first surface 51 of 50 can be the same surface.

When the width (diameter) of the light adjustment member 50 is smaller than the width (diameter) of the opening of the through hole 13 on the second main surface 12 side, as shown in FIG. A first surface 51 of the light adjusting member 50 is located at a position lower than 11 . In other words, part of the inner surface 131 of the through hole 13 is in contact with the air layer. Thereby, the light extraction efficiency can be improved by reflecting the light with the air layer.

As shown in FIG. 9, a through hole 13 having an opening diameter on the side of the first main surface 11 of the light guide plate 10 smaller than that on the side of the second main surface 12 is placed with the first main surface 11 facing downward. do. Then, the light adjusting member 50 having the width (diameter) of the first surface 51 larger than the width (aperture diameter) of the first main surface 11 is placed on the second surface of the light guide plate 10 with the first surface 51 facing downward. It is inserted into the through hole 13 from the opening on the main surface 12 side. Thereby, the light adjusting member 50 can be fixed in the through hole 13 without using an adhesive.

FIG. 10 is an example of a modification of the light emitting module. The second surface 52 of the light adjustment member 50 of the light emitting module 100C is convex. For example, as shown in FIG. 11, such a light adjustment member 50 is supplied by using a dispensing nozzle 71 to supply the liquid light adjustment member 50 into the through-hole 13, and the upper surface (second surface 52) is displaced by surface tension. It can be formed by making it convex and hardening it in this state. Thereby, as shown in FIG. 10 , the light adjustment member 50 that is convex toward the light source 20 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 efficiently spread in the horizontal direction.

FIG. 12 is an example of a modification of the light emitting module. 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.

13 is a cross-sectional view of the light guide plate 10 used in the light emitting module 100D shown in FIG. 12. FIG. Such a light guide plate 10 is prepared, and the liquid light adjustment member 50 is poured into the through hole 13 from the opening on the second main surface 12 side using the dispensing nozzle 71 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.

Further, the light guide plate 10 shown in FIG. 13 has a concave portion 14 on the second main surface 12 side. The concave portion 14 is arranged between the through holes 13 adjacent to each other in a cross-sectional view. The recessed portion 14 is annularly arranged so as to surround the through hole 13 in plan view. A part of the light reflecting member 40 can be placed in the recess 14 as shown in FIG. Thereby, the light from the light source 20 can be easily reflected toward the first main surface 11 side.

(Embodiment 3)
FIG. 15 is an example of a light emitting module according to the third embodiment. In the light-emitting module 100E, in the through hole 13 of the light guide plate 10, the light adjustment member 50 is arranged on the first main surface 11 side, and the translucent member 42 is arranged on the second main surface 12 side. , which are the same as those of the second embodiment. In Embodiment 3, the translucent member 42 is positioned above the opening of the through hole 13 . In the example shown in FIG. 15 , the translucent member 42 is arranged extending from the through hole 13 onto the second main surface 12 .

In the method of forming such a translucent member 42, first, as shown in FIG. . At this time, the upper surface of the translucent member 42 is formed so as to be higher than the second main surface 12 . After that, as shown in FIG. 16B, the height of the translucent member 42 is made uniform by the grinding member 72 . By arranging the heights of the translucent members 42, grinding of the light guide plate 10 itself can be suppressed. If the light guide plate 10 has minute unevenness such as grinding marks, the light will be diffused at that portion, and the light transmission efficiency will easily decrease. Therefore, by grinding the translucent member 42, it is possible to reduce light loss due to grinding marks. It should be noted that the height of the translucent member 42 may be adjusted by pressing.

The steps other than the step of aligning the height of the translucent member 42 can be performed in the same manner as in the second embodiment. In Embodiment 3, the joining member 30 can be arranged on the translucent members 42 having the same height, as shown in the left side view of FIG. 16C. At this time, the step of aligning the heights of the arranged joining members may be performed, or may be omitted.

Alternatively, as shown in the right side view of FIG. 16C, the wavelength converting member 43 may be arranged on the translucent member 42, and the bonding member 30 may be arranged thereon. As the wavelength conversion member 43, a preformed sheet-like or block-like member can be used. Alternatively, it may be formed by a method such as potting, transfer, or printing.

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

(Light guide plate)
When the light guide plate 10 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. Also, the thickness of the light guide plate 10 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 main surface 11 or the second main surface 12, for example. . For example, as shown in FIG. 4B , the thickness H between the first main surface 11 and the second main surface 12 around the through hole 13 is the thickness of the light guide plate 10 . The plan view shape of the light guide plate 10 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 obtained by combining these, a shape partially rounded, a shape partially missing, or the like can be used.

As materials for the light guide plate 10, thermoplastic resins such as acrylic, polycarbonate, cyclic polyolefin, polyethylene terephthalate, and polyester, resin materials such as thermosetting resins such as epoxy and silicone, and optically transparent materials such as glass are 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 10 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.

(through hole)
The through hole 13 penetrates from the first main surface 11 to the second main surface 12 of the light guide plate 10, and is a portion in which the light source 20 is arranged.

The plurality of through holes 13 are arranged two-dimensionally in a plan view of the light guide plate 10 . Preferably, the plurality of through-holes 13 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 and 2B, the arrangement pitch of the through-holes 13 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 13 may be arranged so that the distance between them increases from the center to the periphery of the light guide plate 10 .

The opening of the through-hole 13 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.

(Recess: Reflector)
The light guide plate 10 may have a flat surface on the second main surface 12 except for the through holes 13 . The side surface of the concave portion 14 can function as a reflector that reflects the light from the light source 20 arranged in the through hole 13 toward the first main surface 11 side. Therefore, it is preferable that the concave portion 14 is arranged for each through-hole 13 in which the light source 20 is arranged when viewed from above.

The side surface of the concave portion 14 can be straight or curved in a cross-sectional view, or a combination thereof. Further, when the side surface of the recess 14 is curved, the curvature may be constant, or may have an arbitrary curvature depending on the position.

(light source)
Figures 14A-14F illustrate a light source 20 that can be used in a light emitting module according to embodiments. Each light source 20 has a first surface (lower surface) 20a with electrodes 23 and a second surface (upper surface) 20b opposite to the first surface 20a.

A light emitting element 21 can be used as the light source 20 . Alternatively, the light source 20 can use a light-emitting device including the light-emitting element 21 and a member covering the light-emitting element 21 .

A light source 20A shown in FIG. 14A is composed only of the light emitting element 21 . The light emitting element 21 includes a semiconductor laminate 22 and a pair of electrodes 23 provided on the lower surface thereof. The first surface 20a of the light source 20A is the first surface 21a of the light emitting element 21 . A second surface 20b of the light source 20A is the top surface of the light emitting element 21 . A side surface of the light source 20A is a side surface of the light emitting element 21 .

As the light emitting element 21, a known semiconductor light emitting element such as a light emitting diode can be used. The composition, emission wavelength, size, number, etc. of the semiconductor laminate 22 of the light emitting element 21 to be used can be appropriately selected according to the purpose. As the light emitting element 21, a light emitting element that emits light of any wavelength from ultraviolet light to visible light can be selected. For example, as a light-emitting element that emits ultraviolet, blue, and green light, the semiconductor laminate 22 may be a nitride-based semiconductor (In _x Al _y Ga _1-xy N, 0≦X, 0≦Y, X+Y≦ A light-emitting element using 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 22 and its crystallinity. The shape of the semiconductor laminate 22 of the light emitting element 21 can be a quadrangle such as a square or rectangle, or a polygon such as a triangle or hexagon in a 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 21 can be set to, for example, 5 μm to 300 μm. As the electrode 23 of the light emitting element 21, for example, Cu, Au, Ni, or the like can be used. The thickness of the electrode 23 can be, for example, 0.5 μm to 100 μm.

The light sources 20B and 20C shown in FIGS. 14B and 14C are light emitting devices in which the side and top surfaces of the semiconductor laminate 22 of the light emitting element 21 are covered with a translucent member (first translucent member) 24. The light-transmitting member 24 constitutes a part of the side surface of the light source on the side of the light-emitting element 21, so that the light emitted from the side of the light-emitting element 21 is transmitted to the side of the light source. can be easily emitted toward the By arranging at least part of the translucent member 24 of the light source having such a structure inside the through hole 13 , light can enter the light guide plate 10 from the inner surface of the through hole 13 .

The translucent member 24 may be a single layer or a laminated structure including multiple layers. When the translucent member 24 has a laminated structure, for example, it can be a combination of a layer containing a wavelength converting substance such as a phosphor and a layer not containing the wavelength converting substance. Alternatively, there can be multiple layers containing different wavelength converting materials.

In the light source 20</b>B, the lower surface of the semiconductor laminate 22 of the light emitting element 21 and the electrode 23 are exposed from the translucent member 24 . In such a case, it is preferable to reduce the thickness of the electrode 23 of the light emitting element 21 . The thickness of the electrode 23 can be, for example, about 0.5 μm to 100 μm. With such a structure, the thickness of the light source can be reduced. Therefore, the light emitting module can be made thin.

The light source 20</b>C includes a light-reflective covering member 26 that covers the lower surface of the semiconductor laminate 22 of the light emitting element 21 and the side surface of the electrode 23 . That is, the first surface 20 a of the light source is composed of the covering member 26 and the electrodes 23 of the light emitting elements 21 . Thereby, it is possible to prevent the light from the light emitting element 21 from being absorbed by the wiring board or the like.

Light sources 20D to 20F shown in FIGS. 14D to 14F are light emitting devices in which a light reflecting covering member 26 is arranged on the side of the light emitting element 21. FIG. By using the light source having such a structure, it is possible to make it easier for the light from the light emitting element 21 to enter the light adjustment member 50 . In addition, when the translucent member 24 contains a wavelength converting substance, by arranging the light-reflective coating member 26 on the side of the light emitting element 21, only the light from the light emitting element 21 enters the light adjusting member 50. Injection can be suppressed. In other words, the mixed light of the light from the light emitting element 21 and the light from the wavelength conversion material can enter the light adjustment member 50, and color unevenness can be reduced.

The covering member 26 directly or indirectly covers the side surface of the semiconductor laminate 22 of the light emitting element 21 . In the light sources 20D and 20E, the covering member 26 covers the side surface of the semiconductor laminate 22 of the light emitting element 21 via the translucent adhesive member 25 covering the side surface of the semiconductor laminate 22 of the light emitting element 21. FIG. However, without being limited to this, the covering member 26 may be in contact with the side surface of the semiconductor laminate 22 of the light emitting element 21 as in the light source 20F.

In the light source 20E, the covering member 26 covers the side surface of the translucent member 24. As shown in FIG. With such a structure, light can efficiently enter the light adjustment member 50 located on the upper surface of the translucent member 24 . In addition, when the translucent member 24 contains a wavelength converting substance, by arranging a light-reflective coating member 26 on the side of the translucent member 24, only the light from the light-emitting element 21 can be transmitted to the light adjusting member 50. It is possible to efficiently suppress the incident on the inside. That is, the mixed light of the light from the light emitting element 21 and the light from the wavelength conversion material can be efficiently incident on the light adjustment member 50, and color unevenness can be reduced.

The light sources 20</b>D and 20</b>E are bonded to the translucent member 24 and the light emitting element 21 with a translucent adhesive member 25 . The translucent adhesive member 25 covers the side surface of the semiconductor laminate 22 of the light emitting element 21 . The translucent adhesive member 25 may be between the light emitting element 21 and the translucent member 24 . Also, the translucent adhesive member 25 may be omitted as shown in the light source 20F. As the translucent adhesive member 25, an epoxy resin, a silicone resin, a resin mixture thereof, or the like can be used.

The light source 20F includes multiple light emitting elements 21 . Here, an example in which four light emitting elements 21 are arranged in two columns and two rows is shown. The number of light emitting elements 21 is not limited to this. The emission wavelengths of the light emitting elements 21 may be the same or different. For example, in the upper diagram of FIG. 14F, red light emitting elements and green light emitting elements can be arranged from the left in the upper row, and blue light emitting elements and red light emitting elements can be arranged from the left in the lower row. When light-emitting elements of three primary colors of light are provided as described above, the translucent member 24 placed thereon does not need to be provided with a wavelength converting substance.

The light source in which the bottom surface of the semiconductor laminate 22 of the light emitting element 21 and the side surface of the electrode 23 are covered with the covering member 26 or the translucent member 24 may include a metal film such as a plating layer or a sputter film that covers the electrode 23. . 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 the electrode 23 and the covering member 26 covering the side surfaces of the pair of electrodes 23 or part of the translucent member 24 .

(translucent member)
The light-transmitting material 24 has a light-transmitting property that allows at least the light from the light-emitting element 21 to pass therethrough, and transmits 60% or more, preferably 90% or more of the light emitted from the light-emitting element 21 . As a material for the translucent member 24, translucent thermosetting resin materials such as epoxy resin and silicone resin can be used.

The translucent member 24 may contain particulate phosphor as a wavelength conversion substance in the above resin material. The wavelength conversion substance includes a wavelength conversion substance such as phosphor that converts the wavelength of light emitted from the light emitting element 21 into light of a different wavelength. The translucent member 24 may include a single layer or multiple 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 (eg, Y ₃ (Al, Ga) ₅ O ₁₂ :Ce), lutetium-aluminum-garnet-based phosphors (eg, Lu ₃ (Al, Ga) ₅ O ₁₂ :Ce), terbium-aluminum-garnet-based phosphors (e.g. Tb3 ₍ Al, Ga) _5O12 :Ce)-based phosphors, silicate _- based phosphors (e.g. ₍ Ba, Sr) _2SiO4 :Eu), Chlorosilicate-based phosphors (for example, Ca ₈ Mg(SiO ₄ ) ₄ Cl ₂ :Eu) can be mentioned. Furthermore, as nitride phosphors, β-sialon phosphors (eg Si _6-z Al _z O _z N _8-z :Eu (0<z<4.2)), α-sialon phosphors (eg Mz ( Si, Al) ₁₂ (O, N) ₁₆ (where 0 < z ≤ 2, and M is a lanthanide element excluding Li, Mg, Ca, Y, and La and Ce), nitrogen-containing calcium aluminosilicate (CASN or SCASN)-based phosphors (for example, (Sr, Ca)AlSiN ₃ :Eu), etc. Phosphors represented by the general formula (I) _{MaxMbyAl 3} N _{z :} Eu (provided that the general formula ( In I)), Ma is at least one element selected from the group consisting of Ca, Sr and Ba, and Mb is at least one element selected from the group consisting of Li, Na and K. , x, y, and z respectively satisfy 0.5≦x≦1.5, 0.5≦y≦1.2, and 3.5≦z≦4.5). Furthermore, an SGS-based phosphor (for example, SrGa ₂ S ₄ :Eu) can be used. In addition, a manganese-activated fluoride-based phosphor (a phosphor represented by the general formula (II) A ₂ [M _{1-a Mna} F ₆ ] (provided that in the above general formula (II), A is K, At least one element selected from the group consisting of Li, Na, Rb, Cs and NH4, M is at least one element selected from the group consisting of Group 4 elements and Group 14 elements, and a is 0 satisfying <a<0.2)). A representative example of this manganese-activated fluoride-based phosphor is a manganese-activated potassium fluorosilicate phosphor (for example, KSF (K ₂ SiF ₆ :Mn)).

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, the light emitting element 21 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. can. By using such two types 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 24 . For example, the phosphor may be distributed substantially uniformly inside the wavelength conversion member, or may be unevenly distributed.

The translucent member 24 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.

The light-transmitting member (second light-transmitting member) 42 arranged in the through-hole 13 is the same as the light-transmitting member (first light-transmitting member) 24 used in the light source 20 described above. can be done. The first translucent member 24 and the second translucent member 42 may be the same or different. Alternatively, the first translucent member 24 may contain the wavelength converting substance, and the second translucent member 42 may not substantially contain the wavelength converting substance. Conversely, the second translucent member 42 may contain the wavelength converting substance, and the first translucent member 24 may not substantially contain the wavelength converting substance.

(coating member)
The covering member 26 is a light reflecting member. The coating member 26 may have a reflectance of, for example, 60% or more, preferably 70% or more, and more preferably 90% or more, with respect to the light emitted from the light emitting element 21 . The material of the covering member 26 is preferably a resin material containing a white pigment or the like. In particular, a silicone resin containing titanium oxide is preferred.

(joining member)
The joining member 30 is a translucent member that joins the light source 20 and the light guide plate 10 together.

As a material of the joining member 30, an epoxy resin, a silicone resin, a mixed resin of these, or a translucent material such as glass can be used.

(Light reflective member)
The light reflective member 40 is a light reflective member that covers the plurality of light sources 20 and the second main surface 12 of the light guide plate 10 . By covering the entire second main surface 12 with the light reflecting member 40 , the light from the light source 20 can be efficiently introduced into the light guide plate 10 .

The light reflecting member 40 has a reflectance of 60% or more, preferably 90% or more, with respect to the light emitted from the light source 20 . The material of the light reflecting member 40 can be, for example, metal, white resin material, DBR film, or the like. A white resin material is particularly preferable for the material of the light reflecting member 40 . 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)
Preferably, the light adjusting member 50 is arranged in the through hole 13 of the light guide plate 10 and has a function of reflecting part of the light from the light source 20 . For example, it has a reflectance of 70% to 90%, preferably 80% to 85%, with respect to the light emitted from the light source 20 . 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.

(Wavelength conversion member)
The wavelength conversion member 43 is a member arranged on the translucent member (second translucent member) 42 in the through hole 13, and is arranged on the translucent member (the first translucent member 24, the second translucent member 24, the second translucent member). It is possible to contain the wavelength converting substance mentioned in the property member 42).

(wiring board)
The wiring board 200 includes an insulating base material 210 and wiring 220 . The wiring is electrically connected to the multiple light sources 20 .

The wiring board 200 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 sides of the base material. .

The wiring board 200 may have a laminated structure. For example, as the wiring board 200, a metal plate having an insulating layer on its surface may be used. Also, the wiring substrate 200 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 base material and electrically connected to the plurality of light sources 20 . The wiring material preferably has high thermal conductivity. Such materials include, for example, conductive materials such as copper. Moreover, 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, 100A, 100B, 100C, 100D, 100E... 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 14... Recessed part 20... Light-emitting device (light source)
20a: first surface (electrode forming surface of light source)
20b...Second surface (upper surface of light source)
20c... Side surface of light source 21... Light emitting element (light source)
DESCRIPTION OF SYMBOLS 22... Semiconductor laminated body 23... Electrode 24... Translucent member (1st translucent member/translucent member of light source)
241 First translucent member 242 Second translucent member 25 Translucent adhesive member 26 Covering member 30 Joining member 40 Light reflecting member 42 Translucent member (second translucent member / Translucent member in through-hole)
43... Wavelength conversion member 50... Light adjustment member 51... First surface of light adjustment member (first main surface side of light guide plate)
52 . . . Second surface of light adjustment member (second principal surface side of light guide plate)
DESCRIPTION OF SYMBOLS 60... Wiring layer 61, 62... External terminal 70... Squeegee 71... Dispensing nozzle 72... Grinding member

Claims (8)

a step of preparing a plurality of light sources each having a semiconductor laminate and an electrode;
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 light adjustment members in the through-holes;
disposing bonding members on the light adjusting members;
aligning the heights of the upper surfaces of the plurality of joining members;
placing the light sources on the bonding member with the electrodes facing upward;
arranging a covering member covering the second main surface;
forming a wiring layer electrically connected to the light source;
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 aligning the height of the upper surface of said joining member includes a step of aligning the height by grinding. 2. The method of manufacturing a light-emitting module according to claim 1, wherein the step of aligning the height of the upper surface of said joining member includes a step of aligning the height by pressing. 4. The step of placing the joining member includes forming a translucent member on the light adjusting member and arranging the joining member on the translucent member. 2. A method for manufacturing the light-emitting module according to item 1. a step of preparing a plurality of light sources each having a semiconductor laminate and an electrode;
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 light adjustment members in the through-holes;
disposing, on the light adjustment member, translucent members each having an upper surface at a position higher than at least the second main surface;
aligning the heights of the upper surfaces of the plurality of translucent members;
placing the light sources on the bonding members with the electrodes facing upward;
arranging a covering member covering the second main surface;
forming a wiring layer electrically connected to the light source;
A method of manufacturing a light-emitting module comprising: 6. The method of manufacturing a light-emitting module according to claim 5, wherein the step of aligning the height of the upper surface of the translucent member includes a step of aligning the height by grinding. 6. The method of manufacturing a light-emitting module according to claim 5, wherein the step of aligning the height of the upper surface of the translucent member includes a step of aligning the height by pressing. 8. The method of manufacturing a light-emitting module according to claim 5, wherein the step of placing the light source includes the step of placing a bonding member on the translucent member.

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