JP6879325B2 - Light emitting module manufacturing method and light emitting module - Google Patents

Description

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

A light emitting device using a light emitting element such as a light emitting diode is widely used as a backlight of a liquid crystal display or various light sources such as a display.
For example, the light source device disclosed in Patent Document 1 is composed of a plurality of light emitting elements mounted on a mounting substrate, a hemispherical lens member that seals each of the plurality of light emitting elements, and a light emitting element arranged on the hemispherical lens member. It is provided with a diffusion member into which the light of the above is incident.
Further, in the light emitting device disclosed in Patent Document 2, a two-layer sheet in which a sealing resin layer and a phosphor layer are integrated is fixed to the upper surface of a light emitting element, and the side surface thereof is covered with a reflective resin.

JP-A-2015-323373 Japanese Unexamined Patent Publication No. 2016-115703

However, in a light source device such as Patent Document 1, it is necessary to make the distance between the mounting substrate and the diffuser plate larger than the thickness of the lens member, and there is a possibility that sufficient thinning cannot be achieved. Further, the light emitting device of Patent Document 2 cannot uniformly disperse and irradiate light from a plurality of light emitting elements, and cannot be used in applications that require light emitting characteristics with less uneven brightness.

Therefore, an object of the present invention is to provide a method for manufacturing a light emitting module and a light emitting module capable of realizing a light emitting characteristic that is thin, uniform, and has little luminance unevenness.

The method for manufacturing a light emitting module according to the present invention comprises a light guide plate provided with a first main surface serving as a light emitting surface and a second main surface provided with a recess on the side opposite to the first main surface, and a phosphor. A method for manufacturing a light emitting module including a light adjusting unit including a light adjusting unit and a light emitting element bonded to the light adjusting unit. A light emitting element unit in which a light guide plate, a light adjusting unit, and a light emitting element are joined to form an integral structure. The inner circumference and insertion of the recess can be made by fixing the light adjustment part of the light emitting element unit to the recess and arranging the insertion part including the light adjustment part in the recess, which has a smaller outer shape than the inner shape of the recess. A bonding agent is filled in the ring gap formed between the outer periphery of the portion to form a bonding wall, the volume of the ring gap is made larger than the volume of the insertion portion of the light emitting element unit, and wiring is provided to the electrode of the light emitting element. Form to manufacture a light emitting module.

Further, the light emitting module according to the present invention has a translucent light guide plate provided with a recess on the second main surface opposite to the first main surface which is a light emitting surface that radiates light to the outside, and a recess of the light guide plate. The light emitting element unit is provided with a light emitting element unit fixed to the light emitting element, and the light emitting element unit has a light adjusting portion containing a phosphor bonded to the light emitting element. A translucent bonding agent that is smaller than the inner shape of the recess and is filled in the ring gap between the insertion portion and the recess is provided as a joint wall, and the volume of the ring gap is the volume of the insertion portion of the light emitting element unit. Larger than volume .

The method for manufacturing a light emitting module according to the present invention can provide a light emitting module including a light guide plate and a light emitting element that reduce brightness unevenness and realize uniform light emitting characteristics while reducing the overall thickness. This is because the light emitting element unit in which the light adjusting portion is fixed to the recess of the light guide plate and the light emitting element is bonded to the light adjusting portion is arranged at a fixed position of the light guide plate. Further, in the above manufacturing method, a light emitting element unit having an integrated structure of a light adjusting unit containing a phosphor and a light emitting element is formed, and the light adjusting unit of the light emitting element unit is fixed to a recess of a light guide plate to form a light emitting element unit. Is placed at a fixed position on the light guide plate, eliminating the relative misalignment between the light adjustment unit, the light emitting element, and the recess of the light guide plate, and fixing to the correct position with extremely high accuracy, making the whole thinner. However, it can be efficiently mass-produced and has the feature of reducing uneven brightness on the surface of the light guide plate.

Further, in the light emitting module according to the present invention, a light emitting element unit in which a light adjusting portion containing a phosphor is bonded to the light emitting surface of the light emitting element is fixed to the recess of the light guide plate, and the light emitting module is arranged in the recess of the light emitting element unit. The outer shape of the insertion part to be inserted is made smaller than the inner shape of the recess of the light guide plate, and the translucent bonding agent filled in the ring gap between the insertion part and the recess is used as the joint wall. It has the feature of being able to realize uniform light emission characteristics with little uneven brightness while making it thinner. It emits light at the exact position of the recess of the light guide plate by arranging the insertion part of the light emitting element unit in the recess of the light guide plate and providing a translucent joint wall between the insertion portion of the light emitting element unit and the recess. This is because the element unit is arranged so that the light emitted from the light emitting element can be incident on the light guide plate via the light adjustment unit, diffused by the light guide plate, and radiated to the outside.

It is a block diagram which shows each structure of the liquid crystal display device which concerns on embodiment. It is a schematic plan view of the light emitting module which concerns on one Embodiment. It is a partially enlarged schematic cross-sectional view of the light emitting module which concerns on one Embodiment, and is the figure which turned upside down with the light guide plate down. It is a schematic bottom view of the light emitting module which concerns on another embodiment. It is a schematic bottom view which shows the state which arranges the quadrangular insertion part in an inclined posture with respect to the quadrangular recess. It is a schematic bottom view which shows the state which arranges the quadrangular insertion part in a parallel posture with respect to the quadrangular recess. It is sectional drawing which shows the state which the surface level of a joint wall becomes low due to the error of the filling amount of a bonding agent. It is sectional drawing which shows the state which the surface level of a joint wall becomes high by the error of the filling amount of a bonding agent. 9A-9D are enlarged schematic cross-sectional views showing an example of a manufacturing process of the light emitting unit according to the embodiment. 10A to 10D are enlarged schematic cross-sectional views showing an example of a manufacturing process of the light emitting unit according to the embodiment. 11A to 11C are enlarged schematic cross-sectional views showing an example of a manufacturing process of the light emitting module according to the embodiment. 12A to 12C are enlarged schematic cross-sectional views showing an example of a manufacturing process of the light emitting module according to the embodiment. FIG. 3 is an enlarged schematic cross-sectional view showing an example of connecting a circuit board to the light emitting module shown in FIG.

Hereinafter, the present invention will be described in detail with reference to the drawings. In the following description, terms indicating a specific direction or position (for example, "upper", "lower", and other terms including those terms) are used as necessary, but the use of these terms is used. This is for facilitating the understanding of the invention with reference to the drawings, and the meaning of these terms does not limit the technical scope of the present invention. Further, the parts having the same reference numerals appearing in a plurality of drawings indicate the same or equivalent parts or members.
Further, the embodiments shown below exemplify a light emitting module and a method for manufacturing the light emitting module for embodying the technical idea of the present invention, and do not limit the present invention to the following. In addition, the dimensions, materials, shapes, relative arrangements, etc. of the components described below are not intended to limit the scope of the present invention to the specific description, but are exemplified. It was intended. Further, the contents described in one embodiment and the embodiment can be applied to other embodiments and the examples. In addition, the size and positional relationship of the members shown in the drawings may be exaggerated in order to clarify the explanation.

(Liquid crystal display device 1000)
FIG. 1 is a configuration diagram showing each configuration of a liquid crystal display device 1000 including a light emitting module according to the present embodiment. The liquid crystal display device 1000 shown in FIG. 1 includes a liquid crystal panel 120, two lens sheets 110a and 110b, a diffusion sheet 110c, and a light emitting module 100 in this order from the upper side. The liquid crystal display device 1000 shown in FIG. 1 is a so-called direct type liquid crystal display device in which a light emitting module 100 is laminated below the liquid crystal panel 120. The liquid crystal display device 1000 irradiates the liquid crystal panel 120 with the light emitted from the light emitting module 100. In addition to the above-mentioned constituent members, members such as a polarizing film and a color filter may be further provided.

(Light emitting module 100)
The configuration of the light emitting module of this embodiment is shown in FIGS. 2 and 3. FIG. 2 is a schematic plan view of the light emitting module according to the present embodiment. FIG. 3 is a partially enlarged schematic cross-sectional view showing a light emitting module according to the present embodiment, and is a view in which a light guide plate is arranged downward and turned upside down.
The light emitting module 100 shown in these figures includes a light guide plate 1 and a plurality of light emitting element units 3 arranged in recesses 1b of the light guide plate 1. In the light emitting module 100 shown in these figures, a plurality of recesses 1b are provided in one light guide plate 1, and the light emitting element unit 3 is fixed to each recess 1b. However, as shown in the schematic bottom view of FIG. 4, the light emitting module is provided with one recess 1b in the light guide plate 1', and the light emitting element unit 3 is fixed to the recess 1b to form a light emitting bit 5, and a plurality of light emitting bits. 5 can be arranged to form a light emitting module 100'. Further, in the light emitting module 100 shown in FIG. 3, the light emitting element unit 3 is provided with a first sealing resin portion 15A in which the outer peripheral surface is flush with the outer peripheral surface of the light adjusting portion 10 and the light emitting element 11 is embedded. A second sealing resin portion 15B for embedding the light emitting element unit 3 is provided on the second main surface 1d of the light guide plate 1 to which the light emitting element unit 3 is fixed.

The light emitting element unit 3 has the light emitting element 11 fixed to the surface of the light adjusting unit 10 having the wavelength conversion unit 12. The light emitting element 11 has an electrode forming surface 11d on the upper surface and a light emitting surface 11c on the lower surface. The light emitting element 11 mainly emits light from the light emitting surface 11c to irradiate the light adjusting unit 10 with light. In the light emitting module 100 of FIGS. 2 and 3, a plurality of light emitting element units 3 are arranged in recesses 1b provided in a matrix on the light guide plate 1 and fixed to the light guide plate 1. The light guide plate 1 is provided with a plurality of recesses 1b on the second main surface 1d, with the first main surface 1c as a light emitting surface that radiates light to the outside. A part of the light emitting element unit 3 and the light adjusting unit 10 in the figure are arranged in the recess 1b. The optical adjustment unit 10 includes a wavelength conversion unit 12. The light adjusting unit 10 of FIG. 2 has a light diffusing unit 13 laminated on the wavelength conversion unit 12. In the light adjustment unit 10, the wavelength conversion unit 12 is laminated on the light emitting element 11 side, and the light diffusion unit 13 is laminated on the light guide plate 1 side. The light adjusting unit 10 can diffuse the light transmitted through the wavelength conversion unit 12 by the light diffusing unit 13 and irradiate the light guide plate 1 with the light emitted from the light guide plate 1 more uniformly.

In the light emitting module 100 according to the present invention, the light emitting element unit 3 in which the light guide plate 1 is provided with the recess 1b and the light adjusting unit 10 including the wavelength conversion unit 12 is fixed to the recess 1b is arranged. Can be made thinner. Further, since the light emitting element unit 3 is arranged and fixed in the recess 1b by providing the light emitting element 1b in the light guide plate 1, the light emitting element unit 3 is compared with the light emitting module in which the light emitting element is mounted on the substrate and the light emitting element is combined. And the light guide plate 1 can be prevented from being displaced. In particular, in this light emitting module 100, the wavelength conversion unit 12 is bonded to the light emitting element 11, and the light emitting element unit 3 in which the light emitting element 11 and the light adjusting unit 10 are integrated is arranged in the recess 1b of the light guide plate 1. Therefore, both the wavelength conversion unit 12 and the light emitting element 11 can be arranged at an accurate position of the light guide plate 1 to realize good optical characteristics. In particular, in the light emitting module 100 in which the light of the light emitting element 11 is transmitted through the wavelength conversion unit 12 and guided to the light guide plate 1 to be radiated to the outside, the light emitting element 11, the wavelength conversion unit 12 and the light guide plate 1 are not displaced from each other. Since it can be arranged, the light emission characteristics such as color unevenness and brightness unevenness of the light radiated from the light guide plate 1 to the outside are improved, and particularly excellent light emission characteristics are realized.

In a direct-type liquid crystal display device, since the distance between the liquid crystal panel and the light emitting module is short, color unevenness and brightness unevenness of the light emitting module may affect the color unevenness and brightness unevenness of the liquid crystal display device. Therefore, as a light emitting module of a direct type liquid crystal display device, a light emitting module having less color unevenness and brightness unevenness is desired.

By adopting the configuration of the light emitting module 100 of the present embodiment, it is possible to reduce brightness unevenness and color unevenness while reducing the thickness of the light emitting module 100 to 5 mm or less, 3 mm or less, 1 mm or less, and the like.

Each member constituting the light emitting module 100 according to the present embodiment and a manufacturing method will be described in detail below.

(Light guide plate 1)
The light guide plate 1 is a translucent member that makes light incident from a light source planar and radiates it to the outside. As shown in FIG. 2, the light guide plate 1 of the present embodiment includes a first main surface 1c serving as a light emitting surface and a second main surface 1d opposite to the first main surface 1c. The light guide plate 1 is provided with a plurality of recesses 1b on the second main surface 1d, and V grooves 1e are provided between adjacent recesses 1b. A part of the light emitting element unit 3 is arranged in the recess 1b. By inserting a part of the light emitting element 11 into the recess 1b of the light guide plate 1, the entire light emitting module can be made thinner. As shown in FIGS. 2 and 3, the light guide plate 1 is provided with a plurality of recesses 1b and a light emitting element unit 3 is arranged in each recess 1b to form a light emitting module 100, or as shown in FIG. 4, one light guide plate 1 is provided. One light emitting element unit 3 can be arranged in the light guide plate 1'with the recess 1b to form a light emitting bit 5, and a plurality of light emitting bits 5 can be arranged in a plane to form a light emitting module 100'. As shown in FIG. 3, the light guide plate 1 provided with the plurality of recesses 1b is provided with grid-shaped V-grooves 1e between the recesses 1b. As shown in FIG. 4, the light guide plate 1 provided with one recess 1b is provided with an inclined surface 1f having a downward slope toward the outer peripheral edge on the outer peripheral portion of the second main surface 1d.

The V-groove 1e and the inclined surface 1f are provided with a sealing resin portion 15 which will be described later and which reflects light. The sealing resin portion 15 filled in the V-groove 1e is preferably a white resin that reflects light, and the sealing resin portion 15 of the white resin is adjacent to the white resin sealing resin portion 15 in which the light emission of the light emitting element 11 is partitioned by the V-groove 1e. It prevents the light from entering the light guide plate 2 and prevents the light of each light emitting element 11 from leaking to the side. The sealing resin portion 15 joined to the inclined surface 1f provided on the outer peripheral portion of the second main surface 1d of one light guide plate 1 prevents light from leaking around the light guide plate 1 and prevents light from leaking to the periphery of the light guide plate 1. Prevents a decrease in light emission intensity from the first main surface 11c.

The size of the light guide plate 1 is set to an optimum size depending on the number of recesses 1b. For example, in the light guide plate 1 having a plurality of recesses 1b, one side can be about 1 cm to 200 cm. It is preferably about 3 cm to 30 cm. The thickness can be about 0.1 mm to 5 mm, preferably 0.5 mm to 3 mm. The planar shape of the light guide plate 1 can be, for example, a substantially rectangular shape, a substantially circular shape, or the like.

As the material of the light guide plate 1, a thermoplastic resin such as acrylic, polycarbonate, cyclic polyolefin, polyethylene terephthalate and polyester, a resin material such as a thermosetting resin such as epoxy and silicone, and an optically transparent material such as glass are used. be able to. In particular, a thermoplastic resin material is preferable because it can be efficiently produced by injection molding. Of these, polycarbonate, which has high transparency and is inexpensive, is preferable. In the manufacturing process, a light emitting module manufactured without being exposed to a high temperature environment such as reflow solder can be used even if it is a thermoplastic and low heat resistant material such as polycarbonate.

The light guide plate 1 can be molded by injection molding or transfer molding, for example. The light guide plate 1 can be mass-produced at low cost while reducing the misalignment of the recess 1b by forming the light guide plate 1 in a shape having the recess 1b with a mold. However, the light guide plate may be formed into a plate shape and then machined by an NC processing machine or the like to provide a recess.

The light guide plate 1 of the present embodiment may be formed of a single layer, or may be formed by stacking a plurality of translucent layers. When a plurality of translucent layers are laminated, it is preferable to provide layers having different refractive indexes, for example, an air layer, between arbitrary layers. As a result, it becomes easier to diffuse the light, and it is possible to obtain a light emitting module with reduced brightness unevenness. Such a configuration can be realized, for example, by providing a spacer between any plurality of translucent layers to separate them and providing an air layer. Further, a translucent layer on the first main surface 1c of the light guide plate 1 and a layer having a different refractive index between the first main surface 1c of the light guide plate 1 and the translucent layer, for example, an air layer and the like. May be provided. As a result, it becomes easier to diffuse the light, and the liquid crystal display device with reduced luminance unevenness can be obtained. Such a configuration can be realized, for example, by providing a spacer between an arbitrary light guide plate 1 and a translucent layer to separate them, and providing an air layer.

(Optical function unit 1a)
The light guide plate 1 may be provided with an optical function unit 1a on the first main surface 1c side. The optical function unit 1a can have, for example, a function of spreading light in the plane of the light guide plate 1. For example, a material having a refractive index different from that of the light guide plate 1 is provided. Specifically, it is a recess such as an inverted cone, an inverted quadrangular pyramid, or an inverted hexagonal pyramid provided on the 1c side of the first main surface, or a recess such as an inverted truncated cone or an inverted truncated cone. Therefore, one that reflects the light emitted at the interface between the light guide plate 1, a material having a different refractive index (for example, air), and the inclined surface of the recess in the lateral direction of the light emitting element unit 3 can be used. Further, for example, a light-reflecting material (for example, a reflective film such as metal or a white resin) may be provided in the recess 1b having an inclined surface. The inclined surface of the optical functional unit 1a may be a straight line or a curved line in a cross-sectional view. As will be described later, the optical functional unit 1a is preferably provided at a position corresponding to each light emitting element unit 3, that is, at a position opposite to the light emitting element unit 3 arranged on the second main surface 1d side. In particular, it is preferable that the optical axis of the light emitting element unit 3 and the optical axis of the optical functional unit 1a substantially coincide with each other. The size of the optical function unit 1a can be appropriately set.

(Recess 1b)
The light guide plate 1 is provided with a recess 1b on the second main surface 1d side. The recess 1b is arranged at a fixed position by arranging a part of the light emitting element unit 3 inside. The recess 1b shown in FIG. 3 is provided with a recess 1b having a shape in which a part of the second main surface 1d is cut off. However, although not shown, the recess may be provided inside the ridge by providing an annular ridge on the second main surface. The inner shape of the recess 1b is larger than the outer shape of the insertion portion 17 in which the light emitting element unit 3 is arranged in the recess 1b. A ring gap 18 is provided between the insertion portion 17 and the outer periphery of the insertion portion 17. The ring gap 18 is filled with the bonding agent 14 to form a bonding wall 19. The inner shape of the recess 1b has a shape in which the volume of the ring gap 18 is larger than the volume of the insertion portion 17 of the light emitting element unit 3. In the light emitting module of the present embodiment, since the light adjusting unit 10 is arranged in the recess 1b of the light guide plate 1, the light adjusting unit 10 is used as the insertion unit 17 of the light emitting element unit 3. However, the insertion unit 17 of the light emitting element unit 3 is not specified by the light adjustment unit 10, and may be, for example, an insertion unit 17 in which a part of the light adjustment unit 10 and the light emitting element 11 is arranged in the recess 1b.

The inner shape of the recess 1b has a size such that the capacity of the ring gap 18 is, for example, 1.2 times or more, preferably 1.5 times or more, more preferably 2 times or more the volume of the insertion portion 17 of the light emitting element unit 3. Is set to. The ring gap 18 is filled with the translucent bonding agent 14 to form a bonding wall 19. In the light guide plate 1 of FIG. 4, the inner shape of the recess 1b is a quadrangle, and the outer shape of the insertion portion 17 of the light emitting element unit 3 arranged therein is also a quadrangle. The quadrangular insertion portion 17 is arranged in the recess 1b in a posture in which each side intersects the quadrangular recess 1b, in other words, in a posture of rotating with respect to the quadrangular recess 1b, and the recess 1b and the insertion portion 17 are arranged. A ring gap 18 is provided between them. The insertion portion 17 in this figure is arranged in the recess 1b in a posture in which each side is tilted by 45 degrees. The inner shape of the recess 1b in which the insertion portion 17 is arranged in this posture is at least twice the outer shape of the insertion portion 17.

The light guide plate 1 in which the insertion portion 17 is arranged in the recess 1b in the posture shown in FIG. 4 has a feature that the uneven brightness of the first main surface 1c can be reduced. This is because the light radiated from each side of the insertion portion 17 to the surroundings is strongly radiated in the direction of the arrow A shown by the chain line in FIG. 5, and illuminates the C region in the figure brightly. In the quadrangular insertion portion 17, the intensity of the light in the direction indicated by the arrow A orthogonal to each side is stronger than the light radiated from the corner in the direction indicated by the arrow B. In FIG. 5, the C region tends to be darker because it is located farther from the insertion portion 17 than the D region, but the light in the direction indicated by the arrow A is stronger than the direction indicated by the arrow B, so that the brightness is reduced. It is prevented and uneven brightness is reduced. As shown in FIG. 6, when the quadrangular insertion portions 17 are arranged in the quadrangular recess 1b in a parallel posture, the C region is located at a position farther from the insertion portion 17 than the D region, and moreover, from the insertion portion 17. Since the intensity of the emitted light is also reduced, the brightness of the C region is lower than that of the D region.

The recess 1b, which has an inner shape larger than the outer shape of the insertion portion 17, can increase the degree of freedom in the posture in which the insertion portion 17 is arranged to prevent uneven brightness, and the bonding agent 14 to fill the ring gap 18. It also realizes a feature that the deviation of the surface level due to the error of the filling amount of the recess 1b can be eliminated and the light distribution of the outer peripheral portion of the recess 1b can be made into an ideal state. The ring gap 18 is filled with the bonding agent 14 to form a translucent bonding wall 19, but an error in the filling amount of the bonding agent 14 fluctuates the surface level and causes the light emission to be disturbed. 7 and 8 show a state in which the liquid level of the bonding wall 19 is deviated due to an error in the filling amount of the bonding agent 14. FIG. 7 shows a state in which the filling amount of the bonding agent 14 is too small. The surface level of the joint wall 19 is lower than that of the second main surface 1d of the light guide plate 1 and is lowered to the inside of the ring gap 18, so that a gap is formed between the light guide plate 1 and the insertion portion 17. FIG. 8 shows a state in which the filling amount of the bonding agent 14 is too large, and the bonding wall 19 in this state is in a state in which the bonding agent 14 leaks from the ring gap 18 and rises on the second main surface 1d. The gap between the light guide plate 1 and the insertion portion 17 and the bonding agent 14 raised on the second main surface 1d change the path of the light incident on the light guide plate 1 from the insertion portion 17 and cause the light emission to be disturbed.

The structure in which the inner shape of the recess 1b is made larger than the insertion portion 17 and the volume of the ring gap 18 is made larger than the volume of the insertion portion 17 is a liquid due to the variation in the filling amount of the bonding agent 14 to be filled in the ring gap 18. The fluctuation of the surface level is reduced, and the light emission in the region between the light guide plate 1 and the insertion portion 17 is set to an ideal state.

In consideration of the outer shape of the insertion portion 17 and the above characteristics, the size of the recess 1b in a plan view is the diameter in the case of a circle, the major axis in the case of an ellipse, and the diagonal length in the case of a quadrangle. For example, it can be 0.05 mm to 10 mm, preferably 0.1 mm to 2 mm. The depth can be 0.05 mm to 4 mm, preferably 0.1 mm to 1 mm. The distance between the optical function unit 1a and the recess 1b can be appropriately set within a range in which the optical function unit 1a and the recess 1b are separated from each other. The plan-view shape of the recess 1b can be, for example, a substantially rectangular shape or a substantially circular shape, and can be selected depending on the arrangement pitch of the recess 1b and the like. When the arrangement pitch of the recesses 1b (the distance between the centers of the two closest recesses 1b) is substantially equal, a substantially circular shape or a substantially square shape is preferable. Above all, the substantially circular shape is effective in spreading the light from the light emitting element unit 3 satisfactorily.

(Light emitting element unit 3)
The light emitting element unit 3 is a light source of the light emitting module 100. As shown in FIG. 3, the light emitting element unit 3 has a light adjusting unit 10 having a wavelength conversion unit 12 bonded to the light emitting element 11. Further, the light emitting element unit 3 of the present embodiment is provided with a first sealing resin portion 15A in which the outer peripheral surface is flush with the outer peripheral surface of the light adjusting portion 10 and the light emitting element 11 is embedded. The light emitting element unit 3 is arranged in the recess 1b of the light guide plate 1 and radiates light emission to the outside through the light guide plate 1. The light emitting element unit 3 in the figure is arranged inside the recess 1b as an insertion portion 17 in which the light adjusting portion 10 is arranged in the recess 1b of the light guide plate 1. The light emitting element unit 3 is fixed to the recess 1b provided in the light guide plate 1 by joining the light adjusting portion 10 to the bottom surface of the recess 1b.

In the light emitting element unit 3 of FIG. 3, the light adjusting unit 10 is bonded to the light emitting surface 11c of the light emitting element 11. The light emitting element 11 has a light emitting surface 11c on the opposite side of the electrode forming surface 11d, and the light adjusting portion 10 is bonded to this surface. The light emitting module of the present embodiment uses a face-down type in which the opposite side of the electrode forming surface 11d is the light emitting surface 11c and the light emitting surface 11c is the main light emitting surface, but a face-up type light emitting element is also used. it can. The light emitting element 11 of FIG. 3 has an electrode forming surface 11d on the side opposite to the light emitting surface 11c, and a pair of electrodes 11b is provided on the electrode forming surface 11d. The pair of electrodes 11b are wired and electrically connected by a structure described later. The light emitting element unit 3 and the light guide plate 1 are joined via a light-transmitting bonding material 14 such as a translucent resin.

The light emitting element 11 has, for example, a translucent substrate such as sapphire and a semiconductor laminated structure laminated on the translucent substrate. The semiconductor laminated structure includes a light emitting layer, an n-type semiconductor layer and a p-type semiconductor layer sandwiching the light emitting layer, and the n-side electrode and the p-side electrode 11b are electrically connected to the n-type semiconductor layer and the p-type semiconductor layer, respectively. Will be done. In the light emitting element 11, for example, a light emitting surface 11c provided with a translucent substrate is arranged so as to face the light guide plate 1, and the light emitting element 11 has a pair of electrodes 11b on an electrode forming surface 11d opposite to the light emitting surface 11c.

The light emitting element 11 is not particularly limited in the vertical, horizontal and height dimensions, but preferably a semiconductor light emitting device 11 having a vertical and horizontal dimension of 1000 μm or less in a plan view is used, and more preferably the vertical and horizontal dimensions. Is 500 μm or less, and more preferably, a light emitting element 11 having a vertical and horizontal dimension of 200 μm or less is used. When such a light emitting element 11 is used, a high-definition image can be realized when the liquid crystal display device 1000 is locally dimmed. Further, if the light emitting element 11 having vertical and horizontal dimensions of 500 μm or less is used, the light emitting element 11 can be procured at low cost, so that the light emitting module 100 can be made cheap. In the light emitting element 11 having both the vertical and horizontal dimensions of 250 μm or less, the area of the upper surface of the light emitting element 11 is small, so that the amount of light emitted from the side surface of the light emitting element 11 is relatively large. That is, since the light emitting element 11 tends to emit light in a butt wing shape, the light emitting element 11 is bonded to the light guide plate 1, and the distance between the light emitting element 11 and the light guide plate 1 is very short. It is preferably used for 100.

Further, the light guide plate 1 can be provided with an optical function unit 1a having a reflecting or diffusing function such as a lens. The light guide plate 1 can spread the light from the light emitting element 11 laterally and average the light emission intensity in the plane of the light guide plate 1. However, it may be difficult for the light guide plate 1 in which the plurality of optical function units 1a are formed at the corresponding positions of the plurality of light emitting elements 11 to accurately maintain the relative positions of all the light emitting elements 11 and the optical function units 1a. is there. In particular, in a structure in which a large number of small light emitting elements 11 are provided, it is difficult to accurately maintain the relative positions of all the light emitting elements 11 and the optical functional unit 1a. The deviation of the relative position between the light emitting element 11 and the optical function unit 1a causes uneven brightness due to the light cannot be sufficiently spread by the optical function unit 1a and the brightness is partially reduced in the plane. There is a problem. In particular, in the method of combining the light emitting element 11 after mounting the light emitting element 11 on the wiring board, the positional deviation between the wiring board and the light emitting element 11 and the positional deviation between the optical function portion 1a of the light guide plate 1 are flat. Since it is necessary to take into consideration the direction and the stacking direction, it may be more difficult to satisfactorily optically couple the light emitting element 11 and the optical functional unit 1a.

The light emitting module 100 in the present embodiment has a structure in which a plurality of recesses 1b and an optical function unit 1a are provided in the light guide plate 1 and the light emitting element unit 3 is arranged in the recess 1b. Both can be placed with high position accuracy. As a result, the light from the light emitting element 11 can be accurately uniformized by the optical function unit 1a, and a high-quality backlight light source with less luminance unevenness and color unevenness can be obtained.

The light guide plate 1 provided with the optical function unit 1a on the surface opposite to the recess 1b on which the light emitting element 11 is arranged emits light by providing the optical function unit 1a at the position of the recess 1b on which the light emitting element 11 is arranged in plan perspective. The positioning of the element 11 and the optical functional unit 1a can be made easier, and the elements 11 and the optical functional unit 1a can be arranged with high positional accuracy without relative displacement.

As the light emitting element 11, a square or rectangular light emitting element 11 in a plan view is used. The light emitting element 11 used in the high-definition liquid crystal display device preferably uses a rectangular light emitting element, and its upper surface shape preferably has a long side and a short side. In the case of a high-definition liquid crystal display device, the number of light emitting elements used is several thousand or more, and the mounting process of the light emitting elements is an important process. Even if a rotational deviation (for example, a deviation in the ± 90 degree direction) occurs in some of the light emitting elements of the plurality of light emitting elements in the mounting process of the light emitting element, it can be visually confirmed by using a rectangular light emitting element in a plan view. Becomes easier. Further, since the p-type electrode and the n-type electrode can be formed at a distance from each other, the wiring 21 described later can be easily formed. On the other hand, when the square light emitting element 11 is used in a plan view, the small light emitting element 11 can be manufactured with good mass productivity. The density (arrangement pitch) of the light emitting elements 11, that is, the distance between the light emitting elements 11 can be, for example, about 0.05 mm to 20 mm, preferably about 1 mm to 10 mm.

The light emitting module 100 in which a plurality of light emitting element units 3 are arranged in a light guide plate 1 having a plurality of recesses 1b arranges the light emitting element units 3 in two dimensions in a plan view of the light guide plate 1. Preferably, as shown in FIG. 2, the plurality of light emitting element units 3 are arranged in recesses 1b that are two-dimensionally arranged along two orthogonal directions, that is, the x direction and the y direction. The arrangement pitch p _x in the x direction of the recess 1b arranging a plurality of light emitting unit 3, the arrangement pitch p _y in the y direction, as shown in the example of FIG. 2, the pitch is the same between the x and y directions It may be, or it may be different. Also, the two directions of the array do not necessarily have to be orthogonal. Further, the arrangement pitch in the x-direction or the y-direction is not limited to equal intervals, and may be unequal intervals. For example, recesses 1b for arranging the light emitting element units 3 may be arranged so that the distance between the light guide plate 1 is widened from the center to the periphery. The pitch between the light emitting element units 3 arranged in the recess 1b is the distance between the optical axes of the light emitting element unit 3, that is, the distance between the centers.

A known semiconductor light emitting device can be used as the light emitting element 11. In this embodiment, a face-down type light emitting diode is exemplified as the light emitting element 11. The light emitting element 11 emits blue light, for example. As the light emitting element 11, an element that emits light other than blue can be used, and a face-up type light emitting element can also be used. Further, as the plurality of light emitting elements 11, light emitting elements that emit light of different colors may be used. The emission color of the light emitted from the light emitting element 11 is adjusted by the wavelength conversion unit 12 to the outside.

As the light emitting element 11, an element that emits light having an arbitrary wavelength can be selected. For example, blue, as the device that emits green light, using the light-emitting element using a nitride-based semiconductor _{(In x Al y Ga1 -xy N} , 0 ≦ X, 0 ≦ Y, X + Y ≦ 1) or GaP Can be done. Further, as the element that emits red light, a light emitting element containing a semiconductor such as GaAlAs or AlInGaP can be used. Further, a semiconductor light emitting device made of a material other than these can also be used. Various emission wavelengths can be selected depending on the material of the semiconductor layer and its mixed crystalliteness. The composition, emission color, size, number, etc. of the light emitting element to be used may be appropriately selected according to the purpose.

(Light adjustment unit 10)
In the present embodiment, the light emitting element unit 3 is provided with a light adjusting unit 10 that adjusts the color emitted from the light emitting element 11 and is incident on the light guide plate 1. The light adjustment unit 10 includes a wavelength conversion unit 12 that adjusts the emission color of the light emitting element 11. The light adjusting unit 10 is joined to the light emitting surface 11c of the light emitting element 11 to adjust the light emitting color of the light emitting element 11. The light adjusting unit 10 preferably includes a wavelength conversion unit 12 and a light diffusing unit 13. The light adjustment unit 10 joins the wavelength conversion unit 12 and the light diffusion unit 13 and arranges the wavelength conversion unit 12 on the light emitting element 11 side. The light adjustment unit 10 can also stack a plurality of wavelength conversion units 12 and light diffusion units 13. In the light emitting module 100 of the present embodiment, the light adjusting unit 10 is arranged in the recess 1b of the light guide plate 1 to serve as the insertion unit 17 of the light emitting element unit 3. The light adjusting unit 10 transmits the light incident from the light emitting element 11 and incidents on the light guide plate 1. The light adjusting unit 10 is preferably inside the recess 1b of the light guide plate 1 and protrudes from the second main surface 1d to the surface side as shown in FIG. 3 for the purpose of reducing the thickness of the light emitting module 100. It is arranged in the recess 1b. The light adjusting unit 10 of FIG. 3 has a thickness equal to the depth of the recess 1b, and its surface is arranged on the same plane as the second main surface 1d. However, although not shown, the light adjusting portion may have a thickness inside the recess and slightly protruding from the second main surface of the light guide plate to the surface side.

In the light emitting element unit 3 of FIG. 3, the outer shape of the light adjusting unit 10 is larger than the outer shape of the light emitting element 11. The light emitting element unit 3 can reduce color unevenness by transmitting all the light emitted from the light emitting surface 11c of the light emitting element 11 through the light adjusting unit 10 and incident on the light guide plate 1.

The wavelength conversion unit 12 adds a wavelength conversion material to the base material, and the light diffusing unit 13 adds a diffusing material to the base material. As the material of the base material, for example, an epoxy resin, a silicone resin, a resin in which these are mixed, or a translucent material such as glass can be used. From the viewpoint of light resistance and moldability of the light adjusting unit 10, it is beneficial to select a silicone resin as the base material. As the base material of the light adjusting unit 10, a material having a higher refractive index than the material of the light guide plate 1 is preferable.

Examples of the wavelength conversion material contained in the wavelength conversion unit 12 include a fluoride-based phosphor such as a YAG phosphor, a β-sialone phosphor, and a KSF-based phosphor. In particular, a plurality of types of wavelength conversion members are used in one wavelength conversion unit 12, more preferably a β-sialon phosphor that emits green light and a KSF phosphor that emits red light. By including the fluoride-based phosphor of the above, the color reproduction range of the light emitting module can be expanded. In this case, the light emitting element 11, capable of nitride semiconductor that emits light of short wavelength that can efficiently excite the wavelength converting member _{(In x Al y Ga 1-} xy N, 0 ≦ X, 0 ≦ Y, X + Y It is preferable to provide ≦ 1). Further, for example, 60% by weight of a KSF-based phosphor (red phosphor) is added to the wavelength conversion unit 12 so that red-based light can be obtained when the light emitting element 11 that emits blue-based light is used. As described above, preferably 90% by weight or more may be contained. That is, the wavelength conversion unit 12 may include a wavelength conversion member that emits light of a specific color so that light of a specific color is emitted. Further, the wavelength conversion material may be quantum dots. The wavelength conversion material may be arranged in any way in the wavelength conversion unit 12. For example, it may be distributed substantially uniformly, or may be unevenly distributed in a part. Further, a plurality of layers each containing a wavelength conversion member may be laminated and provided.

As the light diffusing unit 13, for example, a resin material described above may be used as a base material, and a material containing white inorganic fine particles such as _{SiO 2} and TiO _{2 may be used.}

(Encapsulating resin portion 15)
The light emitting module 100 of FIG. 3 is provided by joining the sealing resin portion 15 to the second main surface 1d of the light guide plate 1. The sealing resin portion 15 is preferably a white resin in which white powder or the like, which is an additive that reflects light, is added to the transparent resin. The white resin sealing resin portion 15 includes light radiated from the outer peripheral portion and the electrode surface of the light emitting element 11, light radiated from the back surface of the light adjusting portion 10, and light radiated from the back surface of the joint wall 19. The light emitted from the second main surface 1d of the light guide plate 1 is reflected, and the light emitted from the light emitting element 11 is effectively radiated to the outside from the first main surface 1c of the light guide plate 1. In the light emitting module 100 of FIG. 3, the sealing resin portion 15 is divided into a first sealing resin portion 15A and a second sealing resin portion 15B. The light emitting module 100 in this figure has a second sealing resin portion 15 joined to a first sealing resin portion 15A having an integral structure with the light emitting element unit 3 and a second main surface 1d of the light guide plate 1. Although it is divided into the sealing resin portion 15B, the sealing resin portion may have an integral structure without partitioning the first sealing resin portion and the second sealing resin portion. This light emitting module is manufactured by fixing a light emitting element unit without a first sealing resin portion to a light guide plate and then joining the sealing resin portion to a second main surface of the light guide plate.

In the light emitting module 100 that partitions the first sealing resin portion 15A and the second sealing resin portion 15B, the light emitting element 11 and the light adjusting portion 10 are connected to the first sealing resin portion in the manufacturing process of the light emitting module 100. The 15A is joined, and the first sealing resin portion 15A is manufactured in a state where the light emitting element 11 and the light adjusting portion 10 are a block having an integral structure. The second sealing resin portion 15B is joined to the second main surface 1d of the light guide plate 1 in a state where the light emitting element unit 3 provided with the first sealing resin portion 15A is joined to the light guide plate 1. The gap of the first sealing resin portion 15A is filled.

The first sealing resin portion 15A and the second sealing resin portion 15B are in close contact with each other. Further, the first sealing resin portion 15A is also in close contact with the light emitting element 11. In the first sealing resin portion 15A, the light emitting element 11 is embedded around the light emitting element 11 to expose the electrode 11b of the light emitting element 11 to the surface. The first sealing resin portion 15A has an outer peripheral surface flush with the outer peripheral surface of the light adjustment portion 10 and is in close contact with the light adjustment portion 10. The first sealing resin portion 15A is manufactured as a light emitting element unit 3 integrally joined to the light emitting element 11 and the light adjusting portion 10, and is fixed to the light guide plate 1. Further, the first sealing resin portion 15A is preferably a white resin, and the first sealing resin portion 15A reflects the light emitted toward the outer peripheral surface of the light emitting element 11 to cause the light emitting module 100. Luminous efficiency can be increased. The second sealing resin portion 15B is brought into close contact with the second main surface 1d of the light guide plate 1 at the boundary between the back surface of the joint wall 19. The second sealing resin portion 15B is provided on the same plane as the surface of the first sealing resin portion 15A where the electrode 11b is exposed. The second sealing resin portion 15B is joined to the second main surface 1d of the light guide plate 1 to which the light emitting element unit 3 having the first sealing resin portion 15A as an integral structure is fixed, and is first sealed. It is provided between the resin portions 15A.

The second sealing resin portion 15B is laminated on the light guide plate 1 to reinforce the light guide plate 1. Further, the second sealing resin portion 15B is preferably a white resin, and the sealing resin portion 15 efficiently takes in the light emitted from the light emitting element 11 into the light guide plate 1 to form the first main surface 1c of the light guide plate 1. The light emission output can be increased. Furthermore, the second sealing resin portion 15B, which is a white resin, serves as a member for protecting the light emitting element 11 and a layer for reflecting the surface of the second main surface 1d of the light guide plate 1, thereby forming the light emitting module 100. It can be made thinner.

The sealing resin portion 15 is preferably a white resin having a reflectance of 60% or more, preferably 90% or more, with respect to the light emitted from the light emitting element 11. The sealing resin portion 15 is preferably a resin containing a white pigment such as white powder. In particular, a silicone resin containing an inorganic white powder such as titanium oxide is preferable. As a result, the light emitting module 100 can be made inexpensive by using a large amount of an inexpensive raw material such as titanium oxide as a material used in a relatively large amount to cover one surface of the light guide plate 1.

(Translucent joint member)
In the light emitting module 100 of FIG. 3, the wavelength conversion unit 12, the light diffusing unit 13, the light adjusting unit 10, the light emitting element 11, the light emitting element unit 3 and the light guide plate 1 are joined by a translucent joining member. The translucent bonding member is formed by joining the wavelength conversion unit 12 and the light diffusing unit 13 to form a light adjusting unit 10, and joining the light adjusting unit 10 and the light emitting element 11 to form a light emitting element unit 3. The translucent joining member 16A, which is a bonding agent 14 for joining the light emitting element unit 3 and the bottom surface of the recess 1b of the light guide plate 1, fixes the light emitting element unit 3 to the light guide plate 1, and the recess 1b and the light emitting element unit 3 The translucent bonding member 16A, which is a bonding agent 14 formed by filling the ring gap 18 with the insertion portion 17, constitutes a bonding wall 19 and joins the light adjusting portion 10 to the inner surface of the recess 1b. ..

The translucent bonding member has a light transmittance of 60% or more, preferably 90% or more. The translucent bonding member 16A propagates the light emitted from the light emitting element 11 to the light guide plate 1. The translucent bonding member 16A is a translucent resin that contains a diffusing member or the like, or can contain a white powder or the like that is an additive that reflects light, but does not contain a diffusing member or the white powder or the like. It may be composed of only the material.

As the material of the translucent bonding member, a translucent thermosetting resin material such as an epoxy resin or a silicone resin can be used.

(Manufacturing process of light emitting module 100)
9A-9D and 10A-10D show the manufacturing process of the light emitting element unit 3 according to the present embodiment.
In the steps shown in FIGS. 9A and 9B, the wavelength conversion unit 12 and the light diffusion unit 13 are laminated to form the light adjustment unit 10.
In the step shown in FIG. 9A, the first sheet 31 in which the wavelength conversion unit 12 was attached to the surface of the base sheet 30 with a uniform thickness, and the light diffusing unit 13 were attached to the surface of the base sheet 30 in a uniform thickness. The second sheet 32 is laminated in a state where the wavelength conversion unit 12 and the light diffusion unit 13 are joined. The wavelength conversion unit 12 and the light diffusion unit 13 are joined by a translucent joining member. The length conversion unit 12 and the light diffusion unit 13 are attached to the base sheet 30 so that they can be peeled off via, for example, an adhesive layer.
Further, in the step shown in FIG. 9B, the base sheet 30 of the second sheet 32 is attached to the plate 33 so as to be peeled off, and the base sheet 30 bonded to the wavelength conversion unit 12 of the first sheet 31 is peeled off. ..

In the process shown in FIG. 9C, the light emitting element 11 is bonded to the light adjusting unit 10. The light emitting element 11 joins the light emitting surface 11c side to the light adjusting unit 10. The light emitting element 11 is joined to the wavelength conversion unit 12 of the light adjustment unit 10 at predetermined intervals. The light emitting element 11 is bonded to the light adjusting unit 10 via a translucent bonding member. The translucent joining member is applied to the surface of the light emitting element 10 and the light emitting element 11 to join the light emitting element 11 and the light emitting element 10. FIG. 9C shows a state in which the coated translucent joining member 16B protrudes around the light emitting element 11 and joins the light emitting element 11 to the light adjusting unit 10. As shown in FIG. 10D, the distance between the light emitting elements 11 is set to a dimension in which the outer shape of the light adjusting unit 10 has a predetermined size by cutting between the light emitting elements 11. This is because the distance between the light emitting elements 11 specifies the outer shape of the light adjusting unit 10.

In the process shown in FIG. 9D, the first sealing resin portion 15A is formed so as to embed the light emitting element 11. The first sealing resin portion 15A is preferably a white resin. The first sealing resin portion 15A made of white resin is applied to the surface of the light adjusting portion 10 and cured in a state where the light emitting element 11 is embedded. The first sealing resin portion 15A is applied to a thickness that completely embeds the light emitting element 11, and in the figure, a thickness that embeds the electrode 11b of the light emitting element 11.

In the step shown in FIG. 10A, the cured white resin is polished to expose the electrode 11b of the light emitting element 11.

An electrode terminal 23 may be formed by using a metal film on the electrode 11b of the light emitting element 11. In this case, for example, in the step shown in FIG. 10B, the metal film 22 is provided on the surface of the first sealing resin portion 15A. The metal film 22 is connected to the electrode 11b by providing a metal film such as copper, nickel, or gold on the surface of the first sealing resin portion 15A by sputtering or the like.

In the step shown in FIG. 10C, a part of the metal film 22 is removed, and the metal film 22 is laminated on the electrode 11b to form the electrode terminal 23 of the light emitting element unit 3. Dry etching, wet etching, laser ablation, or the like can be used to remove the metal film 22.

In the step shown in FIG. 10D, the first sealing resin portion 15A made of white resin and the layer to be the light adjusting portion 10 are cut and separated into the light emitting element unit 3. In the separated light emitting element unit 3, the light emitting element 11 is bonded to the light adjusting unit 10, the first sealing resin portion 15A is provided around the light emitting element 11, and the electrode terminal 23 is first sealed. It is exposed on the surface of the resin portion 15A.

The light emitting element unit 3 manufactured in the above steps is joined to the recess 1b of the light guide plate 1 in the steps shown in FIGS. 11A to 11C and 12A to 12C.
The light guide plate 1 is made of polycarbonate. As shown in FIGS. 11A and 11B, the light guide plate 1 is formed by molding a thermoplastic resin such as polycarbonate, forming a recess 1b on the second main surface 1d, and having an inverted conical shape on the first main surface 1c. An optical function unit 1a is provided. The light emitting element unit 3 is joined to the recess 1b of the light guide plate 1. The light emitting element unit 3 is fixed to the light guide plate 1 by inserting the light adjusting portion 10 into the recess 1b coated with the liquid translucent bonding member 16A in an uncured state, curing the translucent bonding member 16A, and fixing the light emitting element unit 3 to the light guide plate 1. The light emitting element unit 3 accurately inserts the light adjusting portion 10 into the center of the recess 1b, cures the translucent joining member 16A, and joins the light emitting element unit 3 to the light guide plate 1. The uncured transparent joining member 16A applied to the recess 1b is extruded into the ring gap 18 in a state where the light emitting element unit 3 is joined to the light guide plate 1, and the surface level of the joining wall 19 is set to the light guide plate 1. The filling amount is adjusted to the same level as the second main surface 1d of. However, in the uncured translucent bonding member, after the light emitting element unit 3 is bonded to the light guide plate 1, the ring gap 18 is filled and the surface level of the bonding wall 19 is set to the second main surface 1d of the light guide plate 1. It can also be on the same plane. Therefore, the filling amount of the uncured transparent joining member 16A that is first filled in the recess 1b is such that the surface level of the joining wall 19 is the second of the light guide plate 1 in the state where the light emitting element unit 3 is joined to the recess 1b. The level is lower than the main surface 1d, that is, a small amount located inside the ring gap 18, and after joining the light emitting element unit 3 to the light guide plate 1, a translucent joining member is later filled in the ring gap 18. The surface level of the joint wall 19 is made flush with the second main surface 1d of the light guide plate 1.

The translucent joining member 16A that joins the light adjusting portion 10 to the bottom surface of the recess 1b is in close contact with the surfaces of both in an uncured state, and is cured to join the surface of the light adjusting portion 10 to the bottom surface of the recess 1b. Further, the translucent joining member 16A extruded from between the light adjusting portion 10 and the bottom surface of the recess 1b serves as a joining wall 19 and joins the outer periphery of the light adjusting portion 10 to the inner peripheral surface of the recess 1b. In this manufacturing method, the uncured and liquid translucent joining member 16A filled in the recess 1b is extruded into the ring gap 18 to form a joining wall 19. In this method, since the translucent bonding member 16A filled in the recess 1b is used as the bonding agent 14, the filling amount of the translucent bonding member 16A is the same for the bonding wall 19 and the second main surface 1d of the light guide plate 1. It is necessary to adjust the amount to be flat. When the filling amount of the translucent joining member 16A is small, the surface of the joining wall 19 becomes lower than the second main surface 1d of the light guide plate 1 as shown in FIG. On the contrary, when the filling amount of the translucent joining member 16A is large, as shown in FIG. 8, the joining wall 19 protrudes from the ring gap 18, and the surface of the joining wall 19 protrudes from the second main surface 1d of the light guide plate 1. To do. Unless the surface of the joint wall 19 is flush with the second main surface 1d of the light guide plate 1, the light distribution around the light emitting portion cannot be in an ideal state. This is because the translucent joining member protruding from the recess 1b and the unfilled gap of the translucent joining member disturb the light distribution. The filling amount of the translucent joint member 16A is adjusted so that the joint wall 19 and the second main surface 1d of the light guide plate 1 are flush with each other, but there is a slight variation in the filling amount between the joint wall 19 and the light guide plate. It causes the relative position of 1 with respect to the second main surface 1d to be deviated.

The light emitting module 100 of the present embodiment prevents the level of the surface of the joint wall 19 and the relative position of the second main surface 1d of the light guide plate 1 from being displaced due to the imbalance of the filling amount of the translucent joint member 16A. The volume of the entire joint wall 19 is made larger than the volume inside the recess, which is the volume of the light emitting element unit 3 arranged in the recess 1b. In the present embodiment, since the light emitting element unit 3 arranges the light adjusting unit 10 in the recess 1b, the volume inside the recess is the volume of the light adjusting unit 10. Therefore, in the present embodiment, the volume of the entire joint wall 19 is made larger than the volume of the light adjusting unit 10. The recess 1b, in which the volume of the entire joint wall 19 is larger than the volume inside the recess of the light emitting element unit 3, can reduce the displacement of the surface of the joint wall with respect to the variation in the filling amount of the translucent joint member 16A to be filled.

For example, as a concrete example
The inner shape of the recess is a quadrangle with a side of 0.6 mm and a depth of 0.2 mm.
The outer shape of the optical adjustment unit is a quadrangle with a side of 0.5 mm and a thickness of 0.2 mm.
If the light adjustment unit is placed in this recess,
The volume inside the recess of the light emitting element unit is 0.05 mm ³ ,
The total volume of the joint wall 19 is 0.022 mm ³ .
The volume of the entire joint wall 19 is about 1/2 of the volume inside the recess.
In this structure, in order to keep the level difference on the surface of the joint wall 19 within ± 0.01 mm,
It is necessary to control the filling amount of the translucent bonding member ^{within ± 0.0036 mm 3 extremely accurately.}

On the contrary,
If the inner shape of the recess 1b is a quadrangle with a side of 1.0 mm and the same depth,
Since the volume inside the recess is the same 0.05 mm ³ ,
The volume of the entire joint wall 19 is as ^{large as 0.15 mm 3} , and if it is about 3 times the volume inside the recess,
To adjust the level difference on the surface of the joint wall 19 within ± 0.01 mm
The error in the filling amount of the translucent bonding member can be increased to within ^{± 0.01 mm 3 by about 2.8 times.}

From this, the light emitting module 100 in which the volume of the ring gap 18 is increased and the total volume of the joint wall 19 is increased absorbs the error of the filling amount of the translucent joining member 16A to be filled in the recess 1b. , The surface level of the joint wall 19 can be arranged exactly on the same plane as the second main surface 1d of the light guide plate 1. Further, since the thick joint wall 19 transmits the light radiated from the light adjustment unit 10 and guides it to the light guide plate 1, a thick joint wall different from the light guide plate 1 is provided between the light guide plate 1 and the light adjustment unit 10. Due to the structure in which 19 is laminated, the light is more uniformly dispersed and radiated from the light guide plate 1 to the outside. Further, the light emitting element unit 3 is joined to the recess 1b so that the surface level of the joining wall 19 is lower than the second main surface 1d of the light guide plate 1, and then the translucent joining member 16A is replenished to the recess 1b. Even in the manufacturing method in which the surface level of the joint wall 19 is flush with the second main surface 1d of the light guide plate 1, the error in the filling amount of the translucent joint member 16A to be replenished in the recess 1b is made into a large-capacity ring gap 18 Can absorb and make the surface level of the joint wall 19 flush with the second main surface 1d.

After the light emitting element unit 3 is fixed to the light guide plate 1, the second sealing resin portion 15B is formed on the second main surface 1d of the light guide plate 1 in the step shown in FIG. 11C. A white resin is used for the second sealing resin portion 15B, and the light emitting element unit 3 is formed to have a thickness embedded therein.

In the step shown in FIG. 12A, the surface of the cured second sealing resin portion 15B is polished to expose the electrode terminal 23 to the surface.
In the step shown in FIG. 11C, the second sealing resin portion 15B was formed to have a thickness for embedding the light emitting element unit 3 inside, but it was formed on the same plane as the surface of the electrode terminal 23 or the surface of the electrode terminal 23. It may be formed to a thickness lower than that of the above-mentioned polishing step.

In the step shown in FIG. 12B, the conductive film 24 is laminated on the surface of the sealing resin portion 15. In this step, a Cu / Ni / Au metal film 24 is formed on substantially the entire surface of the electrode terminal 23 of the light emitting element 11 and the sealing resin portion 15 by sputtering or the like.

In the step shown in FIG. 12C, a part of the conductive film 24 is removed, and each light emitting element 11 is electrically connected via the conductive film 24.

In the above steps, a light emitting module 100 in which a plurality of light emitting element units 3 are fixed to one light guide plate 1 is manufactured. A method of manufacturing the light emitting bit 5 by fixing one light emitting element unit 3 to one light guide plate 1'is a method of manufacturing the light emitting element unit 3 in FIGS. 9A to 9D and FIGS. 10A to 10D, and then FIG. 11A. In the step shown in FIG. 11B, the light emitting element unit 3 is fixed to the recess 1b of the light guide plate 1 provided with one recess 1b, and then the second sealing is performed on the light guide plate 1 in the same manner as in the step shown in FIG. 11C. The resin portion 15B is joined, the surface of the second sealing resin portion 15B is further polished to expose the electrode terminal 23 in the same manner as in the step shown in FIG. 12A, and the conductive film 24 is further laminated in the step shown in FIG. 12B. Then, in the step shown in FIG. 12C, a part of the conductive film 24 is removed, separated into a pair of power supply terminals 23, and the conductive film 24 is electrically connected.

The plurality of light emitting element units 3 may be wired so as to be driven independently of each other. Further, the light guide plate 1 is divided into a plurality of ranges, and the plurality of light emitting element units 3 mounted in one range are grouped into one group, and the plurality of light emitting element units 3 in the one group are connected in series or in parallel. It may be connected to the same circuit by electrically connecting to, and a plurality of such light emitting element unit groups may be provided. By performing such grouping, it is possible to obtain a light emitting module capable of local dimming.

One of the light emitting modules 100 of the present embodiment may be used as a backlight of one liquid crystal display device. Further, a plurality of light emitting modules 100 may be arranged side by side and used as a backlight of one liquid crystal display device 1000. By making a plurality of small light emitting modules 100 and inspecting each of them, the yield can be improved as compared with the case of making a light emitting module 100 having a large number of light emitting elements 11 mounted large.

As shown in FIG. 13, the light emitting module 100 may have a wiring board 25. The wiring board 25 is, for example, electrically connected to the conductive member 26 filled in a plurality of via holes provided in the insulating base material constituting the wiring board 25, and the conductive member 26 on both side surfaces of the base material. The connected wiring layer 27 is formed. Then, the electrode 11b is electrically connected to the wiring layer 27 via the conductive member 26.
In addition, one light emitting module 100 may be bonded to one wiring board. Further, a plurality of light emitting modules 100 may be joined to one wiring board. As a result, the electrical connection terminals (for example, connectors) to the outside can be integrated (that is, it is not necessary to prepare each light emitting module), so that the structure of the liquid crystal display device 1000 can be simplified.

Further, one wiring board to which the plurality of light emitting modules 100 are joined may be arranged side by side to form a backlight of one liquid crystal display device 1000. At this time, for example, a plurality of wiring boards can be placed on a frame or the like and each can be connected to an external power supply by using a connector or the like.

A translucent member having a function such as diffusion may be further laminated on the light guide plate 1. In that case, when the optical function portion 1a is a recess, the opening of the recess (that is, the portion close to the first main surface 1c of the light guide plate 1) is closed, but the translucent member is used so as not to fill the recess. It is preferable to provide. As a result, an air layer can be provided in the recess of the optical functional unit 1a, and the light from the light emitting element 11 can be satisfactorily spread.

The light emitting module according to the present invention can be used, for example, as a backlight of a liquid crystal display device, a lighting fixture, or the like.

1000 ... Liquid crystal display device 100, 100'... Light emitting module 110a ... Lens sheet 110b ... Lens sheet 110c ... Diffusion sheet 120 ... Liquid crystal panel 1, 1'... Light guide plate 1a ... Optical function unit 1b ... Recess 1c ... First main surface 1d Second main surface 1e ... V groove 1f ... Inclined surface 3 ... Light emitting element unit 5 ... Light emitting bit 10 ... Light adjusting unit 11 ... Light emitting element 11b ... Electrode 11c ... Light emitting surface 11d ... Electrode forming surface 12 ... Wavelength conversion unit 13 ... Light diffusing part 14 ... Bonding agent 15 ... Sealing resin part 15A ... First sealing resin part 15B ... Second sealing resin parts 16A, 16B ... Translucent bonding member 17 ... Inserting part 18 ... Ring gap 19 ... Joint wall 22 ... Metal film 23 ... Electrode terminal 24 ... Conductive film 25 ... Wiring substrate 26 ... Conductive member 27 ... Wiring layer 30 ... Base sheet 31 ... First sheet 32 ... Second sheet 33 ... Plate

Claims (12)

A light guide plate including a first main surface serving as a light emitting surface and a second main surface on the opposite side of the first main surface and having a recess.
A light adjustment unit containing a phosphor and
A method for manufacturing a light emitting module including a light emitting element bonded to the light adjusting portion.
With the light guide plate
A light emitting element unit in which the light adjusting unit and the light emitting element are joined to form an integral structure is prepared.
The light adjusting portion of the light emitting element unit having an outer shape smaller than the inner shape of the concave portion is fixed to the concave portion.
A joint wall is formed by filling a ring gap formed between the inner circumference of the recess and the outer circumference of the insertion portion, which is formed by arranging an insertion portion including the light adjusting portion in the recess.
The volume of the ring gap is made larger than the volume of the insertion portion of the light emitting element unit.
A method for manufacturing a light emitting module, in which wiring is formed on the electrodes of the light emitting element. Using the light guide plate provided with a plurality of recesses on the second main surface,
The method for manufacturing a light emitting module according to claim 1, wherein the light emitting element unit is fixed to each of the recesses of the light guide plate, and a plurality of the light emitting element units are fixed to a fixed position of the light guide plate. The method for manufacturing a light emitting module according to claim 1 or 2, wherein the light emitting surface of the light emitting element is arranged on the same plane as the second main surface of the light guide plate, and the light emitting element unit is fixed to the light guide plate. The method for manufacturing a light emitting module according to any one of claims 1 to 3, wherein the surface level of the joint wall is flush with the second main surface of the light guide plate. The method for manufacturing a light emitting module according to any one of claims 1 to 4, wherein a translucent resin is used for the joint wall. The light emitting element unit is provided with a first sealing resin portion in which the outer peripheral surface is flush with the outer peripheral surface of the light adjusting portion and the light emitting element is embedded.
The method for manufacturing a light emitting module according to any one of claims 1 to 5, wherein a light emitting element unit provided with the first sealing resin portion is fixed to the light guide plate. The method for manufacturing a light emitting module according to claim 6, wherein the first sealing resin portion is a white resin. The light emitting module according to any one of claims 1 to 7, wherein a second sealing resin portion for embedding the light emitting element unit is provided on a second main surface of the light guide plate to which the light emitting element unit is fixed. Production method. A translucent light guide plate having a recess on the second main surface opposite to the first main surface, which is a light emitting surface that emits light to the outside.
A light emitting element unit fixed to the recess of the light guide plate is provided.
The light emitting element unit has a light adjusting unit containing a phosphor bonded to the light emitting element.
In the light emitting element unit, the outer shape of the insertion portion arranged in the recess is smaller than the inner shape of the recess.
A translucent bonding agent filled in the ring gap formed between the insertion portion and the recess is provided as a bonding wall.
A light emitting module in which the volume of the ring gap is larger than the volume of the insertion portion of the light emitting element unit. The light emitting module according to claim 9, wherein a second sealing resin portion having the light emitting element unit embedded therein is laminated on the second main surface of the light guide plate. The light emitting element unit has a first sealing resin portion in which the outer peripheral surface is flush with the outer peripheral surface of the light adjusting portion and the light emitting element is embedded.
The light emitting module according to claim 10, wherein the light emitting element unit provided with the first sealing resin portion is embedded in the second sealing resin portion. The light emitting module according to claim 10 or 11, wherein the second sealing resin portion and the first sealing resin portion are white resins.

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