JP7148810B2 - Light-emitting module manufacturing method and light-emitting module - Google Patents

Description

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

A light-emitting module including a light-emitting element such as a light-emitting diode and a light guide plate is widely used as a backlight source for a liquid crystal display, a display, and the like (for example, Patent Documents 1 and 2).

JP 2010-164976 A Japanese Patent Publication No. 2015-525001

An object of the present disclosure is to provide a light-emitting module manufacturing method and a light-emitting module that reduce color shift.

The present disclosure includes the following configurations.
(1) preparing a light guide plate having a first main surface serving as a light emitting surface and a second main surface opposite to the first main surface and having a plurality of recesses;
preparing a wavelength conversion member having an area smaller than the area of the recess in plan view;
A light-emitting element comprising a semiconductor laminate having a first surface and a second surface opposite to the first surface and an electrode disposed on the second surface; and covering a side surface of the light-emitting element and exposing the electrode. providing a light source comprising a covering member for
disposing the wavelength conversion member in the recess;
a step of fixing the light source on the wavelength conversion member with the first surface side of the semiconductor laminate of the light emitting element facing each other;
sealing the light source and the second main surface of the light guide plate with a light reflecting member;
A method of manufacturing a light emitting module comprising:
(2) a light guide plate having a first principal surface serving as a light emitting surface and a second principal surface opposite to the first principal surface and having a plurality of recesses;
a wavelength conversion member disposed within the recess of the light guide plate;
a light source joined to the wavelength conversion member, the light source including a light emitting element and a covering member covering the side surface of the light emitting element;
a light reflecting member that seals the second main surface of the light guide plate and the light source;
a translucent joining member disposed between the covering member and the light reflecting member and covering a part of a side surface of the light source;
A light-emitting module in which an outer edge of the light source is arranged outside the wavelength conversion member in plan view.

According to the present disclosure, it is possible to provide a manufacturing method capable of easily manufacturing a light-emitting module with reduced color shift and a light-emitting module with reduced color shift.

It is a schematic sectional drawing which shows the manufacturing method of the light emitting module of one Embodiment of this invention. It is a schematic sectional drawing which shows the manufacturing method of the light emitting module of one Embodiment of this invention. It is a schematic sectional drawing which shows the manufacturing method of the light emitting module of one Embodiment of this invention. It is a schematic sectional drawing which shows the manufacturing method of the light emitting module of one Embodiment of this invention. It is a schematic sectional drawing which shows the manufacturing method of the light emitting module of one Embodiment of this invention. It is a schematic sectional drawing which shows the manufacturing method of the light emitting module of one Embodiment of this invention. It is a schematic sectional drawing which shows the manufacturing method of the light emitting module of one Embodiment of this invention. It is a schematic sectional drawing which shows the manufacturing method of the light emitting module of one Embodiment of this invention. It is a schematic sectional drawing which shows the manufacturing method of the light source of a light emitting module. It is a schematic sectional drawing which shows the manufacturing method of the light source of a light emitting module. It is a schematic sectional drawing which shows the manufacturing method of the light source of a light emitting module. It is a schematic sectional drawing which shows the manufacturing method of the light source of a light emitting module. It is a schematic sectional drawing which shows the manufacturing method of the light source of a light emitting module. 1 is a schematic cross-sectional view of part of a light emitting module according to an embodiment of the invention; FIG. FIG. 4 is a schematic cross-sectional view of part of a light emitting module according to another embodiment of the invention; FIG. 5 is a schematic cross-sectional view of part of a light emitting module of yet another embodiment of the invention; 1 is a schematic plan view of a light emitting module according to one embodiment of the present invention; FIG. 1 is an exploded perspective view showing a liquid crystal display device using a light emitting module of the present invention; FIG.

The present invention will now be described in detail with reference to the drawings. When the following description uses terms indicating a specific direction or position where necessary (e.g., "upper", "lower" and other terms that include those terms), refer to the drawings for the use of those terms. The meaning of these terms is not intended to limit the technical scope of the present invention. For example, the surface of each member arranged on the light emitting surface side of the light emitting module may be referred to as the first principal surface, first surface or top surface, and the surface opposite to the light emitting surface may be referred to as the second principal surface, second surface or bottom surface. be. Parts with the same reference numbers that appear in multiple drawings indicate the same or equivalent parts or members.
Moreover, 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. Furthermore, 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 illustrative. It is intended. The contents described in one embodiment and example can also be applied to other embodiments and examples. The sizes, positional relationships, etc. of members shown in the drawings may be exaggerated for clarity of explanation.

[Method for producing light-emitting module]
An example of a light-emitting module 20 obtained by a method for manufacturing a light-emitting module according to an embodiment of the present disclosure includes a light guide plate 10, a wavelength converting member 11, a light source 25, and a light reflecting member 15, as shown in FIG. 3A. Prepare.

The light guide plate 10 includes a first main surface 10U and a second main surface 10B, as shown in FIG. 1A. The second main surface 10B has a recess 10R. The wavelength conversion member 11 is arranged inside the recess 10R. The light source 25 includes the light emitting element 12 and the covering member 13 covering the side surface of the light emitting element 12 . The light source 25 is joined to the wavelength conversion member 11 . The light reflecting member 15 seals the second main surface 10B of the light guide plate 10 and the light source 25 .

A method for manufacturing a light-emitting module according to an embodiment of the present disclosure mainly includes the following steps.
A light guide plate 10 including a first main surface 10U that serves as a light emitting surface and a second main surface 10B opposite to the first main surface 10U and having a plurality of recesses 10R is prepared. process and
A step of preparing the wavelength conversion member 11 having an area smaller than the area of the recess 10R in plan view;
covering the side surface of the light emitting element 12 comprising a semiconductor laminate having a first surface 12U and a second surface opposite to the first surface 12U and electrodes 12n and 12p arranged on the second surface, and the light emitting element 12; preparing a light source 25 comprising a covering member 13 exposing the electrodes 12n, 12p;
placing the wavelength conversion member 11 in the recess 10R;
A step of fixing the light source 25 on the wavelength conversion member 11 with the first surface 12U of the semiconductor laminate in the light emitting element 12 facing each other;
and a step of sealing the light source 25 and the second main surface 10B of the light guide plate 10 with the light reflecting member 15a.

In the method for manufacturing a light-emitting module according to the present embodiment, since the wavelength conversion member 11 and the light source 25 are arranged with respect to the plurality of concave portions 10R of the light guide plate 10, the wavelength conversion member 11 and the light source 25 can be easily positioned. can. Moreover, since the light source 25 includes the light emitting element 12 and the covering member 13, it is easier to handle than when only the light emitting element 12 is used, and the alignment accuracy can be improved. As a result, the light from the light source 25 can be made uniform, and a light-emitting module with little color shift can be obtained.

In addition to the above-described steps, the method for manufacturing a light-emitting module according to the embodiment includes, for example, a step of disposing the translucent member 14 in the recess 10R (FIG. 1B), sealing with the light-reflecting member 15, and then forming the electrode of the light source 25. from the light reflecting member 15 (FIG. 1F), forming a wiring layer 16 connected to the electrodes (FIG. 1G), and cutting the light reflecting member 15 and the light guide plate 10 after forming the wiring layer 16. (FIG. 1H).

(Step of preparing light guide plate)
First, as shown in FIG. 1A, a light guide plate 10 is prepared.

(Light guide plate 10)
The light guide plate 10 is a translucent member that receives light from a light source and emits planar light. The light guide plate 10 has a first main surface 10U that serves as a light emitting surface, and a second main surface 10B opposite to the first main surface 10U.

A plurality of recesses 10R are arranged on the second main surface 10B. The recess 10R has a bottom surface and side surfaces. The size of the concave portion 10R in plan view can be, for example, a maximum length of 0.05 mm to 10 mm, preferably 0.1 mm to 1 mm. The depth can be from 0.05 mm to 4 mm, preferably from 0.1 mm to 1 mm. The shape of the concave portion 10R in plan view may be polygonal such as a quadrangle or a pentagon, a circle, or an ellipse. The planar shape of the recess 10R is preferably square or circular. Also, the side surface of the recess 10R can be a surface perpendicular to the first principal surface or the second principal surface, or a slanted surface. Also, the bottom surface of the recess 10R can be a surface parallel to the first main surface or the second main surface.

The plurality of recesses 10R can be arranged at regular intervals in the row direction or the column direction. Alternatively, the plurality of recesses 10R can be arranged at uneven intervals in the row direction or column direction. For example, the plurality of recesses 10R can be arranged so that the intervals become wider from the center of the light guide plate 10 toward the periphery.

The arrangement pitch (distance between the two closest recesses) of the recesses 10R in the light guide plate 10 takes into consideration the size of the recesses 10R, the size and characteristics of the light source to be used, the luminance to be obtained in the light guide plate, and the like. can be adjusted accordingly. For example, the arrangement pitch of the concave portions 10R may be 5 to 20 times the length of one side of the light source. Specifically, it can be 0.05 mm to 20 mm, preferably 2 mm to 12 mm, and more preferably 1 mm to 10 mm.

The planar shape of the light guide plate 10 can be, for example, polygonal, circular, or the like. The size of the light guide plate 10 can be, for example, 1 cm to 200 cm on a side, preferably 3 cm to 30 cm. The thickness of the light guide plate 10 can be 0.1 mm to 5 mm, preferably 0.5 mm to 3 mm.

The light guide plate 10 is made of thermoplastic resin such as acrylic, polycarbonate, cyclic polyolefin, polyethylene terephthalate or polyester, resin material such as thermosetting resin such as epoxy resin or silicone resin, or optically transparent material such as glass. can be formed by In particular, a thermoplastic resin material is preferable from the viewpoint that it can be efficiently manufactured by injection molding. In particular, polycarbonate and polyethylene terephthalate, which have high transparency and are inexpensive, are preferred.

The light guide plate 10 can be prepared by molding, for example, by injection molding, transfer molding, or the like. It is preferable that the concave portion 10R of the light guide plate 10 is formed at the same time when the light guide plate 10 is molded. As a result, it is possible to reduce misalignment of the concave portion 10R. The light guide plate 10 can be prepared by purchase. Alternatively, it is possible to purchase or mold a flat plate-like light guide plate that does not have recesses, and to prepare it through processing steps such as forming recesses.

The light guide plate 10 may be formed of a single layer, or may be formed by laminating a plurality of translucent layers. When a plurality of light-transmitting layers are laminated, the entire surface of each light-transmitting layer can be bonded with an adhesive or an adhesive sheet. Alternatively, a layer having a different refractive index, such as an air layer, may be provided between the translucent layers. As a result, the light can be diffused more easily, and the light-emitting module can have reduced luminance unevenness. Such a structure can be realized, for example, by providing a spacer between arbitrary light-transmitting layers to separate them and providing an air layer.

The light guide plate 10 may include an optical function portion 10F having a reflecting or diffusing function or the like on the first main surface 10U.

The optical function part 10</b>F preferably has a function of spreading light within the plane of the light guide plate 10 and averaging the emission intensity within the plane of the light guide plate 10 . For example, the optical function part 10F can be a recess provided on the first main surface 10U side. The optical function part 10F includes, for example, a concavity such as a polygonal pyramid shape such as a conical shape, a square pyramid shape, a hexagonal pyramid shape, etc., and a polypyramidal truncated recess such as a truncated cone shape, a square pyramid shape, or a hexagonal truncated pyramid shape. be done.

By arranging a material (for example, air) having a different refractive index from that of the light guide plate 10 inside these recesses, the light irradiated to the interface with the side surfaces (inclined surfaces) of the recesses is reflected in the lateral direction of the light source 25. can be made Also, a light-reflecting material (for example, light-reflecting metal, white resin, dielectric film) or the like may be placed in the recess.

The side surface (inclined surface) of the recess that functions as the optical function portion 10F may be straight or curved in a cross-sectional view. The side surface of the recess may be curved inwardly convex or curved inwardly when viewed in cross section. Also, the side surface of the recess may have two or more curved surfaces with different curvatures in a cross-sectional view. The light-reflecting material described above can be arranged to cover part or all of the sides of the recess.

The optical function portion 10F is preferably provided at a position overlapping the recess 10R in plan view. It is preferable that the center of the optical function portion 10F and the center of the recess 10R match in plan view.

Concavities and convexities may be formed on the first main surface 10U and the second main surface 10B of the light guide plate 10 .

(Step of preparing wavelength conversion member)
As shown in FIG. 1A, a wavelength conversion member 11 is prepared. The number of wavelength conversion members 11 equal to or greater than the number of recesses of the light guide plate is prepared. The wavelength conversion member 11 is prepared using a resin material or a material containing glass and a phosphor, which will be described later, by molding it into a plate shape by a method such as injection molding, transfer molding, or printing, and then cutting the plate. be able to. Moreover, when forming the wavelength conversion member of a small piece beforehand, a cutting process can be abbreviate|omitted. Furthermore, a plate-shaped resin material or glass that does not contain a phosphor or that contains a phosphor is prepared, and a liquid resin material containing a phosphor is printed or sprayed on one or more surfaces of the plate-shaped member. A wavelength conversion member can be prepared by forming a phosphor layer in the above. Alternatively, the wavelength conversion member can be prepared by preparing a plate-shaped resin material or glass that does not contain a fluorescent substance or that contains a fluorescent substance and adheres the fluorescent substance to the surface of the plate-shaped member by electrophoresis. can. Moreover, you may prepare by purchasing and cutting|disconnecting a plate-shaped wavelength conversion member. Alternatively, it may be prepared by purchasing a small piece of wavelength conversion member.

(Wavelength conversion member)
The wavelength conversion member 11 is a member capable of converting the wavelength of light emitted from the light emitting element, and includes, for example, a phosphor or a translucent material containing a phosphor. The wavelength conversion member 11 can be made of epoxy resin, silicone resin, a resin mixture thereof, or a translucent material such as glass. From the viewpoint of light resistance and moldability of the wavelength conversion member 11, a silicone resin is preferable. A translucent material forming the wavelength conversion member 11 is preferably a material having a higher refractive index than the material of the light guide plate 10 .

Phosphors contained in the wavelength conversion member 11 include yttrium _- aluminum-garnet-based phosphors (for example, Y3(Al,Ga) _5O12 :Ce), lutetium-aluminum-garnet-based phosphors (for example, _{Lu3 (} Al , Ga) ₅ O ₁₂ :Ce), terbium-aluminum-garnet-based phosphors (for example, Tb ₃ (Al, Ga) ₅ O ₁₂ :Ce)-based phosphors, silicate-based phosphors (for example, (Ba, Sr) ₂ SiO ₄ :Eu), and chlorosilicate _- based phosphors (for example, _{Ca8Mg (} SiO4) _4Cl2 :Eu). Furthermore, as nitride phosphors, β-sialon phosphors (eg Si ₆ -zAlzOzN 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) phosphor (for example, (Sr _, Ca) AlSiN ₃ :Eu). at least one element selected from the group consisting of Sr and Ba; Mb is at least one element selected from the group consisting of Li, Na and K; x, y and z are each 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 MnaF ₆ ] (wherein the above general formula (II), A is K, Li, is at least one selected from the group consisting of 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< satisfies 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)). In particular, a plurality of types of wavelength conversion members are used in one wavelength conversion member 11, and more preferably, the wavelength conversion member 11 is composed of a β-sialon phosphor that emits greenish light and a KSF phosphor that emits reddish light. The color reproduction range of the light-emitting module can be widened by including a fluoride-based phosphor such as

The phosphor and/or translucent material that constitute the wavelength conversion member 11 can be appropriately selected depending on the desired chromaticity and the like, and the amounts thereof can be adjusted. When the translucent material contains a phosphor, the phosphor may be distributed substantially uniformly in the translucent material, or may be unevenly distributed. Also, the wavelength conversion member may be formed by stacking a plurality of layers containing the same or different phosphors at the same or different concentrations.

In the wavelength conversion member 11, a layer containing a diffusing material may be arranged in the same layer as the layer containing the phosphor or in a different layer. Examples of diffusion materials include SiO ₂ and TiO ₂ .

It is preferable to prepare a plurality of wavelength conversion members 11 as plate-shaped bodies of arbitrary sizes. The planar shape of the wavelength conversion member 11 can be polygonal, circular, or the like. It is preferable that the planar shape of the wavelength conversion member 11 is a quadrangle. The size of the wavelength converting member 11 is preferably smaller than the area of the concave portion 10R of the light guide plate 10 in plan view. In other words, it is preferable that the entire outer edge of the wavelength conversion member 11 is sized to fit within the outer edge of the concave portion 10</b>R of the light guide plate 10 . In particular, the area of the wavelength converting member 11 in plan view is preferably 99% to 60%, more preferably 95% to 80%, of the area of the concave portion 10R of the light guide plate 10 in plan view.

The cross-sectional shape of the wavelength conversion member 11 can be such that the wavelength conversion member 11 can be accommodated in the concave portion 10</b>R of the light guide plate 10 . For example, the cross-sectional shape of the wavelength conversion member 11 may be trapezoidal, semicircular, or the like with a narrow or wide upper surface. In particular, the cross-sectional shape of the wavelength conversion member 11 is preferably quadrangular. The thickness of the wavelength conversion member 11 can be the same thickness as the depth of the recess 10R of the light guide plate 10 or a thickness smaller than that.

The wavelength conversion member 11 may have irregularities formed on its surface.

(Step of preparing light source)
As shown in FIG. 1A, a light source 25 is provided. As with the wavelength conversion member 11, the number of the light sources 25 equal to or greater than the number of the concave portions 10R of the light guide plate 10 is prepared. Light source 25 includes light emitting element 12 and covering member 13 .

In the light emitting module shown in FIGS. 3A and 3B, the width of the light source 25 is larger than the width of the wavelength conversion member 11, that is, the outer edge of the light source 25 is arranged outside the wavelength conversion member 11 in plan view. is shown. Also, the width of the light source 25 may be the same as the width of the wavelength conversion member 11, or the width of the light source 25 may be smaller than the width of the wavelength conversion member 11 as shown in FIG. 3C.

(light emitting element)
The light emitting element 12 includes a semiconductor laminate having a first surface 12U and a second surface opposite to the first surface, and electrodes 12n and 12p arranged on the second surface. A known semiconductor light emitting device can be used as the light emitting device. For example, the semiconductor laminate includes a translucent substrate such as sapphire and a semiconductor layer laminated on the translucent substrate. The semiconductor layers include a light emitting layer, and an n-type semiconductor layer and a p-type semiconductor layer sandwiching the light emitting layer. Electrodes 12n and 12p are electrically connected to the n-type semiconductor layer and the p-type semiconductor layer, respectively. Both of the electrodes 12n and 12p are arranged on the second surface side of the semiconductor laminate of the light emitting element.

The plurality of light sources 25 can include light emitting elements that emit light of different colors. Alternatively, multiple light sources 25 may comprise light emitting elements that emit light of the same color. For example, as a light-emitting element that emits blue and green light, a nitride-based semiconductor (In _x Al _y Ga _1-x-y N, 0≦X, 0≦Y, X+Y≦1) or GaP is used for light emission. element can be used. Furthermore, semiconductor light-emitting elements made of materials other than these can also be used. Various emission wavelengths can be selected depending on the material of the semiconductor layer and its crystallinity. The composition, emission color, size, number, and the like of the light-emitting elements to be used can be appropriately selected according to the purpose.

One light source 25 can comprise one or more light emitting elements 12 . One light source 25 can comprise light emitting elements that emit light of the same color. Alternatively, one light source 25 can comprise lights that emit light of different colors. In that case, a light-emitting element that emits red light can be used in combination with a light-emitting element that emits blue or green light. As a light-emitting element that emits red light, a light-emitting element containing a semiconductor such as GaAlAs or AlInGaP can be used.

The length, width and height of the light emitting element 12 can be arbitrarily set. The vertical and horizontal dimensions in plan view are preferably 1000 μm or less, more preferably 500 μm or less. By using such a light-emitting element, for example, a high-definition image can be realized when local dimming is performed on a liquid crystal display device. In addition, since the light source 25 can be procured at a low cost, the light emitting module 20 can be made at a low cost.

(coating member)
The covering member 13 constitutes a part of the light source and covers the side surface of the semiconductor laminate of the light emitting element 12 . Furthermore, the covering member 13 covers the second surface of the semiconductor laminate so that at least part of the surface of the electrodes 12n and 12p of the light emitting element 12 is exposed. The covering member 13 covers at least part of the side surfaces of the electrodes 12n and 12p.

A light reflective material can be used for the covering member 13 . The reflectance of the covering member 13 may be, for example, 60% or more, or 90% or more, with respect to the light emitted from the light emitting element. For the light-reflecting covering member 13, for example, a thermosetting resin, a thermoplastic resin, or the like containing a light-reflecting substance can be used as a resin material. Specifically, modified epoxy resins such as epoxy resins, silicone resins, silicone-modified epoxy resins, modified silicone resins such as epoxy-modified silicone resins, unsaturated polyesters, saturated polyesters, polyimide resins, modified polyimide resins, polyphthalamide (PPA) ), polycarbonate, polyphenylene sulfide (PPS), liquid crystal polymer (LCP), ABS resin, phenol resin, acrylic resin, PBT resin, and the like. In particular, it is preferable to use a thermosetting resin such as an epoxy resin, a silicone resin, or a modified silicone resin. Light-reflecting substances include titanium oxide, silicon oxide, zirconium oxide, potassium titanate, aluminum oxide, zinc oxide, aluminum nitride, boron nitride, and mullite. The light-reflecting substance can be contained, for example, in an amount of 20% to 60% by weight with respect to the total weight of the resin.

When the light source 25 is the same size as or smaller than the wavelength conversion member 11 in plan view, the covering member 13 may be made of a translucent material. That is, as shown in FIG. 3B, when the entire light source 25 overlaps the wavelength conversion member 11 in plan view, the light from the light emitting element is transmitted from the first surface of the semiconductor laminate and the covering member to the wavelength conversion member 11. is incident. The transmittance of the covering member 13 can be, for example, 95% or more with respect to the light emitted from the light emitting element.

The covering member 13 can cover all or part of the side surface of the light emitting element 12 in contact therewith. As shown in FIG. 3A and the like, the covering member 13 can contact and cover the entire side surface of the light emitting element 12 .

3B, the covering member 13 may cover a part of the side surface of the light emitting element 12 via the translucent bonding member 19. As shown in FIG. In this case, the translucent bonding member 19 preferably covers part of the side surface of the light emitting element 12 so that the outer side surface is gently concave with respect to the side surface of the light emitting element 12, for example. In other words, the cross-sectional shape of the translucent bonding member 19 should be such that the width is wide on the first surface side of the semiconductor laminate on the side surface of the light emitting element 12 and gradually narrows toward the second surface. is preferred.

The first surface of the semiconductor laminate of the light emitting element may be covered with a translucent thin film. As the light-transmitting thin film, for example, the same material as the light-transmitting material included in the wavelength conversion member can be used.

Such a light source 25 can be purchased and prepared. Alternatively, the light source 25 can be prepared through at least one process such as the process of forming the light emitting element 12 and the process of covering the light emitting element 12 with the covering member 13 . 2A-2C show an example of a method of manufacturing the light source 25. FIG.

(Step of fixing the light emitting element)
First, as shown in FIG. 2A, the first surface (light emitting surface) side of the semiconductor laminate in the light emitting element 12 described above is fixed onto the base material 18 with a translucent bonding material 19a. The translucent bonding material 19a used here preferably has translucency, for example, a resin that transmits 60% or more of the light emitted from the light emitting element, or a resin that transmits 70% or more of the light. As the translucent bonding material, for example, a thermosetting resin such as an epoxy resin, a silicone resin, or a modified silicone resin can be used.

The translucent bonding material 19a can be arranged on the base material 18 by potting, printing, or the like. The first surface of the semiconductor laminate in the light emitting element 12 is placed on the translucent bonding material 19a. The translucent bonding material 19a is heated and cured. In FIG. 2A , the translucent bonding material 19 a extends over the side surface of the light emitting element 12 and is arranged to partially cover the side surface of the light emitting element 12 . However, as shown in FIG. 1A, the translucent bonding material 19a does not have to be arranged on the side surface of the light emitting element 12 . When the translucent bonding material 19a is arranged on the side surface of the light emitting element 12, the light emitted in the side direction of the light emitting element 12 can be efficiently extracted in the direction of the wavelength conversion member 11 and the light guide plate 10. .

The base material 18 may be formed of any material such as an insulating material or a conductive material having rigidity or flexibility. For example, the base material 18 may be a resin material, a metal material, or the like. The base material 18 is preferably a resin sheet or the like having one surface coated with a translucent bonding material from the viewpoint of being inexpensive and easy to remove.

(Step of covering the light emitting element)
Next, as shown in FIG. 2B, a covering member 13a is formed so as to cover all of the light emitting elements 12 of the light emitting elements 12 fixed on the substrate 18. Next, as shown in FIG. Thereafter, as shown in FIG. 2C, a portion of the covering member 13a is removed to expose the electrodes 12n and 12p of the light emitting element 12. Then, as shown in FIG. At least a part of the upper surface of the electrodes 12n and 12p should be exposed. A part of the covering member 13a can be removed by grinding, etching, or the like. When the covering member 13 is formed so as not to cover the upper surfaces of the electrodes 12n and 12p, the step of removing part of the covering member 13a can be omitted.

(Step of removing base material)
After covering the side surface of the light emitting element 12 with the covering member 13, the base material 18 is removed from the light emitting element 12 as shown in FIG. 2D.
After removing the substrate 18, the covering member 13 is cut to include at least one light emitting element 12, as shown in FIG. 2E. Alternatively, the base material 18 may be removed after the covering member 13 is cut on the base material 18 .
By such a method, the light source 25 including the light emitting element 12 and the covering member 13 can be formed.

(Step of arranging wavelength conversion member in concave portion)
A wavelength converting member 11 is arranged in the concave portion 10</b>R of the light guide plate 10 . The wavelength converting member 11 is preferably fixed by, for example, a translucent member 14 . Therefore, as shown in FIG. 1B, first, the translucent member 14 is arranged in the concave portion 10R of the light guide plate 10 . The translucent member 14 may be provided on the light source 25 instead of inside the recess. Alternatively, the translucent member 14 may be provided both inside the recess 10</b>R and above the light source 25 .

As the translucent member 14, for example, a resin that transmits 60% or more of the light emitted from the light emitting element or a resin that transmits 70% or more of the light is preferable. Examples of the translucent member 14 include epoxy resins, silicone resins, and mixed resins thereof. It is preferable to use a silicone resin for the translucent member 14 in consideration of translucency, light resistance, and the like. The translucent member 14 is preferably arranged in the recess 10R with a volume of 50% or more, 60% or more, 95% or less, or 90% or less of the recess 10R. Potting, transfer, spraying, etc., can be used as a method for disposing the translucent member 14 .

Next, as shown in FIG. 1C, the wavelength converting member 11 is placed inside the recess 10R in which the translucent member 14 is placed. The wavelength conversion member 11 is fixed to the bottom surface of the recess 10R with the translucent member 14 interposed therebetween. Part or all of the wavelength conversion member 11 is preferably covered with the translucent member 14 in the recess 10R. A part of the translucent member 14 may extend on the second main surface outside the recess 10R.

(Step of fixing the light source)
Subsequently, as shown in FIG. 1D, the first surface of the semiconductor laminate of the light emitting element 12 in the light source 25 is fixed on the wavelength conversion member 11 fixed in the recess 10R. The light source 25 is fixed on the wavelength conversion member 11 using as the translucent bonding member described above. Thereby, the light source 25 can be fixed on the wavelength conversion member 11 as shown in FIG. 3A.

Further, as shown in FIG. 3B , the translucent bonding member 19 may cover at least a portion of the upper surface of the translucent member 14 . In that case, the translucent joining member 19 may crawl up the side surface of the light source 25 . Specifically, the translucent bonding member 19 crawls up the side surface of the covering member 13 of the light source 25 . In this case, the translucent bonding member 19 is arranged so as to be in contact with the wavelength conversion member 11 and the translucent member 14 . The translucent bonding member 19 can cover at least a portion of each side surface of the covering member 13 of the light source 25 .

After fixing the wavelength converting member 11 in the concave portion 10R of the light guide plate 10 in this way, by fixing the light source 25 on the wavelength converting member 11, the optical axis of the light source 25 is aligned with the concave portion 10R and/or the wavelength converting portion. It can be arranged at a desired position on the member 11 . As a result, color misregistration can be effectively prevented.

The arrangement pitch of the light sources 25 can be the same pitch as the positions of the concave portions 10R of the light guide plate 10 described above. Alternatively, according to the position of the recesses 10R on the first surface or the second surface of the light guide plate, they can be arranged at an arrangement pitch different from the pitch of the recesses. For example, the distance between light sources 25 can be 0.05 mm to 20 mm, preferably 2 mm to 12 mm, more preferably 1 mm to 10 mm. With such an arrangement pitch, it is possible to ensure uniform brightness in the plane of the light guide plate 10 .

(Step of sealing with a light reflecting member)
As shown in FIG. 1E, the light source 25 and the second main surface 10B of the light guide plate 10 are sealed with the light reflecting member 15a. The second main surface 10B of the light guide plate 10 is also sealed with the light reflecting member 15a. Here, the light reflecting member 15a is formed so as to also cover the upper surfaces of the electrodes 12n and 12p of the light source 25. As shown in FIG.

Next, as shown in FIG. 1F, part of the light reflecting member 15a is removed to expose the surfaces of the electrodes 12n and 12p of the light emitting element 12. Next, as shown in FIG. If the light reflecting member 15 is formed so as not to fill the upper surface of the electrode in advance, the step of removing part of the light reflecting member 15 can be omitted. The light reflecting member 15 and the electrodes 12n and 12p are preferably flush with each other.

The light reflecting members 15 and 15a can be made of a resin material, a light reflecting substance, or the like. For example, a silicone resin mixed with titanium oxide can be mentioned. The light reflecting member 15 can be formed by transfer molding, potting, printing, spraying, or the like, for example. Partial removal in the thickness direction can be performed by methods known in the art, such as grinding and etching.

(Step of forming wiring layer)
Next, a wiring layer 16 electrically connected to the electrodes 12n and 12p of the light emitting element 12 is formed. For example, a metal film is formed on substantially the entire surface including the upper surfaces of the electrodes 12n and 12p and the upper surface of the light reflecting member 15 by sputtering or the like. After that, the wiring layer 16 having a desired shape can be formed by removing part of the metal film by irradiating it with a laser beam. Moreover, the wiring layer 16 having a desired shape can be formed by printing the conductive paste using a mask or the like.

Examples of the wiring layer include single-layer films or laminated films of metals such as Au, Pt, Pd, Rh, Ni, W, Mo, Cr, and Ti, or alloys thereof. Specifically, metal films of Cu/Ni/Au from the light guide plate 10 side can be used.

Subsequently, as shown in FIG. 1G, the wiring layer 16 and the wiring layer of the wiring board 17 prepared separately are pressure-bonded to be joined to electrically connect the wiring layer 16 and the wiring layer of the wiring board 17. . Thereby, the wiring board 17 and the light source 25 can be electrically connected.

The base material of the wiring board 17 can be formed using, for example, ceramics such as aluminum nitride, resin, or the like. 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. The wiring board 17 may be a rigid board or a flexible board.

The wiring layer 16 can be formed so that the plurality of light sources 25 are individually lit. Further, the wiring layer 16 can be formed on the light guide plate 10 so that a plurality of light sources 25 are turned on at the same time to form one light emitting area. For example, the light sources 25 arranged in a matrix form are divided into four light source groups arranged in two rows and two columns, and a wiring layer that emits light is formed for each group, so that a light emitting module capable of local dimming can be obtained. .

(Step of cutting the light guide plate)
Optionally, the light guide plate 10 can be cut to include at least one or more light sources 25, as shown in FIG. 1H. Also, if the light reflecting member 15 or the wiring board 17 is present at the cutting position, these can be cut at the same time as the light guide plate 10 is cut. Further, when the light guide plate 10 having a predetermined shape and size is prepared in advance, the step of cutting the light guide plate 10 can be omitted.

[Light-emitting module]
The light emitting module 20 of this embodiment is shown in FIG. 3B.
The light emitting module 20 is
a light guide plate 10 having a first principal surface 10U and a second principal surface 10B, and having a concave portion 10R in the second principal surface 10B;
a wavelength conversion member 11 arranged in a recess 10R on the second main surface 10B side of the light guide plate 10;
a light source 25 joined to the wavelength conversion member 11, the light source 25 including the light emitting element 12 and the covering member 13 covering the side surface of the light emitting element 12;
a light reflecting member 15 that seals the second main surface 10B of the light guide plate 10 and the light source 25;
A translucent member (second translucent member 14 a ) is provided between the light source 25 and the light reflecting member 15 and covers a part of the side surface of the light source 25 .
In the light emitting module 20, the outer edge of the light source 25 is arranged on the outer edge of the wavelength conversion member 11 in plan view. Specifically, the outer edge of the covering member 13 is arranged outside the wavelength conversion member 11 .

The light emitting module 20 further includes wiring layers 16 connected to the electrodes 12 n and 12 p of the light source 25 .

One light guide plate 10 has a plurality of recesses 10R, and one wavelength conversion member 11 and one light source 25 are arranged in each of the recesses 10R.

With the light-emitting module 20 having such a configuration, the light from the light-emitting elements can be spread more uniformly in the lateral direction. In a plan view, the outer edge of the covering member is arranged outside the wavelength conversion member, so that the light that has entered the wavelength conversion member can be efficiently made to enter the light guide plate. Therefore, it is possible to reduce the color shift of the light emitting module.

The light emitting module 20 can be used, for example, in a liquid crystal display device 30, as shown in FIG. 4B. The liquid crystal display device 30 includes a liquid crystal panel 21, lens sheets 22 and 23, a diffusion sheet 24, and a light emitting module 20 in order from the top. The liquid crystal display device 30 is a so-called direct type liquid crystal display device in which the light emitting module 20 is arranged below the liquid crystal panel 21 . The liquid crystal display device 30 irradiates the liquid crystal panel 21 with light emitted from the light emitting module 20 . The liquid crystal display device 30 may further include members such as polarizing films and color filters.

REFERENCE SIGNS LIST 10 light guide plate 10B second main surface 10F, 10F1 optical function portion 10R recess 10U first main surface 11 wavelength conversion member 12 light emitting element 12n electrode 12p electrode 12U first surface 13, 13a coating member 14 translucent member 14a second translucent Optical member 15, 15a Light reflecting member 16 Wiring layer 17 Wiring board 18 Base material 19 Translucent bonding member 19a Translucent bonding material 20 Light emitting module 21 Liquid crystal panel 22, 23 Lens sheet 24 Diffusion sheet 25 Light source 30 Liquid crystal display device

Claims (7)

preparing a light guide plate having a first main surface serving as a light emitting surface and a second main surface opposite to the first main surface and having a plurality of recesses;
preparing a wavelength conversion member having an area smaller than the area of the recess in plan view;
A light-emitting element comprising a semiconductor laminate having a first surface and a second surface opposite to the first surface and an electrode disposed on the second surface; and covering a side surface of the light-emitting element and exposing the electrode. providing a light source comprising a covering member for
disposing a translucent member and the wavelength conversion member in the recess so as to cover the side surface of the wavelength conversion member;
a step of fixing the light source on the wavelength conversion member with the first surface side of the semiconductor laminate of the light emitting element facing each other;
and sealing the light source and the second main surface of the light guide plate with a light reflecting member. 2. The method of manufacturing a light-emitting module according to claim 1 , further comprising, after sealing with the light-reflecting member, exposing the electrode of the light-emitting element from the light-reflecting member and forming a wiring layer connected to the electrode. . 3. The method of manufacturing a light-emitting module according to claim 2 , further comprising cutting the light reflecting member and the light guide plate after forming the wiring layer. The step of preparing the light emitting device includes:
a step of fixing the first surface of the semiconductor laminate in the light emitting device onto a base material with a translucent bonding material;
covering the side surface of the light emitting element with the covering member so that the electrode is exposed from the covering member;
The method of manufacturing a light-emitting module according to any one of claims 1 to 3 , further comprising a step of removing the base material from the light-emitting element. a light guide plate having a first main surface serving as a light emitting surface and a second main surface opposite to the first main surface and having a plurality of recesses;
a wavelength conversion member disposed within the recess of the light guide plate;
a light source joined to the wavelength conversion member, the light source including a light emitting element and a covering member covering the side surface of the light emitting element;
a light reflecting member that seals the second main surface of the light guide plate and the light source;
a translucent joining member disposed between the covering member and the light reflecting member and covering a part of a side surface of the light source;
A light-emitting module in which an outer edge of the light source is arranged outside the wavelength conversion member in plan view. 6. The light emitting module according to claim 5 , further comprising a wiring layer connected to the electrodes of said light source. one said light guide plate has a plurality of recesses,
in each of the recesses,
7. The light-emitting module according to claim 5 , wherein one said wavelength conversion member and one said light-emitting element are arranged.

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