KR101831778B1 - Resin Composition For Cover Bottom of Backlight Unit And Backlight Unit Including The Same - Google Patents

Abstract

The present invention provides a backlight unit including a base resin, a resin composition for a backlight unit cover bottom including a bead mixed in the base resin and having a hollow therein, and a cover bottom made of the resin composition, The light guide plate and the white reflection sheet are removed to reduce the manufacturing cost, lightness and thinness are achieved, and the light reflectance and the uniformity of the outgoing light are improved.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a resin composition for a back cover unit and a backlight unit,

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a backlight unit technology field, and more particularly, to a backlight unit including a resin composition of a cover bottom and a cover bottom made using the resin composition.

Description of the Related Art [0002] A liquid crystal display (LCD) is a widely used flat panel display (FPD) and requires light because it displays an image using a liquid crystal which is a light-receiving element that can not emit light itself. Therefore, the liquid crystal display device receives light from the backlight unit attached to the rear surface of the liquid crystal display panel and displays an image.

The backlight unit is classified into an edge type and a direct type according to the arrangement of the light sources. The direct-type backlight unit is configured such that a plurality of light sources are disposed on the back surface of the liquid crystal display panel, and light is supplied to the front liquid crystal display panel. The edge type backlight unit has a light guide plate on a back surface of a liquid crystal display panel and a light source on a side surface of the light guide plate to supply a surface light source to the liquid crystal display panel. In the case of such an edge type backlight unit, much research has been conducted to change the structure of the light guide plate and to smoothly supply light to the liquid crystal display panel, as disclosed in Korean Patent Laid-open No. 10-2011-0021193.

1 schematically shows a conventional edge type backlight unit structure.

1, the conventional edge type backlight unit includes a light guide plate 40, a reflector 50 disposed below the light guide plate 40, an LED module array 30 disposed on a side surface of the light guide plate 40, An optical sheet 70 disposed on the upper side of the light guide plate 40, and a metal chassis 10 accommodating the above-described components. The light guide plate 40 converts the light emitted from the LED module array 30 into a planar light source and supplies the planar light source to the liquid crystal display panel. The light guide plate 40 is one of the essential components of the conventional backlight unit. However, the backlight unit including such a light guide plate 40 has problems in that light loss occurs in the light guide plate 40, power consumption increases due to the occurrence of light loss, and the warping of the light guide plate 40 occurs due to its own weight There was a problem that occurred.

In addition, the conventional edge type backlight unit has a problem that the weight of the backlight unit itself increases because the components are housed using a chassis made of a metal material, that is, a metal chassis 10, A white reflective sheet must be additionally formed on the surface of the reflective sheet.

Korean Patent Laid-Open No. 10-2011-0021193 (Published March 4, 2011)

Disclosure of Invention Technical Problem [8] Accordingly, the present invention has been made in view of the above problems, and provides a resin composition for a backlight unit cover bottom comprising a base resin, It is an object of the present invention to provide a backlight unit including a cover bottom to reduce the manufacturing cost by eliminating the light guide plate and the white reflection sheet, which are conventionally used, and to improve the light reflectance and uniformity of light output while realizing weight reduction and thinness.

In order to solve the above problems, the present invention provides a backlight unit cover bottom resin composition comprising: a base resin; And a bead mixed and formed in the base resin and having a hollow therein.

In the resin composition for a backlight unit cover bottom of the present invention, the beads may be at least one of glass beads, acrylic beads and amide beads.

In the resin composition for a backlight unit cover bottom of the present invention, the content of the beads in the resin composition may be 10% by weight to 30% by weight.

In the resin composition for a backlight unit cover bottom of the present invention, the diameter of the beads may be in the range of 0.55 to 135 mu m.

The resin composition for a backlight unit cover bottom of the present invention may further comprise an inorganic material mixed and formed in the base resin.

In the resin composition for a backlight unit cover bottom of the present invention, the inorganic material may include at least one of BaSO 4, TiO 2, and CaCO 3, and the shape may be spherical. The diameter of the inorganic material may be in the range of 0.11 to 2 mu m.

In the resin composition for a backlight unit cover bottom of the present invention, the base resin may be made of a thermoplastic resin, and may include a polycarbonate resin, a polymethylmethacrylate resin, a polypropylene resin, a polyethylene Polyethylene) resin.

The resin composition for a backlight unit cover bottom of the present invention may further comprise an additive mixedly formed in the base resin, wherein the additive is selected from the group consisting of a fluorescent brightener, a crosslinking agent, a heat stabilizer, an oxidation stabilizer, an ultraviolet absorber, Or a mixture thereof.

A backlight unit according to the present invention for solving the above problems includes a cover bottom including a plurality of reflection patterns formed on a bottom surface and side walls protruding from corners of the bottom surface; A light source unit disposed inside the side wall; Wherein the cover bottom may include a base resin and beads mixed in the base resin and having a hollow therein.

In the backlight unit of the present invention, the beads may be at least one of glass beads, acrylic beads, and amide beads.

In the backlight unit of the present invention, the content of the beads in the resin composition may be 10% by weight to 30% by weight.

In the backlight unit of the present invention, the diameter of the beads may be in the range of 0.55 to 135 mu m.

In the backlight unit of the present invention, the resin composition may further include an inorganic material mixed and formed in the base resin.

In the backlight unit of the present invention, the inorganic material may include at least one of BaSO4, TiO2, and CaCO3, and the shape thereof may be spherical. The diameter of the inorganic material may be in the range of 0.11 to 2 mu m.

In the backlight unit of the present invention, the base resin may be made of a thermoplastic resin, and may be at least one of a polycarbonate resin, a polymethylmethacrylate resin, a polypropylene resin, and a polyethylene resin And may include any one of them.

In the backlight unit of the present invention, the resin composition may further comprise an additive mixedly formed in the base resin, wherein the additive is selected from the group consisting of a fluorescent brightener, a crosslinking agent, a heat stabilizer, an oxidation stabilizer, an ultraviolet absorber, Or a mixture thereof.

In the backlight unit of the present invention, the shape of the reflection pattern may be any one of a prism shape, a lenticular shape, a concave lens shape, a convex lens shape, and a combination shape thereof.

In the backlight unit of the present invention, the sectional shape of the reflection pattern may be any one of a triangle, a quadrangle, a semi-circle, and a combination thereof.

In the backlight unit of the present invention, the reflection pattern may be formed integrally with the cover bottom.

In the backlight unit of the present invention, the cover bottom may be formed by injection molding the resin composition.

According to the present invention, the function of the white reflective sheet is integrated with the cover bottom, thereby simplifying the manufacturing process of the backlight unit and reducing the thickness of the product.

Further, according to the present invention, there is no need to use a conventional light guide plate, the manufacturing cost of the backlight unit can be reduced, and the process efficiency can be improved by omitting the light guide plate processing step.

In addition, according to the present invention, the light reflectance and the uniformity of light supplied to the liquid crystal display panel can be improved even though the light guide plate and the white light reflection sheet are omitted.

In addition, according to the present invention, it is possible to provide a backlight unit capable of improving the brightness of a liquid crystal display device despite the reduction in manufacturing cost, a weight saving effect of the backlight unit due to no use of the conventional light guide plate, It is possible to reduce the weight of the additional backlight unit by forming the cover bottom with the resin composition without using the chassis.

1 schematically shows a conventional edge type backlight unit structure.
Fig. 2 is a schematic view showing the constitution of a resin composition according to an embodiment of the present invention. Fig.
3 illustrates a structure of a backlight unit according to an embodiment of the present invention.
4 is a graph showing the reflectance of the reflective sheet and the high reflection injection specimen according to the prior art.
5 is a graph showing the reflectance of a cover bottom manufactured using the resin composition according to the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. It should be understood, however, that the embodiments described herein and the configurations shown in the drawings are only a preferred embodiment of the present invention, and that various equivalents and modifications may be made thereto at the time of the present application. DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following description, well-known functions or constructions are not described in detail to avoid obscuring the subject matter of the present invention. The following terms are defined in consideration of the functions of the present invention, and the meaning of each term should be interpreted based on the contents throughout this specification. The same reference numerals are used for portions having similar functions and functions throughout the drawings.

The present invention relates to a resin composition for a backlight unit cover bottom (hereinafter, referred to as a 'resin composition') which enables the cover bottom itself to function as a white reflective sheet, which is conventionally used, by manufacturing a cover bottom of the backlight unit with a resin composition containing beads. And a backlight unit manufactured using the same.

2 schematically shows the structure of a resin composition according to an embodiment of the present invention.

2, the resin composition 100 according to the present invention includes a base resin 110, a bead 130 mixedly formed in the base resin 110, and further includes a bead 130 as a pigment. The inorganic material 150 and the additive may be further included.

The base resin 110 is a part constituting the basic constitution of the resin composition 100. As the base resin 110, a thermoplastic resin may be used, and more specifically, a resin such as polycarbonate, polymethylmethacrylate, polypropylene, polyethylene, polyimide, , Polyurethane (Plyyurethane) may be used, but the present invention is not limited thereto.

A plurality of beads 130 having a structure in which a hollow 133 is formed inside and a bead layer 131 is formed on the outer periphery is formed in the base resin 110 as shown in FIGS. 2 (a) and 2 (b) And the beads 130 serve to improve the reflection and diffusion characteristics of light.

The reflectance of light increases in proportion to the number of voids formed in the resin composition. When a void is formed through the foaming process, there is a problem that it is difficult to realize weakness, heat resistance and flame retardancy which are weak to external impact do. However, in the resin composition 100 according to the present invention, instead of forming voids, the beads 130 having the hollows 133 formed therein are mixed and formed in the base resin 110 to improve the reflection characteristics and diffusion characteristics of light Durability can be improved, and heat resistance and flame retardancy can be easily realized.

For example, when the light emitted from the light source is incident on the bead 130, the light is reflected and transmitted by the hollow 133 of the bead 130, diffused, and later diffused at the surface of the reflection pattern of the backlight unit And is emitted to the liquid crystal display panel. At this time, the reflectance and diffusivity of light are increased by the beads 130, so that the light quantity and the uniformity of the outgoing light supplied to the liquid crystal display panel are improved. As a result, the luminance of the liquid crystal display device can be improved.

The bead 130 of the present invention may be generally formed of glass, or may be formed of a polyester resin, a polyacrylic resin, a polystyrene resin, a polycarbonate resin, a polyamide resin or the like having high transparency. It is not.

Meanwhile, the hollow 133 formed in the bead 130 may be filled with air, or may be in a vacuum state. However, this is merely an example, and it is also possible that appropriate design changes such as the filling of a gas such as an inert gas, if necessary, may be made.

The content of the beads 130 may be appropriately adjusted to obtain a desired light diffusion effect, and more specifically, may be adjusted within a range of 10% by weight to 30% by weight based on the total weight of the resin composition 100, But is not limited thereto.

On the other hand, when the diameter of the bead 130 is increased, the transmittance increases and the reflectance decreases. Considering the diffusion effect of the light, the reflectance and the luminance uniformity, the diameter of the bead 130 is formed in the range of 0.55 to 135 탆 However, the present invention is not limited thereto, and may be appropriately adjusted depending on the light diffusion effect and the degree of reflectance.

In addition to the beads 130 described above, the resin composition 100 of the present invention may further include an inorganic material 150 as a pigment for improving the reflectance. The inorganic material may include at least one of BaSO4, TiO2, and CaCO3, and may have a spherical shape. However, the shape of the inorganic material is not limited to a spherical shape, and may be polygonal, hemispherical, . In addition, the diameter of the inorganic material 150 may be appropriately adjusted in consideration of the light diffusion effect and reflectance similarly to the case of the bead 130, and more specifically, it may be formed in a range of 0.11 to 2 탆, but is not limited thereto .

In addition, additives may further be added to the resin composition (100) of the present invention within a range that does not impair the reflection effect and diffusion effect, and examples of such additives include fluorescent whitening agents, crosslinking agents, heat stabilizers, oxidation stabilizers, A material such as an antistatic agent, or a mixture thereof may be used.

The resin composition 100 of the present invention can be melted in the form of a master batch chip at a high concentration and then injection molded to form a backlight unit cover bottom. The thus produced cover bottom can provide durability, heat resistance and flame retardancy . Further, such a cover bottom has an excellent light reflectance and diffusion effect, so that it is possible to provide a backlight unit capable of efficiently supplying light to a liquid crystal display panel without providing a light guide plate and a white reflection sheet, and capable of supplying uniform light do.

3 illustrates a structure of a backlight unit according to an embodiment of the present invention.

2 and 3, a backlight unit 2 according to an embodiment of the present invention may include a cover bottom 300 and a light source 500, and may further include an optical sheet 700 .

The light source 500 serves to provide light to the liquid crystal display panel and may be disposed inside the side wall 350 of the cover bottom 300. The light source unit 500 of the present invention may include a light source 510 for emitting light and a circuit board 530 on which a light source is mounted.

One or more light emitting diodes (LEDs) that emit light may be used as the light source 510. These light sources 510 may be continuously arranged on the circuit board 510 at regular intervals to form an array But is not limited thereto.

As the light source 510, not only a point light source such as a light emitting diode but also a cold cathode fluorescent lamp (CCFL), a hot cathode fluorescent lamp (HCFL), an external electrode fluorescent lamp (EEFL) Fluorescent Lamp) may also be used.

The cover bottom 300 includes a bottom wall 310 and a side wall 350 formed upwardly from the edge of the bottom wall 310. The side wall 350 is formed at each corner of the bottom surface 310 But the present invention is not limited thereto. The bottom surface 310 may have a structure that surrounds the bottom surface 310, or a bottom surface 310 having four sides formed thereon.

In particular, unlike the conventional backlight unit shown in FIG. 1, the cover bottom 100 of the present invention can be manufactured using the resin composition 100 described in the description of FIG. 2, A molding method can be used. That is, since the cover bottom 100 is formed of the resin composition 100 instead of the metal material, the backlight unit 2 of the present invention can remarkably reduce the weight as compared with the conventional backlight unit,

A support member 370 may be further formed at one end of the side wall 350 except for the other end which abuts the bottom surface 310. The support member 370 preferably has the shape of a protruding structure extending from one end of the side wall 350 to the inside of the cover bottom 300 and is preferably formed integrally with the cover bottom 300, And may be coupled to the side wall 350 by being formed separately from the cover bottom 300. [ The support member 370 of the present invention plays a role of supporting the optical sheet 700 to be described later, and can also provide a space in which a separate reflective member can be additionally provided.

A reflection pattern 330 is formed on the bottom surface 310. The reflection pattern 330 reflects and diffuses the incident light to uniformly transmit light to the liquid crystal display panel. That is, the reflective member 500 and the reflective pattern 510 formed on the surfaces of the first reflective member 500 of the present invention convert the incident light, which is performed by the conventional light guide plate, into a planar light source and supply it to the liquid crystal display panel .

The reflection pattern 330 may have a plurality of patterns, and may be formed in a prism shape, a lenticular shape, a concave lens shape, a convex lens shape, or a combination thereof in order to increase the reflection and diffusion effect of light. But is not limited thereto. In addition, the cross-sectional shape of the reflection pattern 330 may have a variety of shapes such as a triangle, a quadrangle, a semicircle, and a sine wave. And the size or density of each pattern may be changed according to the distance from the light source 300. The reflection pattern 330 of the present invention is integrally formed with the cover bottom 300 and can be formed simultaneously with the bottom surface 310 and the side wall 350 in the injection molding process, will be.

The resin composition 100 constituting the cover bottom 300 may have a structure in which the base resin 110 and the beads 130 having a hollow therein are mixed and the inorganic material 150 and additives are further mixed Thereby improving the durability while improving the reflection and diffusing characteristics of light, and it is advantageous in that heat resistance and flame retardancy can be easily realized. Further, by combining the function of the white reflective sheet with the cover bottom 300, the thickness can be further reduced, and the process efficiency can be improved by omitting the white reflective sheet forming process.

Particularly, in the present invention, since the bead 130 is diffused even in the reflection pattern 330, the light reflectance can be further improved and it becomes easier to realize specific reflection characteristics as needed.

For example, when the light emitted from the light source unit 500 is incident on the reflection pattern 330, the reflection pattern 330 reflects the incident light in a Lambertian or Gaussian manner. More specifically, the reflection pattern 330 allows light to be uniformly distributed and emitted by the Lambertian reflection (total reflection) and the Gaussian reflection (diffuse reflection). That is, the light incident on the reflection pattern 330 is subjected to the Lambertian reflection at the surface of the reflection pattern 330 of the cover bottom 300, and at the same time, the light is uniformly spread to the surroundings by the Gaussian reflection. Accordingly, the light incident from the light source can be uniformly emitted without a separate light guide plate. On the other hand, when the light is incident on the bead (130 in FIG. 2) formed inside the reflection pattern 330, the light is reflected and transmitted by the hollow (133 in FIG. 2) of the bead , Is diffused secondarily on the surface of the reflection pattern 330, and is emitted to the liquid crystal display panel. At this time, the reflectance and diffusivity of light are increased by the beads 130, so that the light quantity and uniformity of the outgoing light supplied to the liquid crystal display panel are improved in the future, and as a result, the brightness of the liquid crystal display device is improved without using the light guide plate and the white reflective sheet It is possible to achieve the effect of

The detailed description of the base resin 110, the beads 130, the inorganic material 150, and the additive constituting the resin composition 100 are the same as those described in the description of FIG. 2, and are omitted.

The optical sheet 700 may be disposed on the upper side of the reflection pattern 330 to diffuse and condense the light emitted from the reflection pattern 330. The optical sheet 700 may include at least one of a diffusion sheet, a prism sheet, and a protective sheet, and may be a sheet having a complex function capable of performing all functions of a diffusion sheet, a prism sheet, . For example, the optical sheet 700 of the present invention may be formed by forming a diffusion function in the lower portion of the sheet, forming a prism pattern on the upper portion, and forming a protective layer on the prism pattern.

In the meantime, since the backlight unit 2 of the present invention does not have a light guide plate, the support member 370 may be further formed on the cover bottom 300 to support the optical sheet 700, 700 may be disposed on the upper portion of the support member 370.

Although not shown in the drawings, the backlight unit 2 of the present invention may further include a reflection member at a lower portion of the support member 370 in order to increase the reflectivity of light, May be formed containing an excellent Ag or Ag alloy.

Although not shown in the drawings, according to the present invention, a liquid crystal display device including the above-described backlight unit can be provided.

The liquid crystal display device of the present invention may include a liquid crystal display panel and a backlight unit for supplying light to the liquid crystal display panel.

The liquid crystal display panel includes a color filter substrate and a thin film transistor substrate bonded to the color filter substrate with the liquid crystal layer sandwiched therebetween.

A color filter array includes a black matrix for preventing light leakage, a color filter for color implementation, a common electrode forming a vertical electric field with the pixel electrode, and a color filter array including an upper alignment layer applied thereon for liquid crystal alignment, As shown in FIG. A thin film transistor array including gate lines and data lines formed to cross each other, thin film transistors formed at intersections thereof, pixel electrodes connected to thin film transistors, and a lower alignment film coated thereon for liquid crystal alignment are formed on the thin film transistor substrate May be formed on the lower substrate.

The backlight unit includes a cover bottom including a bottom surface and a side wall protruding from an edge of the bottom surface, a light source disposed inside the side wall, and a reflection pattern formed on the bottom surface, as described in the description of FIG. The cover bottom is made of a resin composition in which beads are mixed with a base resin. Other descriptions are the same as those described in the description of Figs. 2 and 3, and are omitted.

The liquid crystal display device according to the present invention has a manufacturing cost reduction by omitting the light guide plate and has an effect of improving the manufacturing process efficiency by omitting the light guide plate processing step. Further, the total weight reduction effect owing to the omission of the light guide plate and the additional weight reduction effect due to not forming the cover bottoms with metal are provided. And it also has an effect of providing a stable luminance in spite of not including the light guide plate. Further, by forming the cover bottom with the resin composition as described above, it is possible to improve the light reflectance and the uniformity of the emitted light without providing a separate white reflective sheet, thereby reducing the product thickness and improving the manufacturing process efficiency There is also an additional effect.

4 (a) is a graph showing the intensity of light of a white reflective sheet, and FIG. 4 (b) is a graph showing the intensity of light of a reflective sheet and a high reflection injection specimen according to the related art. More specifically, (B) is a graph showing the intensity of light of the high reflection injection specimen. And FIG. 5 is a graph showing the intensity of light of the cover bottom manufactured using the resin composition according to the present invention.

In both FIGS. 4 and 5, the horizontal axis represents the position (angle) of the photodetector, and the vertical axis represents the intensity of light. In Figs. 4 and 5, the integrated value of each graph represents the reflectance of light.

The total reflectance of the material can be expressed by the sum of the Lambertian reflectance and the Gaussian reflectance. Referring to FIGS. 4 and 5, the resin composition of the present invention has an integrated value It can be visually confirmed that the resin composition of the present invention is significantly superior to the conventional white reflector sheet and the high reflection injection specimen in the total reflectance.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, but, on the contrary, Those skilled in the art will appreciate that many suitable modifications and variations are possible in light of the present invention. Accordingly, all such modifications and variations as fall within the scope of the present invention should be considered.

2: Backlight unit
100: Resin composition
110: base resin
130: Bead
131: Bead layer
133: hollow
150: Minerals
300: Cover bottom
310: bottom surface
330: reflection pattern
350: side wall
370: Support member
500: light source part
510: Light source
530: substrate
700: Optical sheet

Claims (28)

A cover bottom including a bottom surface and side walls connected to the bottom surface;
A light source disposed inside the side wall of the cover bottom; And
And an optical sheet disposed on a bottom surface of the cover bottom,
And a reflection pattern formed integrally with a bottom surface of the cover bottom on a bottom surface of the cover bottom,
Wherein the cover bottom comprises a base resin and a resin composition disposed in the base resin, the resin composition including a bead in which a hollow is formed,
And the beads are disposed inside the reflection pattern. The method according to claim 1,
Wherein the bead comprises at least one bead of glass beads, acrylic beads and amide beads. The method according to claim 1,
The base resin may be a backlight including at least one resin selected from the group consisting of polycarbonate, polymethylmethacrylate, polypropylene, polyethylene, polyimide, and polyurethane, unit. The method according to claim 1,
Wherein the beads are contained in an amount of 10% by weight to 30% by weight based on the total weight of the resin composition. The method according to claim 1,
Wherein the diameter of the beads is 0.55 mu m to 135 mu m. The method according to claim 1,
Wherein the resin composition further comprises an inorganic material. The method according to claim 6,
And the diameter of the inorganic material is 0.11 탆 to 2 탆. The method according to claim 6,
Wherein the inorganic material comprises at least one of BaSO4, TiO2 and CaCO3. The method according to claim 1,
The cover bottom further comprises a support member formed to extend from one end of the side wall to the inside of the cover bottom,
And the optical sheet is disposed on the support member. 10. The method of claim 9,
And a reflective member disposed at a lower portion of the support member. The method according to claim 1,
Wherein the reflection pattern is formed protruding from the bottom surface. The method according to claim 1,
Wherein the size and density of the reflection pattern vary with distance from the light source unit. The method according to claim 1,
Wherein the optical sheet includes at least one of a diffusion sheet, a prism sheet, and a protective sheet. The method according to claim 1,
Wherein the hollow is filled with air or an inert gas. 10. The method of claim 9,
Wherein the bottom surface, the side wall, the reflection pattern, and the support member are integrally formed. The method of claim 1, wherein
Wherein the resin composition further comprises an additive mixedly formed in the base resin. 17. The method of claim 16,
Wherein the additive comprises at least one of a fluorescent whitening agent, a crosslinking agent, a heat stabilizer, an oxidation stabilizer, an ultraviolet absorber and an antistatic agent. The method according to claim 1,
Wherein the reflection pattern is formed in at least one of a prism shape, a lenticular shape, a concave lens shape, a convex lens shape, or a combination thereof. The method of claim 1, wherein
Wherein the cross-sectional shape of the reflection pattern is formed in at least one shape of a triangle, a quadrangle, a semicircle, or a combination thereof. The method according to claim 1,
And the light emitted from the light source unit is reflected by the reflection pattern and is directly incident on the optical sheet. The method according to claim 1,
And a lower surface of the optical sheet is disposed in direct contact with the cover bottom. 10. The method of claim 9,
And the lower surface of the optical sheet is disposed in direct contact with the support member of the cover bottom. delete delete delete delete delete delete

Images