WO2005038342A1

WO2005038342A1 - Backlight device

Info

Publication number: WO2005038342A1
Application number: PCT/JP2004/015139
Authority: WO
Inventors: Takayuki Kato; Kazutaka Takasai; Masahiro Machida; Yuuichi Deushi; Koichiro Shimizu; Toshihiro Suzuki; Tetsuya Hamada; Mari Hodate
Original assignee: Oki Electric Industry Co., Ltd.
Priority date: 2003-10-17
Filing date: 2004-10-14
Publication date: 2005-04-28
Also published as: JP4165704B2; JP2005123087A; TW200532327A

Abstract

In a side light-type backlight device where a light source section is provided at a side end face of a light guide plate, an optical reflection coating film having light resistance and heat radiation ability is provided on the inner surface of the reflector. In a directly under-type backlight device that has a lamp house and light emission sources arranged inside the lamp house, the optical reflection coating film is provided on the inner surface of the lamp house. The structures above provide backlight devices and liquid crystal display devices capable of maintaining display quality over a long period.

Description

Specification

Knock light device

Technical field

The present invention relates to a backlight device used for an optical device such as an optical component or an optical device, and a liquid crystal display device having the same.

Background art

[0002] In a conventional sidelight type backlight device, a reflector in which a light emitting source is installed is provided on a side end surface of a light guide plate, and a light incident end face force of the light is applied to the back surface of the light guide plate. The light is scattered and reflected by the reflection sheet provided on the light emitting surface and is emitted from the light exit surface on the opposite side of the reflection sheet, and is used as a backlight of an optical display device such as a liquid crystal panel.

[0003] In this case, the reflective sheet is formed by applying a binder resin containing fine particles to a polymer film made of an organic material such as polyethylene terephthalate and dispersing the fine particles on one surface of the polymer film. It is formed by covering a metal such as silver with a metal thin film layer vacuum-deposited. Alternatively, for example, as described in JP-A-2003-279714, mainly as shown in the right column of page 4 to page 6 and in FIG. 2, the inside of the above-mentioned polymer film or sheet contains acrylic resin or the like. A reflection sheet having scattering reflection characteristics is formed by dispersing a fine filler made of an organic material.

[0004] However, in the above-described conventional technology, a reflection sheet in which a fine filler is dispersed inside a polymer material film which also has an organic material such as polyethylene terephthalate is formed on the inner surface of a reflector such as aluminum. When the inner surface of the reflector is used for reflection of light that emits light, the polymer film of the organic material turns yellow due to the ultraviolet rays of the light from the light source, causing so-called yellowing. As a result, the reflectance may decrease. As a result, display quality such as luminance, contrast, and color unevenness is deteriorated, and it is difficult to maintain the display quality for a long period of time. As a result, the reliability of the backlight device is reduced. .

Summary of the Invention An object of the present invention is to provide a knock light device and a liquid crystal display device that can maintain display quality for a long period of time.

According to the present invention, in a sidelight type backlight in which a light source unit is disposed on a side end surface of a light guide plate, the light source unit includes a light emitting source and a reflector, and the inner surface of the reflector has light resistance and An optical reflection coating having heat radiation is formed!

[0007] In a direct-type backlight including a lamp house and a plurality of light-emitting sources installed inside the lamp house, an inner surface of the lamp house is coated with an optical reflection coating having light resistance and heat radiation. A film is formed.

[0008] Further, a liquid crystal display device including such a backlight is provided.

[0009] Thus, the present invention semi-permanently maintains display quality by preventing yellowing or the like with an optically reflective coating made of an inorganic material against ultraviolet rays irradiated from a light source. The reliability of the backlight is improved.

[0010] Further, since the optical reflection coating film is also excellent in heat radiation, it is possible to suppress a decrease in the luminous efficiency of the luminous source, which has a high cooling effect. Therefore, the current supplied to the light emitting source can be increased, and high luminance can be achieved. Heat leakage to the liquid crystal panel is also suppressed, which improves the display quality of the liquid crystal panel.

Brief Description of Drawings

FIG. 1 is a schematic cross-sectional side view showing a cross section of an embodiment of a liquid crystal display device according to the present invention;

FIG. 2 is a schematic cross-sectional side view similar to FIG. 1, showing a cross section of a liquid crystal display device according to another embodiment of the present invention;

[Figure 3] and

FIG. 4 is a schematic cross-sectional side view showing a cross section of a light source section according to still another embodiment of the present invention. FIG. 5 is a cross-sectional view of a liquid crystal display device according to still another embodiment of the present invention, similar to FIG. Schematic cross-sectional side view of

[Figure 6] and

FIG. 7 is a view for explaining a state of formation of a light absorbing coating film in the example shown in FIG. 5, [FIG. 8] and

FIG. 9 is an exploded view showing a light source unit and a light guide plate according to still another embodiment of the present invention. Perspective view,

[Figure 10] and

[11] A diagram for explaining an embodiment of a backlight device according to the present invention,

[Figure 12] and

圆 13] A schematic cross-sectional side view showing another embodiment of the backlight device according to the present invention,

[Figure 14] and

圆 15] A schematic cross-sectional side view showing still another embodiment of the backlight device according to the present invention. 圆 16] A state of forming a light absorbing coating film on the optical reflection coating film in the embodiment shown in FIG. Figure for the

[17] A schematic view showing still another embodiment of the backlight device according to the present invention.

FIG. 18 is a sectional view taken along line XVIII-XVIII in FIG. 17;

[19] Schematic diagram showing still another embodiment of the backlight device according to the present invention,

圆 20] is a schematic view for explaining an example of the formation of the protrusions in the embodiment shown in FIG. 19;

FIG. 21 is a schematic exploded side view showing a cross section of still another embodiment of the liquid crystal display device according to the present invention;

FIG. 22 is a top view showing the top surface of the embodiment shown in FIG. 21;

[23] A schematic side view showing still another embodiment of the backlight device according to the present invention. [FIG. 24] A schematic side view similar to FIG. 17 showing still another embodiment of the knock light device according to the present invention. ,

FIG. 25 is a top view showing the top surface of the embodiment shown in FIG. 24;

圆 26] Exploded perspective view showing a light source unit in still another embodiment of the present invention. 圆 27] Schematic diagram for explaining a light source unit in still another embodiment of the present invention.

FIG. 28 is a top view showing the top surface of the embodiment shown in FIG. 27;

[Fig.29] and

[30] A schematic diagram for explaining a light source unit in still another embodiment of the present invention,

FIG. 31 is a top view showing a light source unit according to still another embodiment of the present invention.

BEST MODE FOR CARRYING OUT THE INVENTION

Next, an embodiment of a backlight device according to the present invention will be described in detail with reference to the accompanying drawings. . Referring to FIG. 1, Embodiment 1 of the liquid crystal display device according to the present invention is a liquid crystal display device using a sidelight type backlight device. The liquid crystal display device 1 has a liquid crystal panel 2, and a polarizing plate 3 is disposed on the front and back surfaces.

[0013] The liquid crystal display device 1 further includes a reflector 4, which is formed in a box shape with one surface opened by a metal plate such as aluminum. A cold cathode tube 5 as a light emitting source is disposed inside the box as shown in the figure. This is a tubular cold-cathode fluorescent lamp, one or more of which are installed inside the reflector 4, and emits visible light, ultraviolet light, and infrared light when energized. In this embodiment, one cold cathode tube is provided. The light emitting source 5 is not limited to the one described above, and may be, for example, a hot cathode fluorescent lamp.

[0014] The liquid crystal display device 1 also has a light guide plate 6, which is made of a transparent material having a low light absorption and is formed in a substantially rectangular parallelepiped, and has one side end provided with an internal portion as described above. The reflector 4 in which the light emitting source 5 is installed is joined and attached by fitting or butting. The side end surface functions as a light incident end surface 6a where light from the light emitting source 5 enters the light source 4 directly. In the present embodiment, the reflector 4 and the light source having the same strength as the cold-cathode tube 5 as the light-emitting source are joined and attached to the light guide plate 6 by fitting.

The light that has entered the light guide plate 6 from the light incident end surface 6a is reflected by the reflection sheet 7 provided on the back surface 6b of the light guide plate 6, and the surface on the opposite side, that is, the light exit surface 6c also has a force. Inject. This light is applied to the liquid crystal panel 2 via the lens sheet 8, the diffusion sheet 9 as a light diffusion member, and the polarizing plate 3. The reflection sheet 7 of the present embodiment is a light-reflective sheet member having a scattered reflection characteristic by dispersing a fine filler in the sheet.

An optical reflection coating 10 is provided on the inner surface of the reflector 4. This is because after applying a paint containing a liquid binder containing an inorganic filler formed as fine particles of white metal oxide, white metal nitride, white metal carbide or white metal sulfide, This is a white coating film formed by drying this.

As described above, the reflector 4, the light source unit having the same power as the light emitting source 5, the light guide plate 6, the reflection sheet 7, the lens sheet 8, and the diffusion sheet 9 constitute a sidelight type backlight device. .

[0018] The white metal oxide used as the inorganic filler of the optical reflection coating 10 is magnesium oxide, alumina, silicon oxide, calcium oxide, titanium oxide, yttrium oxide, zinc oxide, or the like. Use at least one of these materials, such as zirconium oxide.

The white metal nitride 2b may be silicon nitride, niobium nitride, molybdenum nitride, or the like, and at least one of them is used. As the white metal carbide 2c, use at least one of silicon carbide and titanium carbide. The white metal sulfide 2d is a sulfuric acid barrier or the like.

[0020] As the binder described above, at least one of these used in silicone emulsion, silicone resin or the like is used. In the case of paint, at least one of them is used as a liquid.

[0021] In the case of Noinder, a transparent coating film formed of inorganic material formed when the solvent contained in the binder is evaporated by drying after application has a bonding function, and the bonding between inorganic fillers is shown in FIG. It exerts a function such as adhesion to an object such as the inner surface of the reflector 4.

[0022] The paint for forming the optical reflection coating film 10 is basically composed of an inorganic filler and a liquid binder. The inorganic filler is a white metal oxide, metal nitride, metal carbide, or the like. It is sufficient for the metal sultanate to contain at least one of them. It is desirable that the ratio of the inorganic filler to the paint is 5% by weight or more and 85% by weight or less.

[0023] The binder having such a configuration, when applied alone and dried, forms a transparent coating film made of an inorganic material, and has a heat-radiating transparent property of radiating absorbed heat to the outside by heat radiation. It can be used as a coating film. Such a coating film will be described later as a heat-radiating transparent coating film 11. Since the binder is made of the above-mentioned inorganic material, it can maintain its transparency semipermanently without yellowing even with ultraviolet rays or the like.

[0024] The optical reflection coating film 10 has excellent scattering reflection characteristics due to unevenness of the surface of the coating film and a white inorganic filler. The optical reflection coating 10 is also an inorganic material in which an inorganic filler is bonded by a transparent coating made of an inorganic material, and thus has excellent light resistance. In particular, it has extremely excellent light resistance to ultraviolet light as compared to organic materials, and can maintain its reflection characteristics semipermanently without yellowing even when irradiated with ultraviolet light for a long time.

[0025] In addition, an inorganic filler such as a metal oxide included as a constituent material of the optical reflection coating film 10 as a white coating film has a function of converting infrared light or far infrared light into heat, and a function of converting heat from infrared light or infrared light. It has the function of converting into far-infrared rays and radiating it. Therefore, it has superior heat radiation properties as compared with a normal white coating film or a heat-radiating transparent coating film 11, and has a function of releasing absorbed heat to the outside by heat radiation.

[0026] The inner surface of the reflector 4 on which the optical reflective coating film 11 is formed may be a reflective surface such as a metal mirror surface or a non-reflective surface. In short, if the optical reflection coating 11 is formed on the inner surface of the reflector 4, the above-mentioned function can be exhibited.

[0027] The operation of the liquid crystal display device having such a configuration will be described. Light emitted from the cold cathode tube 5 is scattered by light entering the light guide plate 6 directly into the light guide plate 6 and by the white optical reflection coating 10 formed on the inner surface of the reflector 4. There is light that enters the light guide plate 6 while being reflected. Ultraviolet rays are also emitted from the cold cathode tube 5, but the optical reflection coating 10 is an inorganic material as described above, so that display quality can be maintained semi-permanently without yellowing or the like. Therefore, the reliability of the knock light device can be improved.

By the way, a metallic reflector provided with a reflection-enhancing film or the like is excellent in heat conduction but inferior in heat radiation. For this reason, if such a metal rearrangement area is provided, the temperature of the light source section is high, which exceeds the optimal temperature of the cold cathode fluorescent lamp 5, and the luminous efficiency of the cold cathode fluorescent lamp 5 is reduced, resulting in low brightness. In other words, heat near the light source would be transmitted to the liquid crystal panel 2, and the contrast and transmittance of the liquid crystal panel 2 would be reduced, which would have caused the display quality to be lowered. However, since the optical reflective coating film 10 of the present embodiment also has excellent heat radiation as described above, the cooling effect due to heat radiation is added to the cooling effect due to the high thermal conductivity of the reflector 4, and the cooling effect is increased. A decrease in the luminous efficiency of the cold cathode tube 5 can be suppressed. Therefore, it is also possible to increase the current supplied to the cold cathode tube 5 to increase the luminance. Further, heat outflow to the liquid crystal panel 2 can be suppressed, and display quality can be improved.

Referring to FIG. 2, a liquid crystal display device 2 according to another embodiment of the present invention has an optical reflection coating 10 formed on the outer surface of a reflector 4. In this specification, the same elements are denoted by the same reference numerals, and redundant description will be omitted.

In the present embodiment, the following effects are further obtained by forming such an optical reflection coating film 10. That is, due to the action of converting the heat of the optical reflection coating film 10 into infrared rays, the heat radiation on the outer surface of the reflector 4 is improved, and the cooling effect of the light source unit is further enhanced. Ma In addition, it is possible to further suppress the performance deterioration of the cold-cathode tube 5 and increase the brightness, and further improve the display quality of the liquid crystal panel 2.

[0031] Even if the heat-radiating transparent coating film 11 is formed on the outer surface of the reflector 4, the cooling effect by the heat radiation can be obtained. In this case, the coating film formed on the outer surface of the reflector 4 is not limited to the heat-radiating transparent coating film 11 described above, but may be any heat-radiating coating film. A cooling effect according to the degree is obtained. Such a heat-radiating coating may be an optically opaque coating.

Referring to FIG. 3, the embodiment of the light source section has a reflection-enhancing film 20, which is formed by depositing a metal such as silver on the inner surface of the reflector 4 by vapor deposition or the like. It reflects light from the sky. In this embodiment, a heat-radiating transparent coating film 11 is formed on the inner surface of the reflection-enhancing film 20, as shown in FIG.

[0033] In such a configuration, the heat radiation property of the reflector 4 is improved by the heat radiation transparent coating film 11, which can maintain transparency semipermanently, without hindering the reflection characteristics of the enhanced reflection film 20. As a result, it is possible to suppress a decrease in the luminous efficiency of the cold-cathode tube 5 and to increase the brightness, and also to suppress a heat outflow to the liquid crystal panel 2, thereby improving the display quality. In addition, as shown in FIG. 4, if the heat-radiating transparent coating film 11 is also formed on the outer surface of the reflector 4, the above-mentioned effect can be further enhanced.

Referring to FIG. 5, the liquid crystal display device 1 of this embodiment has a light absorbing coating film 2 which is a coating film of a paint having a predetermined light absorption. The light-absorbing film 2 is formed by fitting the reflector 4 and the light guide plate 6 by fitting, and provided at or near the fitting portion and Z. The predetermined light absorption may be, for example, about 5 to 20% in terms of light absorption.

With reference to FIGS. 6 and 7, the state of formation of the light absorbing coating film in this example will be described. As shown in FIG. 6, the light absorbing coating film 21 may be formed on the fitting portion of the inner surface of the optical reflection coating film 10 formed on the inner surface of the reflector 4 and at or near Z. Also, as shown in FIG. 7, the light guide plate 6 is formed at the fitting portion of the light guide plate 6 with the reflector 4 and at or near Z.

In general, the light immediately after entering the light guide plate does not have uniform light intensity depending on the location. In addition, the shape of the edge portion of the light guide plate near the edge of the light incident end surface may be indeterminate. In such a case, there is light that also emits the light exit surface force of the light guide plate due to the edge portion. As a result, conventionally, a region having a high luminance is generated near the light source portion of the liquid crystal panel, and the display quality is deteriorated.

However, in this embodiment, since the light absorbing coating film 21 is formed at the fitting portion of the reflector 4 and at or near Z, the brightness of the backlight near the light source portion is reduced by a predetermined amount, and the display quality is reduced. Further improve.

In the embodiment shown in FIGS. 6 and 7, the light absorbing coating film 21 is formed on the fitting portion of the light guide plate 6 and on the light exit surface 6c and the back surface 6b at or near Z. . However, instead of this, it may be formed over the entire circumference of the fitting portion, or may be formed only on a part of the fitting portion, for example, only a portion where the luminance needs to be improved.

The light-absorbing coating film 21 on the inner surface of the reflector 4 may be formed by coating the optical reflection coating film 10 formed on the inner surface of the reflector 4 as described above, The portions where the coating film 10 and the light absorbing coating film 21 are formed may be adjacent to each other and formed separately.

When the reflector 4 is joined and assembled by abutting, the light absorbing coating film 21 is formed in the vicinity of the abutting portion and the abutting portion of the reflectors 4 and Z or the light guide plate 6 in the same manner as described above. Yeah. Thereby, a similar effect can be obtained.

Referring to FIG. 8, in this embodiment, the light guide plate 6 has both light guide plate side end surfaces 6d adjacent to the light incident end surface 6a and the opposite side end surface 6e of the light guide plate 6 facing the light incident end surface 6a. An optical reflection coating 10 is formed on the substrate.

With this configuration, even if the light incident on the light guide plate 6 hits the opposing end surface 6e or both the light guide plate end surfaces 6d, the light is effectively reflected, and the light guide plate 6 Go inside. Therefore, the reflected light is effectively used, and the optical reflection coating film 10 is not yellowed, so that the knock light can be semi-permanently increased in brightness. In addition, the cooling effect of the light guide plate 6 is enhanced by the heat radiation property of the optical reflection coating film 10, so that heat leakage to the liquid crystal panel 2 can be suppressed, and the display quality can be improved.

[0043] The same effect can be obtained by forming such an optical reflection coating film 10 on any of the three side end surfaces described above. In addition, a heat radiation transparent coating film 11 may be formed instead of the optical reflection coating film 10, and the heat radiation property of the heat radiation transparent coating film 11 can enhance the cooling effect of the light guide plate 6. As shown in FIG. 9, in the example in which the light source 5 is also provided on the opposite end surface 6e, similarly to the above-described example, one or both of the light guide plate end surfaces 6d have the optical reflection coating 10 or the heat-radiating transparent film. When the coating film 11 is formed, the same effect as in the above-described example can be obtained. When a light source is provided on the opposing end face 6e, the opposing end face 6e of the light guide plate 6 may be slightly extended in order to obtain a fitting portion or abutting portion for joining.

Referring to FIG. 10, the backlight device of this embodiment has a fine pattern 22. This is a dot-like pattern formed by the optical reflection coating 10 and is printed in a dot shape on the surface opposite to the light exit surface 6c of the light guide plate 6, that is, on the back surface 6b using the optical reflection coating 10. Have been. As shown by an arrow A in FIG. 11, the fine pattern 22 is formed so that the density of dots is low in the vicinity A1 of the light source portion and the density increases as the power of the light source portion increases (A2). In this way, the degree of density is set so that the luminance distribution on the light exit surface 6c becomes uniform as a whole.

With this configuration, good backlight efficiency is maintained semipermanently due to the scattering and reflection characteristics of the optical reflection coating film 10 that does not cause yellowing. At the same time, the cooling effect of the light guide plate 6 is enhanced due to the heat radiation, and the heat leakage to the liquid crystal panel 2 is suppressed, and the display quality is improved.

The fine pattern 22 is not limited to the dot shape as described above, and may be a line shape in the longitudinal direction of the cold cathode tube 5. Further, in the example in which the light source units are arranged on both sides, the fine pattern may be formed such that the fine pattern substantially at the center is dense and becomes sparser toward the light source unit side.

Further, if the heat-radiating transparent coating film 11 is formed on the back surface 6b of the light guide plate 6 so as to cover the fine pattern 22, in addition to the heat radiation effect, the fine pattern 22 is peeled off by mechanical rubbing. Can be prevented.

Referring to FIG. 12, the backlight device of this embodiment has a base sheet 23, which is a film of a resin material or a metal material that can withstand the drying temperature when forming the optical reflection coating film 10.部材 Sheets and plates. As shown in the figure, the base sheet 23 is formed on the entire surface of one surface of the optical reflection coating 10, and the optical reflection coating 10 is opposed to the surface on the opposite side of the light exit surface 6c of the light guide plate 6, that is, the back surface 6b. And is arranged instead of the reflection sheet 7. Of this embodiment The base sheet 23 is a metal plate such as aluminum.

[0050] With this configuration, the base of the metal plate can be pressed by force if semi-permanently good backlight efficiency can be maintained by the scattering reflection characteristics of the optical reflection coating film 10 that does not cause yellowing. Due to the heat conductivity of the sheet 23 and the heat radiation property of the optical reflection coating 10, the heat of the light guide plate 6, in particular, the heat of the light source part is efficiently radiated to the rear surface 6 b side of the light guide plate 6, and is transmitted to the liquid crystal panel 2 And the display quality is improved by suppressing the heat leakage.

As shown in FIG. 13, a heat-radiating transparent coating 11 is formed on the back surface 6 b side of the light guide plate 6 of the optical reflection coating 10 formed on the base sheet 23 to protect the optical reflection coating 10. May be. This prevents damage such as peeling of the optical reflection coating 10 and falling off of the inorganic filler due to mechanical influences such as rubbing between the light guide plate 6 and the optical reflection coating 10 without affecting the optical characteristics. can do.

Referring to FIG. 14, in this embodiment, the backlight device shown in FIG. 12 is housed in a housing 24 formed of a metal plate or the like of aluminum or the like. In this case, the optical reflection coating film 10 is formed directly on the back surface 6b side of the light guide plate 6 of the housing 24, and the base sheet 23 shown in FIG. 12 is omitted. FIG. 15 shows an example in which the heat-radiating transparent coating film 11 is formed as in the example shown in FIG.

With this configuration, the same effect as described above is obtained, the base sheet 23 is omitted, and the manufacturing cost of the knock light device is reduced.

In the embodiment shown in FIGS. 12 to 15, an optical reflection coating 10 and a heat-radiating transparent coating 11 may be formed outside the base sheet 23 and the housing 24. By doing so, the cooling effect of the light guide plate 6 can be enhanced from the respective heat radiation properties.

FIG. 16 shows a state in which the light absorbing coating film 21 in the embodiment shown in FIG. 5 is formed on the light source side B of the optical reflection coating film 10. More specifically, the light-absorbing coating 21 is bonded to the base sheet 23 viewed from the back surface 6b side of the light guide plate 6 in FIG. 12 or to the light source portion of the optical reflection coating 10 formed on the housing 24 in FIG. It is formed near the portion. That is, in the case of joining by butting, it is formed at the butting portion and its vicinity, and in the case of joining by fitting, it is formed at or near the fitting portion and Z.

As a result, the difference S in luminance between the vicinity of the light source portion of the light guide plate 6 and the other portions is reduced. The same effect as the embodiment shown in FIG. 5 can be obtained.

When the light source units are arranged on both sides of the light guide plate 6 as shown in FIG. 9, the light absorbing coating 21 may be provided on each light source unit side. The same applies to the case where the light-absorbing coating film 21 is provided on the light guide plate 6 as shown in FIG.

In each of the above-described embodiments, the cold cathode tube 5 is applied as a light source of the sidelight type backlight device of the liquid crystal display device 1. When this cold cathode tube 5 is used, problems such as a reduction in luminous efficiency and life may occur unless the temperature of the cold cathode tube 5 is optimized as described above. That is, the cold-cathode tube 5 has an optimal temperature range in which the luminous efficiency is maximized. This temperature range is generally 70-80 ° C. Either lower or higher will decrease the luminous efficiency. As for the life, when the temperature increases, the electrode deteriorates, and the life is shortened.

In the conventional liquid crystal display device, there is a problem that the cooling of the cold cathode tubes 5 is often insufficient, and the temperature of the cold cathode tubes 5 becomes higher than the optimum range. This problem has been solved in the above embodiments.

When the cold cathode tube 5 is cooled, if the entire cold cathode tube 5 is uniformly cooled, the life can be prolonged. However, if the vicinity of the electrode of the cold-cathode tube 5 is cooled so as to be the coldest due to manufacturing variations, etc., the mercury inside the cold-cathode tube 5 tends to collect near the electrode when the lamp is turned off, and the lamp is turned on again. In some cases, mercury is consumed by electrode sputtering, and the luminous efficiency and life of the cold cathode tube 5 may be reduced. Therefore, it is desirable to locally cool a portion of the cold-cathode tube 5 where the electrode strength is far, and to keep the entire tube at an optimum temperature.

[0061] In other words, the luminous efficiency of the cold cathode tube 5 depends on the mercury vapor pressure of mercury present in the cold cathode tube 5. For this reason, if it is not necessary to cool the entire cold-cathode tube 5, the heat generated due to the light emission of the cold-cathode tube 5 is suppressed by local cooling, and if the temperature is maintained in an optimum temperature range, the above fear is wiped out, and the cooling is performed. The life of the cathode tube 5 can be extended.

Referring to FIG. 17, still another embodiment of the knock light device according to the present invention is shown in a state where the light guide plate 6 is also viewed from the light exit surface 6c side. One-dot chain line in FIG.

A cross section taken along XVII-XVII is shown in FIG.

As can be seen from these figures, the backlight device of the embodiment has a heat radiating section 30. heat The radiating portion 30 is formed by the optical reflection coating film 10, and is a surface of the inner surface of the reflector 4 which faces the light incident end surface 6 a of the light guide plate 6, that is, substantially the middle of the light incident end surface facing surface 31 in the longitudinal direction of the cold cathode tube 5. In the central part, the light incident end face facing surface 31 is provided over substantially the entire length in a direction orthogonal to the longitudinal direction of the cold cathode tubes 5.

[0064] In this example, the length of the heat radiating portion 30 formed by the optical reflection coating film 10 is lmm or more, and preferably about 20mm. Also, a thickness of 10 m or more is sufficient. The end is located at a predetermined distance C from the electrode 5a of the cold-cathode tube 5, preferably at a distance of 20 mm or more. Further, the inner surface of the reflector 4 is a metal mirror surface or the enhanced reflection film 20 up to a range including the light incident end surface facing surface 31.

[0065] With this configuration, even if light hits the heat radiating portion 30 formed by the optical reflection coating 10, the light is scattered and reflected, and light absorption hardly occurs. Therefore, there is no danger of luminance drop. Further, since the heat radiation of the optical reflection coating film 10 is higher than that of the base material of the reflector 4, for example, an aluminum material, the cold cathode tube 5 is in a state of being easily cooled, and local cooling in this portion is realized.

The heat radiating section 30 may be formed of the heat radiating transparent coating film 11. In this case, the same local cooling as described above is realized by the heat radiation.

Referring to FIG. 19, a knock light device according to still another embodiment of the present invention is shown in a state where the force on the light exit surface 6c of the light guide plate 6 is also viewed. In the figure, the knock light device 6 has a projection 32 formed. The convex portion 32 is located at a substantially central portion in the longitudinal direction of the cold cathode tube 5 on the light incident end face opposing surface 31 of the inner surface of the reflector 4 in the longitudinal direction of the cold cathode tube 5, protrudes toward the cold cathode tube 5, and The end facing surface 31 is provided over substantially the entire length in a direction perpendicular to the longitudinal direction of the cold cathode tubes 5.

[0068] In this example, the length of the convex portion 32 is lmm or more, and preferably about 20mm. Its height is not less than 10 / z m and is set so as not to be in contact with the cold cathode tube 5. The end is located at a predetermined distance C from the electrode 5a of the cold-cathode tube 5, preferably at least 20 mm. On the inner surface of the reflector 4 of the present embodiment, an optical reflection coating 10 is formed on the entire surface including the convex portion 32.

[0069] With such a configuration, the distance between the protruding portion 32 and the cold cathode tube 5 is short. The cold-cathode tube 5 tends to cool down in the area, and local cooling is realized while maintaining the optical characteristics due to scattered reflection semipermanently by the optical reflection coating film 10 which does not yellow.

[0070] The projections 32 may be formed by embossing the optical reflection coating film 10 as shown in FIG. By doing so, similarly to the case shown in FIG. 19, the light from the cold cathode tube 5 is scattered and reflected by the optical reflection coating 10, and the reflection characteristics of the convex portions 32 formed by the optical reflection coating 10 are different from those of the other cases. Because the distance between the projection 32 and the cold cathode tube 5 is short, the cold-cathode tube 5 does not cool down and does not immediately turn yellow. Optical characteristics due to scattering reflection are maintained semipermanently, and local cooling is realized.

Note that the optical reflection coating film 10 on the inner surface of the reflector 4 provided with the projection 32 may be omitted, and a metal mirror surface or the enhanced reflection film 20 may be used. In this case, too, local cooling is realized because the distance between the convex portion 32 and the cold cathode tube 5 is short.

The respective embodiments described above may be combined as appropriate, whereby the effects of the respective embodiments are achieved in parallel.

In the above embodiment, the optical reflection coating film 10 and the heat-radiating transparent coating film 11 were applied to the sidelight type knock light device used in the liquid crystal display device 1. By the way, generally, liquid crystal display devices of about 20 inches or more generally have a direct type in which a light source unit is disposed immediately below a liquid crystal panel. Hereinafter, an example in which the optical reflection coating 10 and the heat-radiating transparent coating 11 are applied to a direct-type backlight device will be described.

Referring to FIG. 21, still another embodiment of the present invention is a liquid crystal display device having the direct-type backlight device. The same drawing shows a cross section thereof. This liquid crystal display device has a lamp house 40, on which an optical reflection coating film 10 is formed. A plurality of cold cathode tubes 5 are installed inside the lamp house 40, and light from the cold cathode tubes 5 is scattered and reflected by the optical reflection coating 10 on the inner surface of the lamp house 40. The reflected light is emitted to the liquid crystal panel 2 via a diffusion plate 41 as a light diffusion member and a polarizing plate 3 installed in the opening of the lamp house 40. FIG. 22 shows an upper surface from which the diffusion plate 41, the liquid crystal panel 2, and the polarizing plate 3 have been removed.

The light source section of the direct type apparatus is configured by a lamp house 40, a plurality of cold cathode tubes 5, and the like, and the knock light apparatus is configured by the light source section, a diffusion plate 41, and the like. [0076] By using the optically reflective coating film 10 which also has an inorganic material having a reflective property and which is also an organic material, the reflection sheet which is conventionally disposed on the inner surface of the lamp house 40 and which also has an organic material can be yellowed by ultraviolet rays. As a result, the problem of deterioration in reflection characteristics is solved, and the reflection characteristics without yellowing due to long-term irradiation with ultraviolet rays are maintained semipermanently.

[0077] In addition, since the optical reflection coating film 10 is also excellent in heat radiation, the lamp house 40 is made of aluminum. Conductivity and optics Due to the heat radiation of the reflective coating film 10, it is efficiently released to the outside and has a high cooling effect. In addition, it is possible to suppress a decrease in the luminous efficiency of the cold cathode tube 5, and to increase the current supplied to the cold cathode tube 5, thereby achieving higher luminance. In addition, heat outflow to the liquid crystal panel 2 can be suppressed, and the display quality is improved.

Further, since the distance between the cold cathode tube 5 and the lamp nose 40 is short, the liquid crystal display device 1 having the direct-type backlight device is thinned.

[0079] On the outer surface of the lamp house 40, if the optical reflection coating 10 and the heat-radiating transparent coating 11 are formed in the same manner as in the embodiment described with reference to Fig. 2, A further cooling effect corresponding to each heat radiation property is achieved.

Referring to FIG. 23, in the backlight device of this embodiment, the base sheet 23 is an aluminum plate. In this case, similarly to the embodiment described above with reference to FIG. 12, the optical reflection coating film 10 is formed on one surface thereof, and is disposed on the inner surface of the lamp house 40 by bonding or the like.

With such a configuration, even if a hole is formed in the lamp nose 40, the hole can be closed by the base sheet 23 in addition to the effects of the embodiment shown in FIG. This prevents light from leaking from the outside to the outside and intrusion of dust and the like by external force. Further, a circuit board or the like can be easily attached to the outer surface of the lamp nozzle 40.

Referring to FIG. 24, in the backlight device of this embodiment, a conventional reflection sheet 7 is disposed on the inner surface of a lamp 40 and a mouse 40. An optical reflection coating film 10 is formed in a region of the reflection sheet 7 near each cold cathode tube 5 facing the cold cathode tube 5, that is, in the facing region 43. FIG. 25 shows the upper surface in a state where the diffusion plate 41 is removed.

With this configuration, the optical reflection coating film 10 made of an inorganic material prevents the reflection sheet 7 from yellowing in the facing region 43 where the strongest ultraviolet light is irradiated from the cold cathode tubes 5. In other areas where the irradiation of ultraviolet rays is small, even if the reflection sheet 7 is made of a conventional material, the reflection sheet 7 can sufficiently withstand the irradiation. For this reason, even if a conventional material is applied to the reflection sheet 7 where the optical characteristics such as luminance do not decrease, the life can be extended.

[0084] If a heat-radiating transparent coating film 11 is further formed on the optical reflection coating film 10 in the facing area 43, the optical characteristics can be maintained as it is, and the optical reflection coating film 10 can be further prevented from peeling off. I can do it.

Further, referring to FIG. 26, there is shown an embodiment of the light source unit, which has a lamp holder 44. The lamp holder 44 of the embodiment is made of a resin material, a synthetic rubber, a nonmetal material, or the like, and fixes both sides of the plurality of cold cathode tubes 5. In this embodiment, the lamp holder 44 is made of a resin material.

[0086] An optical reflection coating 10 is formed on the surface of the lamp holder 44 to which the cold cathode tube 5 is fixed. The lamp holder 44 is also fixed inside the lamp house 40 having the optical reflection coating 10 formed on the inner surface.

With this configuration, in addition to the effect of the embodiment shown in FIG. 21, in the lamp holder 44 made of a resin material, yellowing due to ultraviolet rays from the cold cathode tube 5 is also prevented. In addition, a situation in which the screen near the lamp holder 33 of the liquid crystal screen becomes yellowish is prevented, and a long-life backlight device is achieved.

In each of the embodiments described with reference to FIG. 21 and subsequent figures, the cold cathode tube 5 is applied as a light emitting source of the direct type backlight device of the liquid crystal display device 1. Similar to the case where such a cold cathode tube 5 is used as a light source of a side-light type backlight device, even when the cold cathode tube 5 is used as a light source of a direct-type knock light device, a cold cathode tube is also used. If the temperature of the tube 5 is not optimized, there is a possibility that luminous efficiency and life will be reduced, and the same applies to cooling near the electrode. For this reason, even when cooling the cold cathode tube 5 of the direct-type backlight device, a portion far from the electrode power is locally cooled, and the local cooling suppresses the heat generated by the light emission of the cold cathode tube 5. It is important to achieve an optimal temperature range.

Referring to FIG. 27 and FIG. 28 which is a top view thereof, the light source section in still another embodiment of the present invention has a heat radiation area 50, which is formed by the optical reflection coating 10. I have. As can be seen from both figures, the heat radiating area 50 is provided on the inner surface of the lamp house 40 as shown in FIG. The surface facing the diffusion plate 41 as the light diffusion member in the example, that is, the reflection surface 51 is located substantially at the center of the cold cathode tube 5 in the longitudinal direction, and is orthogonal to the reflection surface 51 in the longitudinal direction of the cold cathode tube 5. It is provided over substantially the entire length in the direction.

[0090] In this embodiment, the length of the heat radiation region 50 formed by the optical reflection coating film 10 is 1 mm or more, preferably about 20 mm. A thickness of at least 10 m is sufficient. Further, the end is disposed at a position separated from the electrode 5a of the cold cathode tube 5 by a predetermined distance C, preferably 20 mm or more. The reflection sheet 7 is bonded to the inner surface of the lamp nose 40 including the reflection surface 51.

[0091] With this configuration, even if light hits the heat radiation region 50 formed by the optical reflection coating 10, this light is scattered and reflected, and light absorption hardly occurs. Therefore, there is no danger of luminance drop. In addition, since the heat radiation of the optical reflection coating film 10 is higher than the base material of the reflector 4, for example, an aluminum material, it is possible to realize local cooling when the cold cathode tube 5 cools down or the reflection sheet 7 is used immediately.

[0092] On the inner surface of the lamp house 40, an optical reflection coating film 10 that does not cause yellowing may be formed. In this case, the reflecting surface 51 may be included. By doing so, the reflection characteristics can be maintained semi-permanently, and the heat radiation allows heat to be radiated from the inner surface of the lamp house 40, thereby increasing the cooling effect of the entire backlight device and In addition, local cooling of the cold-cathode tube 5 is also realized by the optical reflection coating 10 in the heat radiation region 50 located near the surface of the cold-cathode tube 5.

[0093] The heat radiation region 50 may be formed of the heat radiation transparent coating film 11. In this case, local cooling can be achieved in the same manner as described above due to its heat radiation.

Referring to FIG. 29, the light source unit in still another embodiment of the present invention has a convex portion 32. The convex portion 32 projects toward the cold cathode tube 5 at a substantially central portion in the longitudinal direction of the cold cathode tube 5 of the reflecting surface 51 on the inner surface of the lamp house 40 in the longitudinal direction of the cold cathode tube 5 so as to face the cold cathode tube 5. The cathode tube 5 is provided over substantially the entire length in a direction orthogonal to the longitudinal direction.

[0095] In this embodiment, the length of the convex portion 32 is lmm or more, and preferably about 20mm. The height is set to a value not less than 10 / zm and not in contact with the cold cathode tube 5. The end is located at a predetermined distance C from the electrode 5a of the cold-cathode tube 5, preferably 20 mm or more. . Further, an optical reflection coating film 10 is formed on the entire inner surface of the lamp house 40 including the projections 32.

[0096] With such a configuration, since the distance between the convex portion 32 and the cold cathode tube 5 is short, the optically reflective coating film 10 in which the cold cathode tube 5 does not cool down or immediately turns yellow in this portion. Local cooling is achieved while the reflective properties are maintained semi-permanently.

[0097] The convex portions 32 may be formed by pressing the optical reflection coating film 10 as shown in Fig. 30 or may be formed by embossing the optical reflection coating film 10 by coating. Good. Also in this case, similarly to the case of FIG. 29, the light from the cold cathode tube 5 is scattered and reflected by the optical reflection coating 10. The reflection characteristics of the projections 32 formed by the optical reflection coating film 10 are the same as those at other places. Further, since the distance between the convex portion 32 and the cold cathode tube 5 is short, the same effects as described above can be obtained.

[0098] The reflection sheet 7 may be provided by omitting the optical reflection coating film 10 on the inner surface of the lamp house 40 provided with the projections 32. Also in this case, since the distance between the convex portion 32 and the cold cathode tube 5 is short, local cooling is achieved.

[0099] Lastly, referring to Fig. 31, the light source unit according to still another embodiment of the present invention has a plurality of heat radiation regions 50a to 50h as can be seen from the top view. These heat radiating regions 50a to 50h are obtained by dividing the heat radiating regions 50 in the embodiment described with reference to FIG. 28 and displacing the positions thereof corresponding to the plurality of cold cathode tubes 5, respectively. It corresponds to the state. The ends of the heat radiation regions 50a to 50h are arranged at the above-mentioned predetermined distance C from the electrode 5a of each cold cathode tube 5, that is, at a position separated by 20 mm or more.

With such a configuration, a local cooling effect similar to that of the embodiment shown in FIG. 28 can be obtained. Since the heat radiation areas 50a to 50h on which the optical reflection coating 10 is formed are dispersedly arranged, the reflection sheet 7 is provided on the inner surface of the lamp nose 40, and between the reflection sheet 7 and the optical reflection coating 10. However, even when the reflection characteristics are different, the occurrence of luminance unevenness and color unevenness of the backlight is reduced, and the display quality can be maintained.

Note that the same local cooling effect as in the embodiment of FIG. 29 can be obtained even if the protrusions 32 in the embodiment shown in FIG. 29 are divided and arranged in the same manner.

[0102] The embodiments shown in Fig. 21 and thereafter may be combined as appropriate, whereby the effects of the respective embodiments are obtained in a superimposed manner. [0103] In these examples, the optical reflection coating film and the heat-radiating transparent coating film were formed by directly applying to the reflector 4 and the lamp house 40. However, the formation of the optical reflection coating or the heat-radiating transparent coating on the reflector 4 or the lamp nose 40 is not limited to this. For example, an optical reflection coating or a heat-radiating transparent coating may be applied to a base sheet or the like in the examples shown in FIGS. May be formed and bonded together. In that case, the base sheet is preferably transparent when it is a heat-radiating transparent coating film.

[0104] All disclosures including Japanese patent application, Japanese Patent Application No. 2003-358318, filed on October 17, 2003, including the specification, claims, accompanying drawings, and abstract, are incorporated herein by reference. All of that is included and referenced.

[0105] Although the present invention has been described with reference to specific examples, the present invention is not limited to these examples. It should be recognized that those skilled in the art can change or modify these embodiments without departing from the scope and concept of the invention.

Claims

The scope of the claims

[1] In a sidelight type backlight device in which a light source unit is arranged on a side end surface of a light guide plate, the light source unit includes a light emitting source and a reflector, and the inner surface of the reflector has light resistance and heat radiation. Backlight device having an optical reflection coating film having the same

[2] The apparatus according to claim 1, wherein the optical reflection coating is formed on an outer surface of the reflector! A backlight device characterized in that the backlight device is provided.

3. The backlight device according to claim 1, wherein a transparent coating film having a heat radiation property is formed on an outer surface of the reflector.

[4] The knock light device according to claim 1, wherein a coating film having a predetermined light absorption is formed on a portion of the inner surface of the reflector that abuts with the light guide plate and in the vicinity thereof. .

[5] The device according to claim 1, wherein a coating film having a predetermined light absorption is formed in the outer surface of the light guide plate near the fitting portion with the reflector and the Z or the fitting portion. A backlight device, which is provided.

[6] In a backlight device of a sidelight type in which a light source unit is disposed on a side end surface of a light guide plate, the light source unit includes a light emitting source and a reflector, and an inner surface of the reflector has a heat-radiating transparent surface. A backlight device characterized in that a light-resistant and heat-radiating optical reflection film is formed on an outer surface of the reflector.

7. The knock light device according to claim 6, wherein a coating film having a predetermined light absorption is formed on a portion of the inner surface of the reflector that abuts with the light guide plate and in the vicinity thereof. .

[8] The device according to claim 6, wherein a region where a coating film having a predetermined light absorption is formed is formed on the outer surface of the light guide plate near the fitting portion and the Z or the fitting portion with the reflector. A backlight device, which is provided.

[9] In a sidelight type backlight device in which a light source unit is disposed on a side end surface of a light guide plate, the light source unit includes a light emitting source and a reflector, and the inner and outer surfaces of the reflector have heat radiation properties. A backlight device having a transparent coating film formed thereon.

[10] A sidelight-type backlight device including a light source unit and a light guide plate having a light incident end surface into which light from the light source unit enters, wherein the light source unit is disposed on the light incident end surface of the light guide plate. In this case, at least one of the two light guide plate side end surfaces adjacent to the light incident end surface of the light guide plate and the opposing side end surface facing the light incident end surface has light resistance and heat radiation. A backlight device having a reflective coating formed thereon.

[11] A sidelight-type backlight device including a light source unit and a light guide plate having a light incident end face through which light from the light source unit enters, wherein the light source unit is disposed on the light incident end surface of the light guide plate. In this case, at least one of the two light guide plate side end surfaces adjacent to the light incident end surface of the light guide plate and the opposite side end surface facing the light incident end surface has a heat-radiating transparent coating film. A backlight device, characterized in that a backlight is formed.

[12] A sidelight-type backlight device including a light source unit and a light guide plate having a light incident end surface through which light from the light source unit enters, wherein the light source unit is disposed on the light incident end surface of the light guide plate. In this case, a dot-like fine pattern made of an optical reflection coating film having light resistance and heat radiation is provided on a surface opposite to a light exit surface from which light incident from the light incident end surface of the light guide plate exits. And a density of the fine pattern increases as the distance from the light source increases.

[13] A sidelight-type backlight device including a light source unit and a light guide plate having a light incident end face through which light from the light source unit enters, wherein the light source unit is disposed on the light incident end surface of the light guide plate. In this case, a line-shaped fine pattern made of an optically reflective coating film having light resistance and heat radiation is provided on a surface of the light guide plate opposite to a light exit surface from which light enters from the light incident end surface. And a density of the fine pattern increases as the distance from the light source increases.

[14] A sidelight-type backlight device including a light source unit and a light guide plate having a light incident end surface through which light from the light source unit enters, wherein the light source unit is disposed on the light incident end surface of the light guide plate. In this device, the device includes a base sheet on one side of which a light-reflective and heat-radiating optical reflection coating is formed, and emits light incident from a light incident end face of the light guide plate. A backlight device, wherein an optical reflection coating film formed on the base sheet is disposed to face the surface opposite to the surface.

15. The backlight device according to claim 14, wherein a transparent film having a heat radiation property is formed on a side of the light reflection plate of the optical reflection coating.

[16] In the apparatus according to [14], a region where a coating film having a predetermined light absorption is formed is provided in the vicinity of the light-source-unit-side joint portion of the optical reflection coating film and in the vicinity thereof. A backlight device comprising:

[17] A sidelight-type backlight device including a light source unit and a light guide plate having a light incident end surface through which light from the light source unit enters, wherein the light source unit is disposed on the light incident end surface of the light guide plate. In the apparatus, a housing for accommodating the light guide plate is provided, and a light incident end face force of the light guide plate is provided on an inner surface of the housing opposed to a surface on a side opposite to a light exit surface for emitting the incident light. The backlight device according to claim 1, wherein an optical reflection coating film having light resistance and heat radiation property is formed.

18. The backlight device according to claim 17, wherein a transparent coating film having a heat radiation property is formed on the optical reflection coating film on the side of the light guide plate.

[19] The device according to claim 17, wherein a region where a coating film having a predetermined light absorption is formed is provided in a vicinity of the light-reflecting-portion-side joint portion of the optical reflection coating film and in the vicinity thereof. A backlight device comprising:

[20] A sidelight-type backlight including a light source unit and a light guide plate having a light incident end surface through which light from the light source unit enters, wherein the light source unit is disposed on the light incident end surface of the light guide plate. In the device, the light source unit includes a cold cathode tube and a reflector, and a heat radiating unit is provided at a substantially central portion in a longitudinal direction of the cold cathode tube on a light incident end face of an inner surface of the reflector. The backlight device, wherein the heat radiating portion has a higher heat radiating property than a base material of the reflector.

21. The backlight device according to claim 20, wherein the heat radiation portion is formed with an optical reflection coating having light resistance and heat radiation.

22. The backlight device according to claim 20, wherein a heat-radiating transparent coating film is formed on the heat radiating portion.

23. The knock light device according to claim 20, wherein the heat radiating portion is arranged at a position at least 20 mm away from an electrode portion of the cold cathode tube.

[24] The apparatus according to claim 20, wherein the apparatus is provided with a lamp holder for holding both ends of the light emitting source, and the optical reflection coating is formed on a surface of the lamp holder. A backlight device characterized in that:

[25] A sidelight-type backlight including a light source unit and a light guide plate having a light incident end surface through which light from the light source unit enters, wherein the light source unit is disposed on the light incident end surface of the light guide plate. In the apparatus, the light source unit includes a cold cathode tube and a reflector, and a light-receiving end face of an inner surface of the reflector substantially at a central portion in a longitudinal direction of the cold cathode tube on an end surface facing the cold cathode tube. A backlight device comprising a convex portion protruding in a directional force.

26. The backlight device according to claim 25, wherein an inner surface of the reflector including the convex portion is a metal mirror surface.

27. The backlight device according to claim 25, wherein an enhanced reflection film is provided on an inner surface of the reflector including the convex portion.

28. The backlight device according to claim 25, wherein an optical reflection coating film having light resistance and heat radiation is formed on an inner surface of the reflector including the convex portion.

29. The backlight device according to claim 25, wherein a transparent coating film having a heat radiation property is formed on an inner surface of the reflector including the convex portion.

30. The backlight device according to claim 25, wherein the convex portion is formed of an optical reflection coating having light resistance and heat radiation.

[31] The device according to claim 25, wherein the convex portion is formed of a transparent coating film having a heat radiation property. A backlight device characterized in that the backlight device is provided.

32. The apparatus according to claim 25, wherein the width of the projection is at least lmm, and the end of the projection is separated from the electrode portion of the cold cathode tube by 20 mm or more. Backlight device.

[33] In a direct-type backlight device including a lamp house and a plurality of light-emitting sources installed inside the lamp house, an optical reflection coating having light resistance and heat radiation property is formed on an inner surface of the lamp house. A backlight device, characterized in that a backlight is formed.

[34] A direct-type including a lamp house and a plurality of light sources installed inside the lamp house In this knock light device, the device is provided with a base sheet on one side of which a light-reflective and heat-radiating optical reflection coating is formed, and the optical reflection coating faces the light source. A knock light device, which is disposed inside the lamp house.

[35] In a direct-type knock light device including a lamp house and a plurality of light emitting sources installed inside the lamp house, a reflection sheet is provided on an inner surface of the lamp house, and the light emission of the reflection sheet is provided. A backlight device, wherein an optical reflection coating having light resistance and heat radiation is formed in a region directly facing the light source.

[36] A direct-type backlight device including a lamp house, a light diffusing member provided at an opening of the lamp house, and a plurality of cold cathode tubes provided inside the lamp house, A reflection sheet is provided on the inner surface of the cold cathode tube, and a heat radiation area is provided substantially at the center of the reflection surface of the inner surface facing the light diffusing member in the longitudinal direction of the cold cathode tube. The backlight device according to claim 1, wherein an optical reflection coating film having light resistance and heat radiation property is formed.

37. The backlight device according to claim 36, wherein a heat-radiating transparent coating film is formed in the heat radiation region.

38. The knock light device according to claim 36, wherein the heat radiating portion is arranged at a position separated from the electrode portion of the cold cathode tube by 20 mm or more.

[39] The apparatus according to claim 36, wherein the heat radiating region is provided corresponding to the plurality of cold cathode tubes, and the heat radiating regions are arranged at positions shifted from each other. The backlight device that is the feature.

[40] A direct-type backlight device including a lamp house, a light diffusing member installed at an opening of the lamp house, and a plurality of cold cathode tubes installed inside the lamp house, wherein the lamp house An optical reflection coating having light resistance and heat radiation is formed on the inner surface of the cold cathode fluorescent lamp, and a reflection surface of the inner surface facing the light diffusing member is substantially at a central portion in a longitudinal direction of the cold cathode tube. A backlight device comprising a heat radiation area, and an optical reflection coating having light resistance and heat radiation formed on the heat radiation area.

41. The backlight device according to claim 40, wherein a transparent coating film having heat radiation is formed in the heat radiation region.

42. The apparatus according to claim 40, wherein the heat radiating section is connected to an electrode section of the cold cathode tube.

Knock light device characterized by being located at a distance of 20 mm or more.

43. The apparatus according to claim 40, wherein the heat radiating region is provided corresponding to the plurality of cold cathode tubes, and the heat radiating regions are arranged at positions shifted from each other. The backlight device that is the feature.

[44] In a direct-type backlight device including a lamp house, a light diffusing member provided at an opening of the lamp house, and a plurality of cold cathode tubes provided inside the lamp house, At a substantially central portion in a longitudinal direction of the cold-cathode tube of the reflection surface facing the light diffusion member, a convex portion protruding toward the cold-cathode tube is provided. Backlight device.

45. The backlight device according to claim 44, wherein a reflection sheet is provided on an inner surface of the lamp house including the projection.

46. The backlight device according to claim 44, wherein an optical reflection coating having light resistance and heat radiation is formed on an inner surface of the lamp house including the convex portion.

47. The apparatus according to claim 44, wherein the width of the projection is at least lmm, and an end of the projection is separated from the cold cathode tube by an electrode force of 20 mm or more. Backlighting device.

48. The apparatus according to claim 44, wherein the projections are provided corresponding to the plurality of cold cathode tubes, and the projections are arranged at positions shifted from each other. Backlight device.

[49] In a liquid crystal display device including a sidelight type backlight device in which a light source unit is disposed on a side end surface of a light guide plate, the light source unit includes a light emitting source and a reflector, and an inner surface of the reflector has A liquid crystal display device, wherein an optical reflection coating film having light resistance and heat radiation property is formed.

[50] A liquid containing a sidelight type backlight device in which a light source unit is disposed on a side end surface of a light guide plate In the crystal display device, the light source unit includes a light emitting source and a reflector, a transparent coating film having a heat radiation property is formed on an inner surface of the reflector, and light resistance and heat radiation property are formed on an outer surface of the reflector. A liquid crystal display device, wherein an optical reflection coating having the following is formed.

[51] In a liquid crystal display device including a direct-type knock light device including a lamp house and a plurality of light-emitting sources installed inside the lamp house, an inner surface of the lamp house has light resistance and heat radiation. A liquid crystal display device, wherein an optical reflection coating having the following is formed.

[52] In a liquid crystal display device including a direct-type knock light device including a lamp house and a plurality of light-emitting sources installed inside the lamp house, the device has light resistance and heat radiation property on one surface. A liquid crystal display device, comprising: a base sheet provided with an optical reflection coating having the following formula: wherein the optical reflection coating is disposed inside the lamp house toward the light emitting source.

[53] In a liquid crystal display device including a direct-type knock light device including a lamp house and a plurality of light-emitting sources installed inside the lamp house, a reflective sheet is provided on an inner surface of the lamp house, A liquid crystal display device, wherein an optical reflection coating film having light resistance and heat radiation is formed in a region directly facing the light emitting source of the reflection sheet.

[54] A liquid crystal display including a direct-type backlight device including a lamp house, a light diffusing member installed at an opening of the lamp house, and a plurality of cold cathode tubes installed inside the lamp house. In the apparatus, a reflection sheet is provided on an inner surface of the lamp house, and a heat radiating region is provided at a substantially central portion in a longitudinal direction of the cold cathode tube on a reflection surface of the inner surface facing the light diffusing member. A liquid crystal display device, wherein an optical reflection coating having light resistance and heat radiation is formed in the heat radiation region.