JP2009162868A - Liquid crystal display device and method of forming reflective member for liquid crystal display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a liquid crystal display device which enhances directivity of a backlight and improves the efficiency of using light, and to provide a method of forming a reflective member for the liquid crystal display device. <P>SOLUTION: The liquid crystal display device includes: an illumination device having a light source K and a light guide plate 2 which diffuses light of the light source K and forms a surface light source; a liquid crystal panel 1 which is arranged opposite to the illumination device and has a liquid crystal layer; a light-condensing member 4 which is arranged between the liquid crystal panel 1 and the light guide plate 2 and has light-condensing protrusion parts 4 ml protruded toward the liquid crystal panel 1 side so as to condense the light emitted from the light source K toward the liquid crystal panel 1; and a reflective member 8 which is arranged between the light guide plate 2 and the light-condensing member 4 confronting the top 4m11 of the light condensing protrusion parts 4m1 and consists of opening parts 8a allowing the light emitted from the light source K to pass therethrough and non-opening parts 8b reflecting the light emitted from the light source K. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a liquid crystal display device used for a television, a mobile phone, and the like, and a reflection member forming method for the liquid crystal display device.

In recent years, liquid crystal display devices widely used for display of televisions, mobile phones, etc., can be thin and thin as flat panel displays compared to conventional cathode ray tube type display devices that emit electron beams. It is a big feature.
In order to further utilize this thin feature, the liquid crystal display device adopts a direct type system in which a light source that transmits light from the rear side of the conventional voltage-controlled liquid crystal panel is disposed behind the display screen G (see FIG. 8A). On the other hand, in order to further utilize the thin features recently, as shown in FIG. 8A, in the liquid crystal television 100, the light source k is arranged on both outer sides of the display screen G, and the light sources k on both outer sides are arranged. A sidelight system is used that diffuses light and guides light as a surface light source from the rear of the liquid crystal panel 101 using the light guide plate 102 (see FIGS. 9 and 8B) (light in the direction of arrow α1 in FIG. 8B). It has been adopted.
8A is a front view of a conventional liquid crystal television 100, and FIG. 8B is an enlarged sectional view taken along the line DD of FIG. 8A. FIG. 9 is an exploded enlarged perspective view showing a configuration for displaying an image on the display screen G of the conventional liquid crystal television 100 shown in FIG.

As shown in FIGS. 8A and 9, the sidelight type liquid crystal television 100 emits light emitted in a direction of an arrow α0 from a pair of light sources k disposed on both outer sides of the display screen G. After being diffused uniformly in the light guide plate 102 (see FIG. 9) and guided forward (on the front side of the paper surface of FIG. 9, the direction of the arrow α1 in FIG. 8B), the light condensing sheet 104 causes the light guide plate 102 to The diffused light has a higher directivity to the front, and the light having the enhanced directivity is diffused by the diffusion sheet 105 so as to provide a uniform backlight throughout the display screen G (see FIG. 8A). Then, the backlight is transmitted from the rear side (back side of the paper surface of FIG. 9) to the front side (front side of the paper surface of FIG. 9) of the liquid crystal panel 101, thereby displaying the display screen G (see FIG. 8A). The image is displayed.
In addition, there exists the following patent document 1 as literature well-known invention concerning this application.
JP 2006-134748 A (paragraphs 0019-0022, FIG. 2 etc.)

By the way, the above-described sidelight type liquid crystal television 100 often uses a light emitting diode as the light source k.
However, the light emission efficiency of the light emitting diode is still low at present, and the number of light emitting diodes to be used is increased in order to secure the necessary amount of light from the backlight.
Further, as shown in FIG. 9 and FIG. 8B, the light condensing sheet 104 condenses the diffused light incident from the light guide plate 102 forward, that is, toward the liquid crystal panel 101 side, and increases its luminance. In addition, a large number of semi-egg-like convex portions 104m1 are projected forward, that is, toward the liquid crystal panel 101 side.

As shown in FIG. 8B, the semi-egg-like convex portion 104m1 of the condensing sheet 104 condenses the light h101 transmitted through the vicinity of the apex portion 104m11 toward the front to increase the brightness, Due to the difference in refractive index, the light h102 directed to the location 104m10 separated from the vertex 104m11 is totally reflected again toward the light guide plate 102 at the separated location 104m10.
Due to this total reflection, the directivity of light in front, that is, the directivity of light to the liquid crystal panel 101 is reduced and the loss of light is caused, so that the light use efficiency is lowered.

Therefore, in order to compensate for the decrease in the light utilization efficiency, measures such as increasing the number of light-emitting diodes of the light source k and increasing the power consumption are necessary. New measures such as an increase in the cost of the light source k and an increase in power consumption are required. Problems arise.
In view of the above circumstances, an object of the present invention is to provide a liquid crystal display device capable of improving the directivity of a backlight and improving light utilization efficiency, and a method for forming a reflecting member of the liquid crystal display device.

  In order to achieve the above object, a liquid crystal display device according to the first aspect of the present invention is directed to a lighting device having a light source, a light guide plate that diffuses light from the light source and serves as a surface light source, and faces the lighting device. A liquid crystal panel having a liquid crystal layer, and disposed between the liquid crystal panel and the light guide plate, and projecting toward the liquid crystal panel and collecting light emitted from the light source toward the liquid crystal panel A light condensing member having a light condensing protrusion, disposed between the light guide plate and the light condensing member, facing the top of the light condensing protrusion of the light condensing member and emitting light emitted from the light source. A reflecting member having an opening for allowing passage and a non-opening for reflecting light emitted from the light source is provided.

  A liquid crystal display device according to the second aspect of the present invention includes a lighting device having a light source, a light guide plate that diffuses light from the light source to form a surface light source, and a liquid crystal layer that is disposed to face the lighting device. A liquid crystal panel; and a condensing protrusion that is disposed between the liquid crystal panel and the light guide plate and projects toward the liquid crystal panel to collect light emitted from the light source toward the liquid crystal panel. An aperture that is disposed between the light guide plate and the light condensing member and allows light having an optical path to be emitted from the light condensing member toward the liquid crystal panel. And a reflection member having a non-opening portion that reflects light having an optical path that is reflected by the outer surface of the light collecting member and is not emitted toward the liquid crystal panel among light emitted from the light source.

  A reflective member forming method for a liquid crystal display device according to a third aspect of the present invention is the reflective member forming method for a liquid crystal display device according to the first or second aspect of the present invention, and is a surface of the light collecting member on the side opposite to the liquid crystal panel. A step of applying a photocurable resin to the photocurable resin, a step of irradiating the photocurable resin applied to the light collecting member with collimated light to form a polymer, and the polymer and the photocurable resin provided Washing the light collecting member with alcohol and removing the photocurable resin; applying a highly reflective material containing a solvent to the portion of the light collecting member from which the photocurable resin has been removed; Heat-treating a light collecting member provided with a high reflectivity material including a polymer and the solvent, and evaporating the solvent to form a reflective member of the high reflectivity material.

  ADVANTAGE OF THE INVENTION According to this invention, the liquid crystal display device which can improve the directivity of a backlight and can improve the utilization efficiency of light, and the reflection member formation method of this liquid crystal display device are realizable.

Embodiments of the present invention will be described below with reference to the accompanying drawings.
<< First Embodiment >>
<Configuration of LCD TV 10>
The liquid crystal television 10 of the first embodiment to which the present invention is applied has a display screen G for displaying an image as shown in FIG. 1A of the front view, and the image is displayed on the display screen G. In this case, light is transmitted through the liquid crystal layer to which a voltage corresponding to the image is applied from the rear (back side of the paper surface in FIG. 1 (a)) to the front (front side of the paper surface in FIG. 1 (a)). The applied light is irradiated to individual pixels (not shown) of a color filter (not shown), and the image is displayed by causing each pixel to display a color corresponding to the image.
1B is an enlarged cross-sectional view taken along the line AA in FIG. 1A, and FIG. 1C is an enlarged cross-sectional view taken along the line BB in FIG. FIG. 2 is an exploded enlarged perspective view showing a configuration for displaying an image on the display screen G of the liquid crystal television 10 shown in FIG.

  As shown in FIGS. 1 and 2, the liquid crystal television 10 has a configuration in which an image is displayed on a display screen G. A liquid crystal layer to which a voltage corresponding to the image is applied and a pixel that develops color by light transmitted through the liquid crystal layer. A liquid crystal panel 1 having a color filter, and light emitting diodes (LEDs) (not shown) that are disposed on both sides of the display screen G and are mounted on a circuit board. A pair of light source modules K that emit light in the direction of arrow α 0, a light guide plate 2 that guides light from the light source module K, and a light guide plate 2 that is printed on the back surface of the light guide plate 2 and guides the light in the light guide plate 2. The white printed dot pattern for guiding the light forward as shown by the arrow α1 (see FIGS. 1B and 1C) by diffusively reflecting the reflected light, the back side of the light guide plate 2 (the paper surface of FIG. 2) Deviated from the total reflection condition of the light guide plate 2 disposed on the back side) Reflected by the reflective sheet 3 for diffusely reflecting the light escaping to the back side to make it light in the front direction (in the direction of arrow α1 in FIGS. 1B and 1C), or by the white printed dots or reflected by the reflective sheet 3 The light that has passed through the light guide plate 2 such as the collected light is focused in the front direction (in the direction of arrow α1 in FIGS. 1B and 1C) to increase the front brightness, and the light is collected by the light collecting sheet 4. And a diffusion sheet 5 that diffuses light in which luminance unevenness such as glare is generated and diffuses light that is visually good in quality.

In addition, although the case where there is one diffusion sheet 5 is illustrated, the number of the diffusion sheets 5 is not limited to one and can be arbitrarily selected.
Here, the light source module K that is a light source and the light guide plate 2 that guides light from the light source module K irradiates the liquid crystal panel 1 with light, and are therefore referred to as illumination devices.

<Light guide plate 2>
Incidentally, as indicated by an arrow α 0 in FIG. 2, the light emitted from the light source module K which is a light source and incident on the light guide plate 2 is spread in the light guide plate 2 by being totally reflected, It is emitted toward the liquid crystal panel 1 in the direction of the arrow α1 in FIGS. 1B and 1C by being scattered and reflected by the white dots printed on the back surface 2u (see FIGS. 1B and 1C). .
In order to equalize the light from the light guide plate 2 toward the liquid crystal panel 1 in the front direction (the direction of the arrow α1 in FIGS. 1B and 1C) in the plane, the diameter of the white dots increases toward the center. A large number of white ink is formed by screen printing so as to gradually increase.

For example, the white dots 7a on the scattering reflection surface 7 on the side end side of the light guide plate 2 shown in FIG. 2 have a small diameter, and the white dots 7b on the scattering reflection surface 7 on the center side of the light guide plate 2 have a large diameter. .
As a result, the reflectance on the back surface 2u (FIGS. 1B and 1C) side of the light guide plate 2 is low on the side end portion where the light is strong and close to the light source module K, and the light from the light source module K gradually increases. The light is gradually increased toward the weakening center side, and light emitted from the light guide plate 2 toward the liquid crystal panel 1 (light in the direction indicated by the arrow α1 in FIGS. 1B and 1C) is made uniform.
The scattering reflection surface 7 may be formed by a method other than printing using white ink as long as a white dot or the like having a high reflectance is formed. If the reflectance gradually increases toward the center, shapes other than dots can be selected as the scattering reflection surface 7. Alternatively, it may be a conical groove.

<Condensing sheet 4>
As shown in FIGS. 2 and 1, the light from the light guide plate 2 is condensed toward the front, that is, toward the liquid crystal panel 1 (in the direction of the arrow α1 in FIGS. 1B and 1C) to increase the front luminance. For this reason, on the surface 4m on the liquid crystal panel 1 side of the light collecting sheet 4 on which light is incident from the light guide plate 2, a half-egg-like half-egg-like convex part 4m1 ( 2) (see FIG. 2) and a large number of them are projected toward the front (see FIGS. 1B and 1C).
Here, the semi-egg-like convex portion 4m1 formed on the surface 4m of the light collecting sheet 4 has the highest apex portion 4m11 located at the center thereof, that is, is formed to protrude toward the liquid crystal panel 1 side.

  On the other hand, as shown in FIG. 2, FIG. 1B and FIG. 1C, the back surface 4 u of the light collecting sheet 4 (see FIGS. 1B and 1C), that is, the light guide plate 2 side of the light collecting sheet 4. The surface of the condensing sheet 4 is located at a position facing the apex 4m11 of the semi-egg-like convex part 4m1 of the surface 4m of the condensing sheet 4, corresponding to each semi-egg-like convex part 4m1. A reflection layer 8 having an opening pattern 8a substantially the same shape as the apex 4m11 is formed by vapor deposition as an aluminum metal pattern.

As shown in FIGS. 1B and 1C, the light-condensing sheet 4 having the reflection layer 8 formed on the back surface 4u, and the light guide plate 2 having the scattering reflection surface 7 such as white dots formed on the back surface 2u. Are joined by connecting the reflective layer 8 of the light collecting sheet 4 and the surface 2m of the light guide plate 2 via an adhesive layer 9 of a transparent adhesive layer, for example, a transparent elastomer double-sided tape.
That is, the adhesive layer 9 which is a transparent adhesive layer is attached to the surface 2m of the light guide plate 2 on which the white dot scattering reflection surface 7 is formed by screen printing on the back surface 2u of the light guide plate 2, and the reflection layer 8 is the back surface. The condensing sheet 4 patterned in 4u is pasted through an adhesive layer 9 which is a transparent adhesive layer.

<Formation of Reflective Layer 8 of Condensing Sheet 4 and Joining Method of Condensing Sheet 4 and Light Guide Plate 2>
Next, a method for forming the reflective layer 8 on the back surface 4 u of the light collecting sheet 4 and a method for joining the light collecting sheet 4 and the light guide plate 2 will be described with reference to FIGS. 3 and 4. 3 and 4 are diagrams showing a process of forming the reflective layer 8 of the light collecting sheet 4 and a process of joining the light collecting sheet 4 and the light guide plate 2.
Here, a case where the reflective layer 8 of the light collecting sheet 4 is formed using magnesium oxide will be described as an example.
First, as shown in FIG. 3A, a photocurable resin monomer m is applied to the back surface 4 u which is a non-lens surface of the light collecting sheet 4. Here, an acrylic resin is suitable as the photocurable resin.

Subsequently, as shown in FIG. 3B, when collimated light C, which is light that travels straight from the surface 4m side on the lens surface side of the condensing sheet 4, is irradiated, the monomer m of the photocurable resin is specified by the lens effect. Light gathers in the region, and only this portion becomes the polymer p and is cured. Here, since the acrylic resin is used as the monomer m of the photocurable resin, the polymer p in the cured portion is transparent.
For the collimated light C to be irradiated, a high pressure mercury lamp or a metal halide lamp can be used.

Subsequently, as shown in FIG. 3C, a photocurable resin monomer m and polymer p formed on the back surface 4u of the non-lens surface of the light collecting sheet 4 shown in FIG. The monomer m of the photo-curable resin is removed by washing with.
Subsequently, as shown in FIG. 4A, a high reflectance material 8z dissolved in a solvent is applied to the portion where the monomer m of the photocurable resin is removed.
Here, the material 8z having high reflectivity is optimally prepared by mixing magnesium oxide powder in a binder and dissolving it in a solvent. Next, by performing a heat treatment, the solvent in the high reflectivity material 8z is evaporated, and the reflective layer 8 is formed.

  Subsequently, as shown in FIG. 4 (b), a thin double-sided adhesive tape 9 t is attached to the light guide plate 2. Here, an acrylic resin is optimal for the double-sided adhesive tape 9t. Next, the polymer p and the reflective layer 8 are formed on the back surface 4u of the light collecting sheet 4 created in the steps of FIGS. 3 (a) to 4 (a) on the double-sided adhesive tape 9t attached to the light guide plate 2. The sheet is pasted and bonded to the light guide plate 2 having the scattering reflection surface 7 formed on the back surface 2u with the adhesive layer 9 of the double-sided tape 9t.

<Effect>
According to the above configuration, as shown in FIGS. 1B and 1C, the light h11 traveling from the light guide plate 2 toward the apex 4m11 of the semi-egg-like convex portion 4m1 of the light collecting sheet 4 is reflected on the reflection layer 8. The aperture pattern 8 a passes through the condensing sheet 4 and can be emitted toward the liquid crystal panel 1.
On the other hand, light h12 (for example, FIG. 8 (b) shown in FIG. 8 (b) is directed to a location 4m10 away from the apex portion 4m11 of the semi-egg-like convex portion 4m1 of the light collecting sheet 4 and proceeds as it is. Light h102) is reflected by the non-opening 8b of the reflective layer 8 and returns into the light guide plate 2, but after being reflected on the back surface 2u side of the light guide plate 2, it passes through the opening pattern 8a of the reflective layer 8. The light passes through the condensing sheet 4 and can be emitted from the apex 4m11 toward the liquid crystal panel 1.

As described above, the reflection layer 8 which is a reflection portion having the opening pattern 8 a is provided between the light guide plate 2 and the light collecting sheet 4, and light in an oblique direction out of the light emitted from the light guide plate 2 is reflected on the reflection layer 8. Since the opening pattern 8a is allowed to pass through after being reflected by the non-opening portion 8b, light can be efficiently collected and condensed forward.
Therefore, high directivity in the front direction of the backlight (in the direction of the arrow α1 in FIGS. 1B and 1C) can be obtained by the sidelight method. Therefore, light can be efficiently emitted from the light collecting sheet 4 in the front direction, and the front luminance is increased.
Thereby, when obtaining the same luminance in front of the light collecting sheet 4, the light output of all the light source modules K is reduced by the amount of light emitted obliquely. Therefore, the number of light emitting diodes of the light source module K can be reduced, and the light source cost is reduced.

Further, since the front luminance increases, the power of the backlight can be reduced, and the accompanying increase in temperature can be suppressed. For example, a large monitor has a large power consumption due to its large size, but can reduce power consumption. In addition, it is possible to reduce the power consumption of mobile devices such as mobile phones and PDAs (Personal Digital Assistants) that are driven by batteries and require low power consumption.
In the present embodiment, the reflective layer 8 has been described by exemplifying a metal pattern using aluminum, but it is also possible to use a metal having a high regular reflectance other than aluminum.

<< Second Embodiment >>
Next, a second embodiment will be described with reference to FIG. 5A is an enlarged cross-sectional view taken along line AA of FIG. 1A of the second embodiment, and FIG. 5B is a cross-sectional view of FIG. 1A of FIG. It is a B line section enlarged view.
As shown in FIG. 5, the liquid crystal television of the second embodiment includes a reflective layer 8 having an opening pattern 8a provided on the back surface 4u of the light collecting sheet 4 of the first embodiment shown in FIGS. Is provided as a reflective layer 28 having an opening pattern 28 a on the surface 22 m of the light guide plate 22.
Since the configuration other than this is the same as that of the first embodiment, the same components as those of the first embodiment are denoted by reference numerals in the twenty-seventh order, and detailed description thereof is omitted.

In the second embodiment, as shown in FIGS. 2 and 5, the liquid crystal of the light condensing sheet 24 is used to condense light from the light guide plate 22 toward the front, that is, toward the liquid crystal panel 21 side to increase luminance. A large number of half-oval-like convex portions 24m1 cut in half in the short direction are provided on the surface 24m on the panel 21 side so as to protrude toward the front, that is, toward the liquid crystal panel 21 side. .
The apex portion 24m11 located at the center of the half-oval shaped convex portion 24m1 is the highest, that is, protrudes toward the liquid crystal panel 21 side.
On the other hand, as shown in FIG. 5, on the surface 22m of the light guide plate 22, that is, on the surface of the light guide plate 22 on the liquid crystal panel 21, the apex 24m11 of the semi-egg-like convex portion 24m1 of the surface 24m of the light collecting sheet 24 is formed. A reflective layer 28 having an opening pattern 28a having substantially the same shape as the apex 24m11 of the half-egg-like convex part 24m1 corresponding to each half-oval-like convex part 24m1 is deposited by vapor deposition as an aluminum metal pattern. Is formed.

As shown in FIG. 5, a condensing sheet 24 having a semi-egg-like convex portion 24m1 formed on the surface 24m and a reflective layer 28 having an opening pattern 28a are formed on the surface 22m and a scattering reflection surface such as white dots. 27 is bonded to the light guide plate 22 formed on the back surface 22u via a transparent adhesive layer, for example, an adhesive layer 29 of a transparent elastomer double-sided tape.
According to the above configuration, as shown in FIG. 5, the light h <b> 21 from the light guide plate 22 toward the apex 24 m <b> 11 of the light collecting sheet 24 passes through the opening pattern 28 a of the reflective layer 28 and passes through the light collecting sheet 24. Then, it can be emitted toward the liquid crystal panel 21.

On the other hand, light h22 (for example, FIG. 8 (b) shown in FIG. 8 (b) is directed to a location 24m10 away from the apex portion 24m11 of the semi-egg-like convex portion 24m1 of the light collecting sheet 24 and proceeds as it is. Light h102) is reflected by the non-opening portion 28b of the reflective layer 28 and returns into the light guide plate 22, but after being reflected on the back surface 22u side of the light guide plate 22, it passes through the opening pattern 28a of the reflective layer 28. The light passes through the condensing sheet 24 and can be emitted from the apex 24m11 toward the liquid crystal panel 21.
In this way, the aluminum reflective layer 28 having the opening pattern 28a is formed on the surface 22m of the light guide plate 22, and the condensing sheet 24 is pasted thereon using the transparent adhesive layer 29 which is a transparent adhesive layer. It is also possible to configure, and the effects of the first embodiment are similarly achieved.

<< Third Embodiment >>
Next, a third embodiment will be described with reference to FIG. 6A is an enlarged sectional view taken along line AA in FIG. 1A of the third embodiment, and FIG. 5B is a cross-sectional view taken along line B- in FIG. 1A of the third embodiment. It is a B line section enlarged view.
As shown in FIG. 6, in the third embodiment, the reflective layer 28 formed of an aluminum metal pattern on the surface 22m of the light guide plate 22 of the second embodiment shown in FIG. The surface 38 is formed.

The diffuse reflection printing surface 38 having the opening pattern 38a of the third embodiment is formed by printing on the surface 32m of the light guide plate 32 using white ink or the like having a high diffuse reflectance. Note that the diffuse reflection printing surface 38 may be formed by a method other than printing using white ink or the like having a high diffuse reflectance, and if the diffuse reflectance is high, a color other than white may be used.
Since the configuration other than this is the same as that of the second embodiment, the same components are denoted by reference numerals in the thirty range and detailed description thereof is omitted.
According to the above configuration, as shown in FIG. 6, the light h31 traveling from the light guide plate 32 toward the apex 34m11 of the semi-egg-like convex portion 34m1 of the light collecting sheet 34 passes through the opening pattern 38a of the reflective layer 38. Then, the light passes through the light collecting sheet 34 and can be emitted toward the liquid crystal panel 31.

On the other hand, the light h32 (for example, FIG. 8 (b) shown in FIG. 8 (b)) is directed to the portion 34m10 separated from the apex portion 34m11 of the semi-egg-like convex portion 34m1 of the light collecting sheet 34. ) Light h102) is reflected by the non-opening portion 38b formed of white ink on the diffuse reflection printing surface 38 and returns to the inside of the light guide plate 32, but after being reflected on the back surface 32u side of the light guide plate 32, The light passes through the opening pattern 38a of the diffuse reflection printing surface 38, passes through the condensing sheet 34, and can be emitted toward the liquid crystal panel 31 from the apex 34m11.
Thus, unlike the second embodiment, a reflective layer pattern may be formed on the surface 32m of the light guide plate 32 by the diffuse reflection printing surface 38, and the effects of the second embodiment are similarly achieved.
In the first to third embodiments, the case where a scattering reflection surface such as a white dot (see FIGS. 1B, 1C, and 2) is formed on the back surface of the light guide plate is described as an example. It is also possible to configure without forming the scattering reflection surface 7 on the back surface of the light guide plate.

<< Fourth Embodiment >>
Next, a fourth embodiment will be described with reference to FIG. 7A is an enlarged cross-sectional view taken along the line AA of FIG. 1A of the fourth embodiment, and FIG. 7B is a cross-sectional view of FIG. 1A of FIG. It is a B line section enlarged view.
As shown in FIG. 7, the fourth embodiment is a reflection formed by vapor deposition as a metal pattern of aluminum on the back surface 4u of the light collecting sheet 4 of the first embodiment shown in FIGS. The layer 8 is formed as a diffuse reflection printing surface 48 by printing using white ink or the like having a high diffuse reflectance. The diffuse reflection printing surface 48 has an opening pattern 48a and a non-opening 48b, as in the first embodiment.

Further, as shown in FIG. 7B, in order to reflect the light in the light guide plate 42, the back side 42u of the light guide plate 42 is centered in the left-right direction of the display screen G (the left-right direction of the paper surface of FIG. 1). A concave diffuse reflection pattern 42p having a triangular cross section, the depth of which gradually increases with time, is formed.
Due to the concave diffuse reflection pattern 42p (see FIG. 7B) formed on the back surface 42u of the light guide plate 42, the reflectance of the back surface 42u of the light guide plate 42 gradually increases from the side end toward the center. ing.

The diffuse reflection pattern 42p may be formed by injection molding together with the light guide plate 42 when the light guide plate 42 is formed, or may be formed by additional processing after the light guide plate 42 is formed.
As shown in FIG. 7, a transparent adhesive layer 49, which is a transparent adhesive layer, is attached to the front surface 42m of the light guide plate 42 having the concave diffuse reflection pattern 42p formed on the back surface 42u, and the diffuse reflection printing surface 48 is formed. The printed condensing sheet 44 is affixed. Since the other configuration is the same as that of the first embodiment, the same constituent elements as those of the first embodiment are denoted by reference numerals in the fortieth range. Detailed description will be omitted.

According to the above configuration, as shown in FIG. 7, the light h <b> 41 from the light guide plate 42 toward the apex 44 m <b> 11 of the light collecting sheet 44 passes through the opening pattern 48 a of the diffuse reflection printing surface 48 and enters the light collecting sheet 44. Can be emitted toward the liquid crystal panel 41.
On the other hand, the light h42 (for example, FIG. 8 (b) shown in FIG. 8 (b)) is directed to the location 44m10 separated from the apex portion 44m11 of the semi-egg-like convex portion 44m1 of the light collecting sheet 44. ) Light h102) is reflected by the non-opening portion 48b of the diffuse reflection printing surface 48 before returning to the inside of the light guide plate 42, but is reflected by the concave diffuse reflection pattern 42p on the back surface 42u side of the light guide plate 42, etc. Thereafter, the light passes through the opening pattern 48a of the diffuse reflection printing surface 48, passes through the condensing sheet 44, and can be emitted toward the liquid crystal panel 41 from the apex 44m11.

In this way, the diffuse reflection printing surface 48 is formed on the back surface 44u of the light collecting sheet 44, the diffusion reflection printing surface 48 is the adhesive layer 49 of the transparent adhesive layer, and the injection molding pattern 42p and the scattering reflection surface 47 are formed on the back surface 42u. You may affix on the formed light-guide plate 42, and there exists the effect of 1st Embodiment similarly.
Also, as shown in FIGS. 1 and 2, in the liquid crystal television 40, a pair of light source modules K are disposed on both sides, so light emitted from the light source modules K on both sides and traveling in the light guide plate 42. The light intensity gradually decreases as it goes from the side end side to the center side, but the concave diffuse reflection pattern 42p and the scattering gradually increase in reflectance from the end side toward the center side on the back surface 42u of the light guide plate 42. Since the reflection surface 47 is formed, it is possible to suppress a decrease in the amount of light and make it uniform.

As the shape of the concave diffuse reflection pattern 42 of the light guide plate 42, any shape such as a curved surface may be selected as long as the reflectance toward the liquid crystal panel 41 is good.
Moreover, although the case where the scattering reflection surface 47 such as a large number of white dots having a high reflectance whose diameter gradually increases from the side end portion side to the center side is formed on the back surface 42u of the light guide plate 42, A configuration without forming the scattering reflection surface 47 is also possible.

<< Other Embodiments >>
In the first to fourth embodiments, as shown in FIG. 2, the surface 4 m of the light collecting sheet 4 is exemplified as having a large number of half-oval shaped convex portions 4 m 1. For example, the condensing sheet 4 other than the portion 4m1 has a directivity toward the liquid crystal panel 1 of the backlight. For example, the surface 4m (see FIG. 2) of the condensing sheet 4 has a top portion that protrudes toward the liquid crystal panel 1. In the case where a configuration is formed that has a cross section projecting in a shape and extends continuously or intermittently in the lateral direction of the display screen G (the vertical direction of the paper surface of FIG. 1A), the reflective layer 8 The opening pattern 8a is formed in a shape that faces the top of the surface 4 of the light collecting sheet 4 and that extends continuously or intermittently in the short direction of the display screen G.

  The present invention corresponds to various condensing sheets having condensing protrusions having a cross section that protrudes in a convex shape toward the liquid crystal panel 1 other than those exemplified above, and an opening pattern and a non-opposing surface facing the top. By applying a reflective member such as a reflective layer having an opening, it can be widely used.

(a) is a front view of the liquid crystal television of the first embodiment, (b) is a cross-sectional enlarged view taken along line AA of (a), and (c) is a cross-sectional view taken along line B- of FIG. It is a B line section enlarged view. It is a disassembled expansion perspective view which shows the structure which displays an image | video on the display screen of the liquid crystal television shown to Fig.1 (a). It is a figure which shows the formation process of the reflection layer of a condensing sheet, and the joining process of a condensing sheet and a light-guide plate. It is a figure which shows the formation process of the reflection layer of a condensing sheet, and the joining process of a condensing sheet and a light-guide plate. (a) is the sectional view on the AA line of FIG. 1 (a) of 2nd Embodiment, (b) is the sectional view on the BB line of FIG. 1 (a) of 2nd Embodiment. is there. (a) is the sectional view on the AA line of FIG. 1 (a) of 3rd Embodiment, (b) is the sectional view on the BB line of FIG. 1 (a) of 3rd Embodiment. is there. (a) is the sectional view on the AA line of FIG. 1 (a) of 4th Embodiment, (b) is the sectional view on the BB line of FIG. 1 (a) of 4th Embodiment. is there. (a) is a front view of the conventional liquid crystal television, (b) is a DD line sectional enlarged view of (a). It is a disassembled expansion perspective view which shows the structure which displays an image | video on the display screen of the conventional liquid crystal television shown to Fig.8 (a).

Explanation of symbols

1, 21, 31, 41 ... liquid crystal panel,
2, 22, 32, 42 ... light guide plate (illumination device),
4, 24, 34, 44 ... Light collecting sheet (light collecting member),
4m1, 24m1, 34m1, 44m1 ... Hemi-oval shaped convex part (condensing protrusion),
4m11, 24m11, 34m11, 44m11 ... apex (top),
7, 27, 37, 47 ... scattering reflection surface (scattering reflection part),
8, 28 ... reflective layer (reflective member),
8a, 28a, 38a, 48a ... opening pattern (opening),
8b, 28b, 38b, 48b ... non-opening,
8z ... High reflectivity material 10, 40 ... Liquid crystal television (liquid crystal display device),
9t ... Double-sided adhesive tape 38, 48 ... Diffuse reflection printing surface (reflection member),
42p ... Diffuse reflection pattern (scattering reflection part),
C ... Collimated light K ... Light source module (light source, lighting device)
m: Monomer (photo curable resin)
p ... polymer

Claims (10)

An illumination device having a light source and a light guide plate that diffuses light from the light source to form a surface light source;
A liquid crystal panel disposed opposite to the illumination device and having a liquid crystal layer;
A condensing member that is disposed between the liquid crystal panel and the light guide plate and has a condensing protrusion that projects toward the liquid crystal panel and condenses light emitted from the light source toward the liquid crystal panel; With
An opening that is disposed between the light guide plate and the light condensing member, opposes the top of the light condensing protrusion of the light condensing member, and reflects light emitted from the light source while allowing light emitted from the light source to pass therethrough. A liquid crystal display device comprising: a reflecting member having a non-opening portion. An illumination device having a light source and a light guide plate that diffuses light from the light source to form a surface light source;
A liquid crystal panel disposed opposite to the illumination device and having a liquid crystal layer;
A condensing member that is disposed between the liquid crystal panel and the light guide plate and has a condensing protrusion that projects toward the liquid crystal panel and condenses light emitted from the light source toward the liquid crystal panel; With
An opening that is disposed between the light guide plate and the light collecting member and that passes through the light having an optical path emitted from the light collecting member toward the liquid crystal panel out of the light emitted from the light source and emitted from the light source. A liquid crystal display device comprising: a reflective member having a non-opening portion that reflects light having an optical path that is reflected on an outer surface of the light collecting member and is not emitted toward the liquid crystal panel. 3. The liquid crystal display device according to claim 1, wherein the reflecting member is provided on a surface of the light collecting member on the light guide plate side or on a surface of the light guide plate on the light collecting member side. The liquid crystal display device according to claim 1, wherein the reflection member is formed using metal or ink. 5. The scattering reflection portion that gradually increases in reflectance as it goes from both side end portions to the central portion is provided on the surface of the light guide plate on the side opposite to the liquid crystal panel. 6. The liquid crystal display device according to one item. It is the reflective member formation method of the liquid crystal display device as described in any one of Claims 1-5,
Applying a photocurable resin to the surface of the light collecting member on the side opposite to the liquid crystal panel;
Irradiating the photocurable resin applied to the light collecting member with collimated light to create a polymer; and
Washing the light-collecting member provided with the polymer and the photocurable resin with alcohol, and removing the photocurable resin;
Applying a high-reflectance material containing a solvent to the portion from which the photocurable resin of the light collecting member has been removed;
Heat-treating a condensing member provided with a high-reflectivity material containing the polymer and the solvent, evaporating the solvent, and forming a reflective member made of the high-reflectivity material. Reflective member forming method. The method for forming a reflecting member for a liquid crystal display device according to claim 6, further comprising a step of connecting the light collecting member on which the polymer and the reflecting member are formed with a light guide plate through a double-sided adhesive tape. The method for forming a reflective member for a liquid crystal display device according to claim 6, wherein the photocurable resin is an acrylic resin. The method for forming a reflective member for a liquid crystal display device according to claim 6, wherein the high reflectance material is magnesium oxide. The method for forming a reflective member for a liquid crystal display device according to claim 7, wherein the double-sided pressure-sensitive adhesive tape is an acrylic resin.

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