JP2002098958A - Liquid crystal device and sheet for the liquid crystal device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain luminance uniform in a screen which has no uneven luminance in a liquid crystal device with a sidelight type backlight. SOLUTION: The surface of a sheet 101, counterposed to LEDs(light-emitting diodes) 12 arranged so as to cover the LEDs 12 of the backlight, is provided with white regions 9, where a PET(polyethylene terephthalate) film 5 is exposed and black regions where light-shielding layers 8 are formed at positions corresponding to the LEDs 12. In this way, by making the surface counterposed to the LEDs 12 have a plurality of regions with respectively different light reflectance, generation of uneven brightness is prevented in the vicinity of the LEDs of the backlight and the liquid crystal device having luminance uniform in the screen without any uneven luminance is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention belongs to the technical field of a liquid crystal device, and more particularly to the technical field of a light shielding sheet arranged corresponding to a light source of a backlight interposed between a liquid crystal panel and a backlight.

[0002]

2. Description of the Related Art A liquid crystal device mainly comprises a liquid crystal panel and a backlight for irradiating the liquid crystal panel with light. The liquid crystal panel is configured by sandwiching a liquid crystal layer between a counter substrate and a TFT array substrate. A backlight, specifically a sidelight-type backlight, is disposed adjacent to a liquid crystal panel and has a light guide plate having substantially the same size as the liquid crystal panel, and an L as a light source disposed at an end of the light guide plate.
It mainly comprises an ED (light emitting element). The light guide plate is LE
The light from D is used to guide and diffuse the light, and the light diffused by the light guide plate is applied to the liquid crystal panel as a surface light source.

The liquid crystal panel and the light guide plate of the backlight are:
For example, it is adhesively fixed by a double-sided adhesive tape provided at the four corners of the outer peripheral portion. Furthermore, LED for liquid crystal panel
In order to prevent light from leaking from the LCD panel, a light shielding tape is provided between the liquid crystal panel and the backlight at a position corresponding to the LED. The surface of the light-shielding tape on the liquid crystal panel side is black. On the other hand, the surface of the light-shielding tape on the backlight side has a white color, and light from the LED is reflected and used effectively.

[0004]

However, in the above-described liquid crystal device, luminance unevenness may occur near the light source, which deteriorates the display characteristics of the liquid crystal device.

SUMMARY OF THE INVENTION The present invention has been made to solve such a problem, and it is an object of the present invention to provide a liquid crystal device which prevents the occurrence of luminance unevenness near a light source and has a uniform luminance in a plane and a liquid crystal device used therefor. The purpose is to provide a sheet.

[0006]

In order to solve such a problem, the present invention employs the following configuration.

A liquid crystal device according to the present invention comprises: a liquid crystal panel having a liquid crystal sandwiched between a first substrate and a second substrate; and a light guide plate disposed adjacent to the liquid crystal panel on the first substrate side. A backlight having a light source arranged along the end surface of the light guide plate; and a first surface and a second surface arranged at least corresponding to the light source between the backlight and the liquid crystal panel. Wherein the first surface is located on the liquid crystal panel side, the second surface is located on the backlight side, and the second surface has a light reflectance. Characterized by having a plurality of different regions.

According to such a configuration of the present invention, by providing a plurality of regions having different light reflectivities on the second surface of the sheet, light from a light source is reflected in a region having a high light reflectivity, and Light from a light source is absorbed in a region having a low reflectance. Therefore, by adjusting the light reflectance distribution on the second surface of the sheet according to the state of uneven brightness near the light source of the sidelight type backlight, occurrence of uneven brightness is prevented, and uniform brightness in the surface is reduced. Liquid crystal device having the same can be obtained.

Further, a light-shielding layer is formed on the first surface. According to such a configuration, the light-shielding layer on the first surface can shield light leaked from the light source to the liquid crystal panel, and the sheet can also function as a light-shielding sheet.

Further, the plurality of regions having different light reflectivities include a first region corresponding to the light source and a second region having a higher light reflectivity than the first region. I do. In general, the brightness of an area close to the light source tends to be bright, and therefore, the second surface of the sheet is set to the first surface corresponding to the light source.
By making the light reflectivity of the region of the second region lower than the light reflectivity of the other second region, it is possible to prevent the occurrence of uneven brightness.

Further, the second region is made of white. According to such a configuration, since white is a color having a high light reflectance, light from a light source can be effectively used. The first region is made of black or gray. As described above, the light reflectance can be reduced by making the color black or gray.

Further, a light shielding layer is formed in the first region. As described above, by providing the light-shielding layer, light is absorbed by the light-shielding layer, and the light reflectance can be reduced.

Further, the sheet has a substantially rectangular shape, and the sheet has a specifying means for specifying an arbitrary corner of the rectangle. Further, the specification means is a notch formed at an arbitrary corner of the sheet. In this way, by providing the specifying means for specifying an arbitrary corner, the appropriate position of the sheet can be easily recognized. For example, when the light reflectance distribution on the second surface of the sheet is asymmetric, the provision of the specifying means allows the sheet to be easily incorporated into the liquid crystal device at an appropriate position, thereby improving workability.

A sheet for a liquid crystal device according to the present invention is a sheet for a liquid crystal device having a base material having a first surface and a second surface, wherein the second surface has a plurality of light reflectances different from each other. It has a region. According to such a configuration of the present invention, by incorporating the liquid crystal device sheet into the liquid crystal device, a liquid crystal device without uneven brightness can be obtained.

Further, the sheet for a liquid crystal device of the present invention comprises a first sheet.
And a low-reflection layer having a light reflectance lower than the light reflectance of the substrate partially formed on the second surface. And According to such a configuration of the present invention, a plurality of regions having different light reflectivities can be formed on the second surface, and by incorporating the liquid crystal device sheet into the liquid crystal device, the liquid crystal device having no luminance unevenness can be formed. Can be obtained.

Further, the base material is made of white. According to such a configuration, since white is a color having a high light reflectance, light from a light source can be effectively used by incorporating a liquid crystal device sheet into the liquid crystal device.

Further, the base material is made of polyethylene terephthalate. Thus, polyethylene terephthalate (PET) can be used as the substrate. Further, the low reflection layer is a black layer. As described above, a black layer can be used as the low reflection layer, and light is absorbed by the black layer.

[0018] The light-emitting device may further include a light-shielding layer formed on the first surface of the substrate. According to such a configuration, the liquid crystal device sheet also has a function as a light shielding sheet for shielding light leaked from the light source to the liquid crystal panel when incorporated in the liquid crystal device.

Further, a first adhesive layer formed on a surface of the light-shielding layer opposite to a surface in contact with the substrate and a second adhesive layer formed on a second surface of the substrate are further provided. It is characterized by having. According to such a configuration, when the liquid crystal device sheet is incorporated in the liquid crystal device, the liquid crystal panel and the backlight can be fixed by the first adhesive layer and the second adhesive layer.

A first release sheet formed on a surface of the first adhesive layer opposite to a surface in contact with the light shielding layer;
It is characterized by further comprising a second release sheet formed on a surface of the second adhesive layer, which is in contact with the substrate in contact with the base material. Thus, the first release sheet and the second release sheet can be provided so as to be separated from each other so as to cover the first adhesive layer and the second adhesive layer, respectively.

Further, the sheet for a liquid crystal device has a substantially rectangular shape, and the sheet for a liquid crystal device has a specifying means for specifying an arbitrary corner of the rectangle. Further, the specification means is a notch formed at an arbitrary corner of the sheet. In this way, by providing the specifying means for specifying an arbitrary corner, the appropriate position of the sheet can be easily recognized. For example, the second sheet
In the case where the light reflectance distribution on the surface is asymmetric, the sheet can be easily incorporated into the liquid crystal device at an appropriate position by providing the specifying means, and the workability is good.

[0022]

Embodiments of the present invention will be described below with reference to the drawings. (Structure of Liquid Crystal Device Sheet) A liquid crystal device sheet according to an embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a sectional view of a sheet 1 for a liquid crystal device. FIG.
3 is a plan view of a sheet 101 constituting the liquid crystal device sheet 1. FIG. FIG. 2A is a plan view of a sheet in a state in which a release sheet, which will be described later, has been peeled from the liquid crystal device sheet when viewed from the first surface side. FIG. 2B is a plan view of the sheet in a state where a release sheet to be described later is peeled off from the liquid crystal device sheet when viewed from the second surface side. The liquid crystal device sheet is a sheet arranged corresponding to a light source constituting a part of a backlight when the liquid crystal device is used.

As shown in FIG. 1, a liquid crystal device sheet 1
Has a structure in which the first release sheet 2 and the second release sheet 7 are arranged so as to sandwich the sheet 101. The sheet 101 has a first surface 101a and a second surface 101b, and a first release sheet 2 that can be separated adjacent to the first surface 101a is disposed, and is adjacent to the second surface 101b. The second release sheet 7 which can be separated from the second release sheet 7 is disposed.

The sheet 101 is made of white PE as a base material.
T (polyethylene terephthalate) film 5 and PE
A light-shielding layer 4 made of a black material printed entirely on one surface of the T film 5 and a low reflection made of a black material partially printed on a surface of the PET film 5 facing the surface on which the light-shielded layer 4 is formed. A light-shielding layer 8 as a layer, a first adhesive layer 2 formed on a surface of the light-shielding layer 4 that faces the PET film, and a surface of the PET film 5 that faces the surface on which the light-shielding layer 4 is formed. And the second adhesive layers 6 formed on both ends of the second adhesive layer. The liquid crystal device is used in a state of the sheet 101 from which the first release sheet 2 and the second release sheet 7 are peeled off.

As shown in FIG. 2A, the sheet 101 has a black color because the light-shielding layer 4 is formed on the first surface. When the sheet 101 is incorporated in the liquid crystal device, the first surface is arranged on the liquid crystal panel side,
Light leakage from the light source to the liquid crystal panel can be prevented.

On the other hand, the second surface of the sheet 101 is made of PET.
White area 9 as a second area where film 5 is exposed
And a black region 16 as a first region where the light shielding layer 8 is formed. The white region 9 has a higher light reflectance than the black region 16. By incorporating such a sheet 101 into a liquid crystal device such that a surface having a plurality of regions having different light reflectances is positioned on the light source side of the backlight,
It is possible to prevent luminance unevenness occurring near the light source. That is, by changing the distribution of a plurality of regions having different light reflectances on the first surface of the sheet 101 according to the state of uneven brightness near the light source of the liquid crystal device, it is possible to obtain a liquid crystal device with uniform brightness in the surface. it can.

In this embodiment, the black light-shielding layer 8 is provided. However, depending on the state of uneven brightness near the light source when the liquid crystal device is used, for example, a gray light-shielding layer or the like has a higher light reflectance than black. A slightly higher light shielding layer may be provided.

In the present embodiment, the notch 102 is provided at the corner of the rectangular liquid crystal device sheet 1 so that, for example, when the notch 102 is located on the upper right, Can be determined to be in the correct position. Therefore, when the liquid crystal device sheet 1 is used for manufacturing the liquid crystal device, the sheet 101 can be easily arranged at an appropriate position.

(Structure of Liquid Crystal Device) Next, the structure of a liquid crystal device formed using the above-described liquid crystal device sheet will be described with reference to FIGS. FIG. 3 shows a liquid crystal device 200.
FIG. 3 is an exploded schematic perspective view of FIG. FIG. 4 is a partial cross-sectional view around the LED 12 as a light source of the liquid crystal device 200. FIG.
Is a side view showing the positional relationship between the LED 12 and the sheet 101. FIG. 6 is a plan view showing the positional relationship between the sheet 101 and the LEDs 12, and is a diagram when FIG. 5 is viewed from the sheet 101 side in the thickness direction of the sheet 101. FIG. In the liquid crystal device, the first sheet 1 of the liquid crystal device sheet 1 described above is used.
The release sheet 2 and the second release sheet 7 are peeled off and arranged in a state of the sheet 101 corresponding to the LEDs 12.

As shown in FIG. 3 and FIG.
Reference numeral 0 mainly includes a liquid crystal panel 10 and a side light type backlight 201 for irradiating the liquid crystal panel 10 with light.

The liquid crystal panel 10 includes a substrate 21 and a substrate 22
And a liquid crystal layer (not shown) sandwiched between these two substrates, and a pair of polarizing plates 23 arranged so as to sandwich the two substrates.

The backlight 201 is disposed adjacent to the substrate 22 of the liquid crystal panel 10 and has a light guide plate 11 having substantially the same size as the liquid crystal panel 10, and a light source disposed at an end of the light guide plate 11 as a light source. It mainly includes an LED (light emitting element) 12. Here, three LEDs 12 are used. The light guide plate 11 is used to guide and diffuse the light from the LED 12 to form a surface light source, and the light diffused by the light guide plate 11 is applied to the liquid crystal panel 10. Further, if necessary, an optical member such as a diffusion plate or a reflection plate may be further provided and used as the backlight 201. In this case, the diffusion plate is arranged on the light emitting surface side of the light guide plate, that is, on the surface on the liquid crystal panel side, and is used for diffusing light from the light source and uniformly irradiating the liquid crystal panel with the surface. Further, the reflection plate is disposed on the surface of the light guide plate facing the light emitting surface, and is used to reflect light from the light source to effectively use the light. In the present embodiment, the LED 12 is a frame 14 for housing the light guide plate 11.
Is fixedly arranged. The frame 14 includes a rectangular frame-shaped bottom portion and side walls formed along the sides of the bottom portion. The LED 12 is fixedly arranged on the frame portion at the bottom of the frame 14. The side wall of the frame 14 functions as a guide when the light guide plate 11 is inserted.
The positional relationship between 4 and light guide plate 11 is substantially fixed. Furthermore,
The liquid crystal panel 10 is also inserted into the frame 14, and the side wall of the frame 14 also functions as a guide for inserting the liquid crystal panel into the frame 14. In FIG. 3, the frame 14 and the polarizing plate 23 are omitted.

A circuit board 15 is fixed to the surface of the light guide plate 11 opposite to the surface on which the liquid crystal panel 10 is arranged. The connection terminal of the circuit board 15 and the connection terminal of the substrate 22 are connected to each other. Are electrically connected via a TCP (tape carrier package) 13 in which an IC chip is mounted on a flexible printed board on which a wiring pattern is formed.

The backlight 201 and the light guide plate 11 of the liquid crystal panel 10 are bonded and fixed by a double-sided adhesive tape 105 provided at the four corners of the outer peripheral portion interposed therebetween. In addition, the first surface corresponding to the LED 12 and having a black overall surface.
In a plan view, such that the surface 101a is located on the liquid crystal panel 10 side, and the second surface 101b having the white region 9 and the black region 16 having different light reflectivities is located on the backlight 201 side.
The sheet 101 is arranged so as to cover the ED 12.
As shown in FIGS. 4 and 5, the sheet 101 has a P
The light shielding layer 4 and the first adhesive layer 3 are formed on one surface of the ET film 5.
Are sequentially formed, and a light shielding layer 8 and a second adhesive layer 6 are formed on the other surface of the PET film 5. Although the second adhesive layer 6 is formed on both ends of the sheet 101, the second adhesive layer 6 may be formed on the entire surface of the PET film 5 so as to cover the light shielding layer 8. But,
When the second adhesive layer 6 is formed so as to cover the light-shielding layer 8, the light-shielding layer 8 is smeared and a preferable light reflectance cannot be obtained. It is desirable that the second adhesive layer 6 is formed so as not to overlap.

As described above, since the second surface 101b of the sheet 101 facing the LEDs 12 has a plurality of regions having different light reflectivities, the occurrence of uneven brightness of the backlight 201 near the LEDs 12 is prevented. A liquid crystal device having uniform brightness can be obtained. That is,
In the liquid crystal device of the present embodiment, when a sheet whose second surface facing the LEDs 12 is entirely white is used,
Brightness unevenness occurs in the area near the LED 12 of the backlight 201, and the uneven brightness tends to be bright in an area near the LED 12 and dark in an area near the middle of the two LEDs 12. For this reason, in this embodiment,
As shown in FIG. 5 and FIG.
The second surface of the sheet 101 is configured so that, when the 01 is incorporated, the region corresponding to the LED 12 becomes the black region 16 and the other region becomes the white region 9. Thereby, the light from the LED 12 is absorbed in the black region 16,
Since the light from the LED 12 is reflected in the white region 9,
As a result, the brightness of the area near the LED of the backlight 201 is made uniform, and the occurrence of uneven brightness is prevented. In the present embodiment, the white region 9 is a portion where the PET film 5 as the base material is exposed. However, the present invention is not limited to this, and a colored layer of another color may be formed. The area may be a region, and the degree of light reflectance may be adjusted according to the degree of luminance unevenness. In the present embodiment, the second
In the surface 101b, a color having a low light reflectance is formed in a region corresponding to the LED 12, but the present invention is not limited to this, and an area in which the light reflectance is reduced may be determined according to the distribution of uneven brightness.

Further, since the first surface 101a of the sheet 101 has a black color, the LEDs 12
0 can be blocked, and the sheet 101 can be blocked.
Has also a function as a light shielding sheet.

In this embodiment, the substantially rectangular sheet 101 has a notch 102 at one corner. By providing the cutout portions 102 in this manner, even when the pattern of the light shielding layer 8 of the sheet 101 is not symmetrical, it is possible to easily determine an appropriate position of the sheet 101 when incorporated in the liquid crystal device. Thereby, workability is improved in the step of attaching the sheet 101 during the manufacture of the liquid crystal device.

In the liquid crystal device according to the present embodiment,
Although the LEDs 12 are fixedly arranged on the frame 14, the sheet 101 can also be used for a liquid crystal device 200 having a structure in which the LEDs 12 are fixedly arranged on the substrate 114 as shown in FIG.

In the above embodiment, the sheet 101
As described above, a light-blocking layer is partially formed on one surface of a base material to form a plurality of regions having different light reflectivities, but the present invention is not limited to such a structure. If the substrate has a plurality of regions having different reflectances, the sheet 101
And the occurrence of uneven brightness can be prevented.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view of a liquid crystal device sheet according to an embodiment of the present invention.

FIG. 2 is a plan view of a liquid crystal device sheet according to an embodiment of the present invention.

FIG. 3 is an exploded schematic perspective view of the liquid crystal device according to the embodiment of the present invention.

FIG. 4 is a partial cross-sectional view showing the vicinity of an LED of the liquid crystal device shown in FIG.

FIG. 5 is a side view showing a positional relationship between an LED and a sheet.

FIG. 6 is a plan view showing a positional relationship between an LED and a sheet.

FIG. 7 is a partial cross-sectional view of another liquid crystal device according to an embodiment of the present invention.

DESCRIPTION OF SYMBOLS 1 ... Liquid crystal device sheet 2 ... First release sheet 3 ... First adhesive layer 4 ... Light shielding layer 5 ... PET film 6 ... Second adhesive layer 7 ... Second release sheet 8 ... light shielding layer 9 ... white area 10 ... liquid crystal panel 11 ... light guide plate 12 ... LED 16 ... black area 21 ... substrate 22 ... substrate 101 ... sheet 101a ... first surface of the sheet 101b ... second surface of the sheet 102 ...・ Notch 200: liquid crystal device

Claims (18)

[Claims] A liquid crystal panel sandwiching liquid crystal between a first substrate and a second substrate; a liquid crystal panel disposed adjacent to the liquid crystal panel on the first substrate side; and a light guide plate and an end face of the light guide plate. A backlight having a light source disposed along the same, and a sheet having at least a first surface and a second surface disposed corresponding to the light source between the backlight and the liquid crystal panel. A liquid crystal device comprising: the first surface is located on the liquid crystal panel side; the second surface is located on the backlight side; and the second surface is a plurality of regions having different light reflectivities. A liquid crystal device comprising: 2. The liquid crystal device according to claim 1, wherein a light shielding layer is formed on the first surface. 3. The plurality of regions having different light reflectivities include a first region corresponding to the light source and a second region having a higher light reflectivity than the first region. The liquid crystal device according to claim 1, wherein: 4. The liquid crystal device according to claim 3, wherein said second region is made of white. 5. The liquid crystal device according to claim 3, wherein the first region is made of black or gray. 6. The liquid crystal device according to claim 3, wherein a light shielding layer is formed in the first region. 7. The sheet according to claim 1, wherein the sheet has a substantially rectangular shape, and the sheet has a specifying unit for specifying an arbitrary corner of the rectangle. The liquid crystal device according to the above. 8. The liquid crystal device according to claim 7, wherein said specifying means is a notch formed at an arbitrary corner of said sheet. 9. A liquid crystal device sheet including a base material having a first surface and a second surface, wherein the second surface has a plurality of regions having different light reflectivities. For liquid crystal devices. 10. A base material having a first surface and a second surface, and a low reflection layer having a light reflectance lower than that of the base material partially formed on the second surface. A sheet for a liquid crystal device, comprising: 11. The liquid crystal device sheet according to claim 10, wherein the base material is made of white. 12. The liquid crystal device sheet according to claim 11, wherein the substrate is made of polyethylene terephthalate. 13. The sheet for a liquid crystal device according to claim 10, wherein the low reflection layer is a black layer. 14. The liquid crystal device sheet according to claim 10, further comprising a light shielding layer formed on the first surface of the base material. 15. A first adhesive layer formed on a surface of the light-shielding layer opposite to a surface in contact with the substrate, and a second adhesive layer formed on a second surface of the substrate. The liquid crystal device sheet according to claim 14, comprising: 16. A first release sheet formed on a surface of the first adhesive layer opposite to a surface in contact with the light shielding layer, and opposite to a surface of the second adhesive layer in contact with the base material. The liquid crystal device sheet according to claim 15, further comprising a second release sheet formed on the surface. 17. The liquid crystal device sheet according to claim 9, wherein the liquid crystal device sheet has a substantially rectangular shape, and the liquid crystal device sheet has a specification unit for specifying an arbitrary corner of the rectangle.
The liquid crystal device sheet according to any one of claims 1 to 16. 18. The liquid crystal device sheet according to claim 17, wherein said specifying means is a notch formed at an arbitrary corner of said sheet.