JP2004029319A - Flat panel display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a liquid crystal display device in which light is prevented from leaking from an end part of a liquid crystal cell. <P>SOLUTION: A light guide plate 21 is disposed on the rear surface side of the liquid crystal cell 11. The front side of the liquid crystal cell 11 is exposed and the liquid crystal cell 11 is contained in a frame 1. The range extending from the peripheral part of the rear surface side of the liquid crystal cell 11 to the end part of the liquid crystal cell 11 is covered with a light shielding tape 16. The light shielding tape 16 shields light L passing through the end part of the liquid crystal cell 11. The light L passing through the end part of the liquid crystal cell 11, reflected by the frame 1 and emitted to the front surface side of the liquid crystal cell 11 is prevented and the light L is prevented from leaking from the end part of the liquid crystal cell 11. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a flat display device that displays an image on a flat display cell based on light from a surface light source unit.
[0002]
[Prior art]
Conventionally, a liquid crystal display device as a flat display device of this type has a frame made of resin in a square frame shape in plan view, and a rectangular opening is formed in the center of the frame. I have. The frame is provided with the same bezel as in a plan view in a square shape so as to cover the outside of the frame. The bezel has an L-shaped cross section on each side, and a substantially rectangular display window is opened at the center.
[0003]
Further, in the bezel, a substantially rectangular flat liquid crystal cell as a flat display cell is exposed from the display window of the bezel and housed inside. The liquid crystal cell has, for example, translucency, and a backlight as a rectangular flat plate-shaped surface light source unit for irradiating the liquid crystal cell with planar light is attached to the back side of the liquid crystal cell. ing. The backlight is accommodated in the bezel in which the liquid crystal cell is accommodated so as to be superimposed on the back side of the liquid crystal cell.
[0004]
Further, a liquid crystal injection port for injecting liquid crystal into the inside of the liquid crystal cell is provided at an end of the liquid crystal cell in a plane direction in a protruding state. An optical sheet, for example, as a rectangular sheet is disposed between the liquid crystal cell and the backlight, and the optical sheet diffuses a planar light distribution from the backlight. Alternatively, the light is condensed and substantially uniformly incident on the back surface side of the liquid crystal cell.
[0005]
[Problems to be solved by the invention]
In the above-described liquid crystal display device, since the liquid crystal injection port formed in the liquid crystal cell protrudes from the end face of the liquid crystal cell, it is necessary to cut the inner surface of the frame facing the liquid crystal injection port. When the inner surface of the frame is shaved, the width between the liquid crystal cell and the frame increases in the vicinity thereof, so that light leaking from the backlight toward the end leaks, and the leaked light is transmitted to the frame. The light is reflected by the liquid crystal cell and is reflected by the gap between the bezel and the liquid crystal cell or through the liquid crystal cell.
[0006]
Further, in recent years, the liquid crystal display device has been made thinner to achieve miniaturization and weight reduction, so that the periphery of the display window of the bezel does not extend to the periphery of the polarizing plate attached to the surface of the liquid crystal cell, that is, the polarizing plate has a structure. If the structure is completely exposed from the opening of the bezel, light leakage from the edge of the liquid crystal cell is reflected by the frame or bezel, resulting in light leakage from the liquid crystal cell. There is a problem that it becomes very large.
[0007]
The present invention has been made in view of such a point, and an object of the present invention is to provide a flat display device capable of suppressing light leakage from a flat display cell.
[0008]
[Means for Solving the Problems]
The present invention relates to a flat display cell having a light-transmitting property, a frame for exposing the front surface side of the flat display cell to be accommodated, and a frame disposed on the rear surface side of the flat display cell and accommodated in the frame, A surface light source unit for irradiating light to the display cell, and a light shield for covering from the edge on the back surface side of the flat display cell to the end of the flat display cell and blocking light transmitted through the end of the flat display cell. And a body.
[0009]
Then, the front side of the flat display cell in which the surface light source unit is disposed on the back side is exposed and housed in the frame. The light from the edge on the back surface side of the flat display cell to the end of the flat display cell is covered with a light shield, and light transmitted through the end of the flat display cell is shielded by the light shield. Light transmitted through the edge of the flat display cell, reflected by the frame, and emitted to the surface side of the flat display cell can be suppressed. Light leakage from the flat display cell can be suppressed.
[0010]
A flat display cell having a light-transmitting property, a frame for exposing the front surface side of the flat display cell to be accommodated therein, and a flat display cell disposed on the back side of the flat display cell and accommodated in the frame; A surface light source unit for irradiating light to the surface light source unit, the surface light source unit, disposed on at least a main surface of the frame in a path formed between the flat display cell and the frame, and an end of the flat display cell. And a light-shielding body that shields transmitted light.
[0011]
A light shield is disposed on at least the main surface of the frame in a path formed between the surface light source unit, the flat display cell, and the frame, and the light that is transmitted through the edge of the flat display cell is transmitted by the light shield. Shade. Light transmitted through the edge of the flat display cell, reflected by the frame, and emitted to the surface side of the flat display cell can be suppressed. Light leakage from the flat display cell can be suppressed.
[0012]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, a first embodiment of a liquid crystal display device as a flat display device of the present invention will be described with reference to FIG.
[0013]
In FIG. 1, reference numeral 1 denotes a resin frame, and the frame 1 is formed in a substantially rectangular frame shape. A rectangular opening 2 is formed in the center of the frame 1, and the cross section of each side is formed in a rectangular shape. Further, on the back surface of the frame 1, there is provided a groove 3 having an arc-shaped cross section along the circumferential direction of the frame 1.
[0014]
A holding piece 6 protruding along the surface direction of the frame 1 is provided on the inner peripheral edge on the back surface side of the frame 1 along the inner peripheral edge of the frame 1. Further, on the inner peripheral edge on the front surface side of the frame 1, a step-shaped mounting step 7 is provided along the inner peripheral edge of the frame 1 along the surface direction of the frame 1.
[0015]
Further, a substantially rectangular frame-shaped metal bezel 8 substantially similar to the frame 1 is attached to the frame 1 so as to cover a front side, that is, a front side outside the frame 1. The cross section of each side of the bezel 8 is formed in an L-shape, and a display window 9 as a rectangular display opening is opened at the center of the bezel 8. Further, inside the bezel 8, the liquid crystal cell 11 is accommodated by exposing a display area of a substantially rectangular flat liquid crystal cell 11 as a flat display cell from a display window 9 of the bezel 8. Further, as shown in FIG. 1, the liquid crystal cell 11 has translucency, and the peripheral edge portion is held by the mounting step 7 of the frame 1 and is accommodated in the frame 1. 8 and the mounting step portion 7 of the frame 1 are sandwiched and held.
[0016]
Here, the liquid crystal cell 11 includes a rectangular plate-shaped array substrate 12 in which display pixel electrodes (not shown) are formed in a matrix, and a rectangular plate-shaped opposing substrate 13 is attached to the array substrate 12. Have been. The counter substrate 13 is formed to have a size substantially equal to the size of the array substrate 12. Further, a liquid crystal (not shown) is interposed between the array substrate 12 and the counter substrate 13. On the outer surfaces of the array substrate 12 and the opposing substrate 13, rectangular flat-plate-like polarizing plates 14 each having a shorter side than the array substrate 12 and the opposing substrate 13 are attached. Each of the polarizing plates 14 is attached so as to cover the center of each surface of the array substrate 12 and the counter substrate 13.
[0017]
Further, as shown in FIG. 1, a black matrix 15 that blocks incident light is disposed between the array substrate 12 and the opposing substrate 13 at the periphery of the liquid crystal cell 11 as a flat display cell. Further, a tape-shaped light-shielding tape 16 as a light-shielding member that shields at least a part of the incident light L is attached to a peripheral portion on the back surface side of the liquid crystal cell 11.
[0018]
The light-shielding tape 16 is bent so as to have an L-shaped cross section, and one side is attached to the periphery of the surface of the counter substrate 13 located at the periphery of the polarizing plate 14. The other side of the light-shielding tape 16 is bent at a right angle toward the surface of the liquid crystal cell 11 so as to cover the respective end surfaces of the counter substrate 13 and the array substrate 12 of the liquid crystal cell 11. It is attached to each end of the array substrate 12 and the counter substrate 13 by being attached.
[0019]
Further, an acrylic light guide plate 21 constituting a rectangular flat plate surface light source unit is attached to the back surface of the liquid crystal cell 11 accommodated in the bezel 8, which is the side facing the display window 9 of the bezel 8. ing. The periphery of the light guide plate 21 is supported by the mounting step 7 of the bezel 8, and the light guide plate 21 is accommodated in the bezel 8 in which the liquid crystal cell 11 is accommodated such that the front surface side is overlapped with the back surface side of the liquid crystal cell 11. Have been.
[0020]
The light guide plate 21 irradiates planar light to the back surface of the liquid crystal cell 11 so that an image displayed on the liquid crystal cell 11 can be viewed. Further, a reflection sheet 22 is attached to each of the back surface side and the peripheral edge of the light guide plate 21. The reflection sheet 22 reflects light emitted from the rear surface and both ends of the light guide plate 21 and makes the light incident on the rear surface side of the liquid crystal cell 11 substantially uniformly again.
[0021]
Further, an optical sheet 23 as a substantially rectangular sheet-shaped sheet is interposed between the back side of the liquid crystal cell 11 and the front side of the light guide plate 21. The optical sheet 23 diffuses or condenses the planar light distribution from the light guide plate 21 and makes the light substantially uniformly enter the rear surface of the liquid crystal cell 11. As shown in FIG. 1, the optical sheet 23 is configured such that, for example, two prism sheets 25 are overlapped on the surface side of one diffusion sheet 24. Each of the diffusion sheet 24 and each of the prism sheets 25 is formed in the same shape as each other, and has a smaller width dimension than the surface of the reflection sheet 22.
[0022]
Here, a backlight 20 is configured by a light source (not shown) that causes light to enter the light guide plate 21, the light guide plate 21, the reflection sheet 22, and the optical sheet 23.
[0023]
Next, the operation of the first embodiment will be described.
[0024]
First, the light source is turned on, and when light from this light source is incident on the light guide plate 21, the light is guided inside the light guide plate 21, and is reflected by the reflection sheet 22, and the like. And is radiated to the liquid crystal cell 11 via the optical sheet 23.
[0025]
At this time, the light transmitted through the optical sheet 23 is diffused or condensed by each of the diffusion sheet 24 and each prism sheet 25 of the optical sheet 23 and is incident on the rear surface of the liquid crystal cell 11 substantially uniformly.
[0026]
Then, an image displayed on the display area of the liquid crystal cell 11 can be viewed from the front side of the liquid crystal cell 11 by the light incident on the back side of the liquid crystal cell 11.
[0027]
As described above, according to the first embodiment, one side of the light shielding tape 16 that shields the light L that is undesirably incident on the liquid crystal cell 11 is separated from the polarizing plate 14 on the back side of the liquid crystal cell 11. Is also adhered to the periphery of the opposing substrate 13 located on the periphery, and the other side of the light-shielding tape 16 bent is adhered to the end surfaces of the array substrate 12 and the opposing substrate 13 of the liquid crystal cell 11, respectively. 13 and the end faces of the array substrate 12 are covered.
[0028]
As a result, the light L shown in FIG. 1 radiated to the end of the liquid crystal cell 11 can be shielded by the other side of the light shielding tape 16. Therefore, the light that passes through the end of the liquid crystal cell 11 and is reflected on the inner side surface of the mounting step 7 of the frame 1, passes through the gap of the black matrix 15, and is emitted to the surface of the liquid crystal cell 11. L, that is, transmission of light L from between the display window 9 of the bezel 8 and the polarizing plate 14 located on the surface side of the liquid crystal cell 11 can be suppressed.
[0029]
Therefore, light leakage on the surface of the liquid crystal cell 11 can be sufficiently prevented. Further, since uneven brightness on the surface of the liquid crystal cell 11 can be prevented, the image displayed on the liquid crystal cell 11 can be more easily viewed. Therefore, the usability of the user can be improved and the occurrence of light leakage failure can be reduced.
[0030]
Next, a second embodiment of the present invention will be described with reference to FIGS.
[0031]
The liquid crystal display device shown in FIGS. 2 and 3 is basically the same as the liquid crystal display device shown in FIG. 1, except that a light-shielding member 31 as a light-shielding member that shields at least a part of the incident light L is framed. The light L is attached to the inner surface of the optical sheet 1 to block the light L transmitted through the end of the optical sheet 23 in the plane direction.
[0032]
A concave groove 3 is formed on the outer surface of the frame 1, and a step-shaped holding step 32 is formed on the inner edge of the back side of the frame 1. The holding step 32 is provided along the longitudinal direction of one side surface of the frame 1.
[0033]
In addition, the backlight 20 includes a straight tubular discharge lamp 35 as a lamp body as an elongated cylindrical linear light source body which is a linear light source for irradiating linear light. The outer edge of the front side of the discharge lamp 35 is held by the holding step 32 of the frame 1. One end of the light guide plate 21 as a substantially rectangular flat surface light source converter is turned to one side of the discharge lamp 35, and the light guide plate 21 is attached to the discharge lamp 35 in a state where the one end is brought close to the light guide plate 21.
[0034]
The light guide plate 21 is made of acrylic having a quadrangular shape in plan view, and is disposed in a state where the plane direction is parallel to the axial direction of the discharge lamp 35. Further, the light guide plate 21 is provided so as to be located on the side opposite to the display window 9 of the bezel 8 which is the back side of the liquid crystal cell 11. That is, the light guide plate 21 converts the linear light from the discharge lamp 35 into a planar light source that is planar light. In addition, on the back side of the light guide plate 21, a reflection sheet 22 that reflects light on the back side of the light guide plate 21 is provided.
[0035]
Further, a flat plate-shaped lamp reflector 36 is attached to a portion of the front surface of the light guide plate 21 facing the display window 9 of the bezel 8, that is, the entire front edge and the rear side of the light guide plate 21, respectively. ing. The lamp reflector 36 covers the outer peripheral portion of the discharge lamp 35 along the circumferential direction while including the discharge lamp 35. The lamp reflector 36 reflects the light from the discharge lamp 35 and makes the light incident on the light guide plate 21, and reflects the light transmitted through the light guide plate 21 and makes the light enter the rear surface side of the liquid crystal cell 11. Further, an optical sheet 23 is disposed between the rear surface of the liquid crystal cell 11 and the front surface of the light guide plate 21.
[0036]
On the other hand, a light-blocking sheet 38 as a light-blocking member that blocks at least a part of the incident light L is attached to a peripheral portion on the back surface side of the liquid crystal cell 11. The light-shielding sheet 38 is disposed between the peripheral edge of the surface of the counter substrate 13 located on the peripheral edge of the polarizing plate 14 and the prism sheet 25 located on the surface of the optical sheet 23.
[0037]
Further, the light-shielding member 31 is formed in the shape of an elongated prism having a rectangular cross section, and is made of, for example, black rubber having a light absorbing property. As shown in FIG. 2, the light shielding member 31 is provided in a space formed by each of the end of the optical sheet 23, the end of the liquid crystal cell 11, the inner surface of the frame 1, and the inner surface of the bezel 8. The light path 41 is disposed in the existing light path 41, and is selected to have a sufficient thickness so as to suppress the reflected light on the main surface of the frame 1 and to reduce the light path 41 itself. Specifically, the light blocking member 31 is held by the holding step 32 of the frame 1 and attached along the inner side surface of the frame 1. That is, the light shielding member 31 is attached at a position where the light L that is transmitted through the end of the optical sheet 23 or the end of the liquid crystal cell 11 and enters the optical path 41 is irradiated. Partly shade.
[0038]
Therefore, the liquid crystal display device shown in FIGS. 2 and 3 converts the linear light from the discharge lamp 35 of the backlight 20 into a planar shape by the light guide plate 21 and converts the planar light into the optical sheet 23. The light L that is generated when the light is incident on the back surface side of the liquid crystal cell 11 through the end of the optical sheet 23 or the end of the liquid crystal cell 11 and enters the optical path 41 in the frame 1 is generated. A light-shielding member 31 is attached to the inner surface of the frame 1 on which light is incident, and the light L incident on the light path 41 is incident on the light-shielding member 31 to shield the light, so that the same operation as the liquid crystal display device shown in FIG. The effect can be achieved.
[0039]
In the second embodiment, the light shielding member 31 is attached to the inner surface of the frame 1. However, if the light L can be shielded from the optical sheet 23 or the end of the liquid crystal cell 11, the light shielding member 31 may be used. Regardless of the position in the optical path 41 where light L may leak from the optical sheet 23 or the end of the liquid crystal cell 11, for example, the light shielding member 31 is attached to the end of the optical sheet 23, The same operation and effect as the embodiment can be obtained.
[0040]
In the above embodiments, the light L from the optical sheet 23 or the end of the liquid crystal cell 11 is shielded by the light shielding tape 16 or the light shielding member 31 and the light shielding sheet 38. The light-shielding member 31 and the light-shielding sheet 38 are used as a low-reflection member that sufficiently absorbs the light L from the end of the optical sheet 23 or the liquid crystal cell 11 or absorbs the light L from the end of the optical sheet 23 or the liquid crystal cell 11. The light absorbing member may have any configuration as long as it can shield at least a part of the light L from the end of the optical sheet 23 or the liquid crystal cell 11.
[0041]
Further, the liquid crystal display device for displaying an image in the liquid crystal cell 11 has been described. However, a flat display device having a light-transmitting flat display cell other than the liquid crystal cell 11 can also be used.
[0042]
【The invention's effect】
According to the present invention, the light from the edge on the rear surface side of the flat display cell to the end of the flat display cell is covered with a light shield, and light transmitted through the end of the flat display cell is shielded by the light shield. Since light that is transmitted through the edge of the flat display cell, reflected by the frame, and emitted to the surface of the flat display cell can be suppressed, light leakage from the flat display cell can be suppressed.
[0043]
In addition, a light shield is disposed on at least the main surface of the frame in a path formed between the surface light source unit, the flat display cell, and the frame, and the light shield transmits light transmitted through the end of the flat display cell. If light is shielded, light that passes through the end of the flat display cell, is reflected by the frame, and is emitted to the front side of the flat display cell can be suppressed, so that light leakage from the flat display cell is suppressed. it can.
[Brief description of the drawings]
FIG. 1 is an explanatory cross-sectional view showing a part of a first embodiment of a flat panel display according to the present invention.
FIG. 2 is an explanatory sectional view showing a part of a flat panel display according to a second embodiment of the present invention.
FIG. 3 is a front view showing a part of the flat panel display device.
[Explanation of symbols]
1 frame 11 liquid crystal cell 16 as a flat display cell 16 light-shielding tape 21 as a light-shielding member light-guide plate 31 as a surface light source section light-shielding member 41 as a light-shielding member Light path L as a path Light

Claims (2)

A flat display cell having translucency;
A frame that exposes and accommodates the front side of the flat display cell,
A surface light source unit disposed on the back side of the flat display cell and housed in the frame, and irradiating light to the flat display cell,
A flat panel display device comprising: a light-shielding body that covers an edge of the flat display cell from the rear surface side edge to an end of the flat display cell, and shields light transmitted through the edge of the flat display cell. . A flat display cell having translucency;
A frame that exposes and accommodates the front side of the flat display cell,
A surface light source unit disposed on the back side of the flat display cell and housed in the frame, and irradiating light to the flat display cell,
A light-shielding member disposed on at least a main surface of the frame in a path formed between the surface light source portion, the flat display cell and the frame, and configured to block light transmitted through an end of the flat display cell. A flat panel display characterized by the following.

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