JP2004287120A - Ips (in-plane switching) liquid crystal module - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an IPS liquid crystal module in which leakage of backlight light from a gap between a liquid crystal cell and a bezel is prevented. <P>SOLUTION: The IPS liquid crystal module 10 includes the liquid crystal cell 12, an optical sheet 16 disposed on the lower side of the liquid crystal cell 12 to evenly guide light 26 to the liquid crystal cell 12, a light guide plate 18 to guide the light 26 to the optical sheet 16, a frame 20 having a groove 30 for attaching and positioning the optical sheet 16 arranged thereon and covering peripheral parts of the liquid crystal cell 12, the optical sheet 16 and the light guide plate 18 and a bezel 22 covering peripheral parts of the liquid crystal cell 12 and the frame 20 and having a light absorbing body 24 arranged inside. Because the light absorbing body 24 absorbs the light 26 leaking out from the groove 30, deterioration of display quality of the liquid crystal module 10 caused by leakage of the light 26 from the gap d between the liquid crystal cell and the bezel 22 does not take place. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an IPS (in-plane-switching) liquid crystal module that prevents light leakage from a backlight.
[0002]
[Prior art]
A liquid crystal module is configured by attaching a bezel, a frame, a light guide plate, an optical sheet, and the like to the liquid crystal cell. As shown in FIGS. 4A, 4B, and 4C, an optical sheet 16 is provided below the liquid crystal cell 12, and a light guide plate 18 is provided below the optical sheet 16. The light 26 propagating through the light guide plate 18 is uniformly supplied to the liquid crystal cell 12 by the optical sheet 16. The optical sheet 16 includes a diffusion sheet 14 and a prism sheet 15. A backlight is formed by fixing a light source (not shown) such as a fluorescent lamp, a light guide plate 18 and an optical sheet 16 to the frame 20. The frame 20 is provided with a groove 30 for mounting and positioning the optical sheet 16. An ear (projection) 28 is formed by projecting a part of the optical sheet 16, and the ear 28 is fitted into the groove 30. A bezel 22 is provided on the periphery of the frame 20 and the liquid crystal cell 12. The bezel 22 collects the components of the liquid crystal module 10 into one, or attaches the liquid crystal module 10 to a product housing.
[0003]
In the case of the IPS liquid crystal module 10, when the bezel 22 is in close contact with the liquid crystal cell 12 and the bezel 22 presses the liquid crystal cell 12, the glass substrate of the liquid crystal cell 12 is distorted. The distortion of the glass substrate changes the thickness of the liquid crystal layer. Therefore, the portion of the liquid crystal cell 12 which is in contact with the bezel 22 is whitened and the display quality is degraded. It is necessary to provide a gap d between the liquid crystal cell 12 and the bezel 22. In a TN (twisted nematic) liquid crystal module, the display quality of the liquid crystal module 10 does not deteriorate even if the bezel 22 and the liquid crystal cell 12 are brought into close contact with each other. This is because the alignment of the liquid crystal in the liquid crystal layer of the TN liquid crystal module is different from that of the IPS liquid crystal module, and therefore, even if the thickness of the liquid crystal layer changes, the alignment of the liquid crystal is little affected.
[0004]
As described above, the groove 30 is cut in the frame 20 to fix the optical sheet 16 to the frame 20. The light 26 is guided from the light guide plate 18 to the liquid crystal cell 12 via the optical sheet 16, but a part of the light 26 leaks from the groove 30. Since the material of the bezel 22 is stainless steel, pure aluminum, a duralumin-based alloy, or the like, the leaked light 26 is reflected by the bezel 22 and appears in the display area of the liquid crystal cell 12 from the gap d between the liquid crystal cells 12. This causes light leakage and lowers the display quality.
[0005]
As shown in FIG. 5, when the wall 32 is provided in the groove 30 of the frame 20, the light 32 does not reach the bezel 22 due to the wall 32. However, since the material of the frame 20 is a high-reflection type material, the light 26 is reflected on the wall 32 and leaks from the gap d between the liquid crystal cell 12 and the bezel 22.
[0006]
A method of filling the gap d with an elastic material is conceivable. However, since the gap d is 0.1 to 0.2 mm, it is very difficult to fill the gap d with an elastic material without applying pressure to the liquid crystal cell 12.
[0007]
[Problems to be solved by the invention]
An object of the present invention is to provide an IPS liquid crystal module in which light of a backlight is prevented from leaking from a gap between a liquid crystal cell and a bezel.
[0008]
[Means for Solving the Problems]
The gist of the IPS liquid crystal module according to the present invention is to provide a liquid crystal cell, an optical sheet provided below the liquid crystal cell and having a protruding portion, for guiding light to the liquid crystal cell, and for guiding light to the optical sheet. A light guide plate, a groove in which the protrusion of the optical sheet is fitted, and a frame covering the liquid crystal cell, the optical sheet and the peripheral edge of the light guide plate, and a bezel covering the liquid crystal cell and the peripheral edge of the frame. In the IPS liquid crystal module, a light absorber is provided on a peripheral edge of the protruding portion, a side wall of a groove of a frame, or an inner wall of a bezel. The light absorber absorbs light and prevents light from leaking from the gap between the liquid crystal cell and the bezel.
[0009]
The light absorber is constituted by black tape, black printing, black painting, or chrome plating.
[0010]
BEST MODE FOR CARRYING OUT THE INVENTION
Next, an embodiment of the IPS liquid crystal module according to the present invention will be described with reference to the drawings. The top view of the liquid crystal module of the present invention is a top view of a conventional liquid crystal module. The sectional view taken along the line BB of the liquid crystal module of the present invention is the same as FIG. 4 (c). FIG. 1 is a sectional view of the liquid crystal module taken along the line AA in the present invention.
[0011]
The IPS liquid crystal module 10 of the present invention includes a liquid crystal cell 12, an optical sheet 16 provided below the liquid crystal cell 12, for guiding the light 26 evenly to the liquid crystal cell 12, and for guiding the light 26 to the optical sheet 16. A light guide plate 18, a groove 30 for mounting and positioning the optical sheet 16 are provided, and a frame 20 covering the liquid crystal cell 12, the optical sheet 16 and the periphery of the light guide plate 18, and the liquid crystal cell 12 and the periphery of the frame 20 are formed. And a bezel 22 provided with a light absorber 24a on the inner wall. When the liquid crystal cell 12 and the bezel 22 come into close contact with each other, the liquid crystal cell 12 at the place where the liquid crystal cell 12 comes into contact with the bezel 22 becomes white.
[0012]
The optical sheet 16 includes a diffusion sheet 14 and a prism sheet 15. A backlight is configured by attaching a light source (not shown) such as a fluorescent lamp, a light guide plate 18 and an optical sheet 16 to the frame 20. The optical sheet 16 is provided with a protruding ear 28, and the ear 28 is fitted into the groove 30, so that the optical sheet 16 can be fixed to the frame 20.
[0013]
The light absorber 24a is configured by black tape, black printing, black painting, or chrome plating. The black tape or the like does not adhere to the liquid crystal cell 12. The color of the chrome plating is a dark gray almost black, and can absorb the light 26.
[0014]
When the light 26 is guided from the light guide plate 18 to the liquid crystal cell 12 via the optical sheet 16, the light 26 leaks from the groove 30 of the frame 20. The leaked light 26 is absorbed by the light absorber 24a on the inner wall of the bezel 22, and does not leak from the gap d between the bezel 22 and the liquid crystal cell 12. Therefore, the display quality of the IPS liquid crystal module 10 does not deteriorate.
[0015]
In FIG. 1, the light absorber 24 a is provided on the entire inner wall of the bezel 22. However, the light absorber 24 a may be provided only on a portion where the light 28 leaking from the groove 30 hits.
[0016]
As shown in FIG. 2, a case will be described in which a wall 32 is provided in the groove 30 of the frame 20 and the light 26 does not leak to the bezel 22. Also in this case, the light 26 is reflected by the wall 32 of the frame 20 and leaks between the liquid crystal cell 12 and the bezel 22. By providing the same light absorber 24b as in FIG. 1 on the wall 32, in other words, the inner wall of the groove 30, the light 26 is prevented from leaking. Further, the wall 32 may be constituted by the light absorber 24b.
[0017]
Although the light absorber 24 is provided on the inner wall of the bezel 22 in FIG. 1, the light absorber 24c may be provided so as to cover the periphery of the ear 28 of the optical sheet 16 as shown in FIG. The light 26 is prevented from leaking from the optical sheet 16 by covering the periphery of the ear 28 with the light absorber 24c.
[0018]
The embodiments of the present invention have been described above, but the present invention is not limited to the above embodiments. In addition, the present invention can be implemented in various modified, modified, and changed forms based on the knowledge of those skilled in the art without departing from the scope of the present invention.
[0019]
【The invention's effect】
According to the present invention, light leakage from the gap between the liquid crystal cell and the bezel can be eliminated by the light absorber. Since the liquid crystal cell and the bezel are not brought into close contact with each other, the display quality of the IPS liquid crystal module is not reduced without causing the liquid crystal cell to become white.
[Brief description of the drawings]
FIG. 1 is a sectional view of an IPS liquid crystal module according to the present invention, in which a light absorber is provided on a bezel.
FIG. 2 is a cross-sectional view of the IPS liquid crystal module according to the present invention, in which a light absorber is provided on a frame wall.
FIG. 3 is a cross-sectional view of an IPS liquid crystal module according to the present invention, in which a light absorber is provided at an ear of an optical sheet.
4A and 4B are diagrams of a conventional IPS liquid crystal module, in which FIG. 4A is a cross-sectional view, FIG. 4B is a cross-sectional view along AA, and FIG. 4C is a cross-sectional view along BB.
FIG. 5 is a cross-sectional view when a frame is provided with a wall in FIG. 4 (b).
[Explanation of symbols]
10: IPS liquid crystal module 12: liquid crystal cell 14: diffusion sheet 15: prism sheet 16: optical sheet 18: light guide plate 20: frame 22: bezels 24a, 24b, 24c: light absorber 26: light 28: ear 30: groove 32 :wall

Claims (2)

A liquid crystal cell,
An optical sheet provided at a lower portion of the liquid crystal cell, having a protrusion, and guiding light to the liquid crystal cell,
A light guide plate for guiding light to the optical sheet,
A groove is provided in which the protrusion of the optical sheet is fitted, and a frame that covers the periphery of the liquid crystal cell, the optical sheet and the light guide plate,
A bezel covering the periphery of the liquid crystal cell and the frame,
An IPS liquid crystal module comprising:
An IPS module having a light absorber provided on a peripheral edge of the protrusion, a side wall of a groove of a frame, or an inner wall of a bezel. The liquid crystal module according to claim 1, wherein the light absorber is formed by black tape, black printing, black painting, or chrome plating.

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