KR100852107B1 - Reflection type LCD - Google Patents

Abstract

A reflective liquid crystal display device of the present invention comprises: a front plate having a non-display area at a periphery and a display area at a central portion thereof; A first electrode layer having a plurality of first electrodes formed on the bottom surface of the front plate in parallel with each other in a predetermined pattern; An edge bonded to the front plate to be spaced apart from the front plate, the substrate having a non-display area at a peripheral portion corresponding to the front plate and a display area at a central portion thereof; A second electrode layer having a plurality of second electrodes formed on the upper surface of the substrate in parallel with each other in a predetermined pattern; A reflective film disposed between each of the second electrodes and the display area of the substrate and having a width smaller than that of the second electrode so as to be embedded in the second electrode; First and second alignment layers coated on the bottom of the first electrode layer and on the second electrode layer, respectively; And a liquid crystal layer injected between the first and second alignment layers.

Description

Reflective Liquid Crystal Display {Reflection type LCD}

1 and 2 are a plan view and a cross-sectional view schematically showing a state in which a reflective film and an electrode are formed on a substrate in a conventional reflective liquid crystal display device.

3 is a cross-sectional view of a reflective liquid crystal display device according to the present invention;

4 is a plan view schematically illustrating a reflection film and an electrode formed on a substrate in the reflective liquid crystal display according to the present invention;

FIG. 5 is a schematic cross-sectional view of an electrode formed in a non-display area on a substrate in FIG. 4; FIG.

<Brief description of symbols for the main parts of the drawings>

100 ... reflective LCD 110 ... front panel

120 ... substrate 130 ... color filter layer

140 ... transparent layer 150 ... first electrode layer

160 ... second electrode layer 170 ... reflective film

181,182 Orientation layer 190 ... Liquid crystal layer

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to reflective liquid crystal displays, and more particularly to improved reflective liquid crystal displays that enable inspection of short circuits without damaging the electrodes arranged on the substrate.

Conventional reflection type liquid crystal display devices mainly use a twisted nematic (TN) liquid crystal or a super twisted anti-static (STN) liquid crystal to implement a monochromatic image. Much research has been made on reflective liquid crystal display devices that implement the method.

Patent Publication No. 2001-022609 shows an example of a reflective liquid crystal display device implementing such a color image, which has a structure that reflects external light or transmits light emitted from a backlight using a reflective polarizer. The display device has a problem in that contrast is improved by using a reflective polarizer but brightness is relatively lowered.

In order to solve this problem, Patent Application No. 2001-079713 discloses a reflective liquid crystal display device filed by the present applicant, Figures 1 and 2 is a state in which the reflective film and the electrode is formed on the substrate in the display device A plan view and a cross-sectional view schematically.

Referring to the drawings, a non-display area D1 is provided at a peripheral portion with a non-display area D1 at a peripheral portion of the substrate 10 positioned apart from the front plate (not shown) on which image light is projected, and the display area D2 at the other center part thereof. ) Is provided. The non-display area refers to an area in which a liquid crystal display device is interposed in a case (not shown) so that image light cannot be projected through the front panel.                         

The upper surface of the substrate 10 facing the front plate includes a plurality of transparent indium tin oxide (ITO) electrodes 20 extending in a stripe pattern in parallel with each other. Between the substrate 10 and each of the ITO electrodes 20a to 20d, a metal reflective film 30a to 30d is interposed therebetween, and the width thereof is narrower than the width of the ITO electrode so as to be embedded therein. In addition, the ITO electrode 20 and the reflective film 30 extend to the non-display area D1.

In the manufacturing process of the liquid crystal display, after forming the ITO electrode 20 and the reflective film 30 on the substrate 10, it is required to inspect whether each of the ITO electrodes 20a to 20d does not cause a short to each other. do. The short test is usually performed by contacting a short check probe to an ITO electrode in the non-display area D1. The short end of the short check probe is sharp, so that the ITO electrode 20 is relatively weak in strength. And damage to the reflective film 30 therein.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a reflective liquid crystal display device capable of inspecting whether the electrode pattern is short or not without damaging the ITO electrode formed on the substrate.

In order to achieve the above object, the reflective liquid crystal display of the present invention comprises: a front plate provided with a non-display area and a display area in the other center portion;

A first electrode layer having a plurality of first electrodes formed on the bottom surface of the front plate in parallel with each other in a predetermined pattern;

An edge bonded to the front plate to be spaced apart from the front plate, the substrate having a non-display area at a peripheral portion corresponding to the front plate and a display area at a central portion thereof;

A second electrode layer having a plurality of second electrodes formed on the upper surface of the substrate in parallel with each other in a predetermined pattern;

A reflective film disposed between each of the second electrodes and the display area of the substrate and having a width smaller than that of the second electrode so as to be embedded in the second electrode;

First and second alignment layers coated on the bottom of the first electrode layer and on the second electrode layer, respectively; And

And a liquid crystal layer injected between the first and second alignment layers.

A reflective liquid crystal display according to an exemplary embodiment of the present invention includes a color filter layer including a plurality of red, green, and blue unit filters formed in parallel with each other in a predetermined pattern between the front plate and the first electrode layer. It is characterized by further comprising.

The reflective liquid crystal display may further include a transparent layer positioned between each unit filter and the front plate and having a width smaller than that of the unit filter so as to be embedded in the unit filter.

The first electrode of the reflective liquid crystal display according to the present invention is perpendicular to the unit filters, and the second electrodes are arranged in parallel so as to correspond one-to-one with the unit filters.

The second electrode of the reflective color liquid crystal display according to the present invention is characterized in that the transparent ITO electrode, the reflective film is a metal film.

In addition, the reflective film is characterized in that the material of one of the group consisting of silver, silver alloy, aluminum, and aluminum alloy.

Hereinafter, a reflective liquid crystal display according to the present invention will be described in detail with reference to the accompanying drawings.

3 is a cross-sectional view of a reflective liquid crystal display device according to the present invention.

Referring to the drawings, the reflective liquid crystal display 100 includes a transparent front panel 110 and red, green, and blue unit filters 130R, 130G, and 130B formed in a stripe pattern parallel to each other on the bottom surface of the front panel. ) And a transparent filter layer 140a to 140c interposed between the unit filter and the front plate 110. The transparent layer has a width smaller than that of each of the unit filters 130R, 130G, and 130B, and is embedded in the unit filter. As a result, the unit filter reflects a thick transmission region T1 and a relatively thin thickness. It divides into the area | region T2. The transparent layers 140a to 140c may be formed of a transparent organic film having a thickness of about 0.1 μm to about 0.2 μm.

Reflective liquid crystal display 100 also includes a first electrode layer 150 of a plurality of first electrodes formed parallel to each other and preferably in a stripe pattern below the color filter layer 130. A second electrode layer comprising a plurality of second electrodes 160a to 160c formed in parallel with each other and preferably in a stripe pattern on an upper surface of the transparent substrate 120 positioned to be spaced apart from the front plate 110 by a predetermined distance. And 160. Preferably, the plurality of first electrodes and the second electrodes are transparent electrodes made of ITO, and are arranged to be orthogonal to each other when viewed from above the Z direction. The plurality of second electrodes may be positioned in parallel to correspond one-to-one with the plurality of unit filters 130R, 130G, and 130B when viewed from above in the Z direction.

Reflecting films 170a to 170c are interposed between the substrate 120 and each of the second electrodes 160a to 160c, the width of which is narrower than the width of the second electrode so that the reflecting film is embedded in the second electrode. . Accordingly, the reflective films 170a to 170c correspond to the transparent layers 140a to 140c in parallel, and the widths of the reflective films 170a to 170c are equal to each other. The reflective film is also preferably a metal film made of silver (Ag), silver alloy, aluminum (Al) or aluminum alloy.

First and second alignment layers 181 and 182 on which surfaces are rubbed are coated on the lower side of the first electrode layer 150 and the second electrode layer 160, respectively, and the liquid crystal layer 190 is interposed therebetween. Although not shown, a backlight may be installed under the substrate 120. In the present embodiment, each of the filters 130R, 130G, and 130B may have different areas depending on the degree of color implementation of the color filter layer.

In the reflective liquid crystal display 100, as a predetermined voltage is applied to the first and second electrode layers 150 and 160, the liquid crystal layer 190 is aligned in a predetermined pattern to selectively pass light to form an image. When the backlight is not required as in the daytime, the light passes through the liquid crystal layer 190 and is reflected by the reflective film 170, and then passes through the reflective region T2 of the liquid crystal layer 190 and the color filter layer 130. Color images are implemented. On the other hand, when a light source by the backlight is required, such as at night, the color image is realized by passing the light generated from the backlight through the transmission region T1 of the liquid crystal layer 190 and the color filter layer 130. As described above, since the transmission region T1 of the color filter layer 130 is formed to be relatively thicker than the reflection region T2, color reproducibility may be improved when the backlight is used.

4 is a plan view schematically showing a reflection film and an electrode formed on a substrate in the reflective liquid crystal display according to the present invention, and FIG. 5 is a view showing an electrode formed in a non-display area on the substrate in FIG. A cross-sectional view schematically. The cross-sectional view of the display area on the substrate is the same as in FIG.

Referring to the drawings, the second electrodes 160a to 160d extending in a stripe pattern parallel to each other on the substrate 120 are made of transparent ITO material, and the metal reflective films 170a to 170d are the same as those of the second electrode. It is embedded in a pattern. In forming the second electrodes 160a to 160d and the reflective films 170a to 170d, the second electrode is formed to extend to the non-display area D10 of the substrate, but the reflective film extends only to the display area D20. Therefore, in the non-display area D10, second electrodes 160a to 160d of ITO are directly deposited on the substrate 120 as shown in FIG. 5.

In comparison with the conventional reflective liquid crystal display device, in the non-display area D1 of the conventional reflective liquid crystal display device illustrated in FIG. 1, the ITO electrode is formed on the metallic reflective films 30a to 30d formed on the substrate 10. The films 20a to 20d are formed. Accordingly, the ITO electrode film formed on the metallic reflective film has a weaker film strength than when directly formed on the substrate, and the metallic reflective film serving as the supporting layer is also soft, so that the ITO electrode films 20a to 20d and the metallic reflective films 30a to 30d are formed. All of these have weak structural properties. In particular, the ITO electrode films 20a to 20d formed at the boundary with the metallic reflective films 30a to 30d have a poor film formation in which grain size is not dense.

In contrast, as shown in FIG. 5, in the non-display area D10 of the reflective LCD according to the present invention, since the ITO electrode layers 160a to 160d are directly deposited on the substrate 120, the strength of the electrode layer is relatively high. Has characteristics.

Since each of the electrode layers 160a to 160d has a small width, a short check probe having a corresponding sharp end should be used to check whether a pattern is shorted by the electrode layers. As described above, since the strength of the ITO electrode film in the non-display area D10 is stronger than that of the related art, damage to the electrode film can be prevented during a short test.

The reflective liquid crystal display of the present invention can prevent the ITO electrode film from being damaged during a short circuit inspection by directly depositing an ITO electrode film on the substrate without forming a metallic reflective film in the non-display area of the substrate.

In addition, a color image may be realized through the color filter layer, and in particular, by forming different thicknesses of the reflection area and the transmission area of the color filter layer, color reproducibility, color purity, and luminance of the image may be improved.

Although the present invention has been described with reference to the embodiments shown in the drawings, this is merely exemplary, and it will be understood by those skilled in the art that various modifications and equivalent other embodiments are possible. Therefore, the true scope of protection of the present invention should be defined only by the appended claims.

Claims (6)

A front plate provided with a non-display area at the periphery and a display area at the other center, the display panel being covered by the case and unable to project image light; A first electrode layer having a plurality of first electrodes formed on the bottom surface of the front plate in parallel with each other in a predetermined pattern; An edge bonded to the front plate to be spaced apart from the front plate, the substrate having a non-display area at a peripheral portion corresponding to the front plate and a display area at a central portion thereof; A second electrode layer having a plurality of second electrodes formed on the upper surface of the substrate in parallel with each other in a predetermined pattern; A reflective film disposed between each of the second electrodes and the display area of the substrate and having a width smaller than that of the second electrode so as to be embedded in the second electrode; First and second alignment layers coated on the bottom of the first electrode layer and on the second electrode layer, respectively; And And a liquid crystal layer injected between the first and second alignment layers, And the reflective film is formed only in the display area except for the non-display area of the substrate. The method of claim 1, And a color filter layer including a plurality of red, green, and blue unit filters formed in parallel with each other in a predetermined pattern between the front plate and the first electrode layer. The method of claim 2, The reflective liquid crystal display device further includes a transparent layer positioned between each unit filter and the front plate and having a width smaller than that of the unit filter so as to be embedded in the unit filter, and overlapping the transparent layer. A portion of the reflective liquid crystal display, characterized in that the thickness is relatively thinner than the other portion of the unit filter does not overlap the transparent layer. The method of claim 2 or 3, And the first electrode is perpendicular to each other and the second electrode is arranged in parallel to correspond one-to-one with the unit filter. The method according to any one of claims 1 to 3, And the second electrode is a transparent ITO electrode and the reflecting film is a metal film. The method of claim 5, wherein And the reflecting film is made of one of a group consisting of silver, silver alloy, aluminum, and aluminum alloy.

Images