TWI888041B - Cholesteric liquid crystal panel - Google Patents

Abstract

Disclosed is a cholesteric liquid crystal panel, which comprises a lower transparent substrate, at least one signal line, an organic layer, a plurality of pixel electrodes, a liquid crystal layer and an upper substrate. The signal line is disposed on the lower transparent substrate, the organic layer is disposed on the signal line, the pixel electrodes are disposed on the organic layer, the liquid crystal layer is disposed on the pixel electrodes, the upper substrate is disposed on the liquid crystal layer. The space between the pixel electrodes is less than or equal to the width of the signal line. The area of ​​the pixel electrodes increases by narrowing the spacing between the pixel electrodes. The configuration of a black matrix is not necessary, and thus the aperture ratio and brightness of the cholesterol liquid crystal panel are increased.

Description

Cholesterol LCD Panel

The present invention relates to a liquid crystal panel, in particular to a cholesterol liquid crystal panel.

Reflective liquid crystal panels do not require a backlight module to provide light, so they have the characteristics of thinness and low power consumption. In recent years, they have been applied to various electronic products. Among them, cholesterol liquid crystals are gradually being applied to full-color display panels because they can selectively reflect ambient light of certain wavelengths and have the characteristics of a bistable state.

Referring to FIG. 8 and FIG. 9 , the conventional cholesterol liquid crystal panel includes an array substrate 500, a cholesterol liquid crystal layer 600, an upper transparent electrode layer 700 and an upper transparent substrate 800 stacked in sequence from bottom to top. The array substrate 500 is used to provide an electric field applied to the cholesterol liquid crystal layer 600. The array substrate 500 can further The step includes a lower transparent substrate 510, an active device array 520, a passivation layer 530 and a plurality of pixel electrodes 540, wherein the active device array 520 is disposed on the lower transparent substrate 510, and the passivation layer 530 is disposed on the active device array 520. The material used for the passivation layer 530 is mostly silicon nitride. nitride), silicon oxide or silicon oxynitride, and the pixel electrodes 540 are disposed on the passivation layer 530; usually, the active device array 520 includes a plurality of active devices 521, a plurality of gate lines 522 and a plurality of source lines 523, and the active devices 521 are arranged in an array and electrically connected to the gate lines 522 and the source lines 523, respectively.

As shown in FIG8 and FIG9, since each gate line 522/source line 523 usually has a higher conduction voltage, each gate line 522/source line 523 must have a certain distance from each pixel electrode 540 to prevent the electric lines generated by each gate line 522/source line 523 from interfering with the electrical properties of each pixel electrode 540, causing the cholesterol liquid crystal in the cholesterol liquid crystal layer 600 to be arranged in disorder. However, this reduces the area of each pixel electrode 540, and the cholesterol liquid crystal between adjacent pixel electrodes 540 is prone to be arranged unevenly without electric field control, thereby affecting the transmittance of the cholesterol liquid crystal panel.

Therefore, in the prior art, a black matrix 900 is usually provided between the upper transparent electrode layer 700 and the upper transparent substrate 800. The black matrix 900 is located between adjacent pixel electrodes 540 to shield the unevenly arranged cholesterol liquid crystals between the pixel electrodes 540 and improve the transmittance problem. However, the provision of the black matrix 900 allows the shielded part of the ambient light to penetrate, thereby causing the aperture ratio of the cholesterol liquid crystal panel to decrease and the brightness to decrease.

Therefore, it is necessary to propose a better solution to solve the above-mentioned shortcomings of the prior art.

In view of the above-mentioned shortcomings of the prior art, the main purpose of the present invention is to provide a cholesterol liquid crystal panel, which improves the aperture ratio and brightness of the cholesterol liquid crystal panel through the improved structure of the cholesterol liquid crystal panel.

To achieve the above-mentioned purpose, the main technical means adopted by the present invention is to make the above-mentioned cholesterol liquid crystal panel include: A lower transparent substrate; One or more signal lines are arranged on the lower transparent substrate, and the signal lines have a width; A plurality of active elements are electrically connected to the signal lines; An organic layer is arranged on the signal lines and the active elements; A plurality of pixel electrodes are arranged on the organic layer, and there is a spacing between adjacent pixel electrodes, and the position of the spacing between adjacent pixel electrodes corresponds to the signal lines; A liquid crystal layer is arranged on the pixel electrodes; An upper substrate is arranged on the liquid crystal layer; The spacing between adjacent pixel electrodes is less than or equal to the width of the signal lines.

The present invention uses the above structure to set the organic layer on the signal lines, and utilizes the material and thickness characteristics of the organic layer to isolate the pixel electrodes from the signal lines. In addition, by narrowing the distance between adjacent pixel electrodes, the area of the pixel electrode is expanded without setting a black matrix, thereby achieving the purpose of improving the aperture ratio and brightness of the cholesterol liquid crystal panel.

Regarding the embodiment of the cholesterol liquid crystal panel of the present invention, please refer to FIG. 1 to FIG. 4, which includes a lower transparent substrate 10, more than one signal line 20, a plurality of active elements 80, an organic layer 30, a plurality of pixel electrodes 40, a liquid crystal layer 50 and an upper substrate 60. The lower transparent substrate 10 is rectangular and has a first side 11 and a second side 12 that are parallel to each other. The signal lines 20 are disposed on the lower transparent substrate 10. The active elements 80 are arranged in an array and are electrically connected to the signal lines 20. , the organic layer 30 is disposed on the signal lines 20 and the active elements 80, the pixel electrodes 40 are disposed on the organic layer 30, the liquid crystal layer 50 is disposed on the pixel electrodes 40, and the upper substrate 60 is disposed on the liquid crystal layer 50; the signal lines 20 have a width, and there is a distance between adjacent pixel electrodes 40, and the distance between adjacent pixel electrodes 40 is located at a position corresponding to the signal lines 20, wherein the distance between adjacent pixel electrodes 40 is less than or equal to the width of the signal line 20. In this embodiment, the liquid crystal layer 50 may be composed of a cholesterol liquid crystal layer.

By means of the above structure, the pixel electrodes 40 and the signal lines 20 are isolated by the organic layer 30, and the distance between adjacent pixel electrodes 40 is narrower, so that the area of the pixel electrodes 40 is enlarged without setting a black matrix, thereby improving the aperture ratio and brightness of the cholesterol liquid crystal panel. In this embodiment, a horizontal direction X and a vertical direction Y are further provided, the horizontal direction X is perpendicular to the vertical direction Y, and the horizontal direction X is parallel to the first side 11 of the lower transparent substrate 10, and the vertical direction Y is parallel to the second side 12 of the lower transparent substrate 10.

As shown in FIGS. 1 to 3 , in the present embodiment, the signal lines 20 further include one or more gate lines 21 and one or more source lines 22. The gate lines 21 are disposed on the lower transparent substrate 10 and are parallel to each other. In the present embodiment, the gate lines 21 are parallel to the horizontal direction X. The source lines 22 are perpendicular to the gate lines 21. In the present embodiment, the source lines 22 are parallel to the vertical direction Y. Furthermore, the pixel electrodes 40 are disposed between the adjacent gate lines 21 and between the adjacent source lines 22. In the present embodiment, the pixel electrodes 40 are arranged in an array and are rectangular in shape.

In the present embodiment, the width of the signal lines 20 further includes a first width _W1 and a second width _W2 , the gate lines 21 of the signal lines 20 have the first width _W1 in the vertical direction Y, and the source lines 22 of the signal lines 20 have the second width _W2 in the horizontal direction X. In the present embodiment, the spacing between adjacent pixel electrodes 40 further includes a first spacing _S1 and a second spacing _S2 , in the vertical direction Y, the adjacent pixel electrodes 40 have the first spacing _S1 ; in the horizontal direction X, the adjacent pixel electrodes 40 have the second spacing _S2 .

Still as shown in FIG. 1 to FIG. 3 , in this embodiment, the pixel electrodes 40 may extend in the vertical direction Y and partially overlap the gate lines 21, so that the first spacing _S1 between adjacent pixel electrodes 40 is less than the first width _W1 of the gate lines 21; or the pixel electrodes 40 may be aligned with the gate lines 21, so that the first spacing _S1 between adjacent pixel electrodes 40 is equal to the first width _W1 of the gate lines 21, thereby achieving the effect of expanding the area of the pixel electrodes. In this embodiment, the first spacing _S1 is greater than or equal to 1 micrometer (μm).

In the present embodiment, the pixel electrodes 40 may also extend in the horizontal direction X and partially overlap with the source lines 22, so that the second spacing _S2 between adjacent pixel electrodes 40 is smaller than the second width _W2 of the source lines 22; or the pixel electrodes 40 may also be aligned with the source lines 22, so that the second spacing _S2 between adjacent pixel electrodes 40 is equal to the second width _W2 of the source lines 22, thereby achieving the effect of expanding the area of the pixel electrodes. In the present embodiment, the second spacing _S2 is greater than or equal to 1 micrometer.

As shown in FIG. 2 and FIG. 3 , in this embodiment, the present invention further provides a first passivation layer 70, the first passivation layer 70 covers the lower transparent substrate 10 and the gate lines 21, and the source lines 22 are disposed on the first passivation layer 70, and the organic layer 30 covers the first passivation layer 70 and the source lines 22. In addition, in this embodiment, the material used for the organic layer 30 may include a polyimide resin, an epoxy resin or an acrylic resin. In this embodiment, the organic layer 30 has a first thickness _T1 , and the first thickness _T1 is between 0.3 micrometers and 10 micrometers.

As shown in FIG. 3 , in this embodiment, the upper substrate 60 further includes an upper transparent electrode layer 61 and an upper transparent substrate 62 . The upper transparent electrode layer 61 is disposed on the liquid crystal layer 50 , and the upper transparent substrate 62 is disposed on the upper transparent electrode layer 61 .

4 and 5 , in this embodiment, the active devices 80 are electrically connected to the corresponding gate line 21 and the corresponding source line 22. In this embodiment, each active device 80 includes a gate 81, a channel layer 82, a source 83 and a drain 84.

The gate 81 is disposed on the lower transparent substrate 10 and is electrically connected to the corresponding gate line 21; the aforementioned first passivation layer 70 covers the gate 81; the channel layer 82 is disposed on the first passivation layer 70; the source 83 and the drain 84 respectively cover and electrically connect the opposite sides of the channel layer 82, and the source 83 is electrically connected to the corresponding source line 22; the organic layer 30 covers the channel layer 82, the source 83 and the drain 84.

As shown in FIG. 4 and FIG. 5 , in the present embodiment, the organic layer 30 has a plurality of openings 31, and the openings 31 respectively expose the drains 84 of the active elements 80. The pixel electrodes 40 are disposed on the organic layer 30 and are electrically connected to the drains 84 of the active elements 80 through the openings 31 of the organic layer 30.

In addition, referring to FIG. 4 to FIG. 6 , in this embodiment, the present invention further provides a second passivation layer 90, which covers the first passivation layer 70, the source lines 22, and the channel layer 82, the source 83, and the drain 84 of the active elements 80, and the organic layer 30 covers the second passivation layer 90. By disposing the first passivation layer 70 and the second passivation layer 90 above and below the channel layer 82 of the active elements 80, respectively, the leakage problem of the active elements 80 is avoided. As shown in FIG. 6 , in this embodiment, the second passivation layer 90 has a second thickness T ₂ , and the second thickness T ₂ is between 0.3 micrometers and 3 micrometers.

As shown in FIG. 7 , the active element can further have a variety of shapes, including an active element 80A, an active element 80B, an active element 80C, an active element 80D, an active element 80E, an active element 80F, or an active element 80G. In one shape of the present embodiment, the source 83A, 83B, 83C and the drain 84A, 84B, 84C of the active element 80A, 80B, 80C are I-shaped on one side. In another shape of the present embodiment, the source 83D, 83E of the active element 80D, 80E is U-shaped on one side, and the drain 84D, 84E of the active element 80D, 80E is I-shaped on one side. As shown in the next embodiment, the source 83F, 83G and the drain 84F, 84G of the active element 80F, 80G are J-shaped on one side.

10: lower transparent substrate 11: first side 12: second side 20: signal line 21: gate line 22: source line 30: organic layer 31: opening 40: pixel electrode 50: liquid crystal layer 60: upper substrate 61: upper transparent electrode layer 62: upper transparent substrate 70: first passivation layer 80, 80A, 80B, 80C, 80D, 80E, 80F, 80G: active element 81: gate 82: channel layer 83, 83A, 83B, 83C, 83D, 83E, 83F, 83G: source 84, 84A, 84B, 84C, 84D, 84E, 84F, 84G: drain 90: second passivation layer _S1 : first spacing S ₂ : second spacing W ₁ : first width W ₂ : second width T ₁ : first thickness T ₂ : second thickness X: horizontal direction Y: vertical direction 500: array substrate 510: lower transparent substrate 520: active device array 521: active device 522: gate line 523: source line 530: passivation layer 540: pixel electrode 600: cholesterol liquid crystal layer 700: upper transparent electrode layer 800: upper transparent substrate 900: black matrix

FIG1 is a schematic diagram of an embodiment of the cholesterol liquid crystal panel of the present invention; FIG2 is a cross-sectional view of the embodiment of FIG1 of the present invention along the A-A’ line segment; FIG3 is a cross-sectional view of the embodiment of FIG1 of the present invention along the B-B’ line segment; FIG4 is another schematic diagram of an embodiment of the cholesterol liquid crystal panel of the present invention; FIG5 is a cross-sectional view of the embodiment of FIG4 of the present invention along the C-C’ line segment; FIG6 is another cross-sectional view of the embodiment of FIG4 of the present invention along the C-C’ line segment; FIG7 is a schematic diagram of different states of active elements of various embodiments of the present invention; FIG8 is a schematic diagram of an embodiment of an existing cholesterol liquid crystal panel; FIG9 is a cross-sectional view of the embodiment of FIG8 of the existing cholesterol liquid crystal panel along the D-D’ line segment.

10: Lower transparent substrate

11: First side

12: Second side

20:Signal cable

21: Gate line

22: Source line

40: Pixel electrode

S ₁ : First spacing

S ₂ : Second spacing

W ₁ : First width

W ₂ : Second width

X: horizontal direction

Y: vertical direction

Claims (9)

A cholesterol liquid crystal panel includes: A lower transparent substrate; One or more signal lines are arranged on the lower transparent substrate, and the signal lines have a width; A plurality of active elements are electrically connected to the signal lines; An organic layer is arranged on the signal lines and the active elements; A plurality of pixel electrodes are arranged on the organic layer, and there is a spacing between adjacent pixel electrodes, and the position of the spacing between adjacent pixel electrodes corresponds to the signal lines; A liquid crystal layer is arranged on the pixel electrodes; An upper substrate is arranged on the liquid crystal layer; Wherein, the spacing between adjacent pixel electrodes is less than or equal to the width of the signal lines; The signal lines further include one or more gate lines and one or more source lines, the source lines are perpendicular to the gate lines, and the pixel electrodes are disposed between adjacent gate lines and between adjacent source lines. The cholesterol liquid crystal panel as described in claim 1, wherein the pixel electrodes partially overlap with the gate lines respectively, so that the distance between adjacent pixel electrodes is smaller than the width of the gate lines. The cholesterol liquid crystal panel as described in claim 1, wherein the pixel electrodes are aligned with the gate lines respectively so that the distance between adjacent pixel electrodes is equal to the width of the gate lines. A cholesterol liquid crystal panel as described in claim 1, wherein the pixel electrodes partially overlap with the source lines respectively, so that the distance between adjacent pixel electrodes is smaller than the width of the source lines. A cholesterol liquid crystal panel as described in claim 1, wherein the pixel electrodes are aligned with the source lines respectively so that the distance between adjacent pixel electrodes is equal to the width of the source lines. The cholesterol liquid crystal panel as described in claim 1, wherein the organic layer has a first thickness, and the first thickness is comprised between 0.3 micrometers and 10 micrometers. The cholesterol liquid crystal panel as described in claim 1 further comprises a first passivation layer, wherein the first passivation layer covers the lower transparent substrate and the gate lines, and the source lines are arranged on the first passivation layer, and the organic layer covers the first passivation layer and the source lines. The cholesterol liquid crystal panel as described in claim 7 further comprises a second passivation layer, wherein the second passivation layer covers the first passivation layer, the source lines and the active elements, and the organic layer covers the second passivation layer. A cholesterol liquid crystal panel as described in claim 8, wherein the second passivation layer has a second thickness, and the second thickness is comprised between 0.3 microns and 3 microns.

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