CN101685226B - Liquid crystal display panel capable of improving color shift and liquid crystal display device using same - Google Patents

Abstract

A liquid crystal display panel and a liquid crystal display device capable of improving color cast are provided, the display panel comprises a first substrate and a second substrate which are arranged in parallel, and a liquid crystal layer is sealed between the first substrate and the second substrate. The first substrate includes a plurality of thin film transistors arranged in an array form, and each thin film transistor is disposed corresponding to a pixel unit of the liquid crystal display panel. The first substrate comprises a pixel electrode in each pixel unit, wherein the pixel electrode is electrically connected with the thin film transistor and is provided with a first electrode block and a second electrode block. The first electrode block is provided with a plurality of first slits, the first electrode block is provided with a first line distance in the direction perpendicular to the first slits, and the first electrode block is provided with a first line width between any two adjacent first slits. The second electrode block is provided with a plurality of second slits, the second electrode block is provided with a second line distance in the direction perpendicular to the second slits, and the second electrode block is provided with a second line width between any two adjacent second slits. The second pitch is substantially unequal to the first pitch.

Description

Liquid crystal display panel capable of improving color shift and liquid crystal display device using same

technical field

The present invention relates to a liquid crystal display panel and a liquid crystal display device using the same, and in particular to a liquid crystal display panel capable of improving color shift and a liquid crystal display device using the same.

Background technique

In recent years, flat-panel display technology has become more and more mature, and electronic products related to liquid crystal display panels have gained a relatively high market share. Among different types of liquid crystal display panels, vertical alignment (VA) liquid crystal display panels are more widely favored by manufacturers.

However, due to the structure of the VA-type liquid crystal display panel, it is easy to produce color washout phenomenon under large viewing angles, which makes the displayed images easy to be distorted, especially the appearance of human skin color tends to be relatively light blue or bright white. Therefore, how to solve the aforementioned color shift problem to provide users with better electronic products is actually one of the key considerations for manufacturers when manufacturing products.

Contents of the invention

The present invention relates to a liquid crystal display panel capable of improving color shift and a liquid crystal display device using the liquid crystal display device, so that a pixel unit can produce a superposition effect similar to two gamma curves (gamma curve) during display, so as to compensate for the color shift phenomenon , thereby improving the display effect.

The invention proposes a liquid crystal display panel capable of improving color shift, which includes a first substrate, a second substrate and a liquid crystal layer, wherein the liquid crystal layer is sealed between the first and second substrates arranged in parallel. The first substrate includes a plurality of thin film transistors arranged in an array, wherein each thin film transistor is arranged corresponding to the pixel unit of the liquid crystal display panel. The first substrate further includes a pixel electrode electrically connected to the thin film transistor in each pixel unit, and each pixel electrode has a first electrode block and a second electrode block. The first electrode block has a plurality of first slits, wherein the first electrode block has a first line pitch in a direction perpendicular to each of these first slits, and the first electrode block is in any two phases There is a first line width between adjacent first slits. The second electrode block has a plurality of second slits, wherein the second electrode block has a second pitch in a direction perpendicular to each of these second slits, and the second electrode block is between any two adjacent The second slits have a second line width between them. The second pitch is not substantially equal to the first pitch.

The invention further provides a liquid crystal display device, which includes a liquid crystal display panel and a light source module. The light source module is used for providing light source to the liquid crystal display panel. The liquid crystal display panel includes a first substrate and a second substrate arranged in parallel, wherein the liquid crystal layer is sealed between the first and second substrates. The first substrate includes a plurality of thin film transistors arranged in an array, wherein each thin film transistor is arranged corresponding to the pixel unit of the liquid crystal display panel. The first substrate further includes a pixel electrode electrically connected to the thin film transistor in each pixel unit, and each pixel electrode has a first electrode block and a second electrode block. The first electrode block has a plurality of first slits, wherein the first electrode block has a first line pitch in a direction perpendicular to each of these first slits, and the first electrode block is in any two phases There is a first line width between adjacent first slits. The second electrode block has a plurality of second slits, wherein the second electrode block has a second pitch in a direction perpendicular to each of these second slits, and the second electrode block is between any two adjacent The second slits have a second line width between them. The second pitch is not substantially equal to the first pitch.

In order to make the above content of the present invention more comprehensible, preferred embodiments are specifically cited below, together with the accompanying drawings, and described in detail as follows.

Description of drawings

FIG. 1 shows a schematic diagram of a liquid crystal display panel on its first substrate side according to a preferred embodiment of the present invention;

FIG. 2 is a schematic diagram showing the improvement of color shift produced by two gamma characteristic curves produced by the same pixel structure;

FIG. 3A shows a schematic diagram of a pixel unit collocated with a bump arrangement;

FIG. 3B shows a cross-sectional view of the pixel unit in FIG. 3A along the tangent line 3B-3B';

FIG. 4A shows a schematic diagram of a pixel unit with two bumps;

FIG. 4B shows a cross-sectional view of the pixel unit in FIG. 4A along the tangent line 4B-4B';

FIG. 4C is a schematic diagram of two pixel blocks of a pixel unit corresponding to bumps;

FIG. 5A shows a perspective view of a general vertical alignment product;

FIG. 5B shows a perspective view of a single bump collocated with a slit in this embodiment;

6A shows a characteristic curve of voltage versus transmittance (V-T) observed at a viewing angle of 60 degrees with a single bump design;

FIG. 6B shows a gamma characteristic curve observed at a viewing angle of 60 degrees with a single bump design;

FIG. 7A shows a V-T characteristic curve observed at a viewing angle of 60 degrees with two bump designs;

FIG. 7B shows a gamma characteristic curve observed at a viewing angle of 60 degrees with two bump designs.

Description of main component symbols

10: Liquid crystal display panel

100: first substrate

110, 120, 130: pixel electrodes

112, 122, 132: first electrode block

112S, 122S, 132S: the first slit

114, 124, 134: second electrode block

114S, 124S, 134S: Second slit

200: second substrate

210, 220, 230: bumps

L: line spacing

L1: first line distance

L2: second line distance

W: line width

W1: first line width

W2: second line width

P1, P2, P3: pixel units

T1, T2, T3: thin film transistors

Detailed ways

The liquid crystal display panel and the liquid crystal display device using it proposed in this embodiment divide each pixel unit into two display areas, and the pixel electrodes of each pixel unit have different line widths in the two display areas. The slit design of line spacing makes it possible to display different transmittances in the two display areas under the same driving voltage. In addition, the arrangement of protrusions can be properly matched to assist the alignment of liquid crystal molecules.

The liquid crystal display panel of this embodiment includes a first substrate, a second substrate and a liquid crystal layer, wherein the liquid crystal layer is sealed between the first substrate and the second substrate arranged in parallel. In this embodiment, the first substrate is, for example, a thin film transistor substrate for illustration, and the second substrate is, for example, a color filter substrate.

Please refer to FIG. 1 , which shows a schematic diagram of a liquid crystal display panel on its first substrate side according to a preferred embodiment of the present invention. The first substrate 100 of the liquid crystal display panel 10 includes a plurality of thin film transistors arranged in an array, such as thin film transistors T1 to T3 arranged in the same column, wherein the thin film transistors T1 to T3 respectively correspond to the pixel unit P1 of the liquid crystal display panel 10 to P3 settings. A plurality of data lines and scan lines (not shown) are further provided on the first substrate 100, wherein, for example, the data lines are arranged in the first substrate 100 along the longitudinal edges of the pixel units P1 to P3, and are electrically connected For the thin film transistors T1 to T3 , the scanning lines are, for example, arranged laterally along the thin film transistor configuration regions of the pixel units P1 to P3 .

The first substrate 100 also includes pixel electrodes 110 to 130 in the pixel units P1 to P3, which are electrically connected to the thin film transistors T1 to T3, wherein the pixel electrode 110 has a first electrode area 112 and a second electrode area. Block 114 , the pixel electrode 120 has a first electrode block 122 and a second electrode block 124 , and the pixel electrode 130 has a first electrode block 132 and a second electrode block 134 . The first electrode blocks 112 , 122 , 132 and the second electrode blocks 114 , 124 , 134 are, for example, respectively disposed on two sides of the thin film transistors T1 to T3 . Each of the first electrode blocks 112 , 122 , 132 has a plurality of first slits 112S, 122S, 132S, and each of the second electrode blocks 114 , 124 , 134 has a plurality of second slits 114S, 124S, 134S. The first electrode blocks 112, 122, 132 have a first line distance L1 in the vertical direction of each first slit 112S, 122S, 132S, and the first electrode blocks 112, 122, 132 are located between any two adjacent There is a first line width W1 between the first slits 112S, 122S, 132S. The second electrode blocks 114, 124, 134 have a second line distance L2 in the second slits 114S, 124S, 134S, and have a second line width between any two adjacent second slits 114S, 124S, 134S W2, wherein the second line distance L2 is not equal to the first line distance L1 so that the first electrode blocks 112 , 122 , 132 and the second electrode blocks 114 , 124 , 134 have different light transmittances.

In addition, the second line width W2 can also be different from the first line width W1 , and the first electrode blocks 112 , 122 , 132 and the second electrode blocks 114 , 124 , 134 can also have different light transmittance effects. Since the first electrode blocks 112, 122, 132 and the second electrode blocks 114, 124, 134 have different line widths or line distances, preferably, the first electrode block of a pixel unit corresponds to an adjacent pixel unit The arrangement of the second electrode blocks, that is, the first electrode blocks and the second electrode blocks on the entire first substrate 100 are arranged alternately upside down and upside down. As shown in FIG. 1 , the left and right sides of the first electrode block 122 are respectively the second electrode blocks 114 and 134 , and the left and right sides of the second electrode block 124 are respectively the first electrode blocks 112 and 132 .

Although a single pixel unit is divided into two display areas, both the first pixel block and the second pixel block are controlled by the same thin film transistor, so they actually receive the same pixel driving voltage. Since the first electrode block and the second electrode block have different line widths or line distances, the two display regions will have different transmittances relative to a common electrode driving voltage, so that a pixel unit has two Gamma characteristic curve (gamma curve). Please refer to FIG. 2 , which shows a schematic diagram of improving color shift produced by the same pixel structure with two gamma characteristic curves. The gamma characteristic curve of the display area corresponding to the first pixel block is, for example, curve C1 , and the gamma characteristic curve of the display area corresponding to the second pixel block is, for example, curve C2 . The characteristic curve C3 after the superposition of the two clearly shows that the design of the pixel structure does have the effect of modulating the gamma characteristic curve.

In addition, since the first pixel block and the second pixel block of two adjacent pixel units are alternately arranged upside down, it can effectively provide symmetric compensation of the liquid crystal director in four directions, so as to avoid when the first pixel block and the second pixel block The line spacing and line width of the second pixel block are different, resulting in a stripe defect that may be generated when the transmittance is greatly different.

A plurality of bumps can also be disposed on the second substrate of the liquid crystal display panel 10 to match the aforementioned first slits and second slits. Please refer to FIGS. 3A and 3B . FIG. 3A shows a schematic diagram of a pixel unit with a bump arrangement, and FIG. 3B shows a cross-sectional view of the pixel unit in FIG. 3A along the line 3B-3B'. Taking the pixel unit P1 as an example, a bump 210 can be provided on the second substrate 200 facing the first substrate 100, wherein the bump 210 is arranged corresponding to the first pixel block 112 of the pixel unit P1 to assist the second The liquid crystal molecules in the center of the display area corresponding to a pixel block 112 are aligned. And preferably, the bump 210 substantially corresponds to the middle position of the two first slits 112S in the center of the first pixel block 112 . In addition, another bump (not shown) may also be disposed on the second substrate 200 corresponding to the middle position of the two second slits in the center of the second pixel block 114 .

Please also refer to FIGS. 4A and 4B. FIG. 4A shows a schematic diagram of a pixel unit with two bumps, and FIG. 4B shows a cross-sectional view of the pixel unit in FIG. 4A along the line 4B-4B'. Also taking the pixel unit P1 as an example, two bumps 220 and 230 may be disposed on the second substrate 200 . The bumps 220 , 230 are arranged at two opposite corners corresponding to the edge of the second pixel block 114 to assist the alignment of the liquid crystal molecules at the edge of the display area.

FIG. 4C is a schematic diagram of bumps corresponding to two pixel blocks of a pixel unit. In FIG. 4C , the two above-mentioned bump arrangement methods are used in combination, wherein the center of the first pixel block 112 is set corresponding to the bump 210, and the two edge corners of the second pixel block 114 are respectively corresponding to The bumps 220, 230 are provided.

The following is by adjusting the line width or line spacing of the pixel blocks in the two display areas (making the size ratio about 1:1), and making the extension direction of the slit coincide with the scanning line (or the horizontal axis direction of the pixel unit) ) is about 45 degrees, driven by the same voltage, so that the two display areas have different distributions of electric field lines in the two pixel blocks due to different line width or line spacing designs, resulting in differences in the orientation of the liquid crystal directors, resulting in different presentations The transmittance, and at the same time compared with the general vertical alignment (vertical alignment, VA) type products to observe the characteristic curve.

Please refer to FIGS. 5A and 5B . FIG. 5A shows a perspective view of a general vertical alignment product, and FIG. 5B shows a perspective view of a single bump collocated with a slit in this embodiment. Please also refer to FIGS. 6A and 6B. FIG. 6A shows the characteristic curve of voltage versus transmittance (V-T) observed at a viewing angle of 60 degrees with a single bump design in this embodiment, and FIG. 6B shows a single bump design at a viewing angle of 60 degrees. The gamma characteristic curve of the observation. Under the condition of a single bump setting, as shown in Figure 5B, the line width W and line distance L are all 1, 3, 4, 5um and the V-T characteristic curves of general VA products at 0° and 60° viewing angles are compared. Recorded in Figure 6A. As shown in Figure 5A, the bumps and slits on the top and bottom of the VA-type substrate are generally matched one-to-one. The width of the bump is about 10um, the size of the slit is about 8um, and the width of the electrode between the slits is about 30um. . In Fig. 6A, curve 601 is the V-T characteristic curve of general VA products at 60 degrees, curves 602 to 605 are the V-T characteristic curves of line width W and line distance L at 60 degrees at 60 degrees, and curve 606 It is the V-T characteristic curve of general VA products at 0 degrees. In Figure 6B, curve 701 is a curve with a gamma value of 2.2, curve 702 is a gamma characteristic curve measured at 60 degrees for general VA products based on the above parameters, and curve 703 is based on the line width W and line distance L being 4um The V-T characteristic curve is used to make the Gamma characteristic curve, and the other curves 704 to 707 are described below.

It can be seen from FIG. 6A that when the line width W and the line distance L are both 4um, a V-T characteristic curve 604 similar to that of a 0-degree viewing angle (curve 606 ) can be generated at a viewing angle of 60 degrees. In Fig. 6B, the curve 702 is the gamma characteristic curve of general VA products at 60 degrees, the curve 703 is the gamma characteristic curve made according to the V-T characteristic curve with the line width W and the line distance L being 4um, and the curve 704 to 707 , which are the gamma characteristic curves obtained by superimposing the above two pixel block area ratios of 1:1, 1:2, 3:7, and 2:8 respectively. The purpose of superimposing the two is to superimpose and adjust the gamma characteristic curves that originally fall above and below the gamma value 2.2 curve to produce another set of new gamma characteristic curves that are closer to the gamma value 2.2 curve. It can be observed from the results in FIG. 6B that the superimposed effects of the two (curves 704 to 707 ) are closer to the curve 701 with a gamma value of 2.2 than the gamma characteristic curve 702 of general VA products. In addition, the curve obtained by using only the design proposed in this embodiment is similar to the curve 703 in FIG. 6B , which is quite close to the curve 701 with a gamma value of 2.2. The gamma characteristic curve is similar to the gamma characteristic curve under the normal viewing angle. Therefore, this embodiment greatly reduces the color shift phenomenon of general VA products by adjusting the line width W or line distance L in the two display areas, and controlling the area ratio of the pixel block, and matching with the design of a single bump.

FIG. 7A shows a V-T characteristic curve observed at a viewing angle of 60 degrees with two bumps designed, and FIG. 7B shows a gamma characteristic curve observed at a viewing angle of 60 degrees with two bumps designed. Under the condition of setting two bumps, the line width and line spacing are 0.5, 1, 3, 4, 5um (respectively recorded in curves 801 to 805) and general VA products at 0 degrees (curve 807) and 60 degrees A comparison of the V-T characteristics of the viewing angle (curve 806) is reported in FIG. 7A. As can be seen from Figure 7A, when the line width and line spacing are both 3um, a V-T characteristic curve (curve 806) similar to the symmetric V-T characteristic curve (curve 806) of a general VA product at a viewing angle of 60 degrees can be produced at a viewing angle of 60 degrees. 803). In FIG. 7B , the gamma characteristic curve is made according to the V-T characteristic curve (curve 803 ) whose line width and line spacing are both 3um. Curve 901 is the curve with a gamma value of 2.2, curve 902 is the gamma characteristic curve of general VA products at 60 degrees, and curve 903 is the gamma characteristic curve made according to the V-T characteristic curve with a line width and line spacing of 3um , the curves 904 to 908 are curves obtained by superimposing the area ratios of the aforementioned two pixel blocks at 1:1, 8:2, 2:8, 9:1 and 1:9 respectively. In FIG. 7B , the curve 903 is close to the bottom right. When superimposed, it can be found that the superimposed curves 904 to 908 are more Gamma than the Gamma characteristic curve 902 of general VA products at large viewing angles. The value 2.2 curve 901 approaches. Therefore, in this embodiment, the color shift phenomenon can be effectively improved by adjusting the line width or line spacing in the two display areas, and controlling the area ratio of the pixel block, and matching with the design of two bumps.

The liquid crystal display panel 10 of this embodiment can be applied in a liquid crystal display device, and the light source module installed in the liquid crystal display device provides light to the liquid crystal display panel 10 for display. Since this embodiment divides each pixel unit into two display areas, and adjusts the line width or line distance of the pixel electrodes in the two display areas, it can be solved whether it is matched with a single bump or two bumps. Traditionally, the color shift problem of VA products under large viewing angles has improved the quality of the picture display. In addition, because only the structure of the pixel electrode is changed, no additional process and cost are required, and the original process sequence will not be affected. Furthermore, the pixel blocks in the two display areas are controlled by a single thin film transistor, so there is no need to add other thin film transistors, which avoids affecting the size of the aperture ratio.

Although the first substrate and the second substrate of the liquid crystal display panel 10 in this embodiment are respectively described as an example of a thin film transistor substrate and a color filter substrate, the present invention is not limited thereto. The design of the structure of the pixel electrode in this embodiment can also be applied to other types of liquid crystal display panels, as long as a single pixel unit is divided into two display areas, and the line width or line width of the pixel electrodes in the two display areas There is a difference in pitch to adjust the transmittance of the two display areas, combined with the control of the pixel block area ratio, so that the gamma characteristic curve of the larger viewing angle can approach the curve of the gamma value of 2.2 at the front viewing angle, all of which belong to scope of the invention.

In summary, although the present invention has been disclosed as above with preferred embodiments, it is not intended to limit the present invention. Those skilled in the art of the present invention can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention should be determined by what is defined by the claims.

Claims (20)

1. A liquid crystal display panel capable of improving color shift, comprising: The first substrate includes a plurality of thin film transistors arranged in an array, and each of the thin film transistors is set corresponding to the pixel unit of the liquid crystal display panel, wherein the first substrate is also electrically connected to the pixel unit in each pixel unit. A pixel electrode of a thin film transistor, the pixel electrode has: a first electrode block with a plurality of first slits, wherein the first electrode block has a first slit in a direction perpendicular to each of the first slits a line pitch, and the first electrode block has a first line width between any two adjacent first slits; and a second electrode block has a plurality of second slits, wherein the second The electrode block has a second line spacing in a direction perpendicular to each of the second slits, and the second electrode block has a second line width between any two adjacent second slits, wherein the the second line spacing is not equal to the first line spacing; a second substrate disposed parallel to the first substrate; and The liquid crystal layer is sealed between the first substrate and the second substrate. 2. The liquid crystal display panel as claimed in claim 1, wherein the first line width is not equal to the second line width. 3. The liquid crystal display panel as claimed in claim 1, wherein the first electrode block of the pixel electrode of one pixel unit corresponds to the second electrode block of the pixel electrode of another adjacent pixel unit, and these pixel units are Pixel cells located in the same column or pixel cells located in the same row. 4. The liquid crystal display panel as claimed in claim 1, wherein a plurality of bumps are disposed on the surface of the second substrate facing the first substrate, and each pixel unit corresponds to at least one bump. 5. The liquid crystal display panel as claimed in claim 4, wherein the first electrode area of the pixel electrode of each pixel unit corresponds to a bump. 6. The liquid crystal display panel as claimed in claim 5, wherein the protrusion corresponds to a middle position between the two first slits in the center of the first electrode block. 7. The liquid crystal display panel as claimed in claim 5, wherein the second electrode block of the pixel electrode of each pixel unit corresponds to another bump, and the other bump corresponds to the central two electrodes of the second electrode block. The middle position of the second slit. 8. The liquid crystal display panel as claimed in claim 4, wherein the first electrode area of the pixel electrode of each pixel unit corresponds to two bumps. 9. The liquid crystal display panel as claimed in claim 8, wherein the outline of the first electrode block has two diagonal corners, and the two bumps respectively correspond to the two diagonal corners. 10. The liquid crystal display panel as claimed in claim 8, wherein the second electrode block of the pixel electrode of each pixel unit corresponds to the other two bumps, the outline of the second electrode block has two diagonal corners, and the other The two bumps correspond to the two diagonal corners. 11. A liquid crystal display device, comprising: Liquid crystal display panel, including: The first substrate includes a plurality of thin film transistors arranged in an array, and each of the thin film transistors is set corresponding to a pixel unit of the liquid crystal display panel, wherein the first substrate further includes a pixel electrode system electrical Connected to the thin film transistor in the pixel unit, the pixel electrode has: a first electrode block with a plurality of first slits, wherein the first electrode block has a direction perpendicular to each of the first slits and the first electrode block has a first line width between any two adjacent first slits; and the second electrode block has a plurality of second slits, wherein , each of the second electrode blocks has a second pitch in a direction perpendicular to each of the second slits, and the second electrode block has a first pitch between any two adjacent second slits Two line widths, wherein the second line distance is not equal to the first line distance; a second substrate disposed parallel to the first substrate; and a liquid crystal layer sealed between the first substrate and the second substrate; and The light source module is used for providing light source to the liquid crystal display panel. 12. The liquid crystal display device as claimed in claim 11, wherein the first line width is not equal to the second line width. 13. The liquid crystal display device as claimed in claim 11, wherein the first electrode block of the pixel electrode of one pixel unit corresponds to the second electrode block of the pixel electrode of another adjacent pixel unit, and these pixel units are Pixel cells located in the same column or pixel cells located in the same row. 14. The liquid crystal display device as claimed in claim 11, wherein a plurality of bumps are disposed on a surface of the second substrate facing the first substrate, and each pixel unit corresponds to at least one bump. 15. The liquid crystal display device as claimed in claim 14, wherein the first electrode block of the pixel electrode of each pixel unit corresponds to a bump. 16. The liquid crystal display device as claimed in claim 15, wherein the protrusion corresponds to a middle position between the two first slits in the center of the first electrode block. 17. The liquid crystal display device as claimed in claim 15, wherein the second electrode block of the pixel electrode of each pixel unit corresponds to another bump, and the other bump corresponds to the central two electrodes of the second electrode block. The middle position of the second slit. 18. The liquid crystal display device as claimed in claim 14, wherein the first electrode area of the pixel electrode of each pixel unit corresponds to two bumps. 19. The liquid crystal display device as claimed in claim 18, wherein the contour of the first electrode block has two diagonal corners, and the two bumps correspond to the two diagonal corners respectively. 20. The liquid crystal display device as claimed in claim 18, wherein the second electrode block of the pixel electrode of each pixel unit corresponds to the other two bumps, the outline of the second electrode block has two diagonal corners, and the other two The two bumps correspond to the two diagonal corners.

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