Thin film transistor array panel and method for manufacturing the same

• US 20070002251A1
• Filed: 07/03/2006
• Published: 01/04/2007
• Est. Priority Date: 07/04/2005
• Status: Active Grant

• Current Assignee: Samsung Display Company Limited (Samsung Electronics Co. Ltd.)
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Kim, Hyun-Wuk, Yoo, Seung-Hoo, Do, Hee-Wook, Chang, Hak-Sun, Um, Yoon-Sung
• Granted Patent: US 8,018,411 B2
• Time in Patent Office: Days
• US Class Current: 349/141
• CPC Class Codes: G02F 1/134363 for applying an electric field parallel to the substrate, i.e. in-plane switching [IPS]
• CPC Class Codes: G09G 2320/0252 Improving the response speed
• CPC Class Codes: G09G 2340/16 Determination of a pixel data signal depending on the signal applied in the previous frame
• CPC Class Codes: G09G 3/2011 by amplitude modulation
• CPC Class Codes: G09G 3/3648 using an active matrix G09G3/367 - G09G3/3696 take precedence

Abstract

A liquid crystal display device having a first substrate and a second substrate facing the first substrate, a liquid crystal layer interposed between the first substrate and the second substrate, a pixel electrode formed over the first substrate, a common electrode formed over the first substrate with insulating from the pixel electrode, wherein a portion of the common electrode overlaps with the pixel electrode, includes a gray voltage generator generating a plurality of gray voltages, an image signal modification assembly configured to receive a first image signal, a second image signal, and a third image signal for subsequent three frames and modify the second image signal based on the first image signal and the third image signal, and a data driver configured to provide a data voltage selected from the plurality of gray voltages to the pixel electrode corresponding to the modified signal in the image signal modification assembly. A longitudinal axis of the liquid crystal molecule is inclined at an angle with a longitudinal pixel electrode.

Claims

1. A liquid crystal display device comprising:

a first substrate;

a second substrate facing the first substrate;

a liquid crystal layer interposed between the first substrate and the second substrate;

a pixel electrode formed over the first substrate;

a common electrode formed over the first substrate with insulating from the pixel electrode, wherein a portion of the common electrode overlaps with the pixel electrode;

a gray voltage generator generating a plurality of gray voltages;

an image signal modification assembly configured to receive a first image signal, a second image signal, and a third image signal for subsequent three frames and modify the second image signal based on the first image signal and the third image signal; and

,

a data driver configured to provide a data voltage selected from the plurality of gray voltages to the pixel electrode corresponding to the modified signal in the image signal modification assembly;

wherein a longitudinal axis of the liquid crystal molecule is inclined at an angle with respect to a longitudinal axis of the pixel electrode.

2. The liquid crystal display device of claim 1, wherein the image signal modification assembly generates an initial modified image signal based on the first image signal and the second image signal, and then modifies the second image signal base on the initial modified image signal and the third image signal.

3. The liquid crystal display device of claim 1, wherein the angle is larger than 0 degree and less than or equal to 10 degrees.

4. A liquid crystal display device, comprising:

a first substrate and a second substrate facing with the first substrate;

a liquid crystal layer interposed between the first substrate and the second substrate;

a pixel electrode formed over the first substrate;

a common electrode formed over the second substrate with insulating from the pixel electrode, wherein a portion of the common electrode overlaps with the pixel electrode;

a gray voltage generator generating a plurality of gray voltages;

an image signal modification assembly configured to receive a first image signal, a second image signal, and a third image signal for subsequent three frames, and generate a first modified signal based on the first image signal and the second image signal and a second modified signal based on the first modified signal and the third image signal; and

a data driver configured to provide a data voltage selected from the plurality of gray voltages to the pixel electrode corresponding to the second modified signal in the image signal modification assembly,

wherein a longitudinal axis of the liquid crystal molecule is inclined at an angle with respect to a longitudinal axis of the pixel electrode.

5. The liquid crystal display device of claim 4, wherein the angle is larger than 0 degree and less than or equal to 10 degrees.

6. The liquid crystal display device of claim 4, wherein the pixel electrode has a bent portion.

7. The liquid crystal display device of claim 4, wherein the second modified signal is equal to a first correction constant when the first modified signal is less than a first value, and the third image signal is larger than a second value.

8. The liquid crystal display device of claim 4, wherein the second modified signal is equal to the sum of the first modified signal and a second correction constant when the first modified signal is less than a first value, and the third image signal is larger than a second value.

9. The liquid crystal display device of claim 7 or claim 8, wherein the second modified signal is equal to the first modified signal when the first modified signal is larger than the first value or the third image signal is less than the second value.

10. The liquid crystal display device of claim 9, wherein the modified first signal is larger than the second image signal when the first signal is less than the second image signal.

11. The liquid crystal display device of claim 4, wherein the image signal modification assembly comprises:

a first frame memory configured to output the second image signal and store the third image signal;

a second frame memory configured to output the first image signal and the store the second image signal;

a first modification unit configured to generate the first modified signal based on the second image signal from the first frame memory and the first image signal from the second frame memory; and

,

a second modification unit configured to generate the second modified signal based on the first modified signal from the first modification unit and the third image signal.

12. The liquid crystal display device of the claim 4, wherein a portion of the pixel electrode and a portion of the common electrode overlap to form a storage capacitor.

13. A liquid crystal display device comprising:

a first substrate and a second substrate facing with the first substrare;

a common electrode formed over either the first substrate or the second substrate;

a pixel electrode formed over the same substrate where the common electrode is formed;

a liquid crystal layer interposed between the first substrate and the second substrate;

a gray voltage generator generating a plurality of gray voltages;

an image signal modification assembly configured to receive a first image signal, a second image signal, and a third image signal for subsequent three frames, and generate a first modified signal based on the first image signal and the second image signal and a second modified signal based on the first modified signal and the third image signal; and

,

a data driver configured to provide a data voltage selected from the plurality of gray voltages to the pixel electrode corresponding to the second modified signal in the image signal modification assembly,

wherein a longitudinal axis of the liquid crystal molecule is inclined at an angle with a longitudinal axis of the pixel electrode.

14. The liquid crystal display device of claim 13, wherein the angle is larger than 0 degree and less than or equal to 10 degrees.

15. The liquid crystal display device of claim 13, wherein the pixel electrode and the common electrode have transverse parts and longitudinal parts, wherein the longitudinal part has a bent shape.

16. The liquid crystal display device of claim 13, wherein the longitudinal parts of the pixel electrode are disposed alternately with and in parallel with the longitudinal parts of the common electrode.

17. A method for driving a liquid crystal display device including a pixel electrode and a common electrode formed over a same substrate, a plurality of pixel defined by a gate line and a data line, a liquid crystal molecule aligned between the pixel electrode and the common electrode, wherein the liquid crystal molecule is inclined at a range of angle larger than 0 degree and less than or equal to 10 degrees with a longitudinal direction of the pixel electrode comprising:

generating a plurality of gray voltages;

receiving a first image signal, a second image signal, and a third image signal for subsequent three frames;

generating a first modified signal based on the first image signal and the second image signal;

generating a second modified signal based on the first modified signal and the third image signal;

selecting a data voltage from the plurality of gray voltages corresponding to the second modified signal; and

,

providing the data voltage to the pixel.

18. The method of claim 17, wherein generating the second modified signal further comprises:

comparing the first modified signal with a first value;

comparing the third image signal with a second value; and

,

generating the second modified signal based on the comparison results.

19. The method of claim 18, wherein the second modified signal has a first correction constant when the first modified signal is less than the first value and the third image signal is larger than the second value.

20. The method of claim 19, wherein the second modified signal is equal to the first modified signal when the first modified signal is equal or larger than the first value, or the third image signal is equal or less than the second value.

21. The method of claim 18, wherein the second modified signal is equal to the sum of the first modified signal and a second correction constant when the first modified signal is less than the first value, or the third image signal is larger than the second value.

22. The method of claim 21 or claim 21, wherein the first modified signal is equal or larger than the second image signal when the first image signal is less than the second image signal.