LIQUID CRYSTAL DISPLAY DEVICE

• US 20080284929A1
• Filed: 05/05/2008
• Published: 11/20/2008
• Est. Priority Date: 05/18/2007
• Status: Active Grant

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: KIMURA, Hajime
• Granted Patent: US 8,253,911 B2
• Time in Patent Office: Days
• US Class Current: 349/38
• CPC Class Codes: G02F 1/134345 Subdivided pixels, e.g. for grey scale or redundancy
• CPC Class Codes: G02F 1/136213 Storage capacitors associated with the pixel electrode
• CPC Class Codes: G02F 1/136227 Through-hole connection of the pixel electrode to the active element through an insulation layer
• CPC Class Codes: G02F 1/13624 having more than one switching element per pixel
• CPC Class Codes: G02F 1/136286 Wiring, e.g. gate line, drain line
• CPC Class Codes: G02F 1/136295 Materials; Compositions; Manufacture processes
• CPC Class Codes: G02F 1/1368 in which the switching element is a three-electrode device G02F1/136277 takes precedence
• CPC Class Codes: G09G 2300/0443 with several sub-pixels for the same colour in a pixel, not specifically used to display gradations G09G3/364 takes precedence
• CPC Class Codes: G09G 2300/0447 for multi-domain technique to improve the viewing angle in a liquid crystal display, such as multi-vertical alignment [MVA]
• CPC Class Codes: G09G 2300/0809 Several active elements per pixel in active matrix panels
• CPC Class Codes: G09G 2300/0842 forming a memory circuit, e.g. a dynamic memory with one capacitor
• CPC Class Codes: G09G 2300/0852 being a dynamic memory with more than one capacitor
• CPC Class Codes: G09G 2310/0262 The addressing of the pixel, in a display other than an active matrix LCD, involving the control of two or more scan electrodes or two or more data electrodes, e.g. pixel voltage dependent on signals of two data electrodes
• CPC Class Codes: G09G 2320/0252 Improving the response speed
• CPC Class Codes: G09G 2320/0261 in the context of movement of objects on the screen or movement of the observer relative to the screen
• CPC Class Codes: G09G 2320/028 by changing the viewing angle properties, e.g. widening the viewing angle, adapting the viewing angle to the view direction
• CPC Class Codes: G09G 2320/10 Special adaptations of display systems for operation with variable images
• CPC Class Codes: G09G 2320/106 Determination of movement vectors or equivalent parameters within the image
• CPC Class Codes: G09G 2330/021 Power management, e.g. power saving
• CPC Class Codes: G09G 2340/0435 Change or adaptation of the frame rate of the video stream
• 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 3/2022 : using sub-frames
• CPC Class Codes: G09G 3/3233 : with pixel circuitry controlling the current through the light-emitting element
• CPC Class Codes: G09G 3/3648 : using an active matrix G09G3/367 - G09G3/3696 take precedence
• CPC Class Codes: G09G 3/3659 : the addressing of the pixel involving the control of two or more scan electrodes or two or more data electrodes, e.g. pixel voltage dependant on signal of two data electrodes
• CPC Class Codes: H01L 27/12 : the substrate being other than a semiconductor body, e.g. an insulating body

Abstract

To improve viewing angle characteristics by varying voltage which is applied between liquid crystal elements. A liquid crystal display device in which one pixel is provided with three or more liquid crystal elements and the level of voltage which is applied is varied between the liquid crystal elements is varied. In order to vary the level of the voltage which is applied between the liquid crystal elements, an element which divides the applied voltage is provided. In order to vary the level of the applied voltage, a capacitor, a resistor, a transistor, or the like is used. Viewing angle characteristics can be improved by varying the level of the voltage which is applied between the liquid crystal elements.

Claims

1. A liquid crystal display device comprising:

a pixel comprising;

a first switch and a second switch;

a first liquid crystal element, a second liquid crystal element, and a third liquid crystal element;

a first capacitor, and a second capacitor;

a first wiring electrically connected to one of electrodes of the first liquid crystal element and one of terminals of the first capacitor through the first switch; and

a second wiring electrically connected to one of electrodes of the second liquid crystal element and one of terminals of the second capacitor through the second switch,

wherein the other of the terminals of the first capacitor is electrically connected to the other of the terminals of the second capacitor and one of electrodes of the third liquid crystal element, and

wherein the other of the electrodes of the first liquid crystal element, the other of the electrodes of the second liquid crystal element, and the other of the electrodes of the third liquid crystal element are electrically connected to each other.

10. The liquid crystal display device according to claim 1, wherein the first switch and the second switch are transistors.

19. The liquid crystal display device according to claim 1,

wherein a storage capacitor is electrically connected to each of the one of the terminals of the first liquid crystal element, the one of the terminals of the second liquid crystal element, and the one of the terminals of the third liquid crystal element;

and

wherein the storage capacitor is electrically connected to a wiring having a constant potential.

2. A liquid crystal display device comprising:

a pixel comprising;

a first switch, and a second switch;

a first liquid crystal element, a second liquid crystal element, and a third liquid crystal element;

a first capacitor, a second capacitor, and a third capacitor;

a first wiring electrically connected to one of electrodes of the first liquid crystal element and one of terminals of the first capacitor through the first switch; and

a second wiring electrically connected to one of electrodes of the second liquid crystal element and one of terminals of the second capacitor through the second switch,

wherein the other of the terminals of the first capacitor is electrically connected to the other of the terminals of the second capacitor and one of terminals of the third capacitor,

wherein the other of the terminals of the third capacitor is electrically connected to one of electrodes of the third liquid crystal element, and

wherein the other of the electrodes of the first liquid crystal element, the other of the electrodes of the second liquid crystal element, and the other of the electrodes of the third liquid crystal element are electrically connected to each other.

11. The liquid crystal display device according to claim 2, wherein the first switch and the second switch are transistors.

20. The liquid crystal display device according to claim 2,

wherein a storage capacitor is electrically connected to each of the one of the terminals of the first liquid crystal element, the one of the terminals of the second liquid crystal element, and the one of the terminals of the third liquid crystal element;

and

wherein the storage capacitor is electrically connected to a wiring having a constant potential.

3. A liquid crystal display device comprising:

a pixel comprising;

a first switch, and a second switch;

a transistor;

a first liquid crystal element, a second liquid crystal element, and a third liquid crystal element;

a first capacitor, a second capacitor, and a third capacitor;

a first wiring electrically connected to one of electrodes of the first liquid crystal element and one of terminals of the first capacitor through the first switch;

wherein the first wiring is electrically connected to one of electrodes of the third liquid crystal element, the other of the terminals of the first capacitor, and one of terminals of the second capacitor through the transistor;

a second wiring is electrically connected to one of electrodes of the second liquid crystal element and the other of the terminals of the second capacitor through the second switch,

wherein one of terminals of the third capacitor is electrically connected to the other of the electrodes of the third liquid crystal element, and

wherein the other of the electrodes of the first liquid crystal element, the other of the electrodes of the second liquid crystal element, and the other of the electrodes of the third liquid crystal element are electrically connected to each other.

12. The liquid crystal display device according to claim 3, wherein the first switch and the second switch are transistors.

21. The liquid crystal display device according to claim 3,

wherein a storage capacitor is electrically connected to each of the one of the terminals of the first liquid crystal element, the one of the terminals of the second liquid crystal element, and the one of the terminals of the third liquid crystal element;

and

wherein the storage capacitor is electrically connected to a wiring having a constant potential.

4. A liquid crystal display device comprising:

a pixel comprising;

a first switch, and a second switch;

a first liquid crystal element, a second liquid crystal element, and a third liquid crystal element;

a first resistor, and a second resistor;

a first wiring electrically connected to one of electrodes of the first liquid crystal element and one of terminals of the first resistor through the first switch; and

a second wiring electrically connected to one of electrodes of the second liquid crystal element and one of terminals of the second resistor through the second switch,

wherein the other of the terminals of the first resistor is electrically connected to the other of the terminals of the second resistor and one of electrodes of the third liquid crystal element; and

wherein the other of the electrodes of the first liquid crystal element, the other of the electrodes of the second liquid crystal element, and the other of the electrodes of the third liquid crystal element are electrically connected to each other.

13. The liquid crystal display device according to claim 4, wherein the first switch and the second switch are transistors.

22. The liquid crystal display device according to claim 4,

wherein a storage capacitor is electrically connected to each of the one of the terminals of the first liquid crystal element, the one of the terminals of the second liquid crystal element, and the one of the terminals of the third liquid crystal element;

and

wherein the storage capacitor is electrically connected to a wiring having a constant potential.

5. A liquid crystal display device comprising:

a pixel comprising;

a first switch, and a second switch;

a first liquid crystal element, a second liquid crystal element, and a third liquid crystal element;

a first resistor, a second resistor, and a third resistor;

a first wiring electrically connected to one of electrodes of the first liquid crystal element and one of terminals of the first resistor through the first switch; and

a second wiring electrically connected to one of electrodes of the second liquid crystal element and one of terminals of the second resistor through the second switch,

wherein the other of the terminals of the first resistor is electrically connected to the other of the terminals of the second resistor and one of terminals of the third resistor;

wherein the other of the terminals of the third resistor is electrically connected to one of electrodes of the third liquid crystal element, and

wherein the other of the electrodes of the first liquid crystal element, the other of the electrodes of the second liquid crystal element, and the other of the electrodes of the third liquid crystal element are electrically connected to each other.

14. The liquid crystal display device according to claim 5, wherein the first switch and the second switch are transistors.

23. The liquid crystal display device according to claim 5,

wherein a storage capacitor is electrically connected to each of the one of the terminals of the first liquid crystal element, the one of the terminals of the second liquid crystal element, and the one of the terminals of the third liquid crystal element;

and

wherein the storage capacitor is electrically connected to a wiring having a constant potential.

6. A liquid crystal display device comprising:

a pixel comprising;

a first switch, and a second switch;

a transistor;

a first liquid crystal element, a second liquid crystal element, and a third liquid crystal element;

a first resistor, a second resistor, and a third resistor;

a first wiring electrically connected to one of electrodes of the first liquid crystal element and one of terminals of the first resistor through the first switch;

wherein the first wiring is electrically connected to one of electrodes of the third liquid crystal element, the other of the terminals of the first resistor, and one of terminals of the second resistor through the transistor,

a second wiring electrically connected to one of electrodes of the second liquid crystal element and the other of the terminals of the second resistor through the second switch,

wherein one of terminals of the third resistor is electrically connected to the other of the electrodes of the third liquid crystal element, and

wherein the other of the electrodes of the first liquid crystal element, the other of the electrodes of the second liquid crystal element, and the other of the electrodes of the third liquid crystal element are electrically connected to each other.

15. The liquid crystal display device according to claim 6, wherein the first switch and the second switch are transistors.

24. The liquid crystal display device according to claim 6,

wherein a storage capacitor is electrically connected to each of the one of the terminals of the first liquid crystal element, the one of the terminals of the second liquid crystal element, and the one of the terminals of the third liquid crystal element;

and

wherein the storage capacitor is electrically connected to a wiring having a constant potential.

7. A liquid crystal display device comprising:

a pixel comprising;

a first switch, and a second switch;

a first liquid crystal element, a second liquid crystal element, and a third liquid crystal element;

a first transistor, and a second transistor;

a first wiring is electrically connected to one of electrodes of the first liquid crystal element and one of terminals of the first transistor through the first switch; and

a second wiring is electrically connected to one of electrodes of the second liquid crystal element and one of terminals of the second transistor through the second switch,

wherein the other of the terminals of the first transistor is electrically connected to the other of the terminals of the second transistor and one of electrodes of the third liquid crystal element, and

wherein the other of the electrodes of the first liquid crystal element, the other of the electrodes of the second liquid crystal element, and the other of the electrodes of the third liquid crystal element are electrically connected to each other.

16. The liquid crystal display device according to claim 7, wherein the first switch and the second switch are transistors.

25. The liquid crystal display device according to claim 7,

wherein a storage capacitor is electrically connected to each of the one of the terminals of the first liquid crystal element, the one of the terminals of the second liquid crystal element, and the one of the terminals of the third liquid crystal element;

and

wherein the storage capacitor is electrically connected to a wiring having a constant potential.

8. A liquid crystal display device comprising:

a pixel comprising;

a first switch, and a second switch;

a first liquid crystal element, a second liquid crystal element, and a third liquid crystal element;

a first transistor, a second transistor, and a third transistor;

a first wiring electrically connected to one of electrodes of the first liquid crystal element and one of terminals of the first transistor through the first switch, and

a second wiring electrically connected to one of electrodes of the second liquid crystal element and one of terminals of the second transistor through the second switch,

wherein the other of the terminals of the first transistor is electrically connected to the other of the terminals of the second transistor and one of terminals of the third transistor;

wherein the other of the terminals of the third transistor is electrically connected to one of electrodes of the third liquid crystal element; and

wherein the other of the electrodes of the first liquid crystal element, the other of the electrodes of the second liquid crystal element, and the other of the electrodes of the third liquid crystal element are electrically connected to each other.

17. The liquid crystal display device according to claim 8, wherein the first switch and the second switch are transistors.

26. The liquid crystal display device according to claim 8,

wherein a storage capacitor is electrically connected to each of the one of the terminals of the first liquid crystal element, the one of the terminals of the second liquid crystal element, and the one of the terminals of the third liquid crystal element;

and

wherein the storage capacitor is electrically connected to a wiring having a constant potential.

9. A liquid crystal display device comprising:

a pixel comprising;

a first switch, and a second switch;

a transistor;

a first liquid crystal element, a second liquid crystal element, and a third liquid crystal element;

a first transistor, a second transistor, and a third transistor;

a first wiring electrically connected to one of electrodes of the first liquid crystal element and one of terminals of the first transistor through the first switch;

wherein the first wiring is electrically connected to one of electrodes of the third liquid crystal element, the other of the terminals of the first transistor, and one of terminals of the second transistor through the transistor,

a second wiring is electrically connected to one of electrodes of the second liquid crystal element and the other of the terminals of the second transistor through the second switch,

wherein one of terminals of the third transistor is electrically connected to the other of the electrodes of the third liquid crystal element, and

wherein the other of the electrodes of the first liquid crystal element, the other of the electrodes of the second liquid crystal element, and the other of the electrodes of the third liquid crystal element are electrically connected to each other.

18. The liquid crystal display device according to claim 9, wherein the first switch and the second switch are transistors.

27. The liquid crystal display device according to claim 9,

wherein a storage capacitor is electrically connected to each of the one of the terminals of the first liquid crystal element, the one of the terminals of the second liquid crystal element, and the one of the terminals of the third liquid crystal element;

and

wherein the storage capacitor is electrically connected to a wiring having a constant potential.