DISPLAY DEVICE

• US 20070120785A1
• Filed: 11/28/2006
• Published: 05/31/2007
• Est. Priority Date: 11/30/2005
• Status: Active Grant

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: KIMURA, Hajime
• Granted Patent: US 7,692,610 B2
• Time in Patent Office: Days
• US Class Current: 345/82
• CPC Class Codes: G09G 2300/0465 Improved aperture ratio, e.g. by size reduction of the pixel circuit, e.g. for improving the pixel density or the maximum displayable luminance or brightness
• CPC Class Codes: G09G 2300/0819 used for counteracting undesired variations, e.g. feedback or autozeroing
• 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 2300/0861 with additional control of the display period without amending the charge stored in a pixel memory, e.g. by means of additional select electrodes
• CPC Class Codes: G09G 2310/0251 Precharge or discharge of pixel before applying new pixel voltage
• CPC Class Codes: G09G 2320/043 Preventing or counteracting the effects of ageing
• CPC Class Codes: G09G 2330/04 Display protection
• CPC Class Codes: G09G 3/3233 with pixel circuitry controlling the current through the light-emitting element
• CPC Class Codes: G09G 3/325 the data current flowing through the driving transistor during a setting phase, e.g. by using a switch for connecting the driving transistor to the data driver
• CPC Class Codes: H10K 59/12 Active-matrix OLED [AMOLED] displays

Abstract

To provide a high-performance and highly reliable display device with a high aperture ratio, including light-emitting elements, and a manufacturing method thereof, and a technique for manufacturing such a display device at a low cost with high productivity. A compensating circuit, a light-emitting element, a switch, and a transistor are included, in which one terminal of the switch is electrically connected to the compensating circuit, a gate of the transistor is electrically connected to the compensating circuit, one of a source and a drain of the transistor is electrically connected to a first electrode of the light-emitting element, the other of the source and the drain of the transistor is maintained at a certain potential, and a second electrode of the light-emitting element and the other terminal of the switch are electrically connected to the same wire.

Claims

1. A display device comprising:

a compensating circuit;

a light-emitting element;

a switch; and

a transistor,

wherein one terminal of the switch is electrically connected to the compensating circuit,

wherein a gate of the transistor is electrically connected to the compensating circuit and one of a source and a drain of the transistor is electrically connected to a first electrode of the light-emitting element, and

wherein a second electrode of the light-emitting element and the other terminal of the switch are electrically connected to a same wire.

2. The display device according to claim 1, wherein the switch is a transistor.

3. The display device according to claim 1, wherein the wire is maintained at a fixed potential.

4. The display device according to claim 2, wherein the transistors are thin film transistors.

5. The display device according to claim 1, wherein the other of the source and the drain of the transistor is electrically connected to a second wire.

6. A display device comprising:

a compensating circuit;

a light-emitting element;

a first switch;

a second switch;

a transistor; and

a controlling circuit,

wherein one terminal of the first switch is electrically connected to the compensating circuit,

wherein one terminal of the second switch is electrically connected to the compensating circuit, and the other terminal of the second switch is electrically connected to a first wire,

wherein a gate of the transistor is electrically connected to the compensating circuit, one of a source and a drain of the transistor is electrically connected to the light-emitting element, and the other of the source and the drain of the transistor is electrically connected to the controlling circuit, and

wherein a second electrode of the light-emitting element and the other terminal of the first switch are electrically connected to a same second wire.

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

8. The display device according to claim 6, wherein the second wire is maintained at a fixed potential.

9. The display device according to claim 7, wherein the transistors are thin film transistors.

10. A display device comprising:

a light-emitting element;

a first switch;

a second switch;

a transistor;

a first capacitor; and

a second capacitor,

wherein one terminal of the first switch is electrically connected to a first electrode of the second capacitor,

wherein a second electrode of the second capacitor is electrically connected to one terminal of the second switch and a first electrode of the first capacitor,

wherein a second electrode of the first capacitor is electrically connected to a first wire,

wherein a gate of the transistor is electrically connected to the first electrode of the second capacitor, one of a source and a drain of the transistor is electrically connected to a first electrode of the light-emitting element, and the other of the source and the drain of the transistor is electrically connected to the other terminal of the second switch, and

wherein a second electrode of the light-emitting element and the other terminal of the first switch are electrically connected to a same second wire.

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

12. The display device according to claim 10, wherein the second wire is maintained at a fixed potential.

13. The display device according to claim 11, wherein the transistors are thin film transistors.

14. The display device according to claim 10, wherein the other of the source and the drain of the transistor is electrically connected to a third wire.

15. A display device comprising:

a light-emitting element;

a first switch;

a second switch;

a third switch;

a fourth switch;

a transistor;

a first capacitor; and

a second capacitor,

wherein one terminal of the first switch is electrically connected to a first electrode of the second capacitor, and a second electrode of the second capacitor is electrically connected to one terminal of the second switch and a first electrode of the first capacitor,

wherein a second electrode of the first capacitor is electrically connected to a first wire,

wherein one terminal of the third switch is electrically connected to the second electrode of the second capacitor, and the other terminal of the third switch is electrically connected to a second wire,

wherein a gate of the transistor is electrically connected to the first electrode of the second capacitor, one of a source and a drain of the transistor is electrically connected to a first electrode of the light-emitting element, and the other of the source and the drain of the transistor is electrically connected to the other terminal of the second switch and one terminal of the fourth switch, and

wherein a second electrode of the light-emitting element and the other terminal of the first switch are electrically connected to a same third wire.

16. The display device according to claim 15, wherein the first switch, the second switch, the third switch, and the fourth switch are transistors.

17. The display device according to claim 15, wherein the third wire is maintained at a fixed potential.

18. The display device according to claim 16, wherein the transistors are thin film transistors.

19. The display device according to claim 15, wherein the other terminal of the fourth switch is electrically connected to a fourth wire.