Liquid crystal display device and driving method thereof, and electronic device with the liquid crystal display device

• US 20080158138A1
• Filed: 12/26/2007
• Published: 07/03/2008
• Est. Priority Date: 12/27/2006
• Status: Abandoned Application

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Umezaki, Atsushi, Yamazaki, Shunpei
• Application Number:
  US12/003,428
• Publication Number:
  US 20080158138A1
• Time in Patent Office: Days
• US Class Current: 345/102
• CPC Class Codes: G02F 1/13318 Circuits comprising a photodetector
• CPC Class Codes: G09G 2320/0633 by amplitude modulation of the brightness of the illumination source
• CPC Class Codes: G09G 2330/021 Power management, e.g. power saving
• CPC Class Codes: G09G 2360/144 the light being ambient light
• CPC Class Codes: G09G 3/3406 Control of illumination source illumination devices structurally associated with liquid crystal cells G02F1/1336

Abstract

It is an object of the present invention to provide a small-size and highly precise liquid crystal display device which has a function of adjusting luminance by using an optical sensor. Another object of the present invention is to provide a liquid crystal display with high image quality and low power consumption by function of adjusting luminance. A photoelectric conversion device is provided between a liquid crystal display panel and a backlight device. The photoelectric conversion device (also referred to as a photo IC) has a sensor for detecting light and the driver portion for the driving the sensor. The intensity of light from the backlight device can be controlled by detecting the external light which enters the liquid crystal panel and affects the display with the sensor, and by feeding back the data to the backlight device.

Claims

1. A liquid crystal display device comprising:

a photoelectric conversion device;

a liquid crystal panel provided with a pixel portion and a peripheral portion of the pixel portion; and

a backlight device,

wherein the photoelectric conversion device is provided between the backlight device and the liquid crystal panel.

2. The liquid crystal display device according to claim 1, wherein the photoelectric conversion device comprises a sensor and a driver portion, and

wherein the sensor is provided between the backlight device and the pixel portion.

3. The liquid crystal display device according to claim 2, wherein the driver portion is provided between the backlight device and the peripheral portion of the pixel portion.

4. The liquid crystal display device according to claim 1, further a circuit on the peripheral portion of the pixel portion, the circuit being formed over a single crystalline substrate.

5. The liquid crystal display device according to claim 1, further comprising a circuit on the peripheral portion of the pixel portion, the circuit being formed over a same substrate as the pixel portion.

15. The liquid crystal display device according to claim 1, wherein the liquid crystal panel is an active matrix type device.

16. An electronic device comprising the liquid crystal display device according to claim 1.

6. A liquid crystal display device comprising:

a photoelectric conversion device comprising a sensor and a driver portion;

a liquid crystal panel provided with a pixel portion; and

a backlight device,

wherein the pixel portion includes a light-transmitting region and a light-shielding region, and

wherein the sensor is provided between the backlight device and the light-transmitting region.

7. The liquid crystal display device according to claim 6, wherein the driver portion is provided between the backlight device and the light-shielding region.

8. The liquid crystal display device according to claim 6, further comprising a wiring provided in the light-shielding region.

9. The liquid crystal display device according to claim 6, further comprising a transistor provided in the light-shielding region.

10. The liquid crystal display device according to claim 6, further comprising a black matrix provided in the light-shielding region.

17. The liquid crystal display device according to claim 6, wherein the liquid crystal panel is an active matrix type device.

18. An electronic device comprising the liquid crystal display device according to claim 6.

11. A liquid crystal display device comprising:

a photoelectric conversion device comprising a sensor and a driver portion;

a liquid crystal panel provided with a pixel portion; and

a backlight device,

wherein the pixel portion includes a light-transmitting region and a reflective region, and

wherein the sensor is provided between the backlight device and the light-transmitting region.

12. The liquid crystal display device according to claim 11, wherein the driver portion is provided between the backlight device and the reflective region.

13. The liquid crystal display device according to claim 11, wherein a first pixel electrode having a light-transmitting property is provided in the light-transmitting region, and wherein a second pixel electrode having a reflective property is provided in the reflective region.

19. The liquid crystal display device according to claim 11, wherein the liquid crystal panel is an active matrix type device.

20. An electronic device comprising the liquid crystal display device according to claim 11.

14. A liquid crystal display device comprising:

a liquid crystal panel;

a control circuit operationally connected to the liquid crystal panel;

a backlight device operationally connected to the control circuit; and

a photoelectric conversion device operationally connected to the control circuit and being capable of detecting external light passing through the liquid crystal panel,

wherein the photoelectric conversion device is provided between the backlight device and the liquid crystal panel.

21. The liquid crystal display device according to claim 14, wherein the control circuit is included in the liquid crystal panel.

22. The liquid crystal display device according to claim 14, wherein the liquid crystal panel is an active matrix type device.

23. An electronic device comprising the liquid crystal display device according to claim 14.

24. A driving method of a liquid crystal display device which includes a photoelectric conversion device, a liquid crystal panel and a backlight device, the method comprising the steps of:

detecting an external light by the photoelectric conversion device, the external light entering into the liquid crystal display device through the liquid crystal panel; and

controlling a luminance of the backlight device based on the external light detected by the photoelectric conversion device,

wherein the photoelectric conversion device is provided between the backlight device and the liquid crystal panel.

25. A driving method of a liquid crystal display device according to claim 24, the backlight device is turned off during the detecting step.