Display device and method of manufacturing the same

• US 20060082568A1
• Filed: 12/06/2005
• Published: 04/20/2006
• Est. Priority Date: 06/06/2000
• Status: Active Grant

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Kimura, Hajime, Arai, Yasuyuki, Yamazaki, Shunpei
• Granted Patent: US 7,830,370 B2
• Time in Patent Office: Days
• US Class Current: 345/207
• CPC Class Codes: G09G 2300/0426 Layout of electrodes and connections
• CPC Class Codes: G09G 2300/0842 forming a memory circuit, e.g. a dynamic memory with one capacitor
• CPC Class Codes: G09G 2320/0276 for the purpose of adaptation to the characteristics of a display device, i.e. gamma correction
• CPC Class Codes: G09G 2320/043 Preventing or counteracting the effects of ageing
• CPC Class Codes: G09G 2320/0626 for control of overall brightness
• CPC Class Codes: G09G 2360/144 the light being ambient light
• CPC Class Codes: G09G 3/2018 by time modulation using two or more time intervals
• CPC Class Codes: G09G 3/2022 using sub-frames
• CPC Class Codes: G09G 3/30 using electroluminescent panels
• 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

Abstract

There is provided a display device capable of automatically controlling a luminance in response to a brightness of a surrounding. The display device has a gamma correction circuit for converting an image signal voltage into a drive voltage for gray scale display and a photosensor for controlling an input and output voltage characteristic of the gamma correction circuit in response to the brightness of the surrounding. In this case, the gamma correction circuit for converting the image signal voltage into the driver voltage for gray scale display is formed on a first substrate. The photosensor for controlling the input and output voltage characteristic of the gamma correction circuit in response to the brightness of the surrounding is formed on a second substrate. The second substrate is fixed to the first substrate.

Claims

1. -35. (canceled)

36. A method of manufacturing a display device comprising:

forming a pixel portion using a thin film transistor over a first substrate;

forming a photosensor over a second substrate; and

fixing the second substrate to said first substrate after forming the pixel portion and the photo sensor.

37. A method of manufacturing a display device according to claim 36, wherein at least a pixel electrode, a liquid crystal layer, and a counter electrode are formed in the pixel portion.

38. A method of manufacturing a display device according to claim 36, wherein at least a pixel electrode and a light emitting layer are formed in the pixel portion.

39. A method of manufacturing a display device according to claim 36, wherein the photosensor has a photoelectric conversion layer comprising amorphous silicon.

40. A method of manufacturing a display device according to claim 36, wherein the display device is incorporated into an electronic equipment selected from the group consisting of a video camera, a digital camera, a projector, a head-mounted display, a car navigation system, a car stereo, a personal computer, a portable telephone and a portable information terminal.

41. A method of manufacturing a display device according to claim 36, wherein the first substrate and the second substrate are fixed by at least one of a resin having a conductive particle and a conductive material.

42. A method of manufacturing a display device according to claim 36, wherein the photosensor is electrically connected to a circuit over the first substrate.

43. A method of manufacturing a display device according to claim 36, further comprising:

detecting a brightness of a surrounding by the photosensor;

changing an amplitude of an image signal based on an output of the photosensor; and

controlling a luminance of a pixel in the pixel portion based on the changed image signal.

44. A method of manufacturing a display device comprising:

forming a pixel portion, a driver circuit for driving the pixel portion, and a control circuit for controlling a brightness of the pixel portion, using a thin film transistor, over a first substrate;

forming a photosensor over a second substrate; and

fixing the second substrate to the first substrate to electrically connect the control circuit with the photosensor after forming the pixel portion, the driver circuit, the control circuit and the photosensor.

45. A method of manufacturing a display device according to claim 44, wherein at least a pixel electrode, a liquid crystal layer, and a counter electrode are formed in the pixel portion.

46. A method of manufacturing a display device according to claim 44, wherein at least a pixel electrode and a light emitting layer are formed in the pixel portion.

47. A method of manufacturing a display device according to claim 44, wherein the photosensor has a photoelectric conversion layer comprising amorphous silicon.

48. A method of manufacturing a display device according to claim 44, wherein the display device is incorporated into an electronic equipment selected from the group consisting of a video camera, a digital camera, a projector, a head-mounted display, a car navigation system, a car stereo, a personal computer, a portable telephone and a portable information terminal.

49. A method of manufacturing a display device according to claim 44, wherein the first substrate and the second substrate are fixed by at least one of a resin having a conductive particle and a conductive material.

50. A method of manufacturing a display device according to claim 44, further comprising:

detecting a brightness of a surrounding by the photosensor;

changing an amplitude of an image signal based on an output of the photosensor; and

controlling the brightness of the pixel portion based on the changed image signal.