MOS sensor and drive method thereof

• US 7,224,391 B2
• Filed: 05/25/2001
• Issued: 05/29/2007
• Est. Priority Date: 05/26/2000
• Status: Expired due to Fees

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Kimura, Hajime
• Primary Examiner(s): Ye; Lin
• Application Number:
  US09/864,280
• Publication Number:
  US 20020012057A1
• Time in Patent Office: 2,195 Days
• Field of Search: 348/308, 348/301, 348/302, 348/303, 348/304, 348/307, 348/241, 348/362, 348/363, 348/364, 348/294, 348/310, 257/208, 257/292, 257/448, 235/462.01
• US Class Current: 348/310
• CPC Class Codes: H04N 2101/00 Still video cameras
• CPC Class Codes: H04N 23/30 for generating image signals from X-rays
• CPC Class Codes: H04N 25/58 involving two or more exposures
• CPC Class Codes: H04N 25/76 Addressed sensors, e.g. MOS or CMOS sensors
• CPC Class Codes: H04N 5/32 Transforming X-rays cameras or camera modules for generating image signals from X-rays H04N23/30; circuitry of SSIS for transforming X-rays into image signals H04N25/30

Abstract

To provide a drive method for finding out an optimum storage period quickly.

In the method for driving the MOS sensor having a plurality of pixels, after all the plurality of pixels are simultaneously reset, signals are then sequentially outputted from said plurality of pixels. The period from the reset time to the time just before said plurality of pixels output saturated signals is termed as the storage period.

Claims

1. A driving method of a MOS sensor having a plurality of pixels in an image pick up unit, each of said pixels comprising:

a reset transistor;

a photoelectric conversion element having a first terminal connected to one of source or drain terminals of said reset transistors, and a second terminal connected to a photoelectric conversion clement side power source line;

a reset signal line connected to a gate terminal of said reset transistor;

a signal amplifier circuit having an input terminal connected to said one of the source or drain terminals of said reset transistor;

a reset side power source line connected to other one of the source or drain terminals of said reset transistor;

said method comprising the steps of;

imaging a first object on trial, comprising the steps of;

resetting said plurality of pixels at a same time; and

sequentially selecting at least a part of said plurality of pixels to output signals of the selected pixels;

determining a storage period in accordance with a period from the time of said resetting to a time when the signal of the selected pixels saturate; and

imaging a second object ordinarily, comprising the steps of;

resetting said plurality of pixels sequentially; and

selecting said plurality of pixels sequentially after said storage period has passed since resetting said plurality of pixels.

2. The method according to claim 1 wherein a value of said storage period is set by irradiating said image pick up unit with light having a highest intensity among lights which have been reflected by an object to enter said image pick up unit.

3. The method according to claim 1 wherein the signals are outputted exclusively from those of the plurality of pixels of said image pick up unit that belong to a limited area.

4. The method according to claim 1 wherein the image of an object is picked up by using said storage period.

5. A scanner using said MOS sensor according to claim 4.

6. A mobile information terminal using said MOS sensor according to claim 4.

7. A fingerprint reading device using said MOS sensor according to claim 4.

8. An electric apparatus having said MOS sensor according to claim 4 wherein said electronic apparatus is selected from the group consisting of a digital still camera, a mobile phone, a mobile game device, and a personal computer.

9. A scanner using said MOS sensor according to claim 1.

10. A mobile information terminal using said MOS sensor according to claim 1.

11. A fingerprint reading device using said MOS sensor according to claim 1.

12. An electric apparatus having said MOS sensor according to claim 1 wherein said electronic apparatus is selected from the group consisting of a digital still camera, a mobile phone, a mobile game device, and a personal computer.

13. The method according to claim 1 wherein the first object is second object.

14. A driving method of a MOS sensor having a plurality of pixels in an image pick up unit, each of said pixels comprising:

a reset transistor;

a photoelectric conversion element having a first terminal connected to one of source or drain terminals of said reset transistor, and a second terminal connected to a photoelectric conversion element side power source line;

a reset signal line connected to a gate terminal of said reset transistor;

a signal amplifier circuit having an input terminal connected to said one of the source or drain terminals of said reset transistor;

a reset side power source line connected to other one of the source or drain terminals of said reset transistor;

said method comprising the steps of;

imaging a first object on trial, comprising the steps of;

resetting said plurality of pixels at a same time; and

sequentially selecting a part of the plurality of pixels to output signals of the selected pixels;

determining a storage period in accordance with a period from the time of said resetting to a time when one of the signals of the selected pixels saturates; and

imaging a second object ordinarily, comprising the steps of;

resetting said plurality of pixels sequentially; and

selecting said plurality of pixels sequentially after said storage period has passed since resetting said plurality of pixels;

wherein said one of the signals has a largest signal amplitude among the signals of the selected pixels.

15. The method according to claim 14 wherein a value of said storage period is set by irradiating said image pick up unit with light having a highest intensity among lights which have been reflected by an object to enter said image pick up unit.

16. The method according to claim 14 wherein the signals are outputted exclusively from those of the plurality of pixels of said image pick up unit that belong to a limited area.

17. A scanner using said MOS sensor according to claim 16.

18. A mobile information terminal using said MOS sensor according to claim 16.

19. A fingerprint reading device using said MOS sensor according to claim 16.

20. An electric apparatus having said MOS sensor according to claim 16 wherein said electronic apparatus is selected from the group consisting of a digital still camera, a mobile phone, a mobile game device, and a personal computer.

21. The method according to claim 14 wherein the image of an object is picked up by using said storage period.

22. A scanner using said MOS sensor according to claim 14.

23. A mobile information terminal using said MOS sensor according to claim 14.

24. A fingerprint reading device using said MOS sensor according to claim 14.

25. An electric apparatus having said MOS sensor according to claim 14 wherein said electronic apparatus is selected from the group consisting of a digital still camera, a mobile phone, a mobile game device, and a personal computer.

26. The method according to claim 14 wherein the first object is second object.

27. A driving method of a MOS sensor having a plurality of pixels in an image pick up unit, each of said pixels comprising:

a reset transistor;

a photoelectric conversion element having a first terminal connected to one of source or drain terminals of said reset transistor, and a second terminal connected to a photoelectric conversion element side power source line;

a reset signal line connected to a gate terminal of said reset transistor;

a signal amplifier circuit having an input terminal connected to said one of the source or drain terminals of said reset transistor;

a reset side power source line connected to other one of the source or drain terminals of said reset transistor;

said method comprising the steps of;

imaging a first object on trial, comprising the steps of;

resetting said plurality of pixels at a same time; and

sequentially selecting the plurality of pixels to output signals of the selected pixels;

determining a storage period in accordance with a period from the time of said resetting to a time when the photoelectric conversion element(s) of the selected pixels saturates; and

imaging a second object ordinarily, comprising the steps of;

resetting said plurality of pixels sequentially; and

selecting said plurality of pixels sequentially after said storage period has passed since resetting said plurality of pixels.

28. The method according to claim 27 wherein a value of said storage period is set by irradiating said image pick up unit with light having a highest intensity among lights which have been reflected by an object to enter said image pick up unit.

29. The method according to claim 27 wherein the signals are outputted exclusively from those of the plurality of pixels of said image pick up unit that belong to a limited area.

30. A scanner using said MOS sensor according to claim 29.

31. A mobile information terminal using said MOS sensor according to claim 29.

32. A fingerprint reading device using said MOS sensor according to claim 29.

33. An electric apparatus having said MOS sensor according to claim 29 wherein said electronic apparatus is selected from the group consisting of a digital still camera, a mobile phone, a mobile game device, and a personal computer.

34. The method according to claim 27 wherein the image of an object is picked up by using said storage period.

35. A scanner using said MOS sensor according to claim 27.

36. A mobile information terminal using said MOS sensor according to claim 27.

37. A fingerprint reading device using said MOS sensor according to claim 27.

38. An electric apparatus having said MOS sensor according to claim 27 wherein said electronic apparatus is selected from the group consisting of a digital still camera, a mobile phone, a mobile game device, and a personal computer.

39. The method according to claim 27 wherein the first object is second object.

40. A driving method of a MOS sensor having a plurality of pixels in an image pick up unit, each of said pixels comprising:

a reset transistor;

a photoelectric conversion element having a first terminal connected to one of source or drain terminals of said reset transistor, and a second terminal connected to a photoelectric conversion element side power source line;

a reset signal line connected to a gate terminal of said reset transistor;

a signal amplifier circuit having an input terminal connected to said one of the source or drain terminals of said reset transistor;

a reset side power source line connected to other one of the source or drain terminals of said reset transistor;

said method comprising the steps of;

imaging a first object on trial, comprising the steps of;

resetting a part of said plurality of pixels at a same time; and

sequentially selecting the plurality of pixels to output signals of the selected pixels;

determining a storage period in accordance with a period from the time of said resetting to a time when any one of the photoelectric conversion elements of the selected pixels saturates; and

imaging a second object ordinarily, comprising the steps of;

resetting said plurality of pixels sequentially; and

selecting said plurality of pixels sequentially after said storage period has passed since resetting said plurality of pixels.

41. The method according to claim 40 wherein a value of said storage period is set by irradiating said image pick up unit with light having a highest intensity among lights which have been reflected by an object to enter said image pick up unit.

42. A scanner using said MOS sensor according to claim 41.

43. A mobile information terminal using said MOS sensor according to claim 41.

44. A fingerprint reading device using said MOS sensor according to claim 41.

45. An electric apparatus having said MOS sensor according to claim 41 wherein said electronic apparatus is selected from the group consisting of a digital still camera, a mobile phone, a mobile game device, and a personal computer.

46. The method according to claim 40 wherein the signals are outputted exclusively from those of the plurality of pixels of said image pick up unit that belong to a limited area.

47. A scanner using said MOS sensor according to claim 46.

48. A mobile information terminal using said MOS sensor according to claim 46.

49. A fingerprint reading device using said MOS sensor according to claim 46.

50. An electric apparatus having said MOS sensor according to claim 46 wherein said electronic apparatus is selected from the group consisting of a digital still camera, a mobile phone, a mobile game device, and a personal computer.

51. The method according to claim 40 wherein the image of an object is picked up by using said storage period.

52. A scanner using said MOS sensor according to claim 40.

53. A mobile information terminal using said MOS sensor according to claim 40.

54. A fingerprint reading device using said MOS sensor according to claim 40.

55. An electric apparatus having said MOS sensor according to claim 40 wherein said electronic apparatus is selected from the group consisting of a digital still camera, a mobile phone, a mobile game device, and a personal computer.

56. The method according to claim 40 wherein the first object is second object.

57. A MOS sensor comprising a plurality of pixels in an image pickup unit,

wherein said pixel includes a photoelectric conversion element, a resetting transistor and a signal amplifier circuit,

wherein said photoelectric conversion element is connected at its one terminal with the source terminal or drain terminal of said resetting transistor and at its other terminal with a photoelectric conversion element side power line,

wherein said resetting transistor is connected at its gate terminal with a reset signal line, and

wherein said resetting transistor is connected at its source terminal or drain terminal with said photoelectric conversion element and the input terminal of said signal amplifier circuit and at its other with a reset side power line,

whereby the pixels of said image pickup unit are sequentially selected, after all the plurality of the pixels reset simultaneously, so that the signals of the selected pixels are outputted, and

whereby the period from said reset time to the time when the signals of said selected pixels are saturated is set to the value of a storage period, and

whereby, in an ordinary imaging period, a plurality of second pixels of said image pickup unit are selected sequentially, after said storage period has passed since said plurality of second pixels were reset sequentially.

58. A MOS sensor according to claim 57 wherein the value of said storage period is set by irradiating said image pickup unit with that of the highest intensity of the lights which have been reflected by an object to enter said image pickup unit.

59. AMOS sensor according to claim 58 wherein the signals are outputted exclusively from those of the plurality of pixels of said image pickup unit that belong to a limited area.

60. A MOS sensor according to claim 58 wherein the image of an object is picked up by using said storage period.

61. The MOS sensor according to claim 57 wherein the plurality of first pixels are the plurality of second pixels.

62. A MOS sensor comprising a plurality of pixels in an image pickup unit,

wherein said pixel includes a photoelectric conversion element, a resetting transistor and a signal amplifier circuit,

wherein said photoelectric conversion element is connected at its one terminal with the source terminal or drain terminal of said resetting transistor and at its other terminal with a photoelectric conversion element side power line,

wherein said resetting transistor is connected at its gate terminal with a reset signal line, and

wherein said resetting transistor is connected at its source terminal or drain terminal with said photoelectric conversion element and the input terminal of said signal amplifier circuit and at its other with a reset side power line,

whereby the plurality of pixels of said image pickup unit are sequentially selected, after all reset simultaneously, so that the signals of the selected pixels are outputted, and

whereby the period from said reset time to the time when the signal having the largest amplitude of said selected pixels is saturated is set to the value of a storage period, and

whereby, in an ordinary imaging period, a plurality of second pixels of said image pickup unit are selected sequentially, after said storage period has passed since said plurality of second pixels were reset sequentially.

63. A MOS sensor according to claim 62 wherein the value of said storage period is set by irradiating said image pickup unit with that of the highest intensity of the lights which have been reflected by an object to enter said image pickup unit.

64. A MOS sensor according to claim 63 wherein the signals are outputted exclusively from those of the plurality of pixels of said image pickup unit that belong to a limited area.

65. A MOS sensor according to claim 63 wherein the image of an object is picked up by using said storage period.

66. The MOS sensor according to claim 62 wherein the plurality of first pixels are the plurality of second pixels.

67. A MOS sensor comprising a plurality of pixels in an image pickup unit,

wherein said pixel includes a photoelectric conversion element, a resetting transistor and a signal amplifier circuit,

wherein said photoelectric conversion element is connected at its one terminal with the source terminal or drain terminal of said resetting transistor and at its other terminal with a photoelectric conversion element side power line,

wherein said resetting transistor is connected at its gate terminal with a reset signal line, and

wherein said resetting transistor is connected at its source terminal or drain terminal with said photoelectric conversion element and the input terminal of said signal amplifier circuit and at its other with a reset side power line,

whereby the pixels of said image pickup unit are sequentially selected, after all the plurality of the pixels reset simultaneously, so that the signals of the selected pixels are outputted, and

whereby the period from said reset time to the time when the photoelectric conversion elements of said selected pixels are saturated is set to the value of a storage period, and

whereby, in an ordinary imaging period, a plurality of second pixels of said image pickup unit are selected sequentially, after said storage period has passed since said plurality of second pixels were reset sequentially.

68. A MOS sensor according to claim 67 wherein the value of said storage period is set by irradiating said image pickup unit with that of the highest intensity of the lights which have been reflected by an object to enter said image pickup unit.

69. AMOS sensor according to claim 67 wherein the signals are outputted exclusively from those of the plurality of pixels of said image pickup unit that belong to a limited area.

70. A MOS sensor according to claim 67 wherein the image of an object is picked up by using said storage period.

71. The MOS sensor according to claim 67 wherein the plurality of first pixels are the plurality of second pixels.

72. A MOS sensor comprising a plurality of pixels in an image pickup unit,

wherein said pixel includes a photoelectric conversion element, a resetting transistor and a signal amplifier circuit,

wherein said photoelectric conversion element is connected at its one terminal with the source terminal or drain terminal of said resetting transistor and at its other terminal with a photoelectric conversion element side power line,

wherein said resetting transistor is connected at its gate terminal with a reset signal line, and

wherein said resetting transistor is connected at its source terminal or drain terminal with said photoelectric conversion element and the input terminal of said signal amplifier circuit and at its other with a reset side power line,

whereby the plurality of pixels of said image pickup unit are sequentially selected, after all reset simultaneously, so that the signals of the selected pixels are outputted, and

whereby the period from said reset time to the time when any one of the photoelectric conversion elements of said selected pixels is saturated is set to the value of a storage period, and

whereby, in an ordinary imaging period, a plurality of second pixels of said image pickup unit are selected sequentially, after said storage period has passed since said plurality of second pixels were reset sequentially.

73. A MOS sensor according to claim 72 wherein the value of said storage period is set by irradiating said image pickup unit with that of the highest intensity of the lights which have been reflected by an object to enter said image pickup unit.

74. A MOS sensor according to claim 72 wherein the signals are outputted exclusively from those of the plurality of pixels of said image pickup unit that belong to a limited area.

76. The MOS sensor according to claim 72 wherein the plurality of first pixels are the plurality of second pixels.

75. A MOS sensor according to 72 wherein the image of an object is picked up by using said storage period.

77. A driving method of a MOS sensor having a plurality of pixels in an image pick up unit, each of said pixels comprising:

a reset transistor;

a photoelectric conversion element having a first terminal connected to one of source or drain terminals of said reset transistor, and a second terminal connected to a photoelectric conversion element side power source line;

a reset signal line connected to a gate terminal of said reset transistor;

a signal amplifier circuit having an input terminal connected to said one of the source or drain terminals of said reset transistor;

a reset side power source line connected to other one of the source or drain terminals of said reset transistor;

said method comprising the steps of;

imaging a first object on trial, comprising the steps of;

resetting said plurality of pixels at a same time; and

sequentially selecting a part of said plurality of pixels to output signals of the selected pixels;

determining a storage period in accordance with a period from the time of said resetting to a time when the signal of the selected pixels saturates; and

imaging a second object ordinarily, comprising the steps of;

resetting said plurality of pixels sequentially; and

selecting said plurality of pixels sequentially after said storage period has passed since resetting said plurality of pixels.