Image blur prevention device

• US 6,035,133 A
• Filed: 04/14/1997
• Issued: 03/07/2000
• Est. Priority Date: 07/17/1995
• Status: Expired due to Term

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Shiomi, Yasuhiko
• Primary Examiner(s): Perkey, W. B.
• Application Number:
  US08/834,128
• Time in Patent Office: 1,058 Days
• Field of Search: 396/55, 396/52, 348/208, 359/554-557
• US Class Current: 396/55
• CPC Class Codes: G03B 17/00 Details of cameras or camera bodies; Accessories therefor lens hoods or caps G03B11/04
• CPC Class Codes: G03B 2217/005 Blur detection
• CPC Class Codes: H04N 23/68 for stable pick-up of the scene, e.g. compensating for camera body vibrations
• CPC Class Codes: H04N 23/6812 based on additional sensors, e.g. acceleration sensors
• CPC Class Codes: H04N 23/687 by shifting the lens or sensor position
• CPC Class Codes: H04N 23/689 Motion occurring during a rolling shutter mode

Abstract

Proper image blur prevention is performed when a fluctuation of an optical apparatus (camera) is caused by the operation of a movable member (operation of the shutter of the camera). For this purpose, an image blur prevention apparatus is operated by using both an output signal from a detection device (e.g., a detection system including a vibration gyroscope and the like) and a predetermined signal (e.g., a signal having a predetermined waveform and stored in a memory) so that the image blur caused by a fluctuation due to an operation of the movable member can be properly prevented.

Claims

1. An apparatus for preventing image blur and adapted for use with a camera including a movable member and an operation portion that performs a predetermined operation for moving the movable member, said apparatus comprising:

a fluctuation detection device that detects a fluctuation of the apparatus;

a memory that stores a predetermined signal;

signal forming means for forming a driving signal for driving an image blur correction means in accordance with an output of said fluctuation detection device and a signal stored in said memory;

timing means for measuring an elapsed time in response to the predetermined operation of the operation portion of the camera for moving the movable member; and

control means for controlling a signal forming operation of said signal forming means in accordance with the elapsed time measured by said timing means.

2. An apparatus according to claim 1, wherein the movable member includes a shutter, and the predetermined operation of said operation portion includes a release operation of the camera.

3. An apparatus according to claim 2, wherein the movable member includes a focal plane shutter.

4. An apparatus according to claim 1, wherein said signal forming means includes means for forming said driving signal by adding the output from the fluctuation detection device to the predetermined signal stored in said memory.

7. An apparatus according to claim 1, wherein said control means includes means for controlling a timing of said signal forming operation using the predetermined signal stored in said memory in accordance with the elapsed time measured by said timing means.

8. An apparatus according to claim 7, wherein said control means includes means for causing said signal forming means to start a signal forming operation by adding the output of said fluctuation detection device to the predetermined signal stored in said memory at a timing when said timing means measures a predetermined time from the start of operation of said operation portion.

9. An apparatus according to claim 7, wherein said memory includes means for storing a predetermined signal having a value which varies at a predetermined rate.

10. An apparatus according to claim 9, wherein said memory includes means for storing a predetermined signal having a value which increases monotonously in at least a predetermined period.

11. An apparatus according to claim 9, wherein said control means includes means for varying a maximum amount of variation of the predetermined signal stored in said memory in accordance with the elapsed time measured by said timing means.

12. An apparatus according to claim 11, wherein said control means includes means for holding the variable, predetermined signal stored in said memory substantially at a constant value when said timing means measures a predetermined time from the start of operation of said operation portion.

13. An apparatus according to claim 7, wherein said control means includes means for varying a timing of performing said signal forming operation using the predetermined signal stored in said memory in accordance with the elapsed time measured by said timing means.

14. An apparatus according to claim 8, wherein said control means includes means for varying a timing for performing said signal forming operation in accordance with a shutter speed of the camera, zooming information, focusing information, a diaphragm value or a signal transmitted from the camera.

15. An apparatus according to claim 1, wherein said memory includes means for outputting a predetermined wave-formed signal as a memory signal and said control means includes means for varying a wave form of said predetermined wave-form signal in accordance with a shutter speed of the camera, zooming information, focusing information, a diaphragm value or a signal transmitted from the camera.

48. An apparatus according to claim 1, wherein said timing means includes means for measuring a time in accordance with a start of a sequence for moving the movable member responsive to said predetermined operation.

49. An apparatus according to claim 48, wherein said movable member includes a shutter member and said timing means includes means for measuring a time in accordance with a start of an actual shutter release sequence of the camera, the start corresponding to an operation for performing a shutter release of a release operation portion.

50. An apparatus according to claim 1, further comprising:

image blur correction control means for starting a driving of said image blur correction means in response to the predetermined operation of the operation portion of the camera, the driving of said image blur correction means being in response to the driving signal formed in accordance with the output of said fluctuation detection device and the signal stored in said memory.

51. An apparatus according to claim 50, wherein said image blur correction control means includes changing means for changing a first state in which said image blur correction means is driven in response to the output of said fluctuation detection device but unresponsive to the signal stored in said memory to a second state in which said image blur correction means is driven in response to the driving signal formed by said signal forming means in accordance with the output of said fluctuation detection device and the signal stored in said memory.

52. An apparatus according to claim 50, wherein said image blur correction control means includes means for starting a driving of said image blur correction means in response to the driving signal formed by said signal forming means, in accordance with a start of a sequence for moving said movable member in response to the predetermined operation.

53. An apparatus according to claim 52, wherein said movable member includes a shutter member and said image blur correction control means includes means for starting a driving of said image blur correction means in response to the driving signal formed by said signal forming means, in accordance with a start of an actual shutter release sequence of the camera in response to operation for performing a shutter release of a release operation portion.

5. An image blur prevention apparatus adapted for use with a camera including a movable member and an operation portion that performs a predetermined operation for moving the movable member, said apparatus comprising:

an image blur correction device that corrects image blur;

a fluctuation detection device that detects a fluctuation of the apparatus;

a memory that stores a predetermined signal;

signal forming means for forming a driving signal for driving said image blur correction device in accordance with an output of said fluctuation detection device and the predetermined signal stored in said memory;

timing means for measuring an elapsed time in response to the predetermined operation of the operation portion of the camera for moving the movable member; and

control means for controlling a signal forming operation of said signal forming means in accordance with the elapsed time measured by said timing means.

6. An apparatus for preventing image blur and adapted for use with an optical equipment including a movable member and an operation portion that performs a predetermined operation for moving the movable member, said apparatus comprising:

a fluctuation detection device that detects a fluctuation of the apparatus;

a memory that stores a predetermined signal;

signal forming means for forming a driving signal for driving an image blur correction means in accordance with an output of said fluctuation detection device and the predetermined signal stored in said memory;

timing means for measuring an elapsed time in response to the predetermined operation of the operation portion of the optical equipment for moving the movable member; and

control means for controlling a signal forming operation of said signal forming means in accordance with the elapsed time measured by said timing means.

16. An apparatus for preventing image blur and adapted for use with a camera including a movable member, said apparatus comprising:

a fluctuation detection device that detects a fluctuation of said apparatus;

a memory that stores a signal, the value of which increases or decreases substantially monotonously; and

signal forming means for forming a driving signal for driving image blur correction means for correcting image blur in accordance with an output of said fluctuation detection device and a signal stored in said memory, the signal stored in said memory being used for a signal forming operation performed at a timing corresponding to a movement of said movable member, and including substantially no element reverse to a monotonous increasing or decreasing variation of the signal value.

17. An apparatus according to claim 16, wherein said memory includes means for storing two parameters such as a time and an amplitude of the signal.

18. An apparatus according to claim 16, wherein said memory includes means for outputting a stored signal in accordance with a timing operation of a predetermined timing device.

19. An apparatus according to claim 18, wherein said predetermined timing device includes means for performing a timing operation in accordance with a predetermined operation of an operation portion for moving said movable member.

20. An apparatus according to claim 18, wherein said memory includes means for starting an output of the stored signal, the value of which is in a predetermined range of monotonous variation, to said signal forming means when said timing device measures a predetermined time.

21. An apparatus according to claim 20, wherein said memory includes means for stopping the output of the signal, the value of which is in the predetermined range of monotonous variation, and for starting an output of a signal having a value that is substantial constant when said timing means measures a second time, longer than said predetermined time.

22. An apparatus according to claim 16, wherein said movable member includes a shutter.

23. An apparatus according to claim 22, wherein said movable member includes a focal plane shutter.

24. An apparatus according to claim 23, wherein said focal plane shutter includes a leading curtain and a trailing curtain and said memory includes means for outputting the signal, the value of which is in said predetermined range of variation when said leading curtain is being driven.

25. An apparatus according to claim 16, wherein said signal forming means includes means for forming said driving signal by adding the output of said fluctuation detection device to a predetermined signal stored in said memory.

26. An apparatus according to claim 18, wherein said memory includes means for varying an output timing of said stored signal.

27. An apparatus according to claim 26, wherein said memory includes means for varying the output timing of said stored signal in accordance with a shutter speed of the camera, zooming information, focusing information, a diaphragm value or a signal transmitted from the camera.

28. An apparatus according to claim 16, wherein said memory includes means for varying a wave form of an output signal in accordance with a shutter speed of the camera, zooming information, focusing information, a diaphragm value or a signal transmitted from the camera.

29. An image blur prevention apparatus adaptable to a plurality of kinds of cameras, said apparatus comprising:

a fluctuation detection device that detects a fluctuation of said apparatus;

signal output means for outputting a signal having a predetermined wave form;

driving signal forming means for outputting a driving signal for driving an image blur correction means in accordance with an output of said fluctuation detection device and an output signal of said signal output means;

signal receiving means for receiving a signal transmitted from a camera; and

varying means for varying a wave form or a timing of a signal output from said signal output means in accordance with the signal received by said signal receiving means.

30. An apparatus according to claim 29, wherein said varying means includes means for varying a timing at which said signal output means starts to output the signal having said predetermined wave form.

31. An apparatus according to claim 29, wherein said driving signal forming means includes means for causing an operation state thereof to be selectable between a first state in which the driving signal responsive to the output of said fluctuation detection device but unresponsive to the output signal of said signal output means is output and a second state in which the driving signal responsive to both of the output of said fluctuation detection device and the output signal of said signal output means is output.

32. An apparatus according to claim 31, wherein said varying means includes means for varying a timing at which said driving signal forming means changes the operation state from said first state to said second state by varying said signal output start timing of said signal output means.

33. An apparatus according to claim 29, wherein said varying means includes means for varying a varying ratio of the signal having said predetermined wave form output from said signal output means.

34. An apparatus according to claim 29, wherein said varying means includes means for varying a timing at which the varying ratio of the signal having said predetermined wave form output from said signal output means is varied.

35. An apparatus according to claim 29, wherein said signal output means includes means for outputting a signal having a wave form or a timing in accordance with a predetermined parameter.

36. An apparatus according to claim 35, wherein said varying means includes means for varying said parameter in accordance with the signal received by said signal receiving means.

37. An apparatus according to claim 35, wherein said signal output means includes timing means and means for outputting a signal in accordance with said parameter and a measured time of said timing means.

38. An apparatus according to claim 29, wherein said signal receiving means includes means for receiving plural kinds of signals transmitted from the camera, and said varying means includes means for varying said wave form or said timing in accordance with said plural kinds of signals.

39. An apparatus according to claim 29, wherein said driving signal forming means includes means for starting to form a driving signal in accordance with the outputs of said fluctuation detection device and said signal output means, both signals being responsive to a predetermined signal transmitted from the camera.

40. An apparatus according to claim 39, wherein said signal output means includes means for starting to output the signal having said predetermined wave form in accordance with said predetermined signal transmitted from the camera.

41. An apparatus according to claim 39, wherein said varying means includes means for determining said wave form or said timing in accordance with a signal transmitted from the camera before said predetermined signal.

42. An apparatus according to claim 39, wherein said driving signal forming means includes means for starting to form a driving signal in accordance with the outputs of said fluctuation detection device and said signal output means, both signals being responsive to a predetermined signal transmitted from the camera in accordance with a shutter release operation of the camera.

43. An apparatus according to claim 42, wherein said driving signal forming means includes means for starting to form a driving signal in accordance with the outputs of said fluctuation detection device and said signal output means, both signals being responsive to a predetermined signal transmitted from the camera in accordance with a start of an actual shutter release sequence of the camera.

44. An apparatus according to claim 39, wherein said driving signal forming means includes means for starting to form a driving signal in accordance with the outputs of said fluctuation detection device and said signal output means, both signals being responsive to a predetermined signal transmitted from the camera in accordance with a predetermined operation of a release operation portion for causing the camera to release a shutter.

45. An apparatus according to claim 29, wherein said varying means includes means for determining said wave form or said timing in accordance with a signal transmitted from the camera, corresponding to a mounted state of accessories of the camera.

46. An apparatus according to claim 45, wherein said varying means includes means for determining said wave form or said timing in accordance with a signal transmitted from the camera, corresponding to a mounted state of an external power supply or a stroboscopic lamp apparatus of the camera.

47. An apparatus according to claim 29, wherein said driving signal forming means includes means for forming the driving signal by adding the output signals of said fluctuation detection device to the output signal of said signal output means.