Image stabilizer

• US 7,590,336 B2
• Filed: 10/13/2005
• Issued: 09/15/2009
• Est. Priority Date: 10/14/2004
• Status: Expired due to Fees

• Current Assignee: Fujinon Corporation (Fujifilm Holdings Corporation)
• Original Assignee: Fujinon Corporation (Fujifilm Holdings Corporation)
• Inventors: Higo, Akira
• Primary Examiner(s): Koval; Melissa J
• Assistant Examiner(s): Smith; Linda B
• Application Number:
  US11/248,576
• Publication Number:
  US 20060083502A1
• Time in Patent Office: 1,433 Days
• Field of Search: 396/55, 396 52- 53, 348/208.99, 3482081-2085, 348/235, 348289-290, 348/342, 348/354, 324/76.39, 324/76.41, 324/123.R, 324/124, 324/128
• US Class Current: 396/55
• CPC Class Codes: G03B 2205/0007 Movement of one or more optical elements for control of motion blur
• CPC Class Codes: G03B 2217/005 Blur detection
• CPC Class Codes: G03B 5/00 Adjustment of optical system relative to image or object surface other than for focusing
• 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 23/6815 by distinguishing pan or tilt from motion
• CPC Class Codes: H04N 23/687 by shifting the lens or sensor position

Abstract

The present invention provides an image shake correcting apparatus including a shake signal output device, an image displacing device, and an image shake correcting device, comprising: a pan/tilt detecting device which detects panning or tilting of said optical system; an image shake correction stopping device which stops image shake correction by said image shake correcting device when said panning or tilting has been detected; a pan/tilt end detecting device which detects the end of said panning or tilting; an image shake correction restarting device which causes said image shake correcting device to resume image shake correction when the end of said panning or tilting has been detected; and an object frequency band altering device which raises, for a prescribed length of time after the resumption of said image shake correction, the cutoff frequency on the low frequency side of the frequency band covered by said image shake correction.

Claims

1. An image shake correcting apparatus including:

a shake signal output device which supplies a shake signal corresponding to a vibration working on an optical system;

an image displacing device which displaces an image formed by said optical system;

and an image shake correcting device which causes said image displacing device to so displace said image as to cancel any image shake due to the vibration working on said optical system on the basis of the shake signal supplied by said shake signal output device, the apparatus comprising;

a pan/tilt detecting device which detects panning or tilting of said optical system;

an image shake correction stopping device which stops image shake correction by said image shake correcting device when said panning or tilting has been detected based upon detection of the degree of vibration of the optical system;

a pan/tilt end detecting device which detects the end of said panning or tilting;

an image shake correction restarting device which causes said image shake correcting device to resume image shake correction when the end of said panning or tilting has been detected; and

an object frequency band altering device which raises, for a prescribed length of time after resumption of said image shake correction, a cutoff frequency on the low frequency side of the frequency band covered by said image shake correction.

2. The image shake correcting apparatus according to claim 1, wherein said object frequency band altering device reduces, by a prescribed value at a time at prescribed intervals of time, a cutoff frequency on the low frequency side of the frequency band covered by said image shake correction.

4. The image shake correcting apparatus according to claim 1, wherein, in the pan/tilt detecting device, when an absolute value of an angular velocity signal is greater than a first threshold, it is judged that the panning or tilting has been performed and when an absolute value of an angular velocity signal after the detection of panning or tilting fails below a second threshold, it is judged that the panning or tilting has ended.

3. A method of correcting for image shake in an optical system comprising:

detecting panning or tilting of said optical system,

stopping image shake correction by an image shake correction device when panning or tilting has been detected based upon detection of the degree of vibration of the optical system,

detecting the end of said panning or tilting,

restarting image shake correction when the end of said panning or tilting is detected, and

raising the cutoff frequency on the low frequency side of the frequency band covered by said image shake correction for a prescribed length of time after the resumption of said image shake correction.

5. A method of correcting for image shake in an optical system according to claim 3, wherein, in the step of detecting the end of said panning or tilting, when an absolute value of an angular velocity signal is greater than a first threshold, it is judged that the panning or tilting has been performed and when an absolute value of an angular velocity signal after the detection of panning or tilting falls below a second threshold, it is judged that the panning or tilting has ended.