Motion detector and image capture device, interchangeable lens and camera system including the motion detector

• US 7,973,820 B2
• Filed: 05/15/2008
• Issued: 07/05/2011
• Est. Priority Date: 05/17/2007
• Status: Expired due to Fees

• Current Assignee: Panasonic Corporation (Panasonic Holdings Corporation)
• Original Assignee: Panasonic Corporation (Panasonic Holdings Corporation)
• Inventors: Kishimoto, Yoshiyuki, Ohara, Masamichi, Yamane, Yosuke
• Primary Examiner(s): Misleh; Justin P
• Application Number:
  US12/121,142
• Publication Number:
  US 20090309983A1
• Time in Patent Office: 1,146 Days
• Field of Search: 348/208.99, 348/208.2, 348/208.3, 348/208.14, 348/208.16, 386/242
• US Class Current: 348/208.3
• 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

Abstract

The blurring caused by a tiny tremor movement is eliminated, which almost perfectly without being affected by intentional camera movement by distinguishing the unintentional tremor movement from other movements (or disturbances). A motion detector includes: a motion detecting section for detecting a movement of an image capture device and outputting a detection signal, of which the amplitude and frequency represent the movement; a motion signal generating section for generating a motion signal representing a physical quantity corresponding to the magnitude of the movement based on the detection signal; a notification signal generating section for generating a notification signal that marks start and end of a movement of the image capture device, which is a non-tremor movement, based on the detection signal that has been output; and a control section for controlling the motion signal generating section by reference to the notification signal such that an output of the motion signal is fixed at a predetermined one from the start through the end of the non-tremor movement.

Claims

1. A motion detector comprising:

a motion detecting section for detecting a movement of an image capture device and outputting a detection signal, of which the amplitude and frequency represent the movement;

a motion signal generating section for generating a motion signal representing a physical quantity corresponding to the magnitude of the movement based on the detection signal;

a notification signal generating section for generating a notification signal that marks start and end of a movement of the image capture device, which is a non-tremor movement, based on the detection signal that has been output; and

a control section for controlling the motion signal generating section by reference to the notification signal such that an output level of the motion signal is fixed at a predetermined one from the start through the end of the non-tremor movement.

2. The motion detector of claim 1, wherein the motion signal generating section includes an analog circuit and a digital circuit.

3. The motion detector of claim 2, wherein the digital circuit of the motion signal generating section includes an integrator, and

wherein the integrator integrates the detection signal that has been processed by the analog and digital circuits, thereby generating the motion signal representing the physical quantity corresponding to the magnitude of the movement.

4. The motion detector of claim 3, wherein the notification signal generating section detects, as a variation point of the notification signal, a point where a waveform of the notification signal changes in an impulse form.

5. The motion detector of claim 4, wherein the control section stores first and second threshold values that have been defined in advance, and

wherein when the notification signal passes through the first threshold value, the control section senses that the non-tremor movement has started, and

wherein when the notification signal passes through the second threshold value after the start of the non-tremor movement has been sensed, the control section senses that the non-tremor movement has ended.

6. The motion detector of claim 4, wherein the control section stores a predefined threshold value, and

wherein when the notification signal passes through the threshold value, the control section senses that the non-tremor movement has started, and

wherein when the notification signal stays within a predetermined amplitude range for a predetermined amount of time, the control section senses that the non-tremor movement has ended.

7. The motion detector of claim 4, wherein the control section controls the motion signal generating section so as to fix the detection signal at a predetermined level before the motion signal generating section integrates the detection signal.

8. The motion detector of claim 7, wherein the control section controls the motion signal generating section such that the analog circuit of the motion signal generating section fix the detection signal at the predetermined level.

9. The motion detector of claim 7, wherein the control section controls the motion signal generating section such that the digital circuit of the motion signal generating section fix the detection signal at the predetermined level.

10. The motion detector of claim 7, wherein the control section controls the motion signal generating section such that both the analog and digital circuits of the motion signal generating section fix the detection signal at the predetermined level.

11. The motion detector of claim 1, wherein the control section controls the motion signal generating section such that the detection signal is unfixed from the predetermined level in the vicinity of a zero-cross point of the detection signal.

12. The motion detector of claim 1, wherein the notification signal generating section generates the notification signal that marks the start and end of the non-tremor movement of the image capture device based on frequency of the detection signal.

13. An image capture device comprising an imager and an optical system to form an image of a subject, the device further comprising:

a motion detecting section for detecting a movement of the image capture device and outputting a detection signal, of which the amplitude and frequency represent the movement;

a motion signal generating section for generating a motion signal representing a physical quantity corresponding to the magnitude of the movement based on the detection signal;

a notification signal generating section for generating a notification signal that marks start and end of a movement of the image capture device, which is a non-tremor movement, based on the detection signal that has been output; and

a control section for controlling the motion signal generating section by reference to the notification signal such that an output level of the motion signal is fixed at a predetermined one from the start through the end of the non-tremor movement.

14. The image capture device of claim 13, wherein the optical system includes an image stabilizer lens, of which the positions are changed in response to a drive signal, and

wherein the image capture device further includes a lens driver that shifts the image stabilizer lens in response to the motion signal, and

wherein the lens driver shifts an optical axis of the image stabilizer lens such that an optical axis of the optical system is aligned, and then kept aligned, with that of the imager in accordance with the motion signal.

15. The image capture device of claim 13, further comprising a driver for shifting the imager in response to the motion signal,

wherein the driver shifts the imager in response to the motion signal such that the image of the subject that has been incident on the imager from the optical system does not move but stays at a predetermined location on the imager.

16. An image capture device with an imager comprising:

an optical system to form an image of a subject by collecting light from the subject;

a driver for driving a part or all of the optical system within a plane that is perpendicular to an optical axis of the optical system;

a motion detecting section for detecting a movement of the image capture device and outputting a motion signal representing a detection result; and

a processor for stabilizing the image of the subject due to the movement of the image capture device, having;

a first control mode for controlling, based on the motion signal that has been output, the driver which drives a part or all of the optical system; and

a second control mode for controlling the driver not based on the motion signal,

wherein the processor selects one of the first control mode and second control mode by reference to the motion signal and controls the driver in the selected control mode.

17. An image capture device having an optical system to form an image of a subject by collecting light from the subject and an imager for imaging the image of the subject,

the device comprising:

a driver for driving the imager within a plane that is perpendicular to an optical axis of the optical system;

a motion detecting section for detecting a movement of the image capture device and outputting a motion signal representing a detection result; and

a processor for stabilizing the image of the subject due to the movement of the image capture device, having;

a first control mode for controlling, based on the motion signal that has been output, the driver which drives the imager; and

a second control mode for controlling the driver not based on the motion signal,

wherein the processor selects one of the first control mode and second control mode by reference to the motion signal and controls the driver in the selected control mode.

18. An interchangeable lens for use in an image capture device, of which the lens is replaceable with the interchangeable lens,

the interchangeable lens comprising:

an optical system to form an image of a subject;

a motion detecting section for detecting a movement of the interchangeable lens and outputting a detection signal, of which the amplitude and frequency represent the movement;

a motion signal generating section for generating a motion signal representing a physical quantity corresponding to the magnitude of the movement based on the detection signal;

a notification signal generating section for generating a notification signal that marks start and end of a movement of the interchangeable lens, which is a non-tremor movement, based on the detection signal that has been output; and

a control section for controlling the motion signal generating section by reference to the notification signal such that an output level of the motion signal is fixed at a predetermined one from the start through the end of the non-tremor movement.

19. A camera system comprising an interchangeable lens and a camera body,

wherein the interchangeable lens includes:

a motion detecting section for detecting a movement of the interchangeable lens and outputting a detection signal, of which the amplitude and frequency represent the movement; and

a first communication section, and

wherein the camera body includes;

a second communication section to be connected to the first communication section; and

a signal processor for receiving a detection signal through the first and second communication sections and generating a motion signal representing a physical quantity corresponding to the magnitude of the movement based on the detection signal, and

wherein the signal processor includes;

a notification signal generating section for generating a notification signal that marks start and end of a movement of the camera body, which is a non-tremor, based on the frequency of the detection signal; and

a control section for controlling the motion signal generating section by reference to the notification signal such that an output level of the motion signal is fixed at a predetermined one from the start through the end of the non-tremor movement.