Photographic apparatus with image stabilization and controller for calculating and correcting inclination angle

• US 7,962,021 B2
• Filed: 03/26/2009
• Issued: 06/14/2011
• Est. Priority Date: 03/31/2008
• Status: Expired due to Fees

• Current Assignee: PENTAX RICOH IMAGING COMPANY, LTD.
• Original Assignee: Hoya Corporation
• Inventors: Uenaka, Yukio
• Primary Examiner(s): Perkey; W. B.
• Assistant Examiner(s): ADAMS, BRET W
• Application Number:
  US12/411,477
• Publication Number:
  US 20090245771A1
• Time in Patent Office: 810 Days
• Field of Search: 396/53
• US Class Current: 396/55
• CPC Class Codes: G03B 2205/0038 by displacing the image plane with respect to the optical axis in case of an electronic image sensor H04N23/68
• 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

A photographic apparatus comprises a movable platform, an acceleration sensor, and a controller. The movable platform has an imager, and is movable and rotatable in an xy plane. The acceleration sensor detects a first gravitational component and a second gravitational component. The first gravitational component is the component of gravitational acceleration in the x direction. The second gravitational component is the component of gravitational acceleration in the y direction. The controller calculates an inclination angle of the photographic apparatus formed by rotation of the photographic apparatus around the optical axis, as measured with respect to a level plane perpendicular to the direction of gravitational force, on the basis of a magnitude relation between the absolute value of the first gravitational component and the absolute value of the second gravitational component, and performs a first movement control of the movable platform for an inclination correction based on the inclination angle.

Claims

1. A photographic apparatus comprising:

a movable platform which has an imager that captures an optical image through a taking lens, and is movable and rotatable in an xy plane perpendicular to an optical axis of said taking lens;

an acceleration sensor that detects a first gravitational component and a second gravitational component, said first gravitational component being a component of gravitational acceleration in an x direction perpendicular to said optical axis, and said second gravitational component being a component of gravitational acceleration in a y direction perpendicular to said optical axis and said x direction; and

a controller that calculates an inclination angle of said photographic apparatus formed by rotation of said photographic apparatus around said optical axis, as measured with respect to a level plane perpendicular to a direction of gravitational force, on the basis of a magnitude relation between an absolute value of said first gravitational component and an absolute value of said second gravitational component, and performs a first movement control of said movable platform for an inclination correction based on said inclination angle,

wherein said controller calculates said inclination angle by performing an arcsine transformation on the smaller of the absolute value of said first gravitational component and the absolute value of said second gravitational component.

2. The photographic apparatus according to claim 1, wherein said controller performs said first movement control and a second movement control of said movable platform for stabilization, including at least one of a first stabilization for correcting hand shake caused by yaw around said y direction and a second stabilization for correcting hand shake caused by pitch around said x direction.

3. The photographic apparatus according to claim 1, wherein said x direction is perpendicular to the direction of gravitational force and said y direction is parallel to the direction of gravitational force when said photographic apparatus is held horizontally and either an upper surface or a lower surface of said photographic apparatus faces upward;

and

said x direction is parallel to the direction of gravitational force and said y direction is perpendicular to the direction of gravitational force when said photographic apparatus is held vertically and a side surface of said photographic apparatus faces upward.