ANGULAR VELOCITY DETECTION APPARATUS

• US 20080084479A1
• Filed: 10/09/2007
• Published: 04/10/2008
• Est. Priority Date: 10/10/2006
• Status: Active Grant

• Current Assignee: PENTAX RICOH IMAGING COMPANY, LTD.
• Original Assignee: C/O Pentax Corporation
• Inventors: UENAKA, Yukio
• Granted Patent: US 7,683,936 B2
• Time in Patent Office: Days
• US Class Current: 348/208.5
• CPC Class Codes: G03B 5/00 Adjustment of optical system relative to image or object surface other than for focusing

Abstract

An angular-velocity detector comprises a first sensor, a second sensor, and a controller. The first sensor is used for detecting motion around an axis of a second direction perpendicular to a first direction. The second sensor is used for detecting motion around an axis of the first direction. The controller performs an operation that corrects an output error caused by an angle of inclination of the second sensor by using a first correction coefficient that is a ratio of a second amplitude to a first amplitude. The first amplitude is amplitude of output value from the first sensor when the angular-velocity detector is in first motion around an axis of the second direction without second motion around an axis of the first direction. The second amplitude is amplitude of output value from the second sensor when the angular-velocity detector is in the first motion without the second motion.

Claims

1. An anti-shake apparatus for image stabilizing, comprising:

a first angular velocity sensor that is used for detecting a motion around an axis of a second direction, said second direction being perpendicular to a first direction and an optical axis of a photographing optical system, said first direction being perpendicular to said optical axis;

a second angular velocity sensor that is used for detecting a motion around an axis of said first direction; and

a controller that controls said first and second angular velocity sensors, performs an anti-shake operation based on an output signal from said first angular velocity sensor and an output signal from said second angular velocity sensor, and performs a first angular error correction processing operation and a second angular error correction processing operation in said anti-shake operation;

in said second angular error correction processing operation, an output error caused by an angle of inclination of said second angular velocity sensor being corrected by using a first correction coefficient that is a ratio of a second amplitude to a first amplitude;

in said first angular error correction processing operation, an output error caused by an angle of inclination of said first angular velocity sensor being corrected by using a second correction coefficient that is a ratio of a third amplitude to a fourth amplitude;

said first amplitude being an amplitude of an output value from said first angular velocity sensor when said anti-shake apparatus is in a first motion around an axis of said second direction, but is not in a second motion around an axis of said first direction;

said second amplitude being an amplitude of an output value from said second angular velocity sensor when said anti-shake apparatus is in said first motion, but is not in said second motion;

said third amplitude being an amplitude of an output value from said first angular velocity sensor when said anti-shake apparatus is in said second motion, but is not in said first motion; and

said fourth amplitude being an amplitude of an output value from said second angular velocity sensor when said anti-shake apparatus is in said second motion, but is not in said first motion.

2. The anti-shake apparatus according to claim 1, wherein said inclination of said first angular velocity sensor is indicated by an angle between a detection axis of said first angular velocity sensor and said second direction;

and

said inclination of said second angular velocity sensor is indicated by an angle between a detection axis of said second angular velocity sensor and said first direction.

3. The anti-shake apparatus according to claim 1, wherein said first angular error correction processing operation is a calculation of a product of said output signal from said second angular velocity sensor and said second correction coefficient, that is then subtracted from said output signal of said first angular velocity sensor;

and

said second angular error correction processing operation is a calculation of a product of said output signal from said first angular velocity sensor and said first correction coefficient, that is then subtracted from said output signal of said second angular velocity sensor.

4. An angular velocity detection apparatus comprising:

a first angular velocity sensor that is used for detecting a motion around an axis of a second direction, said second direction being perpendicular to a first direction;

a second angular velocity sensor that is used for detecting a motion around an axis of said first direction; and

a controller that controls said first and second angular velocity sensors, and performs a first angular error correction processing operation and a second angular error correction processing operation;

in said second angular error correction processing operation, an output error caused by an angle of inclination of said second angular velocity sensor being corrected by using a first correction coefficient that is a ratio of a second amplitude to a first amplitude;

in said first angular error correction processing operation, an output error caused by an angle of inclination of said first angular velocity sensor being corrected by using a second correction coefficient that is a ratio of a third amplitude to a fourth amplitude;

said first amplitude being an amplitude of an output value from said first angular velocity sensor when said angular velocity detection apparatus is in a first motion around an axis of said second direction, but is not in a second motion around an axis of said first direction;

said second amplitude being an amplitude of an output value from said second angular velocity sensor when said angular velocity detection apparatus is in said first motion, but is not in said second motion;

said third amplitude being an amplitude of an output value from said first angular velocity sensor when said angular velocity detection apparatus is in said second motion, but is not in said first motion; and

said fourth amplitude being an amplitude of an output value from said second angular velocity sensor when said angular velocity detection apparatus is in said second motion, but is not in said first motion.