Optical device

• US 7,498,729 B2
• Filed: 08/15/2006
• Issued: 03/03/2009
• Est. Priority Date: 08/16/2005
• Status: Expired due to Fees

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Ogino, Shigeru
• Primary Examiner(s): Dougherty; Thomas M
• Assistant Examiner(s): Addison; Karen B
• Application Number:
  US11/464,710
• Publication Number:
  US 20070040481A1
• Time in Patent Office: 931 Days
• Field of Search: 310/800, 310/328, 310/330, 310/311, 359/557, 359/824, 359/823
• US Class Current: 310/330
• CPC Class Codes: G02B 7/023 permitting adjustment
• CPC Class Codes: G02B 7/08 adapted to co-operate with a remote control mechanism
• CPC Class Codes: H02N 11/006 Motors
• CPC Class Codes: Y10S 310/80 Piezoelectric polymers, e.g. PVDF

Abstract

An optical device includes a lens holder that holds a lens and is movable in the optical-axis direction of the lens, and an actuator that moves the lens holder in the optical-axis direction. The actuator includes an actuator element composed of an electroactive polymer, an actuator-element holder that holds the actuator element, a mechanism that applies prestrain to the actuator element, and a connecting member that connects the lens holder and the actuator. Herein, a connecting portion of the connecting member is disposed adjacent to the side surface of the actuator.

Claims

1. An optical device comprising:

a lens holder that holds a lens and is movable in the optical-axis direction of the lens; and

an actuator that moves the lens holder in the optical-axis direction, the actuator including an actuator element composed of an electroactive polymer, an actuator-element holder that holds the actuator element, a mechanism that applies prestrain to the actuator element, and a connecting member that connects the lens holder and the actuator, wherein

a connecting portion of the connecting member is disposed adjacent to the side surface of the actuator element, and

wherein the prestrain to the actuator element is applied in a direction to which the lens holder moves.

2. The optical device according to claim 1, wherein

the mechanism includes a flat plate.

3. The optical device according to claim 1, wherein

the mechanism includes a stepped shaft.

4. The optical device according to claim 1, wherein

the actuator further includes another actuator element.

5. The optical device according to claim 1, wherein

the actuator element is tubular.

6. The optical device according to claim 1, wherein

the actuator element is one or more ring-shaped sheet actuator elements;

and

the actuator elements are connected to form a bellows shape.