TWO DIMENSIONAL POSITION DETECTING DEVICE

• US 20060250504A1
• Filed: 01/03/2006
• Published: 11/09/2006
• Est. Priority Date: 01/07/2005
• Status: Active Grant

• Current Assignee: Pentax Corporation (Hoya Corporation)
• Original Assignee: Pentax Corporation (Hoya Corporation)
• Inventors: SEO, Shuzo
• Granted Patent: US 7,352,477 B2
• Time in Patent Office: Days
• US Class Current: 348/208.110
• CPC Class Codes: G03B 2207/005 involving 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 23/55 Optical parts specially adapted for electronic image sensors; Mounting thereof
• CPC Class Codes: H04N 23/60 Control of cameras or camera modules
• CPC Class Codes: H04N 23/68 for stable pick-up of the scene, e.g. compensating for camera body vibrations
• CPC Class Codes: H04N 23/687 by shifting the lens or sensor position

Abstract

A two-dimensional position detecting device includes a movable member which relatively moves parallel to a stationary member; a light source and a two-dimensional position sensor which are fixed to one and the other of the stationary member and the movable member, respectively, the two-dimensional position sensor receiving light emitted from the light source to detect a light-receiving point on a light receiving surface of the two-dimensional position sensor; and a reducing projector optical system, positioned between the light source and the two-dimensional position sensor, for converging the light that is emitted from the light source on the light receiving surface of the two-dimensional position sensor.

Claims

1. A two-dimensional position detecting device comprising:

a movable member which relatively moves parallel to a stationary member;

a light source and a two-dimensional position sensor which are fixed to one and the other of said stationary member and said movable member, respectively, said two-dimensional position sensor receiving light emitted from said light source to detect a light-receiving point on a light receiving surface of said two-dimensional position sensor; and

a reducing projector optical system, positioned between said light source and said two-dimensional position sensor, for converging said light that is emitted from said light source on said light receiving surface of said two-dimensional position sensor.

2. The two-dimensional position detecting device according to claim 1, wherein said reducing projector optical system comprises an imaging lens positioned so that a distance between said imaging lens and said light source is greater than a distance between said imaging lens and said two-dimensional position sensor.

3. The two-dimensional position detecting device according to claim 1, wherein said movable member comprises a movable stage of an image shake correction stage apparatus, and

wherein said movable stage is supported by a first support device in a manner to allow said movable stage to move freely in one of two axial directions perpendicular to each other relative to said stationary member, and wherein said movable stage is further supported by said stationary member via a second support device to allow said first support device and said movable stage to integrally move linearly in the other of said two axial directions.

4. The two-dimensional position detecting device according to claim 1, wherein said reducing projector optical system comprises an imaging lens and an adjuster for moving said image lens in a small moving range for fine focus adjustment.

5. The two-dimensional position detecting device according to claim 3, wherein said image shake correction stage apparatus is incorporated in a digital camera.

6. The two-dimensional position detecting device according to claim 5, wherein said camera comprises:

an X-direction actuator which moves said movable stage in said one of said two axial directions relative to said stationary member;

a Y-direction actuator which moves said first support device and said movable stage in said other of said two axial directions relative to said stationary member; and

a controller for driving said X-direction actuator and said Y-direction actuator in accordance with an output of said two-dimensional position sensor to stabilize an object image which is formed on an image pickup device through a photographing optical system of said camera.

7. The two-dimensional position detecting device according to claim 3, wherein said first support device and said second support device comprise a substantially U-shaped guide shaft which includes a guide shaft extending in said other of said two axial directions and two parallel guide shafts extending in said one of said two axial directions.

8. The two-dimensional position detecting device according to claim 4, wherein said adjuster comprises two hollow-cylindrical members,

wherein one of said two hollow-cylindrical members is fixed to said two-dimensional position sensor and the other of said two hollow-cylindrical members supports said imaging lens;

and

wherein a position of said imaging lens in the optical axis direction thereof is finely adjusted via a sliding movement between said one and said other of said two hollow-cylindrical members.

9. The two-dimensional position detecting device according to claim 4, wherein said adjuster comprises two hollow-cylindrical members which are engaged with each other via male and female helicoidal threads,

wherein one of said two hollow-cylindrical members is fixed to said two-dimensional position sensor and the other of said two hollow-cylindrical members supports said imaging lens;

and

wherein a position of said imaging lens in the optical axis direction thereof is finely adjusted via a relative rotational movement between said one and said other of said two hollow-cylindrical members.