Imager with auto focus functionality

• US 7,962,025 B2
• Filed: 02/18/2010
• Issued: 06/14/2011
• Est. Priority Date: 02/20/2009
• Status: Expired due to Fees

• Current Assignee: PENTAX RICOH IMAGING COMPANY, LTD.
• Original Assignee: Hoya Corporation
• Inventors: Yamamoto, Yasuhiro
• Primary Examiner(s): Perkey; W. B.
• Assistant Examiner(s): REISNER, NOAM S
• Application Number:
  US12/707,856
• Publication Number:
  US 20100215352A1
• Time in Patent Office: 481 Days
• Field of Search: 396/55, 348/208.12
• US Class Current: 396/55
• CPC Class Codes: G03B 17/00 Details of cameras or camera bodies; Accessories therefor lens hoods or caps G03B11/04
• CPC Class Codes: H04N 23/673 based on contrast or high frequency components of image signals, e.g. hill climbing method
• 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

An imager comprising is provided having an image-capturing device, a display, and a view angle controller. The first in-focus detector is movable with respect to a stationary platform, and detects whether a subject image is in focus of an image sensor. The shake detector detects a shake transmitted to the first in-focus detector. The first driver repositions the first in-focus detector with respect to the stationary platform according to a shake detected by the shake detector. The first in-focus detector provided on an in-focus light path is different from a photographing light path on which light is directed to the image sensor, and detects whether a subject image is in focus using incoming light along the in-focus light path.

Claims

1. An imager comprising:

a first in-focus detector that is movable with respect to a stationary platform, and detects whether a subject image is in focus of an image sensor;

a shake detector that detects a shake transmitted to said first in-focus detector; and

a first driver that repositions said first in-focus detector with respect to the stationary platform according to a shake detected by said shake detector;

said first in-focus detector provided on an in-focus light path that is different from a photographing light path on which light is directed to the image sensor, and detects whether a subject image is in focus using incoming light along the in-focus light path.

2. The imager according to claim 1, wherein said first in-focus detector comprises first and second separator lenses that separate light passing along the in-focus light path, and a light detector that is illuminated by light passing through the first and second separator lenses, and the light detector determines whether a subject image is in focus on the image sensor on the basis of whether the distance between a position illuminated by light passing through the first separator lens and a position illuminated by light passing through the second separator lens is greater or less than a predetermined distance.

3. The imager according to claim 1, wherein the image sensor is movable with respect to the stationary platform, said shake detector detects a shake transmitted to the image sensor, and the imager further comprises a second driver that moves the image sensor relative to the stationary platform so as to cancel out the relative change in position of a subject caused by shaking detected by said shake detector.

4. The imager according to claim 3, wherein said second driver drives the image sensor in two directions on an imaging surface of the image sensor.

5. The imager according to claim 3, wherein the relative position of the image sensor with respect to an optical axis of the photographing light path is the same as the relative position of said first in-focus detector with respect to an optical axis of the in-focus light path, and the velocity of the image sensor moving toward the stationary platform is the same as the velocity of said first in-focus detector moving toward the stationary platform.

6. The imager according to claim 3, wherein said first driver is driven by said second driver.

7. The imager according to claim 6, wherein said first driver comprises a flexible plate that is driven by said second driver and a straight bar that changes the drive direction of the flexible plate by 90 degrees, the flexible plate has first and second regions and is driven by said second driver so as to reciprocate along the extending direction of the straight bar or along the orthogonal direction to the extended direction of the straight bar, said first in-focus detector is provided in the first region, and said second in-focus detector is provided in the second region.

8. The imager according to claim 6, further comprising a light direction changer that directs incoming light from an imaging optical system to either the photographing light path or the in-focus light path having the light axis parallel to the light axis of the photographing light path, said first driver comprises a plate driven by said second driver, and said in-focus detector and the imaging sensor are provided on the plate.

9. The imager according to claim 3, further comprising a second in-focus detector that detects whether a subject image is in focus on an image sensor using incoming light that is incident on the image sensor, and said second in-focus detector detects whether a subject image is in focus on an image sensor using a subject image in an in-focus detection area provided on the imaging surface of the image sensor.

10. The imager according to claim 1, further comprising a second in-focus detector that detects whether a subject image is in focus on an image sensor using incoming light that is incident on the image sensor.

11. The imager according to claim 10, wherein said second in-focus detector detects whether a subject image is in focus on an image sensor using a subject image in an in-focus detection area provided on the imaging surface of the image sensor.

12. The imager according to claim 11, wherein said shake detector detects a shake transmitted to the image sensor, and the imager further comprises a detection area changer that changes the position of the in-focus detecting area on the imaging surface so as to cancel out the relative change in position of a subject caused by the shake detected by said shake detector.

13. The imager according to claim 11, wherein the relative position of the in-focus detection area with respect to an optical axis of the photographing light path is the same as the relative position of said first in-focus detector with respect to an optical axis of the in-focus light path, and the velocity of the in-focus detection area moving on the imaging surface is the same as the velocity of the first in-focus detector moving toward the stationary platform.

14. The imager according to claim 1, further comprising a light direction changer that directs light from an imaging optical system onto either the photographing light path or the in-focus light path.

15. The imager according to claim 1, wherein said first driver drives said first in-focus detector in two directions on the surface that is orthogonal to the axis of the in-focus light path.

16. The imager according to claim 1, wherein said shake detector comprises an angular rate sensor.

17. The imager according to claim 1, wherein said shake detector detects a shake using a subject image incident on the imaging sensor.