Camera having an autofocusing system

• US 8,169,530 B2
• Filed: 06/09/2008
• Issued: 05/01/2012
• Est. Priority Date: 06/19/2007
• Status: Active Grant

• Current Assignee: PENTAX RICOH IMAGING COMPANY, LTD.
• Original Assignee: Pentax Ricoh Imaging Americas Corporation (Ricoh Company Limited)
• Inventors: Nakahara, Naoto
• Primary Examiner(s): NGUYEN, LUONG TRUNG
• Application Number:
  US12/135,429
• Publication Number:
  US 20080316325A1
• Time in Patent Office: 1,422 Days
• Field of Search: None
• US Class Current: 348/345
• CPC Class Codes: G06V 40/166 using acquisition arrangements
• CPC Class Codes: H04N 23/61 based on recognised objects
• CPC Class Codes: H04N 23/611 where the recognised objects include parts of the human body
• CPC Class Codes: H04N 23/635 Region indicators; Field of view indicators
• 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 23/675 comprising setting of focusing regions

Abstract

An autofocus camera having a face recognition function, includes a photographing optical system including a focusing lens group; an image pickup device; an autofocusing system which performs a focus search process, and further performs a focusing operation in which the focusing lens group is moved to an in-focus position that is detected by the focus search process; a switch which activates the autofocusing system; a face recognition device for recognizing a face image based on object images; and a controller which makes the autofocusing system set the focus detection area on a face recognition area at which the face image is recognized and makes the autofocusing system perform the focus search process and the focusing operation on the focus detection area regardless of whether the switch is turned ON when the face recognition device recognizes the face image.

Claims

1. An autofocus camera having a face recognition function, comprising:

a photographing optical system including a focusing lens group movable along an optical axis;

an image pickup device;

an autofocusing system which performs a focus search process in which said image pickup device is activated to capture an object image at each of a plurality of different positions of said focusing lens group in an optical axis direction while said focusing lens group is moved along said optical axis to detect a position of said focusing lens group in the optical axis direction as an in-focus position based on object images obtained at said plurality of different positions of said focusing lens group in at least one focus detection area, and further performs a focusing operation in which said focusing lens group is moved to said in-focus position that is detected by said focus search process;

an autofocus switch which activates said autofocusing system upon said autofocus switch being turned ON;

a face recognition device for recognizing a face image based on the object images; and

a controller which controls said autofocusing system to set said focus at said at least one detection area on a face recognition area at which said face image is recognized by said face recognition device and controls said autofocusing system to perform said focus search process and said focusing operation on said at least one focus detection area regardless of whether said autofocus switch is turned ON, upon one of a lapse of a predetermined period of time after said face recognition device recognizes said face image and said face recognition device consecutively recognizes said face image a predetermined number of times, when said face recognition device recognizes said face image.

2. The autofocus camera according to claim 1, further comprising a portrait mode as one of plural selectable exposure modes of said autofocus camera,

wherein, after said portrait mode is selected, said controller controls said autofocusing system to set said focus detection area on said face recognition area and controls said autofocusing system to perform said focus search process and said focusing operation on said focus detection area regardless of whether said autofocus switch is turned ON upon one of a lapse of a predetermined period of time after said face recognition device recognizes said face image and said face recognition device consecutively recognizing said face image a predetermined number of times.

3. The autofocus camera according to claim 1, wherein said controller limits a range of movement of said focusing lens group in said focus search process from one to the other of a near extremity and a far extremity to a narrow range including a current position of said focusing lens group, upon said autofocus switch being turned ON after said autofocusing system performs said focus search process and said focusing operation, following recognition of said face image by said face recognition device.

4. The autofocus camera according to claim 3, wherein said controller does not limit said range of movement of said focusing lens group in said focus search process to said narrow range when said autofocusing system performs said focus search process and said focusing operation following said recognition of said face image by said face recognition device.

5. The autofocus camera according to claim 3, wherein, when said focusing lens group has not been previously moved to said in-focus position when said autofocus switch is turned ON, said controller does not limit said range of movement of said focusing lens group in said focus search process to said narrow range.

6. The autofocus camera according to claim 3, wherein, when said face recognition device has not previously recognized said face image when said autofocus switch is turned ON, said controller does not limit said range of movement of said focusing lens group in said focus search process to said narrow range.

7. The autofocus camera according to claim 3, further comprising a memory in which image data on said object image that is captured by said image pickup device is stored,

wherein said controller stores said image data in said memory after said autofocusing system moves said focusing lens group to said in-focus position following said recognition of said face image by said face recognition device, and

wherein, upon said autofocus switch being turned ON afterwards, said controller compares said image data currently captured by said image pickup device with said image data stored in said memory and does not limit said range of movement of said focusing lens group in said focus search process to said narrow range if a degree of matching between said current image data and said image data stored in said memory is lower than a predetermined degree.

8. The autofocus camera according to claim 7, wherein said image data, which is stored in said memory, comprises the pattern of an entire image based on said image data, and wherein said controller compares said pattern of said entire image based on said image data currently captured by said image pickup device with said pattern of said entire image stored in said memory.

9. The autofocus camera according to claim 3, wherein said controller does not limit said range of movement of said focusing lens group in said focus search process to said narrow range if a number of face images recognized by said face recognition device is unequal to a number of face images recognized before said autofocus switch is turned ON, when said switch is turned ON.

10. The autofocus camera according to claim 3, wherein said controller does not limit said range of movement of said focusing lens group in said focus search process to said narrow range if a difference between a current object brightness and an object brightness at a last previous operation of said autofocusing system is greater than a predetermined value when said autofocus switch is operated.

11. The autofocus camera according to claim 3, wherein said controller does not limit said range of movement of said focusing lens group in said focus search process to said narrow range if a central position of said face image recognized by said face recognition device upon said autofocus switch being turned ON is within a predetermined range with a center thereof coincident with a central position of a current face image recognized by said face recognition device.

12. The autofocus camera according to claim 1, further comprising a second switch which is turned ON after said autofocus switch is turned ON,

wherein, upon said second switch being turned ON, said image pickup device is activated to capture said object image at each of said plurality of different positions of said focusing lens group, and the captured image data on said object images is stored in an image memory.

13. The autofocus camera according to claim 1, wherein said autofocus switch is turned ON upon a release button of said autofocus camera being depressed half way.

14. The autofocus camera according to claim 12, wherein said autofocus switch and said second switch are turned ON upon a release button of said autofocus camera being half way depressed and fully depressed, respectively.

15. The autofocus camera according to claim 1, wherein said focusing lens group is moved along said optical axis from one to the other of a near extremity and a far extremity in said focus search process.

16. The autofocus camera according to claim 1, further comprising a power switch.

17. The autofocus camera according to claim 1, further comprising a memory in which image data regarding said object image that is captured by said image pickup device is stored, said controller storing said image data in said memory after said autofocusing system moves said focusing lens group to said in-focus position following recognition of said face image by said face recognition device.

18. The autofocus camera according to claim 1, said focusing lens group being moved along the optical axis, from one to the other of a near extremity and a far extremity during said focus search process, and being movable along the optical axis within a sub-range less than from one to the other of the near extremity and the far extremity in response to the satisfaction of a predetermined condition.

19. The autofocus camera according to claim 1, further including a selectable portrait mode, said face recognition device being operated to recognize the face image when said autofocus camera is in the portrait mode.

20. An autofocus camera having a face recognition function, comprising:

a photographing optical system including a focusing lens group movable along an optical axis;

an image pickup device;

an autofocusing system which performs a focus search process in which said image pickup device is activated to capture an object image at each of a plurality of different positions of said focusing lens group in an optical axis direction while said focusing lens group is moved along said optical axis to detect a position of said focusing lens group in the optical axis direction as an in-focus position based on object images obtained at said plurality of different positions of said focusing lens group in at least one focus detection area, and further performs a focusing operation in which said focusing lens group is moved to said in-focus position that is detected by said focus search process;

an autofocus switch which activates said autofocusing system upon said autofocus switch being turned ON;

a face recognition device for recognizing a face image based on the object images; and

a controller which controls said autofocusing system to set said focus at said at least one detection area on a face recognition area at which said face image is recognized by said face recognition device and controls said autofocusing system to perform said focus search process and said focusing operation on said at least one focus detection area regardless of whether said autofocus switch is turned ON, and limits a range of movement of said focusing lens group in said focus search process from one to the other of a near extremity and a far extremity to a narrow range including a current position of said focusing lens group, upon said autofocus switch being turned ON after said autofocusing system performs said focus search process and said focusing operation, following recognition of said face image by said face recognition device.