Image capture apparatus and method of controlling the same

• US 9,167,172 B2
• Filed: 07/26/2012
• Issued: 10/20/2015
• Est. Priority Date: 09/01/2011
• Status: Active Grant

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Takaiwa, Kan
• Primary Examiner(s): OSINSKI, MICHAEL S
• Application Number:
  US13/558,893
• Publication Number:
  US 20130057740A1
• Time in Patent Office: 1,181 Days
• Field of Search: 348/222.1, 3482291-2301, 348234-238, 348294-324, 348345-357, 348362-368, 348370-371, 396 61- 70, 396155-206, 396213-262
• US Class Current: 1/1
• CPC Class Codes: H04N 23/672 based on the phase difference signals
• CPC Class Codes: H04N 23/74 by influencing the scene brightness using illuminating means
• CPC Class Codes: H04N 25/134 based on three different wavelength filter elements
• CPC Class Codes: H04N 25/583 with different integration times
• CPC Class Codes: H04N 25/704 Pixels specially adapted for focusing, e.g. phase difference pixel sets

Abstract

An image capture apparatus comprises an image sensor, an acquisition unit which acquires information concerning distances to objects in a plurality of areas in an image capturing area, and a control unit which controls a charge accumulation period for each of a plurality of segmented areas of the image sensor, wherein the plurality of areas for which information concerning distances to the objects are acquired by the acquisition unit respectively correspond to the plurality of segmented areas, and the control unit controls the charge accumulation periods for the respective segmented areas at the time of light emission by a light-emitting device based on the information concerning the distances to the objects in the corresponding areas.

Claims

1. An image capture apparatus comprising:

an image sensor; and

at least one control circuit to perform, acquiring respective information corresponding to distances to objects in a plurality of areas in an image capturing area based on signals which are read from a phase difference detecting member and

controlling respective charge accumulation periods for each of a plurality of segmented areas of said image sensor during a time of light emission by a light-emitting device,

wherein the plurality of areas in the image capturing area for which information corresponding to distances to the objects are acquired by said at least one control circuit respectively correspond to the plurality of segmented areas, and

wherein said at least one control circuit performs, controlling respective charge accumulation periods for each of the segmented areas corresponding to the plurality of areas in the image capturing area based on the respective information corresponding to the distances to the objects in the corresponding segmented areas.

2. The apparatus according to claim 1, wherein said at least one control circuit performs setting longer charge accumulation periods for each of segmented areas in accordance with longer distances to the objects based on the information corresponding to the distances to the objects in the corresponding areas in a plurality of areas in the image capturing area.

3. The apparatus according to claim 1, wherein said at least one control circuit performs setting a relatively longer charge accumulation period for a segmented area corresponding to an area of a plurality of areas in the image capturing area whose distance to an object based on the information corresponding to the distances to the objects is a first distance than a charge accumulation period for a segmented area corresponding to an area of a plurality of areas in the image capturing area whose distance to an object based on the information corresponding to the distances to the objects is a second distance shorter than the first distance.

4. The apparatus according to claim 1, wherein at least one control circuit performs controlling light emission for the light-emitting device with a substantially constant light emission intensity during charge accumulation for each of a plurality of segmented areas corresponding to a plurality of areas in the image capturing area in a predetermined interval.

5. The apparatus according to claim 4, wherein said at least one control circuit performs controlling charge accumulation periods for each of a plurality of segmented areas so as to start and finish charge accumulation in all of the segmented areas in an interval during which the light-emitting device performs light emission with a substantially constant light emission intensity.

6. The apparatus according to claim 1, wherein said at least one control circuit performs, acquiring information corresponding to distances to the objects for each of the plurality of areas in the image capturing area before pre-flash by the light-emitting device, and controlling charge accumulation periods for each of a plurality of segmented areas at the time of pre-flash by the light-emitting device based on the information corresponding to the distances to the objects which is acquired before pre-flash by the light-emitting device.

7. The apparatus according to claim 1, wherein the phase difference detecting member is pixels in said image sensor which is able to detect the phase difference.

8. The apparatus according to claim 1, wherein said at least one control circuit performs setting respective charge accumulation periods for each of a plurality of segmented areas to an equal time when distances to objects in all of a plurality of areas in the image capturing area are unknown.

9. The apparatus according to claim 1, wherein when distances to objects in some of a plurality of areas in the image capturing area are unknown, said at least one control circuit performs setting a charge accumulation period for a segmented area corresponding to an area whose distance to an object is unknown to a longest charge accumulation period of charge accumulation periods for segmented areas corresponding to areas whose distances to objects are known.

10. The apparatus according to claim 1, wherein when distances of some of a plurality of areas in the image capturing area to objects are longer than a predetermined distance, said at least one control circuit performs setting a charge accumulation period for a segmented area corresponding to an area whose distance to an object is longer than the predetermined distance to a longest charge accumulation period of charge accumulation periods for segmented areas corresponding to areas whose distances to objects are not longer than the predetermined distance.

11. The apparatus according to claim 6, wherein said at least one control circuit performs determining a light amount of main light emission by the light- emitting device based on a charge accumulation result obtained by said image sensor at the time of pre-flash by the light-emitting device.

21. The apparatus according to claim 1, wherein said at least one control circuit performs setting respectively different charge accumulation periods for each of segmented areas corresponding to an area of a plurality of areas in the image capturing area whose distance to an object based on the information corresponding the distances to an objects is a first distance and corresponding to an area of a plurality areas in the image capturing area whose distance to an object based on the information corresponding the distances to the objects is a second distance which is different from the first distance.

22. The apparatus according to claim 21, wherein said at least one control circuit performs controlling charge accumulation periods for each of segmented area corresponding to the first area and the second area so that a part of charge accumulation period corresponding to the first area and a part of charge accumulation period corresponding to the second area are overlapped.

23. The apparatus according to claim 1, wherein the information corresponding to distances to the objects is a distances from the apparatus to the objects.

24. The apparatus according to claim 1, wherein the information corresponding to distances to the objects is a defocus amount of the object image.

12. An image capture apparatus comprising:

an image sensor; and

at least one control circuit to perform, acquiring respective information corresponding to distances to objects in a plurality of areas in an image capturing area based on signals which are read from a phase difference detecting member and controlling respective sensitivities for each of a plurality of segmented areas of said image sensor during a time of light emission by a light-emitting device,

wherein the plurality of areas in the image capturing area for which information corresponding to distances to the objects are acquired by said at least one control circuit respectively correspond to the plurality of segmented areas, and

wherein said at least one control circuit performs controlling respective sensitivities for each of the segmented areas corresponding to the plurality of areas in the image capturing area based on the respective information corresponding to the distances to the objects in the corresponding segmented areas.

13. The apparatus according to claim 12, wherein said at least one control circuit performs setting higher sensitivities for each of segmented areas in accordance with longer distances to the objects based on the information corresponding to the distances to the objects in the corresponding areas in a plurality of areas in the image capturing area.

14. The apparatus according to claim 12, wherein said at least one control circuit performs controlling respective sensitivities for each of a plurality of segmented areas at the time of light emission by the light-emitting device with a substantially constant light emission intensity in a predetermined interval based on the information corresponding to distances to the objects.

15. The apparatus according to claim 12, wherein said at least one control circuit performs acquiring information corresponding to distances to the objects for each of a plurality of areas in the image capturing area before pre-flash by the light-emitting device, and controlling sensitivities for each of a plurality of segmented areas at the time of pre-flash by the light-emitting device based on the information corresponding the distances to the objects which is acquired before pre-flash by the light-emitting device.

16. The apparatus according to claim 12, wherein the phase difference member is pixels in said image sensor which is able to detect the phase difference.

17. The apparatus according to claim 12, wherein said at least one control circuit performs setting respective sensitivities for each of a plurality of segmented areas to an equal sensitivity when distances to objects in all of a plurality of areas in the image capturing area are unknown.

18. The apparatus according to claim 12, wherein when distances to objects in some of a plurality of areas in the image capturing area are unknown, said at least one control circuit performs setting a sensitivity for a segmented area corresponding to an area whose distance to an object is unknown to a highest sensitivity of sensitivities for segmented areas corresponding to areas whose distances to objects are known.

25. The apparatus according to claim 12, wherein said at least one control circuit performs setting respectively different sensitivities for each of segmented areas corresponding to an area of a plurality of areas in the image capturing area whose distance to an object based on the information corresponding to the distances to the objects is a first distance and corresponding to an area of a plurality of areas in the capturing area whose distance to an object based on the information corresponding to the distances to the objects is a second distance which is different from the first distance.

26. The apparatus according to claim 12, wherein the information corresponding to distances to the objects is a distance from the apparatus to the objects.

27. The apparatus according to claim 12, wherein the information corresponding to distances to the objects is a defocus amount of the object image.

19. A method of controlling an image capture apparatus having an image sensor, said method comprising:

acquiring respective information corresponding to distances to objects in a plurality of areas in an image capturing area based on signals which are read from a phase difference detecting member, and

controlling respective charge accumulation periods for each of a plurality of segmented areas of said image sensor during a time of light emission by a light-emitting device, and controlling respective charge accumulation periods for each of the segmented areas corresponding to the plurality of areas in the image capturing area based on the respective information corresponding to the distances to the objects in the corresponding segmented areas,

wherein the plurality of areas in the image capturing area for which information corresponding to distances to the objects which acquiring respectively correspond to the plurality of segmented areas.

20. A method of controlling an image capture apparatus having an image sensor, said method comprising:

acquiring respective information corresponding to distances to objects in a plurality of areas in an image capturing area based on signals which are read from a phase difference detecting member, and

controlling respective sensitivities for each of a plurality of segmented areas of said image sensor during a time of light emission by a light-emitting device, and controlling respective sensitivities for each of the segmented areas corresponding to the plurality of areas in the image capturing area based on the respective information corresponding to the distances to the objects in the corresponding segmented areas,

wherein the plurality of areas in the image capturing area for which information corresponding to distances to the objects which acquiring respectively correspond to the plurality of segmented areas.

28. An image capture apparatus comprising:

an image sensor; and

at least one control circuit to perform, acquiring respective information corresponding to distances to objects in a plurality of areas based on signals which are read from a phase difference detecting member and

controlling at least one of respective charge accumulation periods and respective sensitivities for each of a plurality of areas of said image sensor,

wherein the plurality of areas for which information corresponding to distances to the objects are acquired by said acquisition unit respectively correspond to the plurality of areas of said image sensor controlled by said at least one control circuit, and

wherein said at least one control circuit performs controlling at least one of respective charge accumulation periods and respective sensitivities for each of the plurality of areas of said image sensor corresponding to the plurality of areas based on the respective information corresponding to the distances to the objects in the corresponding plurality of areas.

29. The apparatus according to claim 28, wherein said at least one control circuit performs controlling at least one of respective charge accumulation periods and respective sensitivities for each of the plurality of areas of said image sensor during a time of light emission by a light-emitting device.

30. The apparatus according to claim 28, wherein said at least one control circuit performs acquiring respective information corresponding to distances to objects in the plurality of areas in an image capturing area.

31. A method of controlling an image capture apparatus having an image sensor, said method comprising:

acquiring respective information corresponding to distances to objects in a plurality of areas based on signals which are read from a phase difference detecting member, and

controlling at least one of respective charge accumulation periods and respective sensitivities for each of a plurality of areas of said image sensor, and

controlling at least one of respective charge accumulation periods and respective sensitivities for each of the plurality areas of said image sensor corresponding to the plurality of areas based on the respective information corresponding to the distances to the objects in the corresponding plurality of areas,

wherein the plurality of areas for which information corresponding to distances to the objects which acquiring respectively correspond to the plurality of areas of said image sensor.