IMAGE CAPTURE APPARATUS AND METHOD OF CONTROLLING THE SAME

• US 20130057740A1
• Filed: 07/26/2012
• Published: 03/07/2013
• 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
• Granted Patent: US 9,167,172 B2
• Time in Patent Office: Days
• US Class Current: 348/297
• 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;

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 said image sensor,

wherein the plurality of areas for which information concerning distances to the objects are acquired by said acquisition unit respectively correspond to the plurality of segmented areas, and

said 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.

2. The apparatus according to claim 1, wherein said control unit sets longer charge accumulation periods for the segmented areas in accordance with longer distances to the objects based on the information concerning the distances to the objects in the corresponding areas.

3. The apparatus according to claim 1, wherein said control unit sets a relatively longer charge accumulation period for a segmented area corresponding to an area whose distance to an object based on the information concerning the distances to the objects is a first distance than a charge accumulation period for a segmented area corresponding to an area whose distance to an object based on the information concerning the distances to the objects is a second distance shorter than the first distance.

4. The apparatus according to claim 1, wherein said control unit controls charge accumulation periods for the respective 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 concerning the distances to the objects which is acquired by said acquisition unit.

5. The apparatus according to claim 4, wherein said control unit controls charge accumulation periods for the respective segmented areas so as to start and finish charge accumulation in 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 acquisition unit acquires information concerning distances to the objects before pre-flash by the light- emitting device, and

said control unit controls charge accumulation periods for the respective segmented areas at the time of pre-flash by the light-emitting device based on the information concerning the distances to the objects which is acquired by said acquisition unit before pre-flash by the light-emitting device.

7. The apparatus according to claim 1, wherein said image sensor is provided with a phase difference detecting pixel, and

said acquisition unit acquires information concerning distances to the objects which includes information based on an output from said phase difference detecting pixel.

8. The apparatus according to claim 1, wherein said control unit sets charge accumulation periods for the respective 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 control unit sets 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 control unit sets 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, further comprising a determination unit which determines 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.

12. An image capture apparatus comprising:

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 sensitivity for each of a plurality of segmented areas of said image sensor,

wherein the plurality of areas for which information concerning distances to the objects are acquired by said acquisition unit respectively correspond to the plurality of segmented areas, and

said control unit controls the sensitivities 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.

13. The apparatus according to claim 12, wherein said control unit sets higher sensitivities for the segmented areas in accordance with longer distances to the objects based on the information concerning the distances to the objects in the corresponding areas.

14. The apparatus according to claim 12, wherein said control unit controls sensitivities for the respective 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 concerning distances to the objects which is acquired by said acquisition unit.

15. The apparatus according to claim 12, wherein said acquisition unit acquires information concerning distances to the objects before pre-flash by the light-emitting device, and

said control unit controls sensitivities for the respective segmented areas at the time of pre-flash by the light-emitting device based on the information concerning the distances to the objects which is acquired by said acquisition unit before pre-flash by the light-emitting device.

16. The apparatus according to claim 12, wherein said image sensor is provided with a phase difference detecting pixel, and

said acquisition unit acquires information concerning distances to the objects which includes information based on an output from said phase difference detecting pixel.

17. The apparatus according to claim 12, wherein said control unit sets sensitivities for the respective 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 control unit sets 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.

19. A method of controlling an image capture apparatus having an image sensor, an acquisition unit which acquires information concerning distances to objects in a plurality of areas in an image capturing area, said method comprising:

a control step of controlling a charge accumulation period for each of a plurality of segmented areas of said image sensor,

wherein the plurality of areas for which information concerning distances to the objects are acquired by said acquisition unit respectively correspond to the plurality of segmented areas, and

said control step 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.

20. A method of controlling an image capture apparatus having an image sensor, an acquisition unit which acquires information concerning distances to objects in a plurality of areas in an image capturing area, said method comprising:

a control step of controlling a sensitivity for each of a plurality of segmented areas of said image sensor,

wherein the plurality of areas for which information concerning distances to the objects are acquired by said acquisition unit respectively correspond to the plurality of segmented areas, and

said control step controls the sensitivities 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.