Control apparatus, image pickup apparatus, image pickup system, lens apparatus, control method, and non-transitory computer-readable storage medium

Patent metadata

Field	Value
Publication number	US-9918003-B2
Application number	US-201514927651-A
Country	US
Kind code	B2
Filing date	Oct 30, 2015
Priority date	Nov 10, 2014
Publication date	Mar 13, 2018
Grant date	Mar 13, 2018

Abstract

A control apparatus includes a focus detector configured to perform focus detection based on an image signal obtained via a first optical system, the first optical system having a shallowest depth of field in a plurality of optical systems having focal lengths different from each other, and a controller configured to perform focus control of the plurality of optical systems based on an output signal from the focus detector.

First claim

What is claimed is:

1. A control apparatus comprising:
a focus detector configured to perform focus detection based on an image signal obtained via a first imaging optical system, the first imaging optical system having a shallowest depth of field in a plurality of imaging optical systems having focal lengths different from each other; and
a controller configured to:
obtain an output signal from the focus detector, the output signal being generated based on the image signal obtained via the first imaging optical system;
determine position information of a first focus unit of the first imaging optical system; and
perform focus control of a second imaging optical system, different from the first imaging optical system, of the plurality of imaging optical systems based on position information of a second focus unit of the second imaging optical system, the position information of the second focus unit being determined based on the determined position information of the first focus unit.

2. The control apparatus according to claim 1 , further comprising a calculator configured to calculate a movement position of the second focus unit,
wherein:
the controller is configured to perform the focus control by moving the first focus unit based on the output signal from the focus detector, and
the calculator is configured to calculate the movement position of the second focus unit based on a position of the first focus unit.

3. The control apparatus according to claim 1 , wherein the controller is configured to perform the focus control by integrally moving a plurality of focus units of the plurality of imaging optical systems by an identical moving amount based on the output signal from the focus detector.

4. The control apparatus according to claim 1 , further comprising:
an acquirer configured to acquire image capturing condition information; and
a determiner configured to determine the first imaging optical system based on the image capturing condition information.

5. The control apparatus according to claim 4 , wherein:
the acquirer is configured to acquire, as the image capturing condition information, information relating to the plurality of imaging optical systems, focal lengths of the imaging optical systems, and F numbers of the imaging optical systems, and
the determiner is configured to determine the first imaging optical system satisfying a conditional expression below:

f
i
2

Fno
i

≤

f
1
2

Fno
1

,

where f 1 is a focal length of the first imaging optical system, Fno 1 is an F number of the first imaging optical system, f i is a focal length of one of the imaging optical systems, and Fno i is an F number of the one of the imaging optical systems.

6. The control apparatus according to claim 1 , wherein the focus detector is configured to perform the focus detection by a contrast detection method.

7. The control apparatus according to claim 1 , wherein the focus detector is configured to perform the focus detection by a phase-difference detection method.

8. The control apparatus according to claim 1 ,
wherein the focus detector includes:
a first focus detector configured to perform focus detection by a phase-difference detection method, and
a second focus detector configured to perform focus detection by a contrast detection method, and

wherein the controller is configured to:
perform first focus control based on a first output signal from the first focus detector, and
perform second focus control based on a second output signal from the second focus detector after the first focus control.

9. The control apparatus according to claim 4 , further comprising:
a region determiner configured to determine a region in which the focus detection is to be performed; and
an inclusion determiner configured to determine whether the region determined by the region determiner is included in an image pickup region for each of the plurality of imaging optical systems,
wherein the determiner is configured to determine the first imaging optical system based on a determination result of the inclusion determiner.

10. An image pickup apparatus comprising:
an image pickup element configured to photoelectrically convert an optical image formed via at least one of a plurality of imaging optical systems, the plurality of imaging optical systems having focal lengths different from each other;
a focus detector configured to perform focus detection based on an image signal obtained via a first imaging optical system, the first imaging optical system having a shallowest depth of field in the plurality of imaging optical systems; and
a controller configured to:
obtain an output signal from the focus detector, the output signal being generated based on the image signal obtained via the first imaging optical system;
determine position information of a first focus unit of the first imaging optical system; and
perform focus control of a second imaging optical system, different from the first imaging optical system, of the plurality of imaging optical systems based on position information of a second focus unit of the second imaging optical system, the position information of the second focus unit being determined based on the determined position information of the first focus unit.

11. The image pickup apparatus according to claim 10 , wherein the image pickup element includes a plurality of image pickup regions corresponding to the respective imaging optical systems.

12. An image pickup system comprising:
a plurality of imaging optical systems, wherein at least one imaging optical system of the plurality of imaging optical systems has a different focal length from another imaging optical system of the plurality of imaging optical systems;
an image pickup element configured to photoelectrically convert an optical image formed via at least one of the plurality of imaging optical systems;
a focus detector configured to perform focus detection based on an image signal obtained via a first imaging optical system, the first imaging optical system having a shallowest depth of field in the plurality of imaging optical systems; and
a controller configured to:
obtain an output signal from the focus detector, the output signal being generated based on the image signal obtained via the first imaging optical system;
determine position information of a first focus unit of the first imaging optical system; and
perform focus control of a second imaging optical system, different from the first imaging optical system, of the plurality of imaging optical systems based on position information of a second focus unit of the second imaging optical system, the position information of the second focus unit being determined based on the determined position information of the first focus unit.

13. The image pickup system according to claim 12 , wherein the plurality of optical systems includes at least one imaging optical system that has an identical focal length as another imaging optical system of the plurality of imaging optical systems.

14.

Assignees

• Canon Kk

Inventors

• Inoue Chiaki

Classifications

• H04N23/673 Primary

  based on contrast or high frequency components of image signals, e.g. hill climbing method · CPC title

• H04N23/672

  based on the phase difference signals · CPC title

• G02B15/14

  by axial movement of one or more lenses or groups of lenses relative to the image plane for continuously varying the equivalent focal length of the objective · CPC title

• G02B7/365 Primary

  by analysis of the spatial frequency components of the image · CPC title

• G02B27/0075

  with means for altering, e.g. increasing, the depth of field or depth of focus · CPC title