Imaging apparatus, control method thereof, program, and recording medium

Patent metadata

Field	Value
Publication number	US-10116858-B2
Application number	US-201715703079-A
Country	US
Kind code	B2
Filing date	Sep 13, 2017
Priority date	Sep 20, 2016
Publication date	Oct 30, 2018
Grant date	Oct 30, 2018

Abstract

At least one embodiment of an imaging apparatus has: an imaging plane capable of being curved; an evaluation unit that determines an evaluation value indicating a degree of in-focus of an image signal from the imaging element; an adjustment unit adjusting a position of the focus adjustment lens to a position with the highest evaluation value; and a control unit that controls the curvature of the imaging plane for correcting an image plane curve in the optical system and for bringing the image signal into focus. When the adjustment unit adjusts the position of the focus adjustment lens to an end portion of the movable area, the curvature of the imaging plane is controlled for bringing the image signal into focus on a priority basis.

First claim

What is claimed is:

1. An imaging apparatus comprising:
an optical system that includes a focus adjustment lens that operates to move forward and backward in an optical axis direction in a predetermined movable area;
an imaging element that has an imaging plane capable of being curved and that captures an image of a subject formed via the optical system;
an evaluation unit that determines an evaluation value indicating a degree of in-focus of an image signal output from the imaging element based on the image signal;
an adjustment unit that adjusts, based on the evaluation value, a position of the focus adjustment lens to, among positions in the predetermined movable area, a position with the highest evaluation value; and
a control unit that performs control of the curvature of the imaging plane for correcting an image plane curve in the optical system and that performs control of the curvature of the imaging plane for bringing the image signal into focus, wherein
in a case where the adjustment unit adjusts the position of the focus adjustment lens to an end portion of the predetermined movable area, the control unit performs the control of the curvature of the imaging plane for bringing the image signal into focus on a priority basis.

2. The imaging apparatus according to claim 1 , wherein, in a case where the adjustment unit adjusts the position of the focus adjustment lens to the end portion of the predetermined movable area, the control unit controls the curvature of the imaging plane for obtaining the degree of in-focus higher in the evaluation value than the degree of in-focus with the curvature of the imaging plane for correcting the image plane curve.

3. The imaging apparatus according to claim 2 , wherein the control unit controls the curvature of the imaging plane to, among possible curvatures of the imaging plane, change the curvature of the imaging plane to the curvature with the higher evaluation value.

4. The imaging apparatus according to claim 1 , wherein, in a case where the adjustment unit does not adjust the position of the focus adjustment lens to the end portion of the predetermined movable area, the control unit performs the control of the curvature of the imaging plane for correcting the image plane curve in the optical system on a priority basis.

5. The imaging apparatus according to claim 1 , further comprising an operation unit that accepts a user operation for starting the adjustment of the focus adjustment lens by the adjustment unit, wherein
when the adjustment unit adjusts the position of the focus adjustment lens to the end portion of the predetermined movable area and the user operation on the operation unit lasts beyond a predetermined threshold, the control unit performs the control of the curvature of the imaging plane for bringing the image signal into focus on a priority basis.

6. The imaging apparatus according to claim 1 , further comprising an operation unit that accepts a user operation for starting or ending the adjustment of the focus adjustment lens by the adjustment unit, wherein
in a case where the adjustment unit adjusts the position of the focus adjustment lens to the end portion of the predetermined movable area and the operation unit accepts a predetermined series of user operations, the control unit performs the control of the curvature of the imaging plane for bringing the image signal into focus on a priority basis, and
the predetermined series of user operations includes operations for starting the adjustment of the focus adjustment lens, then ending the adjustment, and then starting the adjustment of the focus adjustment lens that lasts beyond a predetermined threshold.

7. The imaging apparatus according to claim 1 , further comprising a setting unit that sets an operation mode of the imaging apparatus to any of a plurality of operation modes including a predetermined mode, wherein
in a case where the adjustment unit adjusts the position of the focus adjustment lens to the end portion of the predetermined movable area and the operation mode is the predetermined mode, the control unit performs the control of the curvature of the imaging plane for bringing the image signal into focus on a priority basis.

8. The imaging apparatus according to claim 7 , wherein the predetermined mode is an operation mode for enabling an operation for changing the curvature of the imaging plane and obtaining focus on the subject.

9. The imaging apparatus according to claim 1 , wherein
the optical system further includes a zoom lens that operates to move forward and backward in a predetermined movable area in an optical axis direction, and
the control unit controls the curvature of the imaging plane for correcting an image plane curve in the optical system according to the position of the zoom lens.

10. The imaging apparatus according to claim 1 , wherein the imaging element is configured to control the curvature of the imaging plane by magnetic force.

11. A control method of an imaging apparatus including: an optical system that includes a focus adjustment lens that operates to move forward and backward in an optical axis direction in a predetermined movable area; and an imaging element that has an imaging plane capable of being curved and that captures an image of a subject formed via the optical system, the control method comprising:
evaluating at which an evaluation unit determines an evaluation value indicating a degree of in-focus of an image signal output from the imaging element based on the image signal;
adjusting at which an adjustment unit adjusts, based on the evaluation value, a position of the focus adjustment lens to, among positions in the predetermined movable area, a position with the highest evaluation value; and
controlling at which the control unit performs control of the curvature of the imaging plane for correcting an image plane curve in the optical system and performs control of the curvature of the imaging plane for bringing the image signal into focus, wherein
at the controlling, when the adjustment unit adjusts the position of the focus adjustment lens to an end portion of the predetermined movable area, the control of the curvature of the imaging plane for bringing the image signal into focus is performed on a priority basis.

Assignees

• Canon Kk

Inventors

• Hatakeyama Koki

Classifications

• H04N23/673 Primary

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

• H04N23/62

  Control of parameters via user interfaces · CPC title

• H04N25/704

  Pixels specially adapted for focusing, e.g. phase difference pixel sets · CPC title

• H04N23/54

  Mounting of pick-up tubes, electronic image sensors, deviation or focusing coils · CPC title

• G02B7/282 Primary

  Autofocusing of zoom lenses · CPC title