Imaging apparatus having an apodization filter and capable of selecting first and second program diagrams

Patent metadata

Field	Value
Publication number	US-10122934-B2
Application number	US-201715716081-A
Country	US
Kind code	B2
Filing date	Sep 26, 2017
Priority date	Mar 27, 2015
Publication date	Nov 6, 2018
Grant date	Nov 6, 2018

Abstract

A subject information acquisition section acquires a subject distance difference, which is distance difference between a main subject and a subject farthest from the main subject, on the basis of an imaging signal sent from an imaging element. A program diagram storage section stores a first program diagram where an aperture value is fixed at an open aperture value at a first amount of exposure EV1 or less, and stores a second program diagram where an aperture value is fixed at an open aperture value at a second amount of exposure EV2, which is greater than the first amount of exposure EV1, or less. An imaging exposure determination section selects the second program diagram in a case where an APD filter is disposed on the optical path and a case where the subject distance difference is equal to or greater than a threshold value and there is an imaged scene in which a blurred image tends to occur, and selects the first program diagram in a case where the subject distance difference is less than the threshold value and there is an imaged scene in which a blurred image is hard to occur.

First claim

What is claimed is:

1. An imaging apparatus comprising:
an imaging element that photoelectrically converts incident light so as to output an imaging signal;
a stop that adjusts a light amount of the incident light;
an apodization filter that is disposed on an optical path of the incident light; and
an electric signal processing device configured for:
performing photometry based on the imaging signal;

storing a first program diagram in which an aperture value is fixed at an open aperture value in a case where an amount of exposure is equal to or less than a first amount of exposure, and a second program diagram in which an aperture value is fixed at an open aperture value in a case where the amount of exposure is equal to or less than a second amount of exposure, which is greater than the first amount of exposure;
acquiring subject information based on the imaging signal; and
selecting the second program diagram in a case where the apodization filter is disposed on the optical path and the subject information satisfies a first condition;
selecting the first program diagram in a case where the apodization filter is not disposed on the optical path and in a case where the apodization filter is disposed on the optical path and the subject information does not satisfy the first condition; and
determining one group of an imaging aperture value and an imaging shutter speed based on an amount of imaging exposure which is calculated from a photometric value obtained by the performing photometry.

2. The imaging apparatus according to claim 1 ,
wherein the electric signal processing device acquires, as the subject information, a subject distance difference between a main subject and a subject farthest from the main subject, and
wherein the electric signal processing device sets the first condition as a condition in which the subject distance difference is equal to or greater than a threshold value.

3. The imaging apparatus according to claim 2 ,
wherein in addition to the subject distance difference, the electric signal processing device acquires, as the subject information, a main subject distance which is a subject distance up to a main subject, and
wherein the electric signal processing device sets the first condition as a condition in which the main subject distance is less than a specific distance and the subject distance difference is equal to or greater than a threshold value.

4. The imaging apparatus according to claim 3 , wherein the electric signal processing device divides an imaging range of the imaging element into a plurality of blocks, calculates a subject distance for each of the blocks, and calculates the subject distance difference and the main subject distance from the subject distance of each of the blocks.

5. The imaging apparatus according to claim 1 , wherein a shutter speed corresponding to the second amount of exposure in the second program diagram is faster than a shutter speed corresponding to the first amount of exposure in the first program diagram.

6. The imaging apparatus according to claim 5 , further comprising a mechanical shutter,
wherein the shutter speed corresponding to the second amount of exposure in the second program diagram is a limit speed on a high speed side of the mechanical shutter.

7. The imaging apparatus according to claim 6 ,
wherein the imaging element has an electronic shutter function capable of making an imaging shutter speed faster than the limit speed,
wherein the electric signal processing device stores a third program diagram in which an aperture value is fixed at an open aperture value in a case where the amount of exposure is equal to or less than a third amount of exposure which is greater than the second amount of exposure, and
wherein the electric signal processing device selects the third program diagram in a case where the first condition is satisfied and a second condition different from the first condition is satisfied, and selects the second program diagram in a case where the first condition is satisfied and the second condition is not satisfied.

8. The imaging apparatus according to claim 7 , wherein the electric signal processing device detects an amount of movement of the main subject based on the imaging signal of a plurality of frames,
wherein the electronic shutter function is a rolling shutter system, and
wherein the electric signal processing device sets the second condition as a condition in which the amount of movement is equal to or less than a specific value.

9. The imaging apparatus according to claim 7 , wherein the electric signal processing device detects whether or not flickering occurs by calculating a change in luminance value from the imaging signal of the plurality of frames,
wherein the electric signal processing device sets the second condition as a condition in which the flickering is not detected.

10. The imaging apparatus according to claim 2 ,
wherein in addition to the subject distance difference, the electric signal processing device acquires, as the subject information, a size of a face of a subject in a case where whether or not the face is present is detected based on the imaging signal and then the face is present, and
wherein the electric signal processing device sets the first condition as a condition in which the main subject distance is less than a specific distance and the size of the face is equal to or greater than a threshold value in the case where the face is detected.

11. An imaging apparatus body in which a first lens barrel having an apodization filter and a second lens barrel having no apodization filter are mountable, the imaging apparatus body comprising:
an imaging element that photoelectrically converts incident light so as to output an imaging signal;
a stop that adjusts a light amount of the incident light;
an electric signal processing device configured for:
performing photometry based on the imaging signal;
storing a first program diagram in which an aperture value is fixed at an open aperture value in a case where an amount of exposure is equal to or less than a first amount of exposure, and a second program diagram in which an aperture value is fixed at an open aperture value in a case where the amount of exposure is equal to or less than a second amount of exposure which is greater than the first amount of exposure;

acquiring subject information based on the imaging signal;
selecting the second program diagram in a case where the first lens barrel is mounted and the subject information satisfies a first condition;
selecting the first program diagram in a case where the second lens barrel is mounted and in a case where the first lens barrel is mounted and the subject information does not satisfy the first condition; and
determining one group of an imaging aperture value and an imaging shutter speed based on an amount of imaging exposure which is calculated from a photometric value obtained by the performing photometry.

12. A method of controlling an imaging apparatus including an imaging element that photoelectrically converts incident light so as to output an imaging signal, a stop that adjusts a light amount of the incident light, an apodization filter that is disposed on an optical path of the incident light, an electric signal processing device configured for performing photometry based on the imaging signal, storing a first program diagram in which an aperture value is fixed at an open aperture value in a case where an amount of exposure is equal to or less than a first amount of exposure, and a second program diagram in which an aperture value is fixed at an open aperture value in a case where the amount of exposure

Assignees

• Fujifilm Corp

Inventors

• Uchida Akihiro

Classifications

• H04N23/611

  where the recognised objects include parts of the human body · CPC title

• H04N23/672

  based on the phase difference signals · CPC title

• H04N23/663

  for controlling interchangeable camera parts based on electronic image sensor signals · CPC title

• H04N23/75

  by influencing optical camera components · CPC title

• H04N23/72 Primary

  Combination of two or more compensation controls · CPC title