Focus adjustment function of imaging device, focus adjustment function of imaging device main body, and focus adjustment method of imaging device
Provided are an imaging device, an imaging device main body, and a focusing control method of an imaging device capable of adjusting a focus with high accuracy by appropriately supporting the focus adjustment in a manual manner. An image sensor movement driver ( 220 ) that moves an image sensor ( 210 ) along an optical axis (L), and an image sensor movement controller ( 250 a ) that controls the movement of the image sensor ( 210 ) by controlling the image sensor movement driver ( 220 ) are provided. In a case where a subject is focused, the image sensor movement controller ( 250 a ) starts the tracking, and controls the movement of the image sensor ( 210 ) such that a focusing state is maintained based on a defocus amount detected by the phase difference AF processing unit ( 132 ).
1. An imaging device comprising:
an imaging lens that has a focus adjustment function for performing manual focusing;
an image sensor that images a subject via the imaging lens;
an image sensor movement driver that physically moves the image sensor along an optical axis; and
an image sensor movement controller, including processing circuitry, that controls the movement of the image sensor to start tracking the subject based on a detected defocus amount in a case where the subject is focused by manual focusing of the imaging lens,
wherein one of the following is implemented in the imaging device:
wherein the image sensor movement controller ends the tracking of the subject in a case where the image sensor reaches an end portion of a movable range, and moves the image sensor to a reference position,
wherein the image sensor movement controller ends the tracking of the subject in a case where the image sensor reaches an end portion of a movable range, and causes the image sensor to stand by at a position of the end portion until the subject is focused again,
wherein the image sensor movement controller determines that the subject is focused in a case where the detected defocus amount is continuously equal to or less than a threshold value for a predetermined time,
wherein the image sensor movement controller determines that the subject is focused in a case where the detected defocus amount is continuously equal to or less than a first threshold value for a predetermined time and a change amount of the detected defocus amount is continuously equal to or less than a second threshold value for a predetermined time, or
wherein the imaging device further comprises a tracking mode automatic switcher that turns on a tracking mode in a case where the subject is continued to be focused for a predetermined time, and the image sensor movement controller controls the movement of the image sensor to track the subject in a case where the tracking mode is turned on.
2. The imaging device according to claim 1 ,
wherein the image sensor movement controller moves the image sensor to the reference position by moving the image sensor at a moving speed corresponding to a change of the detected defocus amount.
3. The imaging device according to claim 2 ,
wherein the reference position of the image sensor is set at a flange back position defined by the imaging lens.
4. The imaging device according to claim 1 ,
wherein the detected defocus amount is based on outputs of a plurality of phase difference detection pixels formed on an imaging surface of the image sensor.
5. The imaging device according to claim 1 , further comprising:
a tracking mode manual switcher that manually switches between turned-on and turned-off of a tracking mode,
wherein the image sensor movement controller controls the movement of the image sensor to track the subject in a case where the tracking mode is turned on.
6. The imaging device according to claim 1 , further comprising:
a monitor or an electronic viewfinder on which an image captured by the image sensor is displayed in real time,
wherein resolution of the monitor and the electronic viewfinder is lower than resolution of the image sensor.
7. An imaging device main body comprising:
a mount to which an imaging lens having a focus adjustment function for performing manual focusing is attached;
an image sensor that images a subject via the imaging lens;
an image sensor movement driver that physically moves the image sensor along an optical axis; and
an image sensor movement controller, including processing circuitry, that controls the movement of the image sensor to track the subject based on a detected defocus amount in a case where the subject is focused by manual focusing of the imaging lens,
wherein one of the following is implemented in the imaging device:
wherein the image sensor movement controller ends the tracking of the subject in a case where the image sensor reaches an end portion of a movable range, and moves the image sensor to a reference position, or
wherein the image sensor movement controller ends the tracking of the subject in a case where the image sensor reaches an end portion of a movable range, and causes the image sensor to stand by at a position of the end portion until the subject is focused again.
8. An imaging device comprising:
an imaging lens that has a focus adjustment function;
an image sensor that images a subject via the imaging lens;
an image sensor movement driver that physically moves the image sensor along an optical axis; and
an image sensor movement controller, including processing circuitry, that controls the movement of the image sensor to track the subject based on a detected defocus amount in a case where the subject is focused,
wherein the image sensor movement controller returns the image sensor to a reference position by moving the image sensor at a moving speed corresponding to a change of the detected defocus amount, and
wherein one of the following is implemented in the imaging device:
wherein the reference position of the image sensor is set at a flange back position defined by the imaging lens,
wherein the image sensor movement controller ends the tracking of the subject in a case where the image sensor reaches an end portion of a movable range, and causes the image sensor to stand by at a position of the end portion until the subject is focused again,
wherein the image sensor movement controller determines that the subject is focused in a case where the detected defocus amount is continuously equal to or less than a threshold value for a predetermined time,
wherein the image sensor movement controller determines that the subject is focused in a case where the detected defocus amount is continuously equal to or less than a first threshold value for a predetermined time and a change amount of the detected defocus amount is continuously equal to or less than a second threshold value for a predetermined time, or
wherein the imaging device further comprises a tracking mode automatic switcher that turns on a tracking mode in a case where the subject is continued to be focused for a predetermined time, and the image sensor movement controller controls the movement of the image sensor to track the subject in a case where the tracking mode is turned on.
9. The imaging device according to claim 8 ,
wherein the detected defocus amount is based on outputs of a plurality of phase difference detection pixels formed on an imaging surface of the image sensor.
10. The imaging device according to claim 8 , further comprising:
a tracking mode manual switcher that manually switches between turned-on and turned-off of a tracking mode,
wherein the image sensor movement controller controls the movement of the image sensor to track the subject in a case where the tracking mode is turned on.
11. The imaging device according to claim 8 , further comprising:
a monitor or an electronic viewfinder on which an image captured by the image sensor is displayed in real time,
wherein resolution of the monitor and the electronic viewfinder is lower than resolution of the image sensor.