A focus control device includes a processor including hardware, the processor being configured to implement: an area setting process that sets a plurality of areas to a captured image that has been captured by an imaging section, each of the plurality of areas including a plurality of pixels; a direction determination process that determines whether a target in-focus position lies in a NEAR direction or a FAR direction with respect to a reference position with respect to some or all of the plurality of areas set to the captured image to calculate a direction determination result with respect to each of the plurality of areas, the target in-focus position being a target of an in-focus object plane position; and a focus control process that preferentially brings an area among the plurality of areas that is situated away from the imaging section into focus based on the direction determination result.

A photographing apparatus includes an imaging-plane tilter configured to tilt an imaging plane, formed by a photographing optical system, relative to a plane that is orthogonal to an optical axis of the photographing optical system; a focus detector provided with a plurality of focus detection areas; and a tilt controller configured to control the imaging-plane tilter to tilt the imaging plane based on focus deviation amounts of the plurality of focus detection areas.

An image pickup apparatus includes an imaging unit that acquires a first image by capturing an object at a first focusing position, and acquires a second image after acquiring the first image, by capturing the object at a second focusing position different from the first. The second image has different blur than the first image. A depth information determination unit determines depth information of the object on the basis of a difference in blur between the first image and the second image. A focusing position setting unit sets a focus movement amount that is a difference between the first focusing position and the second focusing position, in accordance with an F-number of the imaging unit. The second focusing position is set such that an absolute value of the focus movement amount is larger when the F-number is large, as compared to when the F-number is relatively small.

An image pickup apparatus includes an imaging unit that acquires a first image by capturing an object at a first focusing position, and acquires a second image after acquiring the first image, by capturing the object at a second focusing position different from the first. The second image has different blur than the first image. A depth information determination unit determines depth information of the object on the basis of a difference in blur between the first image and the second image. A focusing position setting unit sets a focus movement amount that is a difference between the first focusing position and the second focusing position, in accordance with an F-number of the imaging unit. The second focusing position is set such that an absolute value of the focus movement amount is larger when the F-number is large, as compared to when the F-number is relatively small.

An imaging device to which an imaging optical system is attachable, includes a correction data generating unit that generates correction data to correct a sensitivity difference of first phase difference detecting pixel cells and second phase difference detecting pixel cells; and a signal correcting unit that corrects at least one of an output signal of the first phase difference detecting pixel cells and an output signal of the second phase difference detecting pixel cells in accordance with the correction data, in which the correction data generating unit calculates two ratios to generate the correction data based on the two ratios.

An imaging device to which an imaging optical system is attachable, includes a correction data generating unit that generates correction data to correct a sensitivity difference of first phase difference detecting pixel cells and second phase difference detecting pixel cells; and a signal correcting unit that corrects at least one of an output signal of the first phase difference detecting pixel cells and an output signal of the second phase difference detecting pixel cells in accordance with the correction data, in which the correction data generating unit calculates two ratios to generate the correction data based on the two ratios.

A focusing method and a focusing system based on a distance sensor of mobile terminal is provided. The method may include: acquiring an initial distance between a camera and an object to be shot by using the distance sensor; judging whether the distance between the camera and the object changed; in response to judging that the distance changed, acquiring a micro-adjustment range of a motor according to the distance; controlling the motor to move based on the micro-adjustment ranges; collecting images from the camera in a real-time manner; acquiring focus values of the collected images; and moving the motor to a position corresponding to a largest focus value of the focus values to focus the camera.

A focusing method and a focusing system based on a distance sensor of mobile terminal is provided. The method may include: acquiring an initial distance between a camera and an object to be shot by using the distance sensor; judging whether the distance between the camera and the object changed; in response to judging that the distance changed, acquiring a micro-adjustment range of a motor according to the distance; controlling the motor to move based on the micro-adjustment ranges; collecting images from the camera in a real-time manner; acquiring focus values of the collected images; and moving the motor to a position corresponding to a largest focus value of the focus values to focus the camera.

A direction judgment unit calculates a first evaluation value based on an image signal of a first focus detection region among focus detection regions to judge a drive direction of a focus lens to be in focus and calculates a second evaluation value based on an image signal of at least one second focus detection region smaller than the first region, the focus detection regions being at least partly the same and being different in size. A control unit determines whether a change of the second evaluation value is a monotonous change when the focus lens is slightly driven a first number of times in a first direction judged on the basis of the first evaluation value and the focus lens is slightly driven a second number of times smaller than the first number of times in a second direction opposite to the first direction, and the control unit performs focus adjustment on the basis of the second evaluation value when the change of the second evaluation value is not a monotonous change.

A focus adjustment method comprising setting a first range including at least one AF area, or a second range including the first range, every time the defocus amount is detected, selecting the first range or the second range based on a focus target position of an AF area included in the second range, and a reference position, updating the reference position based on the plurality of focus target positions of AF areas included in the range that has been selected, and the reference position, and selecting an AF area used in the focus adjustment from the plurality of AF areas, based on the plurality of focus target positions of AF areas included in the range that has been selected, and the reference position that has been updated.