A digital microscope and a focusing thereof are provided. The microscope integrates a focusing lens unit, a zooming lens unit and related control circuits into the interior of the microscope. The control unit executes a focus searching algorithm and focus tracking algorithm, controls movement of the focusing lens unit and the zooming lens unit and achieves auto-focus by adjusting the image distance and makes the microscope zoom by adjusting the focal length. This improves the focusing efficiency and shortens the focusing time greatly. The microscope can achieve continuous zooming and tracking by the zoom tracking algorithm and the image is kept clear in the zooming process. The microscope adjusts the brightness of the assist light source at the front end of the microscope according to the change of the amount of light transmission by the control unit executing the exposure algorithm to ensure uniform exposure.

A lens control apparatus and a control method thereof are disclosed. The lens control apparatus includes a microprocessor which obtains a correction defocus amount so that the correction defocus amount obtained by the microprocessor when a zoom speed is a first speed is greater than the correction defocus amount obtained by the microprocessor when a zoom speed is a second speed which is less than the first speed.

A camera body according to the present disclosure is a camera body to which a lens barrel including an optical system is detachable and reattachable, the optical system being configured to include a plurality of lenses. The camera body includes: a controller which controls the camera body; an image sensor which obtains an optical image formed by the optical system; and an image sensor driver which drives the image sensor in an optical axis direction of the optical system. The controller detects optical feature amounts of a plurality of frames in a state where the image sensor is at an identical position in the optical axis direction, detects a frame in which a change amount of an optical feature amount calculated from a plurality of the detected optical feature amounts has exceeded a predetermined threshold, and drives the image sensor driver to move the image sensor from the identical position to a reference position provided in a movable range when there is a plurality of the frames in which the change amount has exceeded the predetermined threshold.

A processing device which obtains distance information of a subject, including: a calculation unit configured to calculate the distance information of the subject from a difference in blur degree of a plurality of images photographed by an imaging optical system; a correcting unit configured to correct the distance information using correction data in accordance with an image height in the imaging optical system; and an extraction unit configured to extract at least one frequency component from each of the plurality of images, wherein the calculation unit calculates the distance information from a difference in blur degree in the plurality of images in the at least one frequency component; and the correcting unit corrects the distance information using correction data in accordance with an image height in the at least one frequency component.

A processing device which obtains distance information of a subject, including: a calculation unit configured to calculate the distance information of the subject from a difference in blur degree of a plurality of images photographed by an imaging optical system; a correcting unit configured to correct the distance information using correction data in accordance with an image height in the imaging optical system; and an extraction unit configured to extract at least one frequency component from each of the plurality of images, wherein the calculation unit calculates the distance information from a difference in blur degree in the plurality of images in the at least one frequency component; and the correcting unit corrects the distance information using correction data in accordance with an image height in the at least one frequency component.

A method is disclosed for ascertaining a focus image distance of an optical sensor, which is provided with a lens, of a coordinate-measuring apparatus onto a workpiece to be measured, wherein the optical sensor and/or the workpiece are movable in a Z direction such that a distance in the Z direction between the workpiece and the optical sensor is variable. Further, a corresponding coordinate-measuring apparatus and a computer program product are disclosed.

A method is disclosed for ascertaining a focus image distance of an optical sensor, which is provided with a lens, of a coordinate-measuring apparatus onto a workpiece to be measured, wherein the optical sensor and/or the workpiece are movable in a Z direction such that a distance in the Z direction between the workpiece and the optical sensor is variable. Further, a corresponding coordinate-measuring apparatus and a computer program product are disclosed.

A focal point detection device comprising: an image sensor having a focal point detection pixel, a pixel data generation section to generate pixel data of a basis part and a reference part corresponding to a predetermined AF area using an output of the focal point detection pixel, a plurality of filter sections having different frequency characteristics to perform filter processing on the pixel data, a detection section to detect contrast of subject image data configured with a plurality of pieces of pixel data of the basis part and the reference part, and a calculation section to select a filter section from among the plurality of filter sections depending on the contrast output by the detection section, to perform correlation calculation using pixel data on which the filter processing is performed by the selected filter section to calculate a defocus amount.

A focal point detection device comprising: an image sensor having a focal point detection pixel, a pixel data generation section to generate pixel data of a basis part and a reference part corresponding to a predetermined AF area using an output of the focal point detection pixel, a plurality of filter sections having different frequency characteristics to perform filter processing on the pixel data, a detection section to detect contrast of subject image data configured with a plurality of pieces of pixel data of the basis part and the reference part, and a calculation section to select a filter section from among the plurality of filter sections depending on the contrast output by the detection section, to perform correlation calculation using pixel data on which the filter processing is performed by the selected filter section to calculate a defocus amount.

The spatial resolution of captured plenoptic images is enhanced. In one aspect, the plenoptic imaging process is modeled by a pupil image function (PIF), and a PIF inversion process is applied to the captured plenoptic image to produce a better resolution estimate of the object.