FOCUS INFORMATION ACQUISITION DEVICE

摘要

A focus information acquisition device acquires luminance information at two positions having different optical path lengths so as to calculate a spread parameter by calculating a plurality of images having different blurs and perform focus judgment. An optical system (1) focuses an image of an object at a predetermined position. An imaging unit (2) captures an image of the object focused on the imaging plane as an image. According to position information on the luminance information extraction region where the luminance information is acquired and a spread parameter calculated from the luminance information, an optical system control unit (6) acquires optical system setting information for setting a state of the optical system for capturing a focused image of the object in the luminance information extraction region where the luminance information is acquired.