Patent ID: 9131142
Filing Date: 2015-09-08
Classification: G02B,G03B,G06K,H04N

Abstract:
1. A focusing device comprising: an optical system that includes a focusing lens; an image sensor that captures a subject image formed via the optical system and outputs an image signal containing a plurality of color components; a filter that is inserted on an optical axis extending between the optical system and the image sensor and adjusts an amount of incident light to the image sensor via the optical system; an inserting unit that inserts the filter on the optical axis and moves the filter off the optical axis; an edge detection unit that detects an edge in correspondence to each color component among the plurality of color components contained in the image signal; a differential value calculation unit that calculates a differential value of an edge strength of the edge detected by the edge detection unit, in correspondence to the each color component; and a decision-making unit that determines a moving direction along which the focusing lens is to move for purposes of focus adjustment of the optical system based upon the differential value calculated by the differential value calculation unit, wherein: the decision-making unit determines the moving direction if the filter has been inserted by the inserting unit.