Patent ID: 8526807

Claim:
A focus detecting apparatus comprising: a micro lens array arranged with a plurality of micro lenses; a photo detector that has a plurality of detecting elements provided in correspondence with the micro lenses and receives light flux from an optical system via the micro lenses; and a focus detector that selects a pair of groups of detecting elements from the plurality of detecting elements based on an F-value of the optical system and a brightness of the light flux from the optical system, and detects a focus adjustment status of the optical system based on a pair of light receiving signals obtained in the groups of detecting elements, wherein at a time of selecting the pair of groups of detecting elements from the plurality of detecting elements, the focus detector selects the pair of groups of detecting elements based on a table having a relationship between an F-value of the optical system and a brightness of the light flux from the optical system and arrangement patterns of the detecting elements, constituting the pair of group of detecting elements.