To realize automatic focusing with high precision in which out of focus by the type of a light source is suppressed in an automatic focusing camera with interchangeable lens of a TTL phase difference detection system.
This focus detecting device has a focus detection unit (26) of the TTL phase difference detection system, color aberration information acquisition means (100, 10) for acquiring information regarding color aberration corresponding to wavelength of light of an interchangeable lens unit, a storage means (100) for storing the correction value of the color aberration based on a light source color, a first photometric sensor (7) which performs photometry mainly of a visible light area among light fluxes which have passes through the lens unit, a second photometric sensor (31) which performs photometry mainly of a wavelength area longer than that of a visible light, a correction value acquisition means (100) for acquiring the correction value from the storage means according to output difference between the first and second photometric sensors, and a correction means (100) for correcting a defocusing amount according to the information about the color aberration and the correction value.
Shiro Takayanagi
Yasuhiro Otsuka
Shuji Kimura