Patent ID: 8089612

Claim:
A position detection apparatus which detects a position of a target object, the apparatus comprising: a light source configured to emit light having a wavelength width onto the target object; an imaging optical system configured to form an image of the light from the target object on an image sensor; a first obtaining unit configured to obtain imaging characteristics of said imaging optical system for a plurality of light beams, having different wavelength with each other, of the light having the wavelength width; a second obtaining unit configured to obtain optical images of the target object for the plurality of the light beams; a restoration unit configured to restore optical images of the target object for the plurality of the light beams by correcting, deterioration in the optical images of the target object obtained by said second obtaining unit attributed to said imaging optical system, based on the imaging characteristics of said imaging optical system obtained by said first obtaining unit; a generation unit configured to generate an optical image of the target object for light including the plurality of the light beams by synthesizing the optical images of the target object for the plurality of the light beams, which are restored by said restoration unit; and a determination unit configured to determine the position of the target object based on the optical image of the target object for the light including the plurality of the light beams, which is generated by said generation unit.