Patent ID: 7358999

Claim:
An apparatus comprising: an image sensing device for receiving light from an object, said image sensing device having a plurality of pixels for receiving light from the object upon separating the light into respective ones of different color components, and said image sensing device outputting a signal based on the light from the object; an optical guidance device for accepting light rays in different directions from a same part of the object and guiding the light rays to said image sensing device; and a phase-difference determining device for determining a phase difference in an output signal of said image sensing device with respect to each of the light rays accepted in the different directions by said optical guidance device, said phase-difference determining device determining the phase difference based upon a signal obtained by combining output signals of pixels, among said plurality of pixels, that correspond to prescribed different color components, wherein said phase-difference determining device performs addition and averaging phase-differences of a pair of objects obtained in different timings and changes each weighting for adding a plurality of said phase-differences based on a determination result of a S/N ratio of said output signal of said image sensing device with respect to each of the light rays accepted in the different directions by said optical guidance device.