Focus correcting apparatus for an auto focus camera

A focus correcting apparatus for an auto focus camera having a non-TTL type distance measuring device, characterized by:

• a photo-taking lens of a focusing type other than a total lens movement focusing type;
• a first memory for memorizing an amount of deviation of an imaging point from the surface of film caused by irregularity during lens assembly or irregularity of the dimensions of lens parts or the refractive indices of lens materials;
• a calculator for calculating an amount of correction movement of a focusing lens group from the memorized amount in said first memory and an amount of movement of the imaging point per unit amount of movement of the focusing lens group;
• and
• a lens driver for driving the focusing lens group on the basis of the final amount of movement consisting of an amount of movement of the focusing lens group calculated from a measured distance value obtained by said non-TTL type distance measuring device, plus the amount of correction movement of the focusing lens group found by said calculation.

A method for performing a focus correction of an auto focus camera having a non-TTL type distance measuring device and using a photo-taking lens of a focusing type other than a total lens movement focusing type, comprising the steps of:

• memorizing an amount of deviation of an imaging point from the surface of film caused by irregularity during lens assembly or irregularity of the dimensions of lens parts or the refractive indices of lens materials;
• calculating an amount of correction movement of a focusing lens group from the memorized amount and an amount of movement of the imaging point per unit amount of movement of the focusing lens group;
• and
• driving the focusing lens group on the basis of a final amount of movement consisting of the amount of movement of the focusing lens group calculated from a measured distance value obtained by said non-TTL type distance measuring device, plus the amount of correction movement of the focusing lens group found by said calculation.