Patent ID: 6085041
Filing Date: 2000-07-04
Classification: G02B

Abstract:
An auto focus system, comprising:a camera body side includinga focus detection device to detect a defocus amount of a photographic lens,a lens movement information acquisition device to acquire, from the photographic lens side, information relating to movement of a focusing lens within the photographic lens,a within-camera correction device to determine a residual defocus amount and to correct the residual defocus amount according to the movement of the focusing lens after a time point of focus detection using the information relating to the movement of the focusing lens and relational information representing a relationship between the defocus amount and the drive amount of the focusing lens, andan information transmission device to transmit to the photographic lens side the corrected residual defocus amount by the within-camera correction device; anda photographic lens side, includinga within-lens conversion device to convert the residual defocus amount transmitted from the information transmission device into a residual drive amount of the focusing lens using within-lens relational information equal to the relational information used by the within-camera correction device, anda lens drive device to drive the focusing lens according to the residual drive amount converted by the within-lens conversion device.