Patent ID: 8605204

Claim:
A method for adjusting a tracking curve, said method comprising: a first adjusting step of adjusting a first tracking curve which has been set so as to keep an in-focus state between a position of a magnification-varying lens and a position of an image sensor, the magnification-varying lens being moved in an optical axis direction during a variation of magnification, the image sensor generating an image signal by photoelectrically converting an optical image formed by an image-pickup optical system, and the image-pickup optical system including the magnification-varying lens and a focus lens moved in the optical axis direction during focusing; and a second adjusting step of adjusting a second tracking curve which has been set so as to keep the in-focus state between the position of the magnification-varying lens and a position of the focus lens for an object distance, wherein in the first adjusting step, the focus lens is fixed at each of two points on a set second tracking curve, one of the magnification-varying lens and the image sensor is fixed at a position corresponding to the focus lens, the other of the magnification-varying lens and the image sensor is moved to a position that provides a peak of an evaluation value representing a contrast of the image signal, and a difference between a position of the image sensor corresponding to the position of the focus lens on a set first tracking curve and a position of the image sensor which provides the peak is obtained; and wherein in the second adjusting step, the magnification-varying lens and the image sensor are fixed at each of two points on the first tracking curve adjusted by the first adjusting step, the focus lens is moved to a position that provides a peak of the evaluation value, and a difference between a position of the focus lens corresponding to a position of the magnification-varying lens on the set second tracking curve and the position of the focus lens which provides the peak is obtained.