Patent ID: 7440089

Claim:
A method of measuring the decentering of a lens, comprising the steps of: a first step of measuring a profile of an examined surface of the lens by moving a probe along the examined surface, starting from a first reference position which is a position separated by a predetermined amount from a predetermined position on the examined surface of the lens; a second step of measuring the profile of the examined surface of the lens by moving the probe along the examined surface, starting from a second reference position which is a position-separated by a predetermined amount from the predetermined position, and moving in a direction opposite to the scanning direction of the first step after a rotation of the lens; a step of calculating the decentering amount of the examined surface of the lens by using the measurements obtained in the first and second steps; and a step of indicating the calculated decentering amount of the examined surface of the lens, wherein the probe is in direct, physical contact with the lens during the first and second steps.