| 摘要 |
PURPOSE:To permit complete measure of decentering amount for the respective surfaces in the measured lens system by a method wherein two deviation amounts of the system including the surface on which measure of the deviation amount is impossible are obtained using a pair of conjugate focusing relationships for an arbitrary surface in the measured lens system, on which surface measure of the deviation amount is possible. CONSTITUTION:It is assumed that a measured lens 20 is rotated about a certain axis of rotation B, two surfaces S1 and S2 of the measured lens 20 have decentering amounts epsilon(1) and epsilon(2) relative to the axis of rotation B, respectively, and measure on the second surface S2 is impossible. The transmitted image of an index I illuminated by a light source 1 is focused at a position of I2 through the first surface S1 of the measured lens 20. The measured lens 20 is rotated to measure the deviation amoutn DELTA(1) of the transmitted image I2. Next, the index I is moved to meet the different conjugate relationship for the first surface S1 of the measured lens 20 and then focused to measure the deviation amount DELTA(1)' of the transmitted image I2 in this state. By so doing, it becomes possible to achieve the complete decentering amount measure for the respective surfaces in the measured lens system. |
