| 摘要 |
PROBLEM TO BE SOLVED: To provide a lens inspection method, in which aberration amount of a lens to be inspected is measured with satisfactory accuracy, even if an interferometer is not maintained or controlled strictly. SOLUTION: A luminous flux which is transmitted through a reference lens, a luminous flux which is transmitted through the lens to be inspected are made to interfere, and the aberration amount of the lens to be inspected is inspected, on the basis of generated interference fringes. At this time, the optical axis of the lens to be inspected is made to coincide with the rotation center of the lens to be inspected, the lens to be inspected is fringe-scan measured at a position of 0 deg., and the result of its measurement is subjected to Zernike-coefficient development. The lens to be inspected is turned by 90 deg. about its optical axis, it is fringe-scan measured at a position of 180 deg. with reference to the position of 0 deg., and the result of its measurement is Zernike-coefficient developed. Only the change amount due to the rotation of the lens to be inspected is calculated on the basis of the Zernike-coefficient, and the aberration amount of the lens to be inspected, in which the aberration amount of the interferometer is removed from the change amount is calculated.
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