| 摘要 |
PROBLEM TO BE SOLVED: To provide a Fizeau interferometer and a Fizeau lens which can measure the surface accuracy of a lens with accuracy even when the radius of curvature of the spherical surface to be inspected of the lens is smaller than the outside diameter of the lens. SOLUTION: The Fizeau lens 10 of a Fizeau interferometer is constituted of a first lens (negative lens) L1 which scatters the light made incident from a laser light source and second to seventh lenses (positive lenses) L2-L7 which converge the light rays scattered by the negative lens L1 to a focal point P by condensing the light rays and, at the same time, correct the spherical aberration caused by the negative lens L1. The refractive indexes of the first lens L1 and second to sixth lenses L2-L6 are adjusted to >=1.69 and the refractive index of the seventh lens L7 having a Fizeau surface F is adjusted to >=1.79.
|
