| 摘要 |
The method involves using interferometry of Shack Hartmann sensing to measure wave front deformations. The method involves constructing a spherical auxiliary wave in a diffractive optical element. This is encoded with the same average wave front curvature and the same direction of curvature as an aspherical wave. The auxiliary wave can be easily separated from the actual aspherical wave front by a small lateral focus shift with appropriate filtering. The aspherical wave meets the test surface at a right angle and is reflected and then deformed by a diffractive element selectively into a planar or spherical wave. This is then caused to interfere with the reference wave, The auxiliary wave is used to calibrate the interference arrangement in which several interferometry settings are realized successively, including a cat's eye position and different rotational positions of the aspherical test surface or an absolute tested spherical auxiliary surface.
|
