We report the operation of a new instrument which measures with ± 5 nm precision the shape of steep aspheric surfaces. The instrument makes use of contacting probes, and its working is based on an optical differential technique. Special attention is paid to the mechanical construction, and a detailed error analysis is given.
J. G. Dil,
J. C. Driessen,
"High-Precision Measurement Of Aspheric Surfaces", Proc. SPIE 0235, Aspheric Optics: Design, Manufacture, Testing, (13 May 1981); doi: 10.1117/12.958966; https://doi.org/10.1117/12.958966