Based on theoretical analysis and experiments, a new method of copying micro-radial grating having division diameter less than 30 mm is proposed. It solves effectively the problem of contacting poor between the pattern plate and the copied radial grating during the copy process and the problem of great losses on accuracy and contrast.
Hong-Lin Yu, Hong-Lin Yu,
"New method of copying a microradial grating", Proc. SPIE 3557, Current Developments in Optical Elements and Manufacturing, (5 August 1998); doi: 10.1117/12.318313; https://doi.org/10.1117/12.318313