光学设计软件zemax源码：
This DLL models an nular aspheric
surface as described in:
"Annular surfaces in annular field systems"
By Jose M. Sasian
Opt. eng. 36 (12) P 3401-3401 December 1997
This surface is essentially an odd aspheric surface with an offset in the aspheric terms.
The sag is given b ...
