I guess the main confusion of defining this lens is probably the setting of depth/frequency. [?0d~Q(R# 5's~>up& The main fresnel lens types are: >''U H t(n%;< * Constant groove depth. WXw}^v * Contant groove pitch types. I/6)3 su% HD>q(cK_|8 So if your depth is fixed you will define +ve value in the cell and to specify the "height" or "depth" of each groove feature. If the frequency of the groove is fixed then you use -ve value. Say putting down - 5 this implies that there are 5 grooves with a unit length. i)a%!1Ar ?)D^~/
A Hope this helps!!
