I guess the main confusion of defining this lens is probably the setting of depth/frequency. lpfwlB'~9
8)W?la8'p
The main fresnel lens types are: n~,]KdU]
k,;lyE
* Constant groove depth. TRk
?8
* Contant groove pitch types. Krp
<bK6
W>?f^C!+m
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. P e$^Mo.q
Y| m_qB^_
Hope this helps!!
