I guess the main confusion of defining this lens is probably the setting of depth/frequency. R 9\*#c
;_(4Q*Yx
The main fresnel lens types are: ,qxu|9L
c@7rqHU-0
* Constant groove depth. lo+A%\1
* Contant groove pitch types. .q>iX E_c
ux4POO3C|
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. GTd,n=
{ < KVx9
Hope this helps!!
