I guess the main confusion of defining this lens is probably the setting of depth/frequency. n[]tXrhU
Q<KvBgmT
The main fresnel lens types are: Wt=|
g q}I[N
* Constant groove depth. >j'ZPwj^
* Contant groove pitch types. )QG<f{wS
1XnZy5fEo
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. Ty<L8+B|
+=mkCU
Hope this helps!!