Allow me to repost here for depth/frequency setting + {e`]t>_
The main fresnel lens types are: ;{gT=,KQ`
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* Constant groove depth. zSXA=
* Contant groove pitch types. iZ "y7s
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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. \<V)-eB
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For radius, this is the curvature of the base surface. If you define one such lens and chaneg the radius and you shall see what it means. A graphic tells lounder than words. QD4:W"i
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For conic: check conic section using Wikipedia and you should see what conic constant means. S/7l/DFb
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