Allow me to repost here for depth/frequency setting %$
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The main fresnel lens types are: 3ySP*J5
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* Constant groove depth. 4QnJ;&~
* Contant groove pitch types. /Xi:k
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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. {PHxm
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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. DTdL|x.{
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For conic: check conic section using Wikipedia and you should see what conic constant means. _Gy*" ;E
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