Specification :

Lenses have many application ranging from the simple collection of the scaning of laser beams to precise imaging and image transfer.
Waveplates are made from birefringent material. The velocities of the extraordinary and ordinary rays through the birefringent materials vary inversely with their refractive indices. The difference in velocities gives rise to a phase difference when the two beams recombine. In the case of an incident linearly polarized beam this is given by:

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