Calcite

Calcite is a negative uniaxial crystal that has high birefringence, wide spectral transmission. Calcite is a negative uniaxial crystal that has high birefringence, wide spectral transmission and availability in reasonably sized rhombs. Although is a fairly soft crystal and is easily scratched, it is ideal material used as visible and near IR polarizers, such as Glan Taylor, Glan Thompson and Glan laser. Carefully select the raw calcite crystals by inspecting them with a cw green laser beam. We have perfected a number of proprietary processes for cutting, grinding and polishing good quality optical surfaces for calcite prism. These skills are evident in the high quality of the finished components, and enable polarizers to be used with very high peak power lasers.  

Refractive Indices, Birefringence ( Dn = ne - no ) and Walk-off Angle at 45° ( r ): no = 1.6557, ne = 1.4852, Dn = -0.1705, r = 6.20° at 0.63 mm no = 1.6629, ne = 1.4885, Dn = -0.1744, r = 6.32° at 1.30 mm

Sellmeier Equation ( l in mm): no2 = 2.69705 + 0.0192064/( l2 - 0.01820) - 0.0151624 λ2 ne2 = 2.18438 + 0.0087309/( l2 - 0.01018) - 0.0024411 λ2