| Products -> Crystal -> Calcite |
| 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 Thompson, and Glan Taylor Glan laser. |  |
| Dimension Tolerance | ±0.1 |
| Optical Axis Orientation | ±0.5deg |
| Wavefront Distortion | <λ/2 at 633nm |
| Surface Flatness | <λ/4 at 633 nm |
| Surface Quality | 20/10 Scratch and Dig |
| Parallelism | <15 arc seconds |
| Perpendicularity | <10 arc minutes |
| Clear Aperture | >Central 90% |
| AR-Coating | R<0.25%@ 1550nm±40 nm |
| Crystal Structure | Crystalline rhombihedral |
| Density | 2.7 g/cm3 |
| Mohs Hardness | 3 |
| Hygroscopic Susceptibility | Low |
| Transparency Range | 350nm ~ 2300nm |
| Thermal Expansion Coefficient | aa=24.39x10-6/K |
| ac=5.68x10-6/K | |
| Crystal Class | Negative uniaxial with no=na=nb, ne=nc |
Refractive Index Birefringence (Δn=ne-no) Walk-Off Angle at 45 deg(ρ) |
no=1.6557, ne=1.4852, Δn = -0.1705, ρ=6.32 @633nm no=1.6381, ne=1.4783, Δn = -0.1598, ρ=6.20 @1300nm |
| Sellmeier Equations ( in um) | no2=2.69705+0.0192064/(
λ2-0.01820)-0.0151624λ2 ne2=2.18438+0.0087309/( λ2-0.01018)-0.0024411λ2 |