Calcite
Description:
Calcite is a natural crystal that has high birefringence and wide spectral transmission and available in reasonably sized rhombs. It is well known material for polarization optics.
Applications:
Negative uniaxial crystals and commonly used as visible and near IR polarizers.
Physical and Optical Properties:
| Transparency range | 350~2300nm |
| Partical shape | Crystalline rhombihedral |
| Density | 2.7 g/cm3 |
| Hygroscopic susceptibility | Low susceptibility to moisture |
| Hardness | 3 Mohs |
| Thermal expansion coefficient | αa=24.39x10-6/k; αc=5.68x10-6/k |
| Crystal class | Negative uniaxial with no=na=nb, ne=nc |
| Refractive index, birefringence(Δ=ne-no) and walk-off angle at 45 (ρ) | no =1.6557, ne=1.4852 |
| Δn=-0.1705, ρ= 6.20 o @ 630nm | |
| no =1.6629, ne =1.4885 | |
| Δn=-0.1705, ρ= 6.20 o @ 1300nm | |
| Sellmeier equation | no2=2.69705+0.0192064/(λ2-0.01820)-0.0151624λ2 |
| ne2=2.18438+0.0087309/(λ2-0.01018)-0.0024411λ2 |
Specifications:
| Diameter | max 30~40mm |
| Length | max 25~35mm |
| Surface quality | 20/10 scratch/dig |
| Beam deviation | < 3 arc min |
| Optical axis orientation | +/-0.5 |
| Flatness | λ/4 @633nm |
| Transmission wavefront distortion | <λ/2 @633nm |
Note: To inquire or order a finished Calcite crystal, please provide detailed specifications as listed in above.