Crystal Iceland Spar (CaCO3)
Transmission of synthetic calcite
Crystals of Iceland Spar (Optical Calcite) are famous for high birefringence and transparence in broad region of spectrum. It is ideal material for manufacturing polarizing prisms, beam divergent elements, laser gates and other optical devices.
Natural deposits of calcite crystals acceptable in optics are rare.
Calcite crystal growth is realized hydrothermal method analogical method is used in synthetic quartz manufacturing process.
Synthetic calcite no dispersion in He-Ne beam. In light transmission synthetic calcite is identical to the best sorts of natural crystals of this mineral. .
BASE PROPERTIES
|
PARAMETER |
|
VALUE |
|
|
|
|
|
|
| OPTICAL |
|
| |
Transmission Range |
|
0.2 - 2.5 µm |
|
| |
Reflection Loss |
|
for two surfaces
at 0.22 µm for o-ray - 16.9%; for e-ray – 9.2%;
at 0.71 µm for o-ray – 11.7%; for e-ray – 7.4%; |
| PHSYCAL |
|
| |
Density |
|
2,711 g/cm3при 289 K |
|
| |
Melting Temperature |
|
1612 K at 10,3 MPa |
|
| |
Decomposition Temperature |
|
1167 K |
|
| |
Thermal Expansion |
|
Parallel 25.1 x 10-6 1/K at 323 K
Perpendicular 4,9 x 10-6 1/K at 323 K |
|
| |
Moh,s hardness scale |
|
3 |
|
| |
Elastic Constant |
|
C11=13.17 x 10 Din/cm, C12=4.82 x 10 Din/cm,
C13=5.68 x 10 Din/cm, C14=-2.0 x 10 Din/cm,
C22=8.11 x 10 Din/cm,
C44=3.5 x 10 Din/cm
|
| CHEMICAL |
|
| |
Solubility in water |
|
0,0014 g/l at 298 K |
|
| |
Molecular Weight |
|
100.09 |
|
| |
Lattice constant |
|
a=4.994 A, c=17.081 A, v=368.8 A3 |
|
| |
Crystal Class |
|
Thrigonal, Space group - R3c.
Прекрасно раскалывается по плоскости (1011). |
|
Optical Quality
Iceland spar is available in three grades by optical absorption at four wavelengths
(index of absorption, 1/ cm).
Spectral Region
|
Quality Grade
|
Index of absorption, 1/
см |
| 220 nm |
310 nm |
400 nm |
700 nm |
| UV |
1
|
0.31 |
0.22 |
- |
- |
|
2
|
0.35 |
0.31 |
- |
- |
|
3
|
0.45 |
0.45 |
- |
- |
| V |
1
|
- |
- |
0.046 |
- |
|
2
|
- |
- |
0.097 |
- |
|
3
|
- |
- |
0.155 |
- |
| IR |
1
|
- |
- |
- |
0.009 |
|
2
|
- |
- |
- |
0.018 |
|
3
|
- |
- |
- |
0.046 | |
Spectral Region Ultra-Violet (UV), Visible (V) and Infra-Red (IR)
REFRACTIVE INDEX
|
Wavelength, µm |
|
Refractive Index, no |
|
Refractive Index, ne |
|
|
|
|
|
|
|
|
|
|
| |
0.214 |
|
1.8458 |
|
1.5599 |
|
| |
0.218 |
|
1.8458 |
|
1.5551 |
|
| |
0.227 |
|
1.8130 |
|
1.5491 |
|
| |
0.231 |
|
1.8024 |
|
1.5455 |
|
| |
0.245 |
|
1.7797 |
|
1.5373 |
|
| |
0.257 |
|
1.7605 |
|
1.5301 |
|
| |
0.275 |
|
1.7415 |
|
1.5227 |
|
| |
0.303 |
|
1.7196 |
|
1.5136 |
|
| |
0.330 |
|
1.7052 |
|
1.5075 |
|
| |
0.361 |
|
1.6932 |
|
1.5022 |
|
| |
0.396 |
|
1.6833 |
|
1.4978 |
|
| |
0.405 |
|
1.6843 |
|
1.4968 |
|
| |
0.434 |
|
1.6755 |
|
1.4942 |
|
| |
0.436 |
|
1.6752 |
|
1.4942 |
|
| |
0.468 |
|
1.6703 |
|
1.4919 |
|
| |
0.480 |
|
1.6687 |
|
1.4912 |
|
| |
0.481 |
|
1.6686 |
|
1.4912 |
|
| |
0.486 |
|
1.6678 |
|
1.4907 |
|
| |
0.509 |
|
1.6654 |
|
1.4898 |
|
| |
0.527 |
|
1.6634 |
|
1.4887 |
|
| |
0.546 |
|
1.6618 |
|
1.4880 |
|
| |
0.560 |
|
1.6605 |
|
1.4874 |
|
| |
0.578 |
|
1.6593 |
|
1.4868 |
|
| |
0.579 |
|
16584 |
|
1.4864 |
|
| |
0.579 |
|
1.6584 |
|
1.4865 |
|
| |
0.636 |
|
1.6556 |
|
1.4852 |
|
| |
0.644 |
|
1.6551 |
|
1.4850 |
|
| |
0.656 |
|
1.6544 |
|
1.4846 |
|
| |
0.707 |
|
1.6521 |
|
1.4835 |
|
| |
0.768 |
|
1.6497 |
|
1.4826 |
|
| |
0.795 |
|
1.6489 |
|
1.4822 |
|
|
