Specifications:
| Materials | Optical grade sapphire crystals | Diameter Range | ~300mm |
| Diameter Tolerance | +0.0/-0.2mm | Thickness Tolerance | +/-0.2mm |
| Surface Quality | 60/40 S/D | Frings (N) | 3 |
| Irregularity (delta N) | 1 | Centration | 3' |
| Chamfer | 0.1-0.3mmx45 degree |
Physical and Optical Properties:
| Transmission Range | 0.17 to 5.5 μm | Refractive Index | No 1.75449; Ne 1.74663 at 1.06 μm (1) |
| Reflection Loss | 14% at 1.06 μm | Absorption Coefficient | 0.3 x 10-3 cm-1 at 2.4 μm(2) |
| Reststrahlen Peak | 13.5 μm | dn/dT | 13.1 x 10-6 at 0.546 μm(3) |
| dn/dμ = 0 | 1.5 μm | Density | 3.97 g/cc |
| Melting Point | 2040°C | Thermal Conductivity | 27.21 W m-1 K-1 at 300K |
| Thermal Expansion | 5.6 (para) & 5.0 (perp)x 10-6/K* | Hardness | Knoop 2000 with 2000gindenter |
| Specific Heat Capacity | 763 J Kg-1 K-1 at 293K(4) | Dielectric Constant | 11.5 (para) 9.4 (perp) 、at 1MHz |
| Youngs Modulus (E) | 335 GPa | Shear Modulus (G) | 148.1 GPa |
| Bulk Modulus (K) | 240 GPa | Elastic Coefficients | C11=496 C12=164 C13=115 C33=498 C44=148 |
| Apparent Elastic Limit | 300 MPa (45,000 psi) | Poisson Ratio | 0.25 |
| Solubility | 98 x 10-6 g/100g water | Molecular Weight | 101.96 |
| Class/Structure | Trigonal (hex), R3c |
Chemically, sapphire is single crystal or aluminum oxide (Al2O3) is used in transmission range from 0.2 - 5.5μm, sapphire is suitable for MWIR 3-5μmthermal imaging applications. Sapphire lenses are made from single crystal sapphire, they are ideal for demanding applications because of their extreme surface hardness, high thermal conductivity, high dielectric constant and resistance to common chemical acids and alkalis. Sapphire is the second hardest crystal next to diamonds and, because of their structural strength, sapphire windows can be made much thinner than other common dielectric windows with improved transmittance. Hangzhou Shalom EO provide the customized lenses and balls upon customer's request.
Curves:
1. Transmission of Sapphire at Infrared wavelength range (no coating)
2. Transmission of Sapphire at UV wavelength range ( no coating)
