Optical Property
Refractive Index, at 486 nm | nf = 1.4632 |
Refractive Index, at 588 nm | nd = 1.4586 |
Refractive Index, at 656 nm | nc = 1.4565 |
Reflection Loss, % for two surfaces at 400 nm | 7.0 |
Reflection Loss, % for two surfaces at 588 nm | 6.8 |
Birefringence Constant, (nm/cm) | 3.61 |
Abbe Constant | 67.6 |
Physical Property
Density, g/cm3 | 2.203 |
Crystal Structure | Amorphous glass |
Bubbles/Inclusions | none |
Total metallic impurities, ppm | 25-30 |
OH- Content, ppm | 400-500 |
Thermal Conductivity, W · m-1· K-1 | 1.38 |
Specific Heat Capacity, J Kg-1K-1 | 703 |
Specific Heat Capacity, J Kg-1K-1 | 0.55 x 10-6 |
Softening Point, °C | 1730 |
Annealing Point, °C | 1180 |
Strain Point, °C | 1075 |
Max. Service Temperature, at 1150°C | continuous |
Max. Service Temperature, at 1300°C | limited time |
Dielectric Constant, at 1kHz | 3.91 |
Dielectric Strength, kV/cm at 20°C | 250-400 |
Young's Modulus (E), GPa at 25°C | 73 |
Shear Modulus (G), GPa at 25°C | 31 |
Rupture Modulus, MPa at 25°C | 50 |
Bulk Modulus (K), GPa at 25°C | 36.9 |
Apparent Elastic Limit, MPa | 55 |
Poisson Ratio, at 25°C | 0.17 |
Compressive Strength, GPa | 1.1 |
Tensile Strength, MPa | 50 |
Knoop Hardness, kg/mm2 | 500 |
Spectrum |
