IRG27 by Schott
Standard
Very Common
Environmentally Dangerous
Refractive Index vs Wavelength
Refractive Index Calculator
dn/dλ vs Wavelength
dn/dλ Calculator
Abbe Number Calculator
Transmission vs Wavelength
Transmission Calculator
Optical Properties
| Refractive Index (nd) | — |
|---|---|
| Abbe Number (Vd) | — |
| Dispersion Formula | Sellmeier |
| Wavelength Range | 0.6 — 12.5 µm |
$$n(\lambda) = \sqrt{1 + \frac{1.4005\,\lambda^2}{\lambda^2 - 0} + \frac{3.4429\,\lambda^2}{\lambda^2 - 0.0871} + \frac{1.0394\,\lambda^2}{\lambda^2 - 805.5}}$$
Thermal Properties
| TCE -30/70°C (10-6/K) | 21.0 |
|---|---|
| TCE 100/300°C (10-6/K) | — |
| Thermal Conductivity (W/mK) | — |
| Heat Capacity (J/gK) | — |
$$\frac{dn}{dT} = \frac{n_0^2 - 1}{2\,n_0}\left[-3.89 \times 10^{-6} + 2(0)\,\Delta T + 3(0)\,\Delta T^2 + \frac{1.77 \times 10^{-5} + 2(0)\,\Delta T}{\lambda - 0.246}\right]
\Delta T = T - T_0, \quad T_0 = 22\,°\text{C}$$
Physical Properties
| Density (g/cm³) | 3.2 |
|---|---|
| Relative Cost | — |
Mechanical Properties
| Young's Modulus (GPa) | — |
|---|---|
| Poisson's Ratio | — |
| Knoop Hardness (kgf/mm²) | — |
Chemical Resistance
| Climatic Resistance | — |
|---|---|
| Stain Resistance | — |
| Acid Resistance | — |
| Alkali Resistance | — |
| Phosphate Resistance | — |
Notes
Melted frequently and additionally as required