SFL4 by Schott
Obsolete
Unknown
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) | 1.7552 |
|---|---|
| Abbe Number (Vd) | 27.206054 |
| Dispersion Formula | Sellmeier |
| Wavelength Range | 0.334 — 1.06 µm |
$$n(\lambda) = \sqrt{1 + \frac{1.68435\,\lambda^2}{\lambda^2 - 0.0128694} + \frac{0.275878\,\lambda^2}{\lambda^2 - 0.06098} + \frac{1.80248\,\lambda^2}{\lambda^2 - 159.614}}$$
Thermal Properties
| TCE -30/70°C (10-6/K) | 9.2 |
|---|---|
| TCE 100/300°C (10-6/K) | 10.8 |
| Thermal Conductivity (W/mK) | — |
| Heat Capacity (J/gK) | — |
$$\frac{dn}{dT} = \frac{n_0^2 - 1}{2\,n_0}\left[-4.9 \times 10^{-6} + 2(8.17 \times 10^{-9})\,\Delta T + 3(-1.71 \times 10^{-11})\,\Delta T^2 + \frac{9.93 \times 10^{-7} + 2(1.45 \times 10^{-9})\,\Delta T}{\lambda - 0.281}\right]
\Delta T = T - T_0, \quad T_0 = 20\,°\text{C}$$
Physical Properties
| Density (g/cm³) | 3.37 |
|---|---|
| Relative Cost | 8.28 |
Mechanical Properties
| Young's Modulus (GPa) | — |
|---|---|
| Poisson's Ratio | — |
| Knoop Hardness (kgf/mm²) | — |
Chemical Resistance
| Climatic Resistance | — |
|---|---|
| Stain Resistance | 0 |
| Acid Resistance | 1 |
| Alkali Resistance | 1 |
| Phosphate Resistance | — |
Notes
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