SF8 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) | 1.688932 |
|---|---|
| Abbe Number (Vd) | 31.176063 |
| Dispersion Formula | Sellmeier |
| Wavelength Range | 0.334 — 2.5 µm |
$$n(\lambda) = \sqrt{1 + \frac{1.49514\,\lambda^2}{\lambda^2 - 0.011499} + \frac{0.26253\,\lambda^2}{\lambda^2 - 0.051717} + \frac{0.969568\,\lambda^2}{\lambda^2 - 113.459}}$$
Thermal Properties
| TCE -30/70°C (10-6/K) | 8.2 |
|---|---|
| TCE 100/300°C (10-6/K) | 9.0 |
| Thermal Conductivity (W/mK) | — |
| Heat Capacity (J/gK) | — |
$$\frac{dn}{dT} = \frac{n_0^2 - 1}{2\,n_0}\left[3.7 \times 10^{-6} + 2(1.72 \times 10^{-8})\,\Delta T + 3(-4.66 \times 10^{-11})\,\Delta T^2 + \frac{1.27 \times 10^{-6} + 2(1.19 \times 10^{-9})\,\Delta T}{\lambda - 0.254}\right]
\Delta T = T - T_0, \quad T_0 = 20\,°\text{C}$$
Physical Properties
| Density (g/cm³) | 4.22 |
|---|---|
| Relative Cost | 2.25 |
Mechanical Properties
| Young's Modulus (GPa) | — |
|---|---|
| Poisson's Ratio | — |
| Knoop Hardness (kgf/mm²) | — |
Chemical Resistance
| Climatic Resistance | 1 |
|---|---|
| Stain Resistance | 1 |
| Acid Resistance | 2 |
| Alkali Resistance | 2 |
| Phosphate Resistance | 2 |
Notes
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Similar Glasses (Other Manufacturers)
| Glass | Manufacturer | nd | Vd | |
|---|---|---|---|---|
| ZF10 | CDGM | 1.688934 | 31.184753 | |
| H-ZF10 | CDGM | 1.68893 | 31.16057 | |
| MP-FD80 | Hoya | 1.68893 | 31.16 | |
| E-FD8 | Hoya | 1.68893 | 31.16 | |
| M-FD80 | Hoya | 1.68893 | 31.16 | |
| MC-FD80 | Hoya | 1.68893 | 31.16 | |
| FD8 | Hoya | 1.688931 | 31.158857 | |
| SF8 | Sumita | 1.68893 | 31.2 | |
| K-SFLD8W | Sumita | 1.6891 | 31.2 | |
| C89-31 | Corning | 1.689004 | 31.210861 |