SF4W by Sumita
Obsolete
Very Rare
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) | 27.5 |
| Dispersion Formula | Schott |
| Wavelength Range | 0.27 — 2.0 µm |
$$n(\lambda) = \sqrt{2.96129 - 0.00971846\,\lambda^2 + 0.0367462\,\lambda^{-2} + 0.00212176\,\lambda^{-4} - 0.000106827\,\lambda^{-6} + 1.62875 \times 10^{-5}\,\lambda^{-8}}$$
Thermal Properties
| TCE -30/70°C (10-6/K) | — |
|---|---|
| TCE 100/300°C (10-6/K) | 8.5 |
| Thermal Conductivity (W/mK) | — |
| Heat Capacity (J/gK) | — |
$$\frac{dn}{dT} = \frac{n_0^2 - 1}{2\,n_0}\left[0 + 2(0)\,\Delta T + 3(0)\,\Delta T^2 + \frac{0 + 2(0)\,\Delta T}{\lambda - 0}\right]
\Delta T = T - T_0, \quad T_0 = 20\,°\text{C}$$
Physical Properties
| Density (g/cm³) | 4.78 |
|---|---|
| Relative Cost | — |
Mechanical Properties
| Young's Modulus (GPa) | — |
|---|---|
| Poisson's Ratio | — |
| Knoop Hardness (kgf/mm²) | — |
Chemical Resistance
| Climatic Resistance | 1 |
|---|---|
| Stain Resistance | — |
| Acid Resistance | 2 |
| Alkali Resistance | — |
| Phosphate Resistance | — |
Similar Glasses (Other Manufacturers)
| Glass | Manufacturer | nd | Vd | |
|---|---|---|---|---|
| S-TIH4 | Ohara | 1.755199 | 27.512089 | |
| PBH4 | Ohara | 1.755199 | 27.512146 | |
| PBH4W | Ohara | 1.755199 | 27.512146 | |
| E-FD4L | Hoya | 1.7552 | 27.53 | |
| E-FD4 | Hoya | 1.7552 | 27.53 | |
| H-ZF6 | CDGM | 1.7552 | 27.530047 | |
| FD4 | Hoya | 1.755199 | 27.530242 | |
| ZF6 | CDGM | 1.755205 | 27.546239 | |
| SF4 | Schott | 1.7552 | 27.58 | |
| D56-27 | Corning | 1.755203 | 27.591377 |