SK7 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) | 1.60729 |
|---|---|
| Abbe Number (Vd) | 59.5 |
| Dispersion Formula | Schott |
| Wavelength Range | 0.27 — 2.0 µm |
$$n(\lambda) = \sqrt{2.5409 - 0.00926875\,\lambda^2 + 0.0157149\,\lambda^{-2} - 8.88003 \times 10^{-5}\,\lambda^{-4} + 4.32874 \times 10^{-5}\,\lambda^{-6} - 1.98993 \times 10^{-6}\,\lambda^{-8}}$$
Thermal Properties
| TCE -30/70°C (10-6/K) | — |
|---|---|
| TCE 100/300°C (10-6/K) | 7.1 |
| 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) | 3.47 |
|---|---|
| Relative Cost | — |
Mechanical Properties
| Young's Modulus (GPa) | — |
|---|---|
| Poisson's Ratio | — |
| Knoop Hardness (kgf/mm²) | — |
Chemical Resistance
| Climatic Resistance | 2 |
|---|---|
| Stain Resistance | — |
| Acid Resistance | 5 |
| Alkali Resistance | — |
| Phosphate Resistance | — |
Similar Glasses (Other Manufacturers)
| Glass | Manufacturer | nd | Vd | |
|---|---|---|---|---|
| BACD7 | Hoya | 1.607292 | 59.474776 | |
| SK7 | Schott | 1.60729 | 59.459272 | |
| BSM7 | Ohara | 1.607291 | 59.375631 | |
| C09-59 | Corning | 1.608756 | 59.036803 | |
| SK3 | Schott | 1.60881 | 58.921505 | |
| BACD3 | Hoya | 1.608812 | 58.863994 | |
| H-ZK4 | CDGM | 1.60881 | 58.855991 | |
| BSM4 | Ohara | 1.612716 | 58.749129 | |
| S-BSM4 | Ohara | 1.612716 | 58.716945 | |
| N-SK4 | Schott | 1.61272 | 58.63 |