K-SSK4 by Sumita
Standard
Rare
Environmentally Friendly
K-SSK4 by Sumita is a standard optical glass with a rare melt frequency. It transmits from 0.27 to 2.00 µm with an nd of 1.61765 and a Vd of 55.1. It has medium thermal expansion (CTE of 7.1×10⁻⁶/K) and average chemical resistance.
Refractive Index vs Wavelength
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dn/dλ vs Wavelength
dn/dλ Calculator
Abbe Number Calculator
Transmission vs Wavelength
Transmission Calculator
Optical Properties
Thermal Properties
| TCE -30/70°C (10-6/K) | 7.1 |
|---|---|
| TCE 100/300°C (10-6/K) | 8.4 |
| Thermal Conductivity (W/mK) | — |
| Heat Capacity (J/gK) | — |
$$\frac{dn}{dT} = \frac{n_0^2 - 1}{2\,n_0}\left[1.84 \times 10^{-6} + 2(1.42 \times 10^{-8})\,\Delta T + 3(-1.94 \times 10^{-10})\,\Delta T^2 + \frac{5.13 \times 10^{-7} + 2(7.12 \times 10^{-10})\,\Delta T}{\lambda - 0.198}\right]
\Delta T = T - T_0, \quad T_0 = 20\,°\text{C}$$
Chemical Resistance
| Climatic Resistance | 2 |
|---|---|
| Stain Resistance | — |
| Acid Resistance | 4 |
| Alkali Resistance | — |
| Phosphate Resistance | — |
Similar Glasses (Other Manufacturers)
| Glass | Manufacturer | nd | Vd | Compare |
|---|---|---|---|---|
| C17-55 | Corning | 1.617605 | 55.123455 | |
| SSK4A | Schott | 1.61765 | 55.141867 | |
| BSM24 | Ohara | 1.617646 | 55.049782 | |
| BACED4 | Hoya | 1.617652 | 55.15751 | |
| H-ZK8 | CDGM | 1.61405 | 55.116283 | |
| BACD9 | Hoya | 1.614047 | 55.118097 | |
| S-BSM9 | Ohara | 1.614047 | 54.990097 | |
| BSM9 | Ohara | 1.614047 | 54.971106 | |
| S-BSM21 | Ohara | 1.617195 | 54.062144 | |
| BSM21 | Ohara | 1.617196 | 54.040511 |