K-SK18RH by Sumita
Standard
Medium
Environmentally Friendly
K-SK18RH by Sumita is a standard optical glass with a medium melt frequency. It transmits from 0.30 to 2.00 µm with an nd of 1.63854 and a Vd of 55.5. It has medium thermal expansion (CTE of 6.7×10⁻⁶/K) and good chemical resistance.
Refractive Index vs Wavelength
Refractive Index Calculator
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) | 6.7 |
|---|---|
| TCE 100/300°C (10-6/K) | 8.4 |
| Thermal Conductivity (W/mK) | — |
| Heat Capacity (J/gK) | — |
$$\frac{dn}{dT} = \frac{n_0^2 - 1}{2\,n_0}\left[1.1 \times 10^{-6} + 2(1.41 \times 10^{-8})\,\Delta T + 3(-2.56 \times 10^{-10})\,\Delta T^2 + \frac{4.99 \times 10^{-7} + 2(4.12 \times 10^{-10})\,\Delta T}{\lambda - 0.193}\right]
\Delta T = T - T_0, \quad T_0 = 20\,°\text{C}$$
Chemical Resistance
| Climatic Resistance | 1 |
|---|---|
| Stain Resistance | — |
| Acid Resistance | 3 |
| Alkali Resistance | — |
| Phosphate Resistance | — |
Similar Glasses (Other Manufacturers)
| Glass | Manufacturer | nd | Vd | Compare |
|---|---|---|---|---|
| C39-56 | Corning | 1.638505 | 55.504447 | |
| BACD18 | Hoya | 1.63854 | 55.45 | |
| H-ZK11 | CDGM | 1.63854 | 55.446553 | |
| N-SK18 | Schott | 1.63854 | 55.423596 | |
| SK18A | Schott | 1.63854 | 55.423596 | |
| BSM18 | Ohara | 1.638539 | 55.384768 | |
| S-BSM18 | Ohara | 1.638539 | 55.380028 | |
| M-PCD55AR | Hoya | 1.63858 | 55.18 | |
| MP-PCD55AR | Hoya | 1.63858 | 55.18 | |
| LACL1 | Hoya | 1.640851 | 56.835319 |