K-SFLD4 by Sumita
Standard
Rare
Environmentally Friendly
K-SFLD4 by Sumita is a standard optical glass with a rare melt frequency. It transmits from 0.36 to 2.00 µm with an nd of 1.7552 and a Vd of 27.5. It has medium thermal expansion (CTE of 8.6×10⁻⁶/K) and excellent 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) | 8.6 |
|---|---|
| TCE 100/300°C (10-6/K) | 9.1 |
| Thermal Conductivity (W/mK) | — |
| Heat Capacity (J/gK) | — |
$$\frac{dn}{dT} = \frac{n_0^2 - 1}{2\,n_0}\left[-2.91 \times 10^{-6} + 2(1.97 \times 10^{-8})\,\Delta T + 3(-3.23 \times 10^{-10})\,\Delta T^2 + \frac{8.95 \times 10^{-7} + 2(9.72 \times 10^{-10})\,\Delta T}{\lambda - 0.291}\right]
\Delta T = T - T_0, \quad T_0 = 20\,°\text{C}$$
Chemical Resistance
| Climatic Resistance | 1 |
|---|---|
| Stain Resistance | — |
| Acid Resistance | 1 |
| Alkali Resistance | — |
| Phosphate Resistance | — |
Similar Glasses (Other Manufacturers)
| Glass | Manufacturer | nd | Vd | Compare |
|---|---|---|---|---|
| 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 |