K-PSFn185(M) by Sumita

Standard Rare Environmentally Friendly

K-PSFn185(M) by Sumita is a standard optical glass with a rare melt frequency. It transmits from 0.35 to 2.00 µm with an nd of 1.84524 and a Vd of 27.1. It has medium thermal expansion (CTE of 8.5×10⁻⁶/K) and excellent chemical resistance.

Refractive Index vs Wavelength
Refractive Index Calculator
Valid range: 0.4–1.55 µm
dn/dλ vs Wavelength
dn/dλ Calculator
Valid range: 0.4–1.55 µm
Abbe Number Calculator
Transmission vs Wavelength
Transmission Calculator
Valid wavelength range: 0.350–2.000 µm
Optical Properties
Refractive Index (nd) 1.84524
Abbe Number (Vd) 27.1
Dispersion Formula Schott
Wavelength Range 0.4 — 1.55 µm
$$n(\lambda) = \sqrt{3.26502 - 0.0137027\,\lambda^2 + 0.0435737\,\lambda^{-2} + 0.00218051\,\lambda^{-4} - 4.47458 \times 10^{-5}\,\lambda^{-6} + 1.73299 \times 10^{-5}\,\lambda^{-8}}$$
Thermal Properties
TCE -30/70°C (10-6/K) 8.5
TCE 100/300°C (10-6/K) 10.1
Thermal Conductivity (W/mK) —
Heat Capacity (J/gK) —
$$\frac{dn}{dT} = \frac{n_0^2 - 1}{2\,n_0}\left[-7.95 \times 10^{-6} + 2(1.17 \times 10^{-8})\,\Delta T + 3(-2.57 \times 10^{-10})\,\Delta T^2 + \frac{8.33 \times 10^{-7} + 2(1.16 \times 10^{-9})\,\Delta T}{\lambda - 0.3}\right] \Delta T = T - T_0, \quad T_0 = 20\,°\text{C}$$
Physical Properties
Density (g/cm³) 4.17
Relative Cost —
Mechanical Properties
Young's Modulus (GPa) —
Poisson's Ratio —
Knoop Hardness (kgf/mm²) —
Chemical Resistance
Climatic Resistance 1
Stain Resistance —
Acid Resistance 1
Alkali Resistance —
Phosphate Resistance —
Similar Glasses (Other Manufacturers)
Glass Manufacturer nd Vd Compare
NBFD26 Hoya 1.83401 25.97
NBFD25 Hoya 1.85451 25.15
PBH56 Ohara 1.84139 24.559059
S-NBH56 Ohara 1.854779 24.79898
H-ZLAF76A CDGM 1.85013 30.012319
S-NBH57 Ohara 1.850249 30.046429
H-ZLAF76 CDGM 1.85013 30.055517
PBH55 Ohara 1.84986 24.054274
PBH53 Ohara 1.846658 23.885544
PBH53W Ohara 1.846658 23.885544
Similar Glasses (Sumita)
Glass Manufacturer nd Vd Compare
K-PSFn185 Sumita 1.8507 26.9
K-PSFn4 Sumita 1.844 24.8
K-PSFn4(M) Sumita 1.83932 24.8
SFN3 Sumita 1.84666 23.9
SFLDN3 Sumita 1.84666 23.9
K-PSFn3 Sumita 1.83917 23.9
K-SFLDn3 Sumita 1.8467 23.8
K-SFLDn3W Sumita 1.8467 23.8
K-PSFn3(M) Sumita 1.83352 24.0
SFLD20 Sumita 1.81786 23.7
Compare Glasses
    Compare Selected