K-PSFn4(M) by Sumita

Obsolete Very Rare Environmentally Friendly

K-PSFn4(M) by Sumita is an obsolete optical glass with a very rare melt frequency. It transmits from 0.36 to 2.00 µm with an nd of 1.83932 and a Vd of 24.8. It has medium thermal expansion (CTE of 10.3×10⁻⁶/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: 0.360–2.000 µm
Optical Properties
Refractive Index (nd) 1.83932
Abbe Number (Vd) 24.8
Dispersion Formula Schott
Wavelength Range 0.4 — 1.55 µm
$$n(\lambda) = \sqrt{3.2299 - 0.0113892\,\lambda^2 + 0.0471924\,\lambda^{-2} + 0.00244871\,\lambda^{-4} - 6.48867 \times 10^{-5}\,\lambda^{-6} + 2.10451 \times 10^{-5}\,\lambda^{-8}}$$
Thermal Properties
TCE -30/70°C (10-6/K) 10.3
TCE 100/300°C (10-6/K) 12.2
Thermal Conductivity (W/mK) —
Heat Capacity (J/gK) —
$$\frac{dn}{dT} = \frac{n_0^2 - 1}{2\,n_0}\left[-4.02 \times 10^{-6} + 2(2.01 \times 10^{-8})\,\Delta T + 3(-1.33 \times 10^{-10})\,\Delta T^2 + \frac{1.73 \times 10^{-6} + 2(1.55 \times 10^{-9})\,\Delta T}{\lambda - 0.277}\right] \Delta T = T - T_0, \quad T_0 = 20\,°\text{C}$$
Physical Properties
Density (g/cm³) 4.58
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
PBH56 Ohara 1.84139 24.559059
PBH53W Ohara 1.846658 23.885544
PBH53 Ohara 1.846658 23.885544
S-NPH53 Ohara 1.84666 23.88395
NBFD26 Hoya 1.83401 25.97
FDS90-SGP Hoya 1.84666 23.84
SF57HT Schott 1.84666 23.83
SF57HTultra Schott 1.84666 23.83
SF57 Schott 1.84666 23.83
FDS9 Hoya 1.846658 23.826345
Similar Glasses (Sumita)
Glass Manufacturer nd Vd Compare
K-PSFn4 Sumita 1.844 24.8
K-PSFn3 Sumita 1.83917 23.9
K-PSFn3(M) Sumita 1.83352 24.0
SFLDN3 Sumita 1.84666 23.9
SFN3 Sumita 1.84666 23.9
K-SFLDn3W Sumita 1.8467 23.8
K-SFLDn3 Sumita 1.8467 23.8
K-PSFn185(M) Sumita 1.84524 27.1
K-PSFn185 Sumita 1.8507 26.9
SFLD20 Sumita 1.81786 23.7
Compare Glasses
    Compare Selected