PFK85 by Sumita

Obsolete Very Rare Environmentally Dangerous
Refractive Index vs Wavelength
Refractive Index Calculator
Valid range: 0.27–2.0 µm
dn/dλ vs Wavelength
dn/dλ Calculator
Valid range: 0.27–2.0 µm
Abbe Number Calculator
Transmission vs Wavelength
Transmission Calculator
Valid wavelength range: 0.280–2.000 µm
Optical Properties
Refractive Index (nd) 1.48563
Abbe Number (Vd) 85.2
Dispersion Formula Schott
Wavelength Range 0.27 — 2.0 µm
$$n(\lambda) = \sqrt{2.1853 - 0.00472503\,\lambda^2 + 0.00784216\,\lambda^{-2} + 8.58344 \times 10^{-5}\,\lambda^{-4} - 5.37792 \times 10^{-7}\,\lambda^{-6} + 6.67976 \times 10^{-8}\,\lambda^{-8}}$$
Thermal Properties
TCE -30/70°C (10-6/K)
TCE 100/300°C (10-6/K) 16.3
Thermal Conductivity (W/mK)
Heat Capacity (J/gK)
$$\frac{dn}{dT} = \frac{n_0^2 - 1}{2\,n_0}\left[0 + 2(0)\,\Delta T + 3(0)\,\Delta T^2 + \frac{0 + 2(0)\,\Delta T}{\lambda - 0}\right] \Delta T = T - T_0, \quad T_0 = 20\,°\text{C}$$
Physical Properties
Density (g/cm³) 3.97
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
FCD915 Hoya 1.48071 85.29
ULTRAN20 Schott 1.486561 84.473976
A87-84 Corning 1.486561 84.473232
N-FK51 Schott 1.48656 84.47
N-FK51A Schott 1.48656 84.47
FK51 Schott 1.486561 84.467994
A86-82 Corning 1.486052 81.814538
FK52 Schott 1.486052 81.802215
N-PK52 Schott 1.497005 81.633263
BAF2 Generic IR 1.474478 81.607872
Similar Glasses (Sumita)
Glass Manufacturer nd Vd
K-PFK85 Sumita 1.48563 85.2
K-PFK85(M) Sumita 1.48375 85.0
K-PFK80 Sumita 1.497 81.5
PFK80 Sumita 1.497 81.5
K-PFK80(M) Sumita 1.49533 80.8
K-PFK90(M) Sumita 1.45733 89.8
K-PFK90 Sumita 1.4588 90.0
CAFK95 Sumita 1.43425 95.0
K-CaFK95 Sumita 1.43425 95.0
K-CaFK95(M) Sumita 1.43312 95.0
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