K-VC90(M) by Sumita

Standard Rare Environmentally Friendly

K-VC90(M) by Sumita is a standard optical glass with a rare melt frequency. It transmits from 0.33 to 2.00 µm with an nd of 1.84859 and a Vd of 38.9. It has medium thermal expansion (CTE of 7.7×10⁻⁶/K) and good chemical resistance.

Refractive Index vs Wavelength
Refractive Index Calculator
Valid range: 0.36–1.55 µm
dn/dλ vs Wavelength
dn/dλ Calculator
Valid range: 0.36–1.55 µm
Abbe Number Calculator
Transmission vs Wavelength
Transmission Calculator
Valid wavelength range: 0.330–2.000 µm
Optical Properties
Refractive Index (nd) 1.84859
Abbe Number (Vd) 38.9
Dispersion Formula Schott
Wavelength Range 0.36 — 1.55 µm
$$n(\lambda) = \sqrt{3.31495 - 0.013619\,\lambda^2 + 0.0338427\,\lambda^{-2} + 0.00110887\,\lambda^{-4} - 2.81106 \times 10^{-5}\,\lambda^{-6} + 5.11202 \times 10^{-6}\,\lambda^{-8}}$$
Thermal Properties
TCE -30/70°C (10-6/K) 7.7
TCE 100/300°C (10-6/K) 9.4
Thermal Conductivity (W/mK) —
Heat Capacity (J/gK) —
$$\frac{dn}{dT} = \frac{n_0^2 - 1}{2\,n_0}\left[4.39 \times 10^{-7} + 2(1.31 \times 10^{-8})\,\Delta T + 3(-1.78 \times 10^{-10})\,\Delta T^2 + \frac{7.82 \times 10^{-7} + 2(9.78 \times 10^{-10})\,\Delta T}{\lambda - 0.232}\right] \Delta T = T - T_0, \quad T_0 = 20\,°\text{C}$$
Physical Properties
Density (g/cm³) 4.98
Relative Cost —
Mechanical Properties
Young's Modulus (GPa) —
Poisson's Ratio —
Knoop Hardness (kgf/mm²) —
Chemical Resistance
Climatic Resistance 1
Stain Resistance —
Acid Resistance 2
Alkali Resistance —
Phosphate Resistance —
Similar Glasses (Other Manufacturers)
Glass Manufacturer nd Vd Compare
D-ZLAF85A-25 CDGM 1.8511 40.055609
MC-TAFD315 Hoya 1.85135 40.07
M-TAFD315 Hoya 1.85135 40.07
MP-TAFD305 Hoya 1.85135 40.1
MC-TAFD305 Hoya 1.85135 40.1
M-TAFD305 Hoya 1.85135 40.1
D-ZLAF85LN CDGM 1.84558 40.094322
D-ZLAF85LN-25 CDGM 1.84443 40.067973
D-ZLAF85A CDGM 1.85222 40.10819
L-LAH85V Ohara 1.854 40.378368
Similar Glasses (Sumita)
Glass Manufacturer nd Vd Compare
K-VC90 Sumita 1.8528 39.0
K-VC185(M) Sumita 1.84909 40.5
K-VC185 Sumita 1.85375 40.6
K-LaSFn14 Sumita 1.834 37.3
LASFN14 Sumita 1.834 37.2
K-VC99(M) Sumita 1.84604 41.5
K-VC99 Sumita 1.8506 41.6
LASFN13 Sumita 1.863 41.6
LASFN8 Sumita 1.835 42.7
K-LaSFn8 Sumita 1.835 42.7
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