K-VC78 by Sumita

Standard Medium Precision Molding Environmentally Friendly
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: 0.270–2.000 µm
Optical Properties
Refractive Index (nd) 1.66955
Abbe Number (Vd) 55.4
Dispersion Formula Schott
Wavelength Range 0.36 — 1.55 µm
$$n(\lambda) = \sqrt{2.73769 - 0.0122692\,\lambda^2 + 0.0174394\,\lambda^{-2} + 0.000470887\,\lambda^{-4} - 2.71501 \times 10^{-5}\,\lambda^{-6} + 1.8172 \times 10^{-6}\,\lambda^{-8}}$$
Thermal Properties
TCE -30/70°C (10-6/K) 8.0
TCE 100/300°C (10-6/K) 10.0
Thermal Conductivity (W/mK)
Heat Capacity (J/gK)
$$\frac{dn}{dT} = \frac{n_0^2 - 1}{2\,n_0}\left[-1 \times 10^{-6} + 2(1.6 \times 10^{-8})\,\Delta T + 3(-1.38 \times 10^{-10})\,\Delta T^2 + \frac{5.07 \times 10^{-7} + 2(3.13 \times 10^{-10})\,\Delta T}{\lambda - 0.19}\right] \Delta T = T - T_0, \quad T_0 = 20\,°\text{C}$$
Physical Properties
Density (g/cm³) 3.44
Relative Cost
Mechanical Properties
Young's Modulus (GPa)
Poisson's Ratio
Knoop Hardness (kgf/mm²)
Chemical Resistance
Climatic Resistance 1
Stain Resistance
Acid Resistance 4
Alkali Resistance
Phosphate Resistance
Similar Glasses (Other Manufacturers)
Glass Manufacturer nd Vd
D-LAK70 CDGM 1.6691 55.389689
D-LAK70-25 CDGM 1.668 55.295752
H-LAK11 CDGM 1.66461 54.612239
S-LAL12Q Ohara 1.6779 55.346888
S-LAL12 Ohara 1.6779 55.341195
LAL12 Ohara 1.6779 55.337587
H-LAK5A CDGM 1.6779 55.51497
LAC12 Hoya 1.6779 55.52
N-LAK12 Schott 1.6779 55.2
LAKN12 Schott 1.6779 55.199566
Similar Glasses (Sumita)
Glass Manufacturer nd Vd
VC78 Sumita 1.6691 55.4
K-VC78(M) Sumita 1.66624 55.1
LAK12 Sumita 1.6779 55.5
K-LaK12 Sumita 1.6779 55.5
K-LaKn4 Sumita 1.671 57.2
LAKN4 Sumita 1.671 57.2
LAKN9 Sumita 1.678 53.3
K-LaK11 Sumita 1.6583 57.3
LAK11 Sumita 1.6583 57.3
K-LaKn11 Sumita 1.6583 53.4
Compare Glasses