LAK8 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: 0.310–2.000 µm
Optical Properties
Refractive Index (nd) 1.713
Abbe Number (Vd) 53.9
Dispersion Formula Schott
Wavelength Range 0.27 — 2.0 µm
$$n(\lambda) = \sqrt{2.8792 - 0.0146914\,\lambda^2 + 0.0196349\,\lambda^{-2} + 0.000403651\,\lambda^{-4} - 1.29366 \times 10^{-6}\,\lambda^{-6} + 2.29972 \times 10^{-7}\,\lambda^{-8}}$$
Thermal Properties
TCE -30/70°C (10-6/K)
TCE 100/300°C (10-6/K) 7.5
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) 3.79
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
S-LAL8 Ohara 1.712995 53.867058
LAC8 Hoya 1.713 53.94
M-LAC8 Hoya 1.713 53.94
LAL8 Ohara 1.712995 53.845848
D13-54 Corning 1.713 53.843096
MP-LAC8-30 Hoya 1.7133 53.95
H-LAK7A CDGM 1.713 53.832974
LAK8 Schott 1.713003 53.831633
N-LAK8 Schott 1.713 53.83
LAL60 Ohara 1.725999 53.565698
Similar Glasses (Sumita)
Glass Manufacturer nd Vd
K-LaK8 Sumita 1.713 53.9
K-LaK18 Sumita 1.72916 54.7
LAK18 Sumita 1.72916 54.7
LAK13 Sumita 1.6935 53.4
K-VC80 Sumita 1.69384 53.1
LAK14 Sumita 1.6968 55.6
K-LaK14 Sumita 1.6968 55.6
LAK9 Sumita 1.691 54.8
K-LaK9 Sumita 1.691 54.8
K-VC80(M) Sumita 1.68983 52.9
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