LAKN13 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: 0.320–2.000 µm
Optical Properties
Refractive Index (nd) 1.641
Abbe Number (Vd) 56.8
Dispersion Formula Schott
Wavelength Range 0.27 — 2.0 µm
$$n(\lambda) = \sqrt{2.64636 - 0.0103544\,\lambda^2 + 0.0164985\,\lambda^{-2} + 0.000265361\,\lambda^{-4} + 3.01588 \times 10^{-6}\,\lambda^{-6} + 1.04236 \times 10^{-7}\,\lambda^{-8}}$$
Thermal Properties
TCE -30/70°C (10-6/K)
TCE 100/300°C (10-6/K) 8.1
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) 3.71
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
LACL1 Hoya 1.640851 56.835319
S-BSM93 Ohara 1.640998 56.927542
BSM93 Ohara 1.640998 56.927542
LAC6 Hoya 1.642498 57.959359
LAKN6 Schott 1.642499 57.962061
C42-58 Corning 1.642502 58.061633
C39-56 Corning 1.638505 55.504447
BACD18 Hoya 1.63854 55.45
H-ZK11 CDGM 1.63854 55.446553
SK18A Schott 1.63854 55.423596
Similar Glasses (Sumita)
Glass Manufacturer nd Vd
K-LaK6 Sumita 1.6425 58.1
LAK6 Sumita 1.6425 58.1
K-SK18RH Sumita 1.63854 55.5
K-SK18 Sumita 1.63854 55.5
SK18 Sumita 1.63854 55.5
SK18RH Sumita 1.63854 55.5
K-LaKn5 Sumita 1.65 55.8
LAKN5 Sumita 1.65 55.8
LAK7 Sumita 1.6516 58.3
K-LaK7 Sumita 1.6516 58.3
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