LAKN4 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) 1.671
Abbe Number (Vd) 57.2
Dispersion Formula Schott
Wavelength Range 0.27 — 2.0 µm
$$n(\lambda) = \sqrt{2.7439 - 0.0124397\,\lambda^2 + 0.0173187\,\lambda^{-2} + 0.000300187\,\lambda^{-4} - 2.63882 \times 10^{-6}\,\lambda^{-6} + 4.31361 \times 10^{-7}\,\lambda^{-8}}$$
Thermal Properties
TCE -30/70°C (10-6/K)
TCE 100/300°C (10-6/K) 8.5
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) 3.88
Relative Cost
Mechanical Properties
Young's Modulus (GPa)
Poisson's Ratio
Knoop Hardness (kgf/mm²)
Chemical Resistance
Climatic Resistance 2
Stain Resistance
Acid Resistance 5
Alkali Resistance
Phosphate Resistance
Similar Glasses (Other Manufacturers)
Glass Manufacturer nd Vd
LACL7 Hoya 1.669996 57.308358
LAL52 Ohara 1.669999 57.327972
S-LAL52 Ohara 1.669999 57.327972
LAK23 Schott 1.668816 57.38444
H-LAK1 CDGM 1.6595 57.34726
LAK11 Schott 1.658302 57.261599
LAC11 Hoya 1.658296 57.262085
S-LAL11 Ohara 1.658296 57.332589
LAL11 Ohara 1.658296 57.332589
D-LAK70 CDGM 1.6691 55.389689
Similar Glasses (Sumita)
Glass Manufacturer nd Vd
K-LaKn4 Sumita 1.671 57.2
LAK11 Sumita 1.6583 57.3
K-LaK11 Sumita 1.6583 57.3
K-VC78 Sumita 1.66955 55.4
VC78 Sumita 1.6691 55.4
K-LaK12 Sumita 1.6779 55.5
LAK12 Sumita 1.6779 55.5
K-VC78(M) Sumita 1.66624 55.1
K-LaFK55(M) Sumita 1.68875 55.8
K-LaK7 Sumita 1.6516 58.3
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