K-LaSFn6 by Sumita

Standard Rare Environmentally Friendly

K-LaSFn6 by Sumita is a standard optical glass with a rare melt frequency. It transmits from 0.31 to 2.00 µm with an nd of 1.804 and a Vd of 46.6. It has low thermal expansion (CTE of 5.9×10⁻⁶/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: 0.310–2.000 µm
Optical Properties
Refractive Index (nd) 1.804
Abbe Number (Vd) 46.6
Dispersion Formula Schott
Wavelength Range 0.36 — 1.55 µm
$$n(\lambda) = \sqrt{3.1766 - 0.0152146\,\lambda^2 + 0.0266744\,\lambda^{-2} + 0.000746745\,\lambda^{-4} - 2.63508 \times 10^{-5}\,\lambda^{-6} + 2.7515 \times 10^{-6}\,\lambda^{-8}}$$
Thermal Properties
TCE -30/70°C (10-6/K) 5.9
TCE 100/300°C (10-6/K) 7.4
Thermal Conductivity (W/mK) —
Heat Capacity (J/gK) —
$$\frac{dn}{dT} = \frac{n_0^2 - 1}{2\,n_0}\left[1.72 \times 10^{-6} + 2(1.48 \times 10^{-8})\,\Delta T + 3(-1.94 \times 10^{-10})\,\Delta T^2 + \frac{5.94 \times 10^{-7} + 2(9.48 \times 10^{-10})\,\Delta T}{\lambda - 0.205}\right] \Delta T = T - T_0, \quad T_0 = 20\,°\text{C}$$
Physical Properties
Density (g/cm³) 4.72
Relative Cost —
Mechanical Properties
Young's Modulus (GPa) —
Poisson's Ratio —
Knoop Hardness (kgf/mm²) —
Chemical Resistance
Climatic Resistance 1
Stain Resistance —
Acid Resistance 3
Alkali Resistance —
Phosphate Resistance —
Similar Glasses (Other Manufacturers)
Glass Manufacturer nd Vd Compare
S-LAH65V Ohara 1.803999 46.583432
LAH65 Ohara 1.804 46.575911
H-ZLAF50D CDGM 1.804 46.575016
H-ZLAF50E CDGM 1.804 46.574487
S-LAH65 Ohara 1.804 46.570373
S-LAH65VS Ohara 1.804 46.527532
N-LASF44 Schott 1.8042 46.5
TAF3 Hoya 1.8042 46.5
TAF3D Hoya 1.8042 46.5
H-ZLAF2A CDGM 1.80279 46.761307
Similar Glasses (Sumita)
Glass Manufacturer nd Vd Compare
LASFN6 Sumita 1.80235 46.7
K-LaSFn9 Sumita 1.816 46.7
LASFN9 Sumita 1.816 46.7
LASFN19 Sumita 1.795 45.2
K-LaSFn16 Sumita 1.7883 47.4
LASFN16 Sumita 1.7883 47.4
K-LaSFn10 Sumita 1.8155 44.4
LASFN10 Sumita 1.8155 44.4
K-VC100 Sumita 1.804 43.6
K-VC100(M) Sumita 1.79916 43.5
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