K-LaSFn10 by Sumita

Standard Rare Environmentally Friendly

K-LaSFn10 by Sumita is a standard optical glass with a rare melt frequency. It transmits from 0.34 to 2.00 µm with an nd of 1.8155 and a Vd of 44.4. It has low thermal expansion (CTE of 5.6×10⁻⁶/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: 0.340–2.000 µm
Optical Properties
Refractive Index (nd) 1.8155
Abbe Number (Vd) 44.4
Dispersion Formula Schott
Wavelength Range 0.36 — 1.55 µm
$$n(\lambda) = \sqrt{3.21281 - 0.0155875\,\lambda^2 + 0.0282493\,\lambda^{-2} + 0.000864396\,\lambda^{-4} - 2.91755 \times 10^{-5}\,\lambda^{-6} + 2.99125 \times 10^{-6}\,\lambda^{-8}}$$
Thermal Properties
TCE -30/70°C (10-6/K) 5.6
TCE 100/300°C (10-6/K) 7.2
Thermal Conductivity (W/mK) —
Heat Capacity (J/gK) —
$$\frac{dn}{dT} = \frac{n_0^2 - 1}{2\,n_0}\left[3.02 \times 10^{-6} + 2(1.34 \times 10^{-8})\,\Delta T + 3(-1.66 \times 10^{-10})\,\Delta T^2 + \frac{6.41 \times 10^{-7} + 2(6.88 \times 10^{-10})\,\Delta T}{\lambda - 0.194}\right] \Delta T = T - T_0, \quad T_0 = 20\,°\text{C}$$
Physical Properties
Density (g/cm³) 4.8
Relative Cost —
Mechanical Properties
Young's Modulus (GPa) —
Poisson's Ratio —
Knoop Hardness (kgf/mm²) —
Chemical Resistance
Climatic Resistance 1
Stain Resistance —
Acid Resistance 2
Alkali Resistance —
Phosphate Resistance —
Similar Glasses (Other Manufacturers)
Glass Manufacturer nd Vd Compare
LAH54 Ohara 1.815543 44.361146
S-LAH54 Ohara 1.815543 44.361146
TAFD10 Hoya 1.815502 44.5379
M-TAFD51 Hoya 1.8208 42.71
MP-TAFD51-50 Hoya 1.8213 42.72
MC-TAFD51-50 Hoya 1.8213 42.72
NBFD14 Hoya 1.801699 44.321602
H-ZLAF1 CDGM 1.80166 44.263459
D-ZLAF61-25 CDGM 1.82131 42.674895
D-ZLAF61 CDGM 1.82241 42.714541
Similar Glasses (Sumita)
Glass Manufacturer nd Vd Compare
LASFN10 Sumita 1.8155 44.4
K-VC100 Sumita 1.804 43.6
K-LaSFn9 Sumita 1.816 46.7
LASFN9 Sumita 1.816 46.7
K-VC100(M) Sumita 1.79916 43.5
K-LaSFn6 Sumita 1.804 46.6
LASFN19 Sumita 1.795 45.2
LASFN6 Sumita 1.80235 46.7
K-LaSFn3 Sumita 1.7995 42.3
LASFN3 Sumita 1.7995 42.3
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