SFLD20 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: 0.370–2.000 µm
Optical Properties
Refractive Index (nd) 1.81786
Abbe Number (Vd) 23.7
Dispersion Formula Schott
Wavelength Range 0.27 — 2.0 µm
$$n(\lambda) = \sqrt{3.15749 - 0.0151203\,\lambda^2 + 0.0425736\,\lambda^{-2} + 0.00406568\,\lambda^{-4} - 0.000321559\,\lambda^{-6} + 3.89423 \times 10^{-5}\,\lambda^{-8}}$$
Thermal Properties
TCE -30/70°C (10-6/K)
TCE 100/300°C (10-6/K) 10.6
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) 3.43
Relative Cost
Mechanical Properties
Young's Modulus (GPa)
Poisson's Ratio
Knoop Hardness (kgf/mm²)
Chemical Resistance
Climatic Resistance 1
Stain Resistance
Acid Resistance 1
Alkali Resistance
Phosphate Resistance
Similar Glasses (Other Manufacturers)
Glass Manufacturer nd Vd
M-FDS910 Hoya 1.82115 24.06
MC-FDS910-50 Hoya 1.82165 24.04
MP-FDS910-50 Hoya 1.82165 24.04
S-NPH1W Ohara 1.808095 22.760817
S-NPH1 Ohara 1.808095 22.760817
FD225 Hoya 1.80809 22.76
H-ZF71 CDGM 1.8081 22.698087
H-ZF71GT CDGM 1.8081 22.698087
SF6G05 Schott 1.80906 25.27
ZF7 CDGM 1.806277 25.380144
Similar Glasses (Sumita)
Glass Manufacturer nd Vd
SFLD60 Sumita 1.80645 24.4
K-CD180 Sumita 1.80645 24.4
K-PSFn3(M) Sumita 1.83352 24.0
SFLD6 Sumita 1.80518 25.4
K-SFLD6 Sumita 1.80518 25.4
SF6 Sumita 1.80518 25.5
SF6W Sumita 1.80518 25.5
SFLD66 Sumita 1.79925 24.6
K-SFLD66 Sumita 1.79925 24.6
K-CD180(M) Sumita 1.79912 24.7
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