BAF20 by Hoya

Obsolete Unknown Environmentally Dangerous
Refractive Index vs Wavelength
Refractive Index Calculator
Valid range: 0.334–2.325 µm
dn/dλ vs Wavelength
dn/dλ Calculator
Valid range: 0.334–2.325 µm
Abbe Number Calculator
Transmission vs Wavelength

No transmission data available.

Optical Properties
Refractive Index (nd) 1.685777
Abbe Number (Vd) 43.901833
Dispersion Formula Schott
Wavelength Range 0.334 — 2.325 µm
$$n(\lambda) = \sqrt{2.77357 - 0.00914798\,\lambda^2 + 0.023259\,\lambda^{-2} + 0.0004647\,\lambda^{-4} - 2.81081 \times 10^{-6}\,\lambda^{-6} + 3.20119 \times 10^{-6}\,\lambda^{-8}}$$
Thermal Properties
TCE -30/70°C (10-6/K)
TCE 100/300°C (10-6/K)
Thermal Conductivity (W/mK)
Heat Capacity (J/gK)
$$\frac{dn}{dT} = \frac{n_0^2 - 1}{2\,n_0}\left[0 + 2(0)\,\Delta T + 3(0)\,\Delta T^2 + \frac{0 + 2(0)\,\Delta T}{\lambda - 0}\right] \Delta T = T - T_0, \quad T_0 = 25\,°\text{C}$$
Physical Properties
Density (g/cm³)
Relative Cost
Mechanical Properties
Young's Modulus (GPa)
Poisson's Ratio
Knoop Hardness (kgf/mm²)
Chemical Resistance
Climatic Resistance
Stain Resistance
Acid Resistance
Alkali Resistance
Phosphate Resistance
Similar Glasses (Other Manufacturers)
Glass Manufacturer nd Vd
BAF50 Schott 1.682726 44.503507
BAFN1 Sumita 1.6825 44.5
K-BaFn1 Sumita 1.6825 44.5
ZBAF51 CDGM 1.682726 44.528543
IRG11 Generic IR 1.680932 44.434326
S-BAH54 Ohara 1.695 42.167111
BAH54 Ohara 1.695 42.167111
BAF13 Schott 1.668919 44.961828
BAH13 Ohara 1.668921 44.987354
BAF13 Sumita 1.66892 45.0
Similar Glasses (Hoya)
Glass Manufacturer nd Vd
BAF22 Hoya 1.682496 44.671672
ADF8 Hoya 1.686498 42.863902
BAF13 Hoya 1.668916 44.911265
BAFD6 Hoya 1.66755 41.933458
BAFD7 Hoya 1.70154 41.15
LAFL4 Hoya 1.712704 43.295113
BAF10 Hoya 1.67003 47.2
BAFD15 Hoya 1.701999 40.195943
LAFL20 Hoya 1.68248 48.197606
LAFL3 Hoya 1.700301 47.836538
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