TAFD31 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) 1.922501
Abbe Number (Vd) 35.946005
Dispersion Formula Schott
Wavelength Range 0.334 — 2.325 µm
$$n(\lambda) = \sqrt{3.5689 - 0.0131231\,\lambda^2 + 0.0416524\,\lambda^{-2} + 0.00135161\,\lambda^{-4} - 3.68628 \times 10^{-5}\,\lambda^{-6} + 7.7959 \times 10^{-6}\,\lambda^{-8}}$$
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
CAWO4 Generic Birefringent 1.920414 34.953592
H-ZLAF4LB CDGM 1.91082 35.282389
K-LaSFn23 Sumita 1.911 35.2
H-ZLAF4LA CDGM 1.91082 35.25034
S-LAH93 Ohara 1.90525 35.036826
H-ZLAF78B CDGM 1.90069 37.050531
CAWO4-E Generic Birefringent 1.937211 33.304949
LASF18A Schott 1.913482 32.364492
LASFN22 Sumita 1.898 34.0
K-LaSFn22 Sumita 1.898 34.0
Similar Glasses (Hoya)
Glass Manufacturer nd Vd
TAFD35 Hoya 1.91082 35.25
TAFD35L Hoya 1.91082 35.25
TAFD37A Hoya 1.90043 37.37
TAFD37 Hoya 1.90043 37.37
TAFD25L Hoya 1.90366 31.32
TAFD25 Hoya 1.90366 31.32
TAFD45L Hoya 1.95375 32.32
TAFD45 Hoya 1.95375 32.32
MC-TAFD307 Hoya 1.88202 37.22
MP-TAFD307 Hoya 1.88202 37.22
Compare Glasses