FD20 by Hoya

Obsolete Unknown Environmentally Dangerous

FD20 by Hoya is an obsolete optical glass. It transmits from 0.33 to 2.33 µm with an nd of 1.720225 and a Vd of 29.300359. It has dangerous environmental properties.

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.

Transmission Calculator
Valid wavelength range: 0.334–2.325 µm
Optical Properties
Refractive Index (nd) 1.720225
Abbe Number (Vd) 29.300359
Dispersion Formula Schott
Wavelength Range 0.334 — 2.325 µm
$$n(\lambda) = \sqrt{2.84804 - 0.00701304\,\lambda^2 + 0.0372191\,\lambda^{-2} + 0.000297448\,\lambda^{-4} + 0.000127677\,\lambda^{-6} + 2.01434 \times 10^{-6}\,\lambda^{-8}}$$
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 Compare
SFN1 Sumita 1.72022 29.3
SF18 Sumita 1.72151 29.3
SF18 Schott 1.72151 29.245495
PBH18 Ohara 1.721506 29.243262
S-TIH18 Ohara 1.721507 29.23233
P-SF69 Schott 1.7225 29.23
K-CD120 Sumita 1.7225 29.2
CD120 Sumita 1.7225 29.2
D17-29 Corning 1.717409 29.492751
H-ZF3 CDGM 1.71736 29.49911
Similar Glasses (Hoya)
Glass Manufacturer nd Vd Compare
FD18 Hoya 1.721507 29.243436
E-FD1 Hoya 1.71736 29.5
E-FD1L Hoya 1.71736 29.5
FD1 Hoya 1.71736 29.50028
FDS2 Hoya 1.7283 28.674457
E-FD10 Hoya 1.72825 28.32
E-FD10L Hoya 1.72825 28.32
FD10 Hoya 1.728252 28.319563
FD3 Hoya 1.739999 28.245048
E-FD15 Hoya 1.69895 30.05
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