FD18 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) 1.721507
Abbe Number (Vd) 29.243436
Dispersion Formula Schott
Wavelength Range 0.334 — 2.325 µm
$$n(\lambda) = \sqrt{2.85938 - 0.0104521\,\lambda^2 + 0.0320782\,\lambda^{-2} + 0.00196454\,\lambda^{-4} - 0.00010417\,\lambda^{-6} + 1.34407 \times 10^{-5}\,\lambda^{-8}}$$
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
PBH18 Ohara 1.721506 29.243262
SF18 Schott 1.72151 29.245495
S-TIH18 Ohara 1.721507 29.23233
SF18 Sumita 1.72151 29.3
P-SF69 Schott 1.7225 29.23
CD120 Sumita 1.7225 29.2
K-CD120 Sumita 1.7225 29.2
SFN1 Sumita 1.72022 29.3
D17-29 Corning 1.717409 29.492751
H-ZF3 CDGM 1.71736 29.49911
Similar Glasses (Hoya)
Glass Manufacturer nd Vd
FD20 Hoya 1.720225 29.300359
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
FD13 Hoya 1.740774 27.764991
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