FD2 by Hoya

Obsolete Unknown Environmentally Dangerous
Refractive Index vs Wavelength
Refractive Index Calculator
Valid range: 0.25–1.55 µm
dn/dλ vs Wavelength
dn/dλ Calculator
Valid range: 0.25–1.55 µm
Abbe Number Calculator
Transmission vs Wavelength
Transmission Calculator
Valid wavelength range: 0.330–1.550 µm
Optical Properties
Refractive Index (nd) 1.647693
Abbe Number (Vd) 33.836872
Dispersion Formula Schott
Wavelength Range 0.25 — 1.55 µm
$$n(\lambda) = \sqrt{2.63562 - 0.00883964\,\lambda^2 + 0.0256448\,\lambda^{-2} + 0.000965224\,\lambda^{-4} - 1.83048 \times 10^{-5}\,\lambda^{-6} + 5.55635 \times 10^{-6}\,\lambda^{-8}}$$
Thermal Properties
TCE -30/70°C (10-6/K) 8.6
TCE 100/300°C (10-6/K) 96.0
Thermal Conductivity (W/mK)
Heat Capacity (J/gK)
$$\frac{dn}{dT} = \frac{n_0^2 - 1}{2\,n_0}\left[4.39356 \times 10^{-6} + 2(0)\,\Delta T + 3(0)\,\Delta T^2 + \frac{0 + 2(0)\,\Delta T}{\lambda - 0}\right] \Delta T = T - T_0, \quad T_0 = 20\,°\text{C}$$
Physical Properties
Density (g/cm³) 3.85
Relative Cost
Mechanical Properties
Young's Modulus (GPa)
Poisson's Ratio
Knoop Hardness (kgf/mm²)
Chemical Resistance
Climatic Resistance 1
Stain Resistance 1
Acid Resistance 2
Alkali Resistance
Phosphate Resistance
Similar Glasses (Other Manufacturers)
Glass Manufacturer nd Vd
ZF1 CDGM 1.647693 33.836872
H-ZF1 CDGM 1.64769 33.840317
SF2 Schott 1.64769 33.85
N-SF2 Schott 1.64769 33.82
PBM22 Ohara 1.647689 33.802937
S-TIM22 Ohara 1.647689 33.792803
H-ZF1A CDGM 1.64769 33.887993
SF2 Sumita 1.64769 33.9
SF12 Schott 1.64831 33.841187
SF12 Sumita 1.64831 33.8
Similar Glasses (Hoya)
Glass Manufacturer nd Vd
E-FD2 Hoya 1.64769 33.84
FD12 Hoya 1.648308 33.793909
FD9 Hoya 1.654462 33.717017
FD7 Hoya 1.639803 34.568909
E-FD7 Hoya 1.6398 34.57
F6 Hoya 1.636356 35.340304
FD19 Hoya 1.666797 33.059707
BAFD2 Hoya 1.664457 35.887705
F7 Hoya 1.625363 35.583498
E-F1 Hoya 1.62588 35.74
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