FDS1 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: 0.380–1.550 µm
Optical Properties
Refractive Index (nd) 1.922859
Abbe Number (Vd) 20.883457
Dispersion Formula Schott
Wavelength Range 0.25 — 1.55 µm
$$n(\lambda) = \sqrt{3.49374 - 0.0117572\,\lambda^2 + 0.0583577\,\lambda^{-2} + 0.00530804\,\lambda^{-4} - 0.000399306\,\lambda^{-6} + 5.45179 \times 10^{-5}\,\lambda^{-8}}$$
Thermal Properties
TCE -30/70°C (10-6/K)
TCE 100/300°C (10-6/K)
Thermal Conductivity (W/mK)
Heat Capacity (J/gK)
$$\frac{dn}{dT} = \frac{n_0^2 - 1}{2\,n_0}\left[0 + 2(0)\,\Delta T + 3(0)\,\Delta T^2 + \frac{0 + 2(0)\,\Delta T}{\lambda - 0}\right] \Delta T = T - T_0, \quad T_0 = 20\,°\text{C}$$
Physical Properties
Density (g/cm³) 6.03
Relative Cost
Mechanical Properties
Young's Modulus (GPa)
Poisson's Ratio
Knoop Hardness (kgf/mm²)
Chemical Resistance
Climatic Resistance 1
Stain Resistance 0
Acid Resistance 4
Alkali Resistance
Phosphate Resistance
Similar Glasses (Other Manufacturers)
Glass Manufacturer nd Vd
PBH21 Ohara 1.922861 20.884172
N-SF66 Schott 1.92286 20.88
SF66 Schott 1.92286 20.88
H-ZF62GT CDGM 1.92286 20.879915
H-ZF62 CDGM 1.92286 20.879915
PBH71 Ohara 1.922864 21.288699
REALVIEW_1.9_LIGHTWEIGHT Schott 1.922002 21.44
SF58 Schott 1.917613 21.51112
PBH72 Ohara 1.915356 21.171926
K-PSFn5 Sumita 1.9211 22.4
Similar Glasses (Hoya)
Glass Manufacturer nd Vd
E-FDS1-W Hoya 1.92286 20.88
M-FDS1 Hoya 1.92286 20.88
MP-FDS1 Hoya 1.92286 20.88
E-FDS1 Hoya 1.92286 20.88
FDS24 Hoya 1.92119 23.96
FDS24-SW Hoya 1.92119 23.96
FDS24-W Hoya 1.92119 23.96
FDS18-W Hoya 1.94595 17.98
FDS18 Hoya 1.94595 17.98
NBFD265 Hoya 1.95203 26.2
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