NBFD27 by Hoya

Preferred Very Common Environmentally Dangerous
Refractive Index vs Wavelength
Refractive Index Calculator
Valid range: 0.36501–1.5296 µm
dn/dλ vs Wavelength
dn/dλ Calculator
Valid range: 0.36501–1.5296 µm
Abbe Number Calculator
Transmission vs Wavelength
Transmission Calculator
Valid wavelength range: 0.360–2.500 µm
Optical Properties
Refractive Index (nd) 1.9011
Abbe Number (Vd) 27.06
Dispersion Formula Schott
Wavelength Range 0.36501 — 1.5296 µm
$$n(\lambda) = \sqrt{3.46133 - 0.0158781\,\lambda^2 + 0.0461568\,\lambda^{-2} + 0.00339272\,\lambda^{-4} - 0.000247499\,\lambda^{-6} + 3.1074 \times 10^{-5}\,\lambda^{-8}}$$
Thermal Properties
TCE -30/70°C (10-6/K) 7.1
TCE 100/300°C (10-6/K) 8.6
Thermal Conductivity (W/mK)
Heat Capacity (J/gK)
$$\frac{dn}{dT} = \frac{n_0^2 - 1}{2\,n_0}\left[2.63 \times 10^{-7} + 2(9.13 \times 10^{-9})\,\Delta T + 3(-2.88 \times 10^{-11})\,\Delta T^2 + \frac{1.09 \times 10^{-6} + 2(1.4 \times 10^{-9})\,\Delta T}{\lambda - 0.26}\right] \Delta T = T - T_0, \quad T_0 = 23\,°\text{C}$$
Physical Properties
Density (g/cm³) 3.83
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 1
Alkali Resistance
Phosphate Resistance
Notes

Recommended glass type

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Glass Manufacturer nd Vd
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