TAC4 by Hoya

Special Very Rare 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: 0.280–1.550 µm
Optical Properties
Refractive Index (nd) 1.734
Abbe Number (Vd) 51.05
Dispersion Formula Schott
Wavelength Range 0.36501 — 1.5296 µm
$$n(\lambda) = \sqrt{2.94256 - 0.0132666\,\lambda^2 + 0.0235592\,\lambda^{-2} - 0.00016399\,\lambda^{-4} + 9.23708 \times 10^{-5}\,\lambda^{-6} - 4.8616 \times 10^{-6}\,\lambda^{-8}}$$
Thermal Properties
TCE -30/70°C (10-6/K) 5.2
TCE 100/300°C (10-6/K) 6.6
Thermal Conductivity (W/mK)
Heat Capacity (J/gK)
$$\frac{dn}{dT} = \frac{n_0^2 - 1}{2\,n_0}\left[9.29549 \times 10^{-6} + 2(0)\,\Delta T + 3(0)\,\Delta T^2 + \frac{0 + 2(0)\,\Delta T}{\lambda - 0}\right] \Delta T = T - T_0, \quad T_0 = 23\,°\text{C}$$
Physical Properties
Density (g/cm³) 4.06
Relative Cost
Mechanical Properties
Young's Modulus (GPa)
Poisson's Ratio
Knoop Hardness (kgf/mm²)
Chemical Resistance
Climatic Resistance 1
Stain Resistance 3
Acid Resistance 4
Alkali Resistance
Phosphate Resistance
Notes

Not in a position to accept new order because of discontinuation.

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Glass Manufacturer nd Vd
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