N-BAF51 by Schott

Preferred Unknown Environmentally Friendly

N-BAF51 by Schott is a preferred optical glass. It transmits from 0.35 to 2.50 µm with an nd of 1.65224 and a Vd of 44.96. It has medium thermal expansion (CTE of 8.37×10⁻⁶/K), average chemical resistance, and low relative cost.

Refractive Index vs Wavelength
Refractive Index Calculator
Valid range: 0.35–2.5 µm
dn/dλ vs Wavelength
dn/dλ Calculator
Valid range: 0.35–2.5 µm
Abbe Number Calculator
Transmission vs Wavelength
Transmission Calculator
Valid wavelength range: 0.350–2.500 µm
Optical Properties
Refractive Index (nd) 1.65224
Abbe Number (Vd) 44.96
Dispersion Formula Sellmeier
Wavelength Range 0.35 — 2.5 µm
$$n(\lambda) = \sqrt{1 + \frac{1.51504\,\lambda^2}{\lambda^2 - 0.00942735} + \frac{0.153622\,\lambda^2}{\lambda^2 - 0.0430827} + \frac{1.15428\,\lambda^2}{\lambda^2 - 124.89}}$$
Thermal Properties
TCE -30/70°C (10-6/K) 8.37
TCE 100/300°C (10-6/K) 9.49
Thermal Conductivity (W/mK) 0.67
Heat Capacity (J/gK) 0.84
$$\frac{dn}{dT} = \frac{n_0^2 - 1}{2\,n_0}\left[-2.84 \times 10^{-7} + 2(1.04 \times 10^{-8})\,\Delta T + 3(-1.8 \times 10^{-11})\,\Delta T^2 + \frac{7.01 \times 10^{-7} + 2(8.47 \times 10^{-10})\,\Delta T}{\lambda - 0.219}\right] \Delta T = T - T_0, \quad T_0 = 20\,°\text{C}$$
Physical Properties
Density (g/cm³) 3.333
Relative Cost 1.9
Mechanical Properties
Young's Modulus (GPa) 91.0
Poisson's Ratio 0.26
Knoop Hardness (kgf/mm²) 560.0
Chemical Resistance
Climatic Resistance 2
Stain Resistance 0
Acid Resistance 5
Alkali Resistance 1
Phosphate Resistance 1
Similar Glasses (Other Manufacturers)
Glass Manufacturer nd Vd Compare
BAF23 Hoya 1.652238 44.922169
ATF4 Hoya 1.653757 44.723072
C48-46 Corning 1.647747 46.227993
BAF12 Sumita 1.6393 45.0
BAM12 Ohara 1.6393 44.878032
S-BAM12 Ohara 1.6393 44.872804
BAF12 Hoya 1.639302 45.070071
BAF13 Hoya 1.668916 44.911265
BAH13 Ohara 1.668921 44.987354
BAF13 Sumita 1.66892 45.0
Similar Glasses (Schott)
Glass Manufacturer nd Vd Compare
BAF51 Schott 1.652242 44.930457
BAF13 Schott 1.668919 44.961828
BASF57 Schott 1.651474 41.901823
N-KZFS11 Schott 1.63775 42.41
BAFN10 Schott 1.670031 47.108735
N-BAF10 Schott 1.67003 47.11
BAF9 Schott 1.643276 47.958224
BASF6 Schott 1.667551 41.931404
BAFN11 Schott 1.666721 48.421391
BAF50 Schott 1.682726 44.503507
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