BPH40 by Ohara

Obsolete Unknown Environmentally Dangerous
Refractive Index vs Wavelength
Refractive Index Calculator
Valid range: 0.3–2.4 µm
dn/dλ vs Wavelength
dn/dλ Calculator
Valid range: 0.3–2.4 µm
Abbe Number Calculator
Transmission vs Wavelength
Transmission Calculator
Valid wavelength range: 0.330–0.700 µm
Optical Properties
Refractive Index (nd) 1.676498
Abbe Number (Vd) 37.537388
Dispersion Formula Schott
Wavelength Range 0.3 — 2.4 µm
$$n(\lambda) = \sqrt{2.73748 - 0.0131531\,\lambda^2 + 0.0238953\,\lambda^{-2} + 0.00110783\,\lambda^{-4} - 4.88192 \times 10^{-5}\,\lambda^{-6} + 5.4774 \times 10^{-6}\,\lambda^{-8}}$$
Thermal Properties
TCE -30/70°C (10-6/K) 5.3
TCE 100/300°C (10-6/K) 6.4
Thermal Conductivity (W/mK)
Heat Capacity (J/gK)
$$\frac{dn}{dT} = \frac{n_0^2 - 1}{2\,n_0}\left[1.01 \times 10^{-5} + 2(0)\,\Delta T + 3(0)\,\Delta T^2 + \frac{0 + 2(0)\,\Delta T}{\lambda - 0}\right] \Delta T = T - T_0, \quad T_0 = 25\,°\text{C}$$
Physical Properties
Density (g/cm³) 3.76
Relative Cost
Mechanical Properties
Young's Modulus (GPa)
Poisson's Ratio
Knoop Hardness (kgf/mm²)
Chemical Resistance
Climatic Resistance
Stain Resistance
Acid Resistance 52
Alkali Resistance
Phosphate Resistance 4
Similar Glasses (Other Manufacturers)
Glass Manufacturer nd Vd
ADF405 Hoya 1.6765 37.477902
KZFS7A Schott 1.68064 37.389991
BASF12 Sumita 1.66998 39.2
BASF12 Schott 1.669979 39.200523
N-BASF2 Schott 1.66446 36.0
BASF2 Sumita 1.66446 35.9
BAFD2 Hoya 1.664457 35.887705
BASF2 Schott 1.66446 35.829357
K-PG395 Sumita 1.658 36.9
H-ZBAF4 CDGM 1.66426 35.484251
Similar Glasses (Ohara)
Glass Manufacturer nd Vd
S-NBH52 Ohara 1.672999 38.14817
S-NBH52V Ohara 1.673 38.256077
S-BAH32 Ohara 1.669979 39.271035
BAH32 Ohara 1.669979 39.279752
BAH22 Ohara 1.664459 35.812757
S-NBH5 Ohara 1.654115 39.682794
BPH5 Ohara 1.654115 39.687638
BAH30 Ohara 1.650158 39.390461
BAH71 Ohara 1.701998 40.097173
BAH26 Ohara 1.667551 41.927521
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