C78-56 by Corning

Standard Unknown Environmentally Friendly
Refractive Index vs Wavelength
Refractive Index Calculator
Valid range: 0.28–1.8 µm
dn/dλ vs Wavelength
dn/dλ Calculator
Valid range: 0.28–1.8 µm
Abbe Number Calculator
Transmission vs Wavelength
Transmission Calculator
Valid wavelength range: 0.280–1.800 µm
Optical Properties
Refractive Index (nd) 1.678004
Abbe Number (Vd) 55.519168
Dispersion Formula Schott
Wavelength Range 0.28 — 1.8 µm
$$n(\lambda) = \sqrt{2.76382 - 0.0119201\,\lambda^2 + 0.0187895\,\lambda^{-2} + 0.000122244\,\lambda^{-4} + 2.51563 \times 10^{-5}\,\lambda^{-6} - 9.48327 \times 10^{-7}\,\lambda^{-8}}$$
Thermal Properties
TCE -30/70°C (10-6/K) 6.7
TCE 100/300°C (10-6/K) 8.1
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) 3.59
Relative Cost
Mechanical Properties
Young's Modulus (GPa)
Poisson's Ratio
Knoop Hardness (kgf/mm²)
Chemical Resistance
Climatic Resistance
Stain Resistance
Acid Resistance
Alkali Resistance
Phosphate Resistance
Similar Glasses (Other Manufacturers)
Glass Manufacturer nd Vd
LAC12 Hoya 1.6779 55.52
H-LAK5A CDGM 1.6779 55.51497
LAK12 Sumita 1.6779 55.5
K-LaK12 Sumita 1.6779 55.5
S-LAL12Q Ohara 1.6779 55.346888
S-LAL12 Ohara 1.6779 55.341195
LAL12 Ohara 1.6779 55.337587
N-LAK12 Schott 1.6779 55.2
LAKN12 Schott 1.6779 55.199566
LAKL12 Schott 1.6779 54.92
Similar Glasses (Corning)
Glass Manufacturer nd Vd
C90-55 Corning 1.691008 54.793839
C97-55 Corning 1.697005 55.409848
C97-56 Corning 1.697 56.222926
C57-57 Corning 1.657503 57.198059
C51-56 Corning 1.651124 55.895803
C52-58 Corning 1.6516 58.511488
D13-54 Corning 1.713 53.843096
C58-51 Corning 1.658503 51.012014
C39-56 Corning 1.638505 55.504447
C42-58 Corning 1.642502 58.061633
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