C3 by Hoya

Obsolete Unknown Environmentally Dangerous
Refractive Index vs Wavelength
Refractive Index Calculator
Valid range: 0.25–1.55 µm
dn/dλ vs Wavelength
dn/dλ Calculator
Valid range: 0.25–1.55 µm
Abbe Number Calculator
Transmission vs Wavelength
Transmission Calculator
Valid wavelength range: 0.300–0.700 µm
Optical Properties
Refractive Index (nd) 1.518234
Abbe Number (Vd) 58.96082
Dispersion Formula Schott
Wavelength Range 0.25 — 1.55 µm
$$n(\lambda) = \sqrt{2.27432 - 0.00956343\,\lambda^2 + 0.0103635\,\lambda^{-2} + 0.000603516\,\lambda^{-4} - 5.14678 \times 10^{-5}\,\lambda^{-6} + 2.65072 \times 10^{-6}\,\lambda^{-8}}$$
Thermal Properties
TCE -30/70°C (10-6/K) 9.2
TCE 100/300°C (10-6/K)
Thermal Conductivity (W/mK)
Heat Capacity (J/gK)
$$\frac{dn}{dT} = \frac{n_0^2 - 1}{2\,n_0}\left[-1.39118 \times 10^{-6} + 2(0)\,\Delta T + 3(0)\,\Delta T^2 + \frac{0 + 2(0)\,\Delta T}{\lambda - 0}\right] \Delta T = T - T_0, \quad T_0 = 20\,°\text{C}$$
Physical Properties
Density (g/cm³) 2.54
Relative Cost
Mechanical Properties
Young's Modulus (GPa)
Poisson's Ratio
Knoop Hardness (kgf/mm²)
Chemical Resistance
Climatic Resistance 3
Stain Resistance 1
Acid Resistance 1
Alkali Resistance
Phosphate Resistance
Similar Glasses (Other Manufacturers)
Glass Manufacturer nd Vd
NSL3 Ohara 1.518229 58.966406
H-K10 CDGM 1.51818 58.949331
K3 Schott 1.51823 58.976559
K3 Sumita 1.51823 59.0
S-NSL3 Ohara 1.518229 58.902057
H-K51 CDGM 1.52307 58.639792
B270 Schott 1.52308 58.571369
N-K5 Schott 1.52249 59.48
H-K50 CDGM 1.52249 59.480754
K5 Schott 1.522489 59.482671
Similar Glasses (Hoya)
Glass Manufacturer nd Vd
E-C3 Hoya 1.51823 58.96
C12 Hoya 1.523073 58.640203
C5 Hoya 1.522488 59.447258
BACL3 Hoya 1.518351 60.396486
C40 Hoya 1.523 60.4016
BACL1 Hoya 1.526417 60.113677
C7 Hoya 1.511122 60.485929
C2 Hoya 1.51602 56.771193
ZNC1 Hoya 1.533149 58.063515
ZNC7 Hoya 1.508471 61.266087
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