CSK12 by Sumita

Obsolete Very Rare Environmentally Dangerous
Refractive Index vs Wavelength
Refractive Index Calculator
Valid range: 0.27–2.0 µm
dn/dλ vs Wavelength
dn/dλ Calculator
Valid range: 0.27–2.0 µm
Abbe Number Calculator
Transmission vs Wavelength
Transmission Calculator
Valid wavelength range: 0.310–2.000 µm
Optical Properties
Refractive Index (nd) 1.5865
Abbe Number (Vd) 59.6
Dispersion Formula Schott
Wavelength Range 0.27 — 2.0 µm
$$n(\lambda) = \sqrt{2.48004 - 0.0111435\,\lambda^2 + 0.0128403\,\lambda^{-2} + 0.000533432\,\lambda^{-4} - 4.40874 \times 10^{-5}\,\lambda^{-6} + 2.41415 \times 10^{-6}\,\lambda^{-8}}$$
Thermal Properties
TCE -30/70°C (10-6/K)
TCE 100/300°C (10-6/K) 9.5
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) 3.0
Relative Cost
Mechanical Properties
Young's Modulus (GPa)
Poisson's Ratio
Knoop Hardness (kgf/mm²)
Chemical Resistance
Climatic Resistance 2
Stain Resistance
Acid Resistance 4
Alkali Resistance
Phosphate Resistance
Similar Glasses (Other Manufacturers)
Glass Manufacturer nd Vd
P-SK57 Schott 1.587 59.6
D-ZK2L CDGM 1.587 59.600321
D-ZK2L-25 CDGM 1.58625 59.524868
P-SK57Q1 Schott 1.586 59.5
L-BAL43 Ohara 1.585729 59.69698
L-BAL42P Ohara 1.58593 59.248294
D-ZK2A CDGM 1.58313 59.539751
H-ZK2 CDGM 1.58313 59.460082
MP-BACD12 Hoya 1.58313 59.46
M-BACD12 Hoya 1.58313 59.46
Similar Glasses (Sumita)
Glass Manufacturer nd Vd
CSK120 Sumita 1.587 59.6
K-CSK120 Sumita 1.587 59.6
K-SKLD120 Sumita 1.5868 59.8
K-SKLD120(M) Sumita 1.58401 59.5
K-CSK120(M) Sumita 1.58445 59.2
SK12 Sumita 1.58313 59.3
K-SKLD200 Sumita 1.5866 59.0
K-SKLD100(M) Sumita 1.58773 60.4
K-SKLD200(M) Sumita 1.58355 58.8
K-PSK100(M) Sumita 1.58792 60.6
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