Optical constants of SUMITA - LaK (Lanthanum crown)
K-LaK18
Wavelength:
µm
(0.290–2.000)
Complex refractive index (n+ik)
n
k
LogX
LogY
eV
Derived optical constants
Dispersion formula
$$n^2=2.9333796-0.014920134λ^{2}+0.020207432λ^{-2}+0.00041238589λ^{-4}-1.230332\text{×}10^{-05}λ^{-6}+1.1436994\text{×}10^{-06}λ^{-8}$$Conditions & Spec sheet
n_is_absolute: false
wavelength_is_vacuum: false
temperature: 20.0 °C
thermal_dispersion:
- type: "Schott formula"
coefficients: 6.73e-07 2.1e-08 -1.63e-10 4.91e-07 2.14e-10 0.164
nd: 1.72916
Vd: 54.7
glass_code: 729547
density: 4.08 g/cm3
thermal_expansion:
- temperature_range: -30 70 °C
coefficient: 5.6e-06 K-1
- temperature_range: 20 300 °C
coefficient: 7.1e-06 K-1
dPgF: -0.0092
climatic_resistance: 1.0
acid_resistance: 4.0
References
SUMITA Zemax catalog 2017-02-02 (obtained from http://www.sumita-opt.co.jp)
See also SUMITA optical glass data book