In some cases, solving nonlinear equations analytically is extremly difficult. SciPy provides a fsolve function which uses the iterative method to solve the equations numerically.
When light transmits a material and the angle of incidence is non-zero, the S-polarized and P-polarized lights propagate along different routes. This is called birefringence:
The absorption coefficient of the material can be calculated by subtracting reflectance and transmittance from 100:
Alternatively, the absorption coefficient of the material can be calculated from transmittance and refractive index:
Based on the above equations, we can calculate refractive index from reflectance and transmittance:
