Visualizing the beauty in physics and mathematics
A plane wave with wavelength $\lambda$ strikes a thin film an angle $\theta_i$ with the normal. The film has refractive index $n$ and thickness $a$. The phase difference between the rays reflected from the first and second surfaces is:
\[\begin{equation}\delta= \frac{4\pi\cdot a\cdot n\cdot \cos(\theta_i)}{\lambda} +\pi\end{equation}\]There is additional interference from rays reflected inside the film at the first surface:
\[\begin{equation}\delta = \frac{4\pi\cdot a\cdot n\cdot \cos(\theta_i)}{\lambda}\end{equation}\]The program shows a color plot of the intensity of a given wavelength.
• Based on Thin film interference by reflection (AJP 72,1248-1253)
• From Computational Problems for Physics by RH Landau, MJ Paez, and CC Bordeianu.
• Refactored by Zeger Hendrikse in thin_film.py
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