Classics revisited: A diffraction grating

Описание: This is a remake, in much higher resolution and with a different color gradient, of the simulation    • Diffraction of a wave on a grating   of a diffraction grating.
Diffraction gratings are optical devices that can have weird effects on light, such as splitting it into several beams traveling in different directions. This simulation illustrates such an effect for waves encountering a grating made of evenly spaced circular obstacles.
The video has two parts, showing the same simulation with two different color schemes:
Wave height: 0:00
Average energy (log scale): 1:37
In the first part, the color hue shows the wave height. In the second part, it shows the energy, averaged from the beginning of the simulation, on a logarithmic scale. There are absorbing boundary conditions on the outer boundaries of the simulation.

Render time: 25 minutes 56 seconds
Color scheme: Part 1 - Twilight by Bastian Bechtold
https://github.com/bastibe/twilight
Part 2 - Inferno by Nathaniel J. Smith and Stefan van der Walt
https://github.com/BIDS/colormap

Music: "Eureka" by Huma-Huma

See also https://images.math.cnrs.fr/Des-ondes... for more explanations (in French) on a few previous simulations of wave equations.

The simulation solves the wave equation by discretization. The algorithm is adapted from the paper https://hplgit.github.io/fdm-book/doc...
C code: https://github.com/nilsberglund-orlea...
https://www.idpoisson.fr/berglund/sof...
Many thanks to Marco Mancini and Julian Kauth for helping me to accelerate my code!

#wave_equation #waves #diffraction #diffraction_grating