Huygens' Refraction Proof

The simulation visualises Huygens' principle in action, showing how secondary wavelets combine to form new wavefronts when light passes from one medium to another. By constructing the refracted wavefront step‑by‑step, students see how Snell’s law emerges from the geometry of the wavelets and can also observe the conditions that lead to total internal reflection.

Interactive controls let learners advance through numbered steps, play or step the construction, and select the pair of media (water, glass, diamond) as well as the direction of propagation (air‑to‑glass or glass‑to‑air). Additional toggles switch on the train of wavefronts and the real‑time light‑field rendering that displays Fresnel amplitudes across the interface.

Through this visual approach students connect the wave‑front description of light with ray optics, derive the relationship between incident and refracted angles, and understand why light is totally reflected beyond the critical angle, reinforcing concepts in wave optics and geometric optics.