Snell's Law
Interactive simulation of light refraction, critical angles, and total internal reflection.
How It Works
Snell's Law describes how light bends when passing between two transparent media with different refractive indices. The simulation shows the incident ray, refracted ray, and reflected ray in real-time.
Total Internal Reflection (TIR): When light travels from a denser to a less dense medium (n₁ > n₂) at an angle greater than the critical angle, all light reflects back. No refracted ray is transmitted.
Drag the ray endpoint on the canvas to adjust the incident angle, or use the slider. Change the refractive indices to see how different materials bend light. The reflectance percentage shows how much light is reflected vs. transmitted.