Toolgeist › Math & Unit

Geometric Ray Optics Sandbox — Real Snell's Law Refraction

Place laser sources, convex glass lenses, dispersing prisms and flat mirrors on a canvas and watch light rays trace through the scene using actual Snell's law refraction computed in real time — not pre-set beam paths — so moving a lens or changing its curvature genuinely changes where the light goes, the same way it would on an optical bench.

How to use Geometric Ray Optics Sandbox

  1. Place a laser source, then add lenses, prisms and mirrors.
  2. Watch rays trace and refract through the scene live.
  3. Move and rotate elements to see the ray paths update.
  4. Try a preset — focusing lens, prism dispersion, mirror reflection.

Frequently asked questions

Is the refraction physically accurate?
Yes — ray paths are computed using Snell's law at each surface based on the refractive indices you set, not a scripted or pre-baked visual effect.
Why does a prism split light into colours here?
Refractive index varies slightly with wavelength (dispersion) — the simulation models this, so a prism genuinely spreads a beam into its component colours rather than just displaying a rainbow texture.
Can I simulate a real lens configuration?
Yes — set focal length, curvature and position to approximate a real lens setup and see where the focal point actually falls, useful for building intuition before working through the physics by hand.

Related Math & Unit tools

Also searched for: ray optics simulator online · snells law refraction simulator · interactive lens prism simulator

Browse all 738 free tools on Toolgeist →