Geometric Optics Lab

Optics Lab — Interactive Ray Tracing Sandbox

This geometric optics sandbox lets you place and configure optical elements — convex lens, concave lens, plane mirror, prism, and glass slab — on a white canvas and trace colored light rays through them in real time. A draggable light source emits up to 15 rays at adjustable wavelength (380–750 nm), angle, and spread. Focal length, refractive index, and rotation are adjustable per element. Rays are traced with up to 12 bounces, and the thin lens equation and Snell's law are shown as a reference panel.

What you can do in this simulation

• Place convex lens, concave lens, plane mirror, prism, and glass slab
• Adjust source wavelength (380–750 nm), ray count (1–15), and beam spread
• Set focal length (30–200 px) per lens and refractive index (1–2.5) per element
• Drag and rotate any element to see ray paths update in real time
• Reference panel shows thin lens equation and Snell's law

Concepts covered

geometric optics · refraction · Snell's law · thin lens equation · total internal reflection · dispersion

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Related reading

• Thin Lenses, Ray Tracing, and Prisms: Free Online Optics Simulations
• Wave Optics in Your Browser: Interference, Diffraction, and Snell's Law

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