luma. A playground for light
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LIGHT STUDIES

Prism study / 01

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Explore a scene
LUMA / FIELD NOTES

A little light
goes a long way.

This is a small, hands-on playground for geometric optics. Set something in the path of a beam and see what happens.

01 / Find your light
Add a source and choose white light or a single color. A wider beam makes a lens’s focus easier to see.
02 / Change its path
Mirrors reflect. Prisms refract, separating wavelengths. Lenses bring parallel rays to a focus. Drag any object, or select it in the Objects menu.
03 / Make it yours
Adjust the controls, duplicate objects, or start from a new scene. Your work is saved automatically in this browser. Save image exports the light as a PNG.
A note on the physics

Prisms follow Snell’s law, including total internal reflection, with an illustrative Cauchy dispersion model. Lenses use the ideal thin-lens approximation. Colors and glow are artistic; diffraction, partial reflections, and interference are not simulated. Overlapping prisms are treated as one material at each point.

Explore the science at OpenStax ↗
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