What a prism changes
In Prism Riddle, light changes direction when it enters and leaves a glass prism. Different wavelengths bend by different amounts, so a white beam can spread into a spectrum. The orientation of the glass changes which surfaces the light meets and the angle at which it leaves. A small rotation can therefore move the entire spectrum across the chamber.
This makes a prism puzzle different from a simple mirror maze. A mirror turns a beam while preserving its wavelengths. A prism can send those wavelengths along slightly different paths. You need to consider where the spectrum will arrive, which part can pass an opening and which colors a gate will accept.
Why moving a prism matters as much as rotating it
Two prisms at the same angle can produce very different results if one sits higher or farther from the next instrument. Changing its position changes where the incoming beam meets the glass and how far the separated rays can travel. A spectrum that is compact near the prism can be much wider when it reaches a distant mirror.
Start by placing the prism across the beam. Watch the outgoing light while you rotate slowly. Once it points toward the correct part of the chamber, adjust its position to make the next mirror or opening useful. The light is always calculated from the current arrangement, so you can test each idea immediately.
Combine a prism with a mirror or lens
A mirror can catch a slanted spectrum and carry it through another part of the ruins. Its angle needs to match that slanted input; a familiar angle from an earlier white-light puzzle may not work here. A lens can change the width of the rays after the turn, helping the useful wavelengths reach a small gate lens.
The third free chamber, The Hidden Spectrum, combines a lower mirror route, a prism, an upper mirror, a lens and a filter. It introduces dispersion as part of a complete route, rather than as an isolated color effect.
A filter removes colors; it does not invent them
White light contains several wavelength bands. A green filter passes the green part and absorbs most of the rest. It cannot turn a purely red input into a green beam. That distinction matters when a gate requires both a clean color and enough energy: filtering a badly positioned spectrum may leave almost nothing to collect.
Read the color-purity indicator together with the energy indicator. A clean but weak beam and a bright but mixed beam can both fail the same gate for different reasons. The appropriate fix depends on which condition is missing.
What the game simulates
The game uses finite-width geometric light sampled across 27 wavelengths. It includes wavelength-dependent refraction, reflection, splitting and filtering, with a thin-lens approximation for lenses. Glow and texture make the light visible; they do not create additional energy. Interference, diffraction and polarization are outside the current model.
For background on the underlying phenomenon, see the OpenStax introduction to refraction. To explore it directly, start the free prism chamber or open the workshop.