Put on a pair of diffraction glasses and suddenly the world explodes into rainbows.

These lenses are etched with thousands of microscopic slits—so tiny and evenly spaced that they act like an engineered crystal lattice for light. When photons stream through, they’re forced to interfere with themselves, splitting a single beam into its component wavelengths.

What looks like a simple party trick is actually the same principle astronomers use to decode starlight: diffraction patterns, called spectral lines, reveal the chemical makeup of distant stars and galaxies. This information even hints to the light source’s temperature, velocity, size, and more.

Every light source—LEDs, neon signs, even a candle flame—becomes a shimmering spectrum, a fingerprint of energy. In a sense, diffraction glasses let you see the atomic language of the universe directly, transforming mundane nightlife into an experiment in quantum-scale optics.