Description
A diffraction grating — an optical element with thousands of parallel grooves per millimetre — disperses incident light by wavelength through constructive interference at angles determined by the groove spacing and the incident light’s wavelength. This image was made using a holographic transmission grating with 1,000 lines per millimetre, a single white LED point source at the optimal incidence angle, and a black velvet background. The resulting diffraction pattern fans out across the frame: from deep violet at the lowest diffraction angle through blue, cyan, green, yellow, orange, to deep red at the maximum angle, with a bright white undispersed central maximum. Shot at f/8 to keep the full fan in focus across its angular spread, the image records the full visible spectrum in its correct spectral sequence — a pure scientific demonstration rendered as a visually compelling composition.
