White Light Spectrum - Physics Demonstrations - White Light Spectrum | Physics Undergraduate Labs

Overhead projectors generate significant heat during operation. Avoid touching the projector deck or lens assembly during or immediately after use. If the projector will be on for extended periods, ensure adequate ventilation to prevent overheating.

Purpose

Demonstrates that white light is composed of all visible wavelengths by dispersing it into a continuous spectrum with a diffraction grating. Provides a foundation for spectroscopy and the electromagnetic spectrum.

$Overhead projector with diffraction grating on lens, projecting a bright white central slit image flanked by symmetric rainbow spectra (red on outside, blue/violet on inside) onto the wall$

Figure 1: Overhead projector with diffraction grating dispersing white light into first-order spectra on both sides of the central beam. Red is diffracted to larger angles (outside), violet to smaller angles (inside).

Medium Diffraction Grating

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Safety Warnings

Warning: Overhead Projector Heat

Purpose