Interference: How Light Waves Combine and Cancel

Interference occurs when two or more light waves overlap and interact.
When waves line up in step, they reinforce each other—this is constructive interference.
When waves are out of step, they cancel each other out—destructive interference.
Soap bubbles shimmer with colors because light waves reflect and interfere within their thin film.
Oil slicks on water create rainbow patterns through thin-film interference.
The double-slit experiment shows bright and dark bands formed by interference of light waves.
Interference proves light behaves like a wave, not just as particles.
Noise-canceling headphones use the same principle, but with sound waves.
Interference patterns help scientists measure tiny distances with extreme precision.
From holograms to fiber optics, interference makes futuristic technologies possible.