Fabry-Pérot cavity

A Fabry-Pérot cavity is an optical device that consists of two parallel mirrors facing each other, creating a space where light can bounce back and forth multiple times. When light of certain wavelengths enters, it undergoes constructive interference, meaning the waves reinforce each other, resulting in strong transmission at specific colors. This setup enhances or filters particular wavelengths, making it useful in lasers, spectroscopy, and optical sensors. The precise control of light within this cavity allows scientists and engineers to analyze or generate highly specific light signals with great accuracy.