AOTF (Acousto-Optic Tunable Filter)

An Acousto-Optic Tunable Filter (AOTF) is a device that uses sound waves in a crystal to selectively control which wavelengths (colors) of light pass through. When an electrical signal generates ultrasonic waves inside the crystal, it creates a dynamic diffraction grating that can filter specific wavelengths from a broad light source. By adjusting the frequency of the sound waves, the AOTF can rapidly select different wavelengths without moving parts. This makes it useful in applications like spectroscopy, remote sensing, and imaging, allowing precise, fast, and tunable control over the light spectrum.