An Acousto-Optic Modulator (AOM) is a device that uses sound waves to control light. It works by applying an RF (radio frequency) signal to a piezoelectric transducer, which generates ultrasonic waves in a crystal (e.g., tellurium dioxide). These waves create a periodic refractive index variation, acting like a moving diffraction grating. When laser light passes through, it gets diffracted and shifted in frequency.
Key Features:
Fast modulation (up to MHz/GHz speeds)
Precise control of light intensity, frequency, and direction
Low power consumption
Applications:
Laser beam steering & switching
Optical communication
Spectroscopy & laser cooling
AOMs are essential in photonics for their speed and efficiency in manipulating light.