Acousto-optic modulators are used to vary and control laser beam intensity. A Bragg configuration gives a single first order output beam, which intensity is directly linked to the power of the RF control signal. The rise time of the modulator is simply deduced from the necessary time for the acoustic wave to travel through the laser beam. For highest speeds the laser beam will be focused down, forming a beam waist as it passes through the modulator. the best performances(rise time, extinction ratio...). The RF driver features all the necessary signals to drive the modulator(carrier frequency, amplifier..). with analog or digital input controls. Main applications : Fast optical switches, printing and marking applications, laser power noise eater...

A Q-switch is a special modulator which introduces high repetition rate losses inside a laser cavity (typ : 1 to 100 kHz). They are designed for minimum insertion loss and to be able to withstand very high laser powers. In normal use an RF signal is applied to diffract a portion of the laser cavity flux out of the cavity. This increases the cavity losses and prevents from oscillation. When the RF signal is switched off, the cavity losses decrease rapidly and an intense laser pulse evolves.