APEs Acousto-Optic Modulator AOM modifies the intensity of laser beams, sometimes it is called Bragg Cell. Carrier Frequency MHz. The Brimrose free space Acousto-Optic Modulator (AOM) is used to control laser beam intensity, frequency modulation, frequency shifting, control pulses. An all-fiber acousto-optic modulator (AOM), which features a compact structure and a low-driving voltage, is experimentally demonstrated for.
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The acoustic waves induce a birefringent phase-shift, much like in a Pockels cell [ dubious — discuss ]. The acousto-optic tunable filter, especially the acousto optic modulatorwhich can generate variable pulse shapes, is based on this principle.
This is fast enough to create active modelocking in an ultrafast laser. When faster control is necessary electro-optic modulators are used.
However, these require very high voltages e. There are also integrated-optical devices containing one or more acousto-optic modulators on a chip.
This is possible, e. Such devices can acousto optic modulator used in many ways, e.
Applications Acousto-optic modulators acousto optic modulator many applications: They are used for Q acousto optic modulator of solid-state lasers.
The AOM, called Acousto optic modulator switchthen serves to block the laser resonator before the pulse is generated. In most cases, the zero-order not diffracted beam is used under lasing conditions, and the AOM is turned on when lasing should be prohibited.
This requires that the caused diffraction losses possibly for two passes per resonator round trip are higher than the laser gain. For high-gain lasers for example, fiber lasersone sometimes uses the first-order diffracted beam under lasing conditions, so that very high resonator losses result when the AOM is turned off.
However, the losses in the lasing state are then also fairly high. AOMs can also be used for cavity dumping of solid-state lasers, generating either acousto optic modulator or ultrashort pulses.
In the latter case, the speed of an AOM is sufficient acousto optic modulator in the case of a relatively long laser resonator; an electro-optic modulator may otherwise be required.
Active mode locking is often performed with an AOM for modulating the resonator losses at acousto optic modulator round-trip frequency or a multiple thereof.
An AOM can be used as a pulse picker for reducing the pulse repetition rate of a pulse train, e. In laser printers and other devices, an AOM can be used for modulating the power of a laser beam. An AOM can shift the frequency of a laser beam, e.
acousto optic modulator In some cases one exploits the effect that the diffraction angle depends on the acoustic frequency. In particular, one can scan the output beam direction at least in a small range by changing the modulation frequency.
Important Properties of Acousto-optic Modulators Various aspects can be essential for the selection of an acousto-optic modulator for some application: The material should have a high transparency at the relevant wavelengths, acousto optic modulator parasitic reflections should be minimized e.