الفهرس 
Optical modulatorOnly 14 pages are availabe for public view
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Abstract
An acousto-optic modulator (AOM), also called a Bragg cell, uses the acousto-optic effect to diffract and shift the frequency of light using sound waves (usually at radio-frequency). They are used in lasers equipment for electronic control of the intensity and positioning of the laser beam for Q-switching, telecommunications for signal modulation, and in spectroscopy for frequency control.
Acousto optic modulation of the incoming light can be achieved by varying the amplitude and frequency of the acoustic waves traveling through the crystal. Due to the Bragg diffraction the laser beam changes its direction slightly. Therefore, one has to distinguish between the “transmission” in the original beam direction and the “efficiency” which gives the fraction of the original beam diffracted into the first order beam.
The intensity of the sound wave determines the efficiency of the Acousto optic modulator (AOM) and is therefore used to modulate the light intensity.
The switching speed of an AOM is limited by the time the sound wave needs to cross the beam diameter. So in order to achieve fast modulation, the beam diameter has to be small which on the other hand generates a conflict between the light intensity and the laser induced damage threshold of the modulator.
This thesis has presented the important transmission characteristics of AOM for high speed device and improved performance efficiency such as transmission efficiency, 3-dB bandwidth, modulation frequency, rise time, diffraction efficiency, switching time, transient time response, switching speed, power width product, total pulse broadening, transmission bit rates and modulation bandwidth with using maximum time division multiplexing (MTDM) and non return to zero (NRZ) coding under wide range of the affecting parameters.