Research on Auto-control of Bias Voltage of High Speed EOM

An adopted auto control of bias voltage of Electro-optical modulator(EOM) is adopted to innovate the traditional manner that gives a constant voltage to the Electro-optical modulator.The use of auto-control of bias voltage makes EOM could have a good effect at different temperatures to acclimate all kinds of environment,in this way the bias voltage of EOM can always be at the midpoint of the zone of linearity,which can guarantee an adequate modulation without any distortion.The photoelectric detection and error analysis are adopted to judge and identify the shifting of the half voltage of EOM.Then PID control algorithm is used to realize a high precision auto-control.Finally,the EOM with the auto-control is applied to the EO modulation crystal to perform a high-speed modulation experiment.