Metodo para controlar un modulador optico, que comprende recibir una entrada optica, emitir una salida optica, proveer un objetivo para la potencia optica, aplicar un voltaje de polarizacion, detectar que una entrada optica ha sido desactivada, determinar una primera extension de tiempo en que la potencia de salida se encontraba dentro de un rango predefinido, y mantener el voltaje de polarizacion en su nivel actual durante una segunda extension de tiempo; aparato asociado.

摘要

Methods and apparatus for controlling a bias voltage (20) supplied to an optical modulator that comprises a biasable component configurable to be biased by application of the bias voltage (20), the method comprising: providing a target for the modulator output power; applying, to the biasable component, a bias voltage (20) that biases the biasable component so that the output power is within a pre-defined range of the target; monitoring the output power and, if the output power of the modulator is determined to be outside the pre-defined range, varying the value of the bias voltage (20) to bring the output power back within the pre-defined range; and monitoring the optical input to the modulator and, if it has been disabled, maintaining the bias voltage (20) at its current level for a pre-determined length of time that is dependent upon how long the modulator has been operating at quadrature.