Device and method to control the output power of laser diodes

A device to control the output power of a laser diode capable of being coupled to an optical fiber, comprising:

• a photodiode which acquires a characteristic signal of the power emitted by said laser diode;
• and
• a digital laser diode driver capable of receiving and processing said characteristic signal to give a current drive signal so as to maintain a constant luminous output power of said laser diode, said driver comprising memorizing means and a central processing unit associated with a servo-control computation program for carrying out a servo-control of the output power on the basis of two levels of power emitted by said laser diode and two levels of power given by the recorded characteristic parameters of said laser diode, maintaining a constant output power despite changes in drift and change of slope of said characteristic signal of said laser diode in response to aging phenomena or to a change in temperature or to a loss of power due to the coupling of said laser diode with an optical fiber or to variations in the response of the photodiode as a function of the temperature.