One of the main components of the optical communication lines via optical fibers, even multi-core fibers is a semiconductor laser, which is located in the transmitter and transmits the light into the optical fiber. For proper operation, laser requires the electronics to prevent alteration as a function of temperature, meanwhile the system maintain constant output optical power. Temperature stabilization electronic circuit can automatically stabilize the temperature of the laser module to the pre-set value which means, that our desired output power and wavelength will be the same when transmitting. And one more thought, if we look at the optical power when laser is emitting light, certain amount of electrical energy converts to heat. And once again, we must control this thermal energy.
First we present some basics of DFB lasers and it's characteristics, and then how the change in the temperature affects the output power and the wavelength. Step forward is our approach to some methods how to stabilize the temperatures, so the system can work efficiently. After theory, we describe some typical procedures that we have resorted such as manufacturing processes and measurement procedures. When we want to stabilize the temperature, the important circuit is the PID controller, which was also done in laboratory, result is short time of stabilization and constant output power. I describe and discuss the results of testing the output power, wavelength and temperature stabilization, what we have achieved and compare our stabilization with the work that was conducted in the past.
|
