Construção de sistema de travamento de frequência para laser de diodo

Abstract

The diode laser, currently, has been the most used type of laser in several areas due to its low cost of operation and especially the ease in the control process and wavelength of its service. To operate it, it needs a good stabilization in its frequency, which is important not only for measurements that require high spectral resolution, but also for several research applications. For frequency stabilization of a diode laser, an automatic frequency control loop can be used. An error signal generated by the laser frequency change must be processed (amplified and filtered) and must be fed back in order to compensate for the fluctuation in frequency. The present study aims to build a circuit for frequency locking of an absolute frequency diode laser, using a synchronized detection. To lock the laser frequency, a frequency discriminator is used as a reference which will have an equally resonant transfer function. In order to be able to lock the laser frequency to the frequency of the discriminator method used, which makes it possible to generate a derivation of the transfer function of the discriminator. This method consists of simplifying a step much in the frequency of the laser to the laser light, separating it only with a small modular step, which is being broken down into at least modulation.