Laser Fiber Vibrometry at 1550nm Telecommunication Wavelength

In this paper we present our experiments and results connected with a laser fibre vibrometry. The main problem in this case is very low optical scattered power coming back to the system. When the fibre interferometer works on the telecommunication wavelength 1550nm it is a possibility to use the telecommunication fibre amplifier to gain weak optical signals into levels that are easily detectable. We built a couple different systems in homodyne and heterodyne schemes using standard fiber telecommunications devices for III–th optical window and EDF amplifier. Optimisation of the setup is also presented.