METHOD AND DEVICE FOR MONITORING THE AERONAUTICAL MECHANICAL STRUCTURAL SOUNDNESS BY USING AN OPTOELECTRONIC SENSOR OF THE ACTIVE OPTOELECTRONIC TYPE HAVING A SPATIAL MODULATION OF THE CORE REFRACTIONINDEX

摘要

The invention relates to a method and a device for monitoring the aeronautical mechanical structural soundness, without affecting the flight or utilization characteristics. According to the invention, the method consists in using a pumping laser diode which injects a pumping laser radiation with a certain spectral power distribution through a multiplexer dividing the wave length in the mono-mode optical fibre doped with trivalent erbium ions, Er, in whose core there is induced a Bragg diffraction network which ensures, by reflection, the distributed reaction necessary for generating the laser effect with a spectral distribution different from that of the pumping laser radiation and which varies depending on the size of the force applied to the optical fibre, said force corresponding to the mechanical stress created in the mechanical structure to be monitored. The claimed device consists of a laser diode (1), a multiplexer (2) dividing the wave length, an optical fibre in whose core there is induced a Bragg network (3), a photodiode (4), an amplifier (5), a data acquisition system (6) and a computer (7).