| 摘要 |
<p>The invention relates to a non-invasive method for measuring the values of the saturation fluency and of the efficient absorption cross section of a passive optical switch and a device for applying the same. According to the invention, the method allows the direct evaluation of the saturation fluency of a passive optical switch and of the efficient absorption cross section by a single measurement, by using a laser transmitter operated in regime of passive optical commutation at the work length of the assessed passive optical switch, said transmitter transmitting laser pulses of high energy, with durations, at semi-amplitude, shorter by at least one size grade than the lifetime of the electrons in the first excited energy level of the active optical centers of the passive optical switch and having a Gauss cross section distribution of the laser intensity, the thus-transmitted laser pulses are expanded by a Galilei telescope, afterwards there is selected the central part of the laser beam and, subsequently, after applying a controlled attenuation, the laser beam is transmitted through the passive optical switch to be analyzed, the energy thereof being measured by a laser energy monitor with silicon photodiode, thus there being made a measurement of the transmittance variation of the passive optical switch with the fluency incident to the laser wave length. According to the invention, the said device consists of a solid state laser operated in regime of passive optical commutation, the laser comprising: a mirror () with 100% reflectance, a polarizer (), a passive optical switch (), an active laser medium (), a diaphragm () and a mirror () for the extraction of the output laser pulses, a Galilei telescope () for expanding the beam, a circular diaphragm () for obtaining a constant cross distribution of the beam intensity, a calibrated attenuator () in order to vary, in a controlled way, the fluency of the laser pulses, a laser energy monitor (), a system for data acquisition () and a PC ().</p> |
