Study Of Measuring Method Of Laser Interference Based On LabVIEW

Detection of tiny low-frequency signal are important for practical applications, rapidadvance in engineering technology in recent years, in particular advances in areas such asaviation, marine engineering technology, he detection of tiny low-frequency signal is moreimportant. Analysis and comparison of many detection method of tiny signal, the traditionalMichelson interferometer has been improved, and is used to detect low frequency of weaksignal.This paper describes in detail fundamentals of the improved Michelson Interferometer andthe corresponding detection methods-phase generated carrier (PGC), and introduces virtualinstruments to complete the PGC demodulation. Virtual instruments combine PC with withthe featured hardware system using LabVIEW software. PC machine can be operated througha graphical interface with the way which is similar to the operation of the previous instrument.Since this method is widely used due to its easiness of operation and convenience ofdebugging.The subject make a combination of laser interferometry, virtual instruments and PC anddigital signal processing, to constitute a detection system of tiny low-frequency signal withlaser interference, of which LabVIEW is core and PC is the hardware core, characteristic ofthis system is practical, simple, high accuracy, high sensitivity.Michelson Interferometer demodulate signal with phase generated carrier, which is akind of homodyne in regular. However, noise and overload of electronic devices in analogcircuit affect the performance of detection systems. This article uses a system based on virtualinstrument for Michelson Interferometer. Compared to the previous method of hardware,temperature drift and the impedance mismatch of analog circuits can be solved with thismethod. The subject designed PGC detection system based on LabVIEW, experiment showedthat the systems can detect low frequency of weak signal, analysed final demodulated signal.