Optical measurement of oscillation frequencies of vibrating objects by means of the photo-EMF effect

摘要

In this work an interferometric experimental setup that allows measuring the oscillation frequencies of vibrating objects is presented, using the photo-EMF effect. Due to the high sensibility of the interferometers this system can detect oscillations in the order of some nanometers. At the moment, the system can work in a frequency interval from 500 Hz to 5 kHz. However the bandwidth can be enlarged in a very simple way by changing some electronic elements, such as resistor and capacitors.