Novel optical vibration sensor using external cavity feedback: Novel optical vibration sensor using external cavity feedback

A novel low cost, non-contact optical vibration sensor requiring only a sin gle optoelectronic component has been developed. It consists of a continuou s wave semiconductor laser operating with external optical feedback. Vibrat ions have been measured at frequencies of up to 600 Hz with target reflecti vities lower than 5%. When calibrated, the sensor demonstrates satisfactory output for submicron vibration amplitudes. Accuracies of 0.2% have been ob tained over a range of 1 mm.