METHODS FOR THE CALIBRATION OF VIBRATION PICK-UPS BY LASER INTERFEROMETRY - I - THEORETICAL-ANALYSIS

A regression analysis method is applied for data transforming and erro r evaluation in the sine-approximation method (SAM) for the calibratio n of vibration pick-ups by laser interferometry. A new simple algorith m for phase unwrapping in the SAM is also proposed. To make a more val uable comparison of this modified SAM with other techniques, i.e. the fringe counting method (FCM) and the minimum point method (MPM), the r esolution of the measuring system is increased by using a double optic al path difference homodyne interferometer. Additionally the uncertain ty ct the FCM is suppressed by implementing the procedure of fringe ph ase analysis in the turning points of the vibration cycle. This paper presents a theoretical analysis of the above mentioned problems.