METHOD OF SETTING FIXED AMPLITUDES OF VIBRATIONS Russian patent published in 2002 - IPC

FIELD: methods of setting fixed amplitudes of vibrations. SUBSTANCE: method consists in forming reference and measuring coherent radiation beams, obtaining interference field, shifting radiation frequency of one of beams relative to other beam lesser than ω/2,,where ω - is frequency of vibration of object under test; method includes also generation of signal proportional to brightness of interference field; selected parameter of signal is minimized by changing the amplitude of vibration of object under test. Magnitudes of amplitudes S are set from row S = к•λ/4, where k = 1, 2, 3, ..., where λ is length of coherent radiation wave; used as minimizing parameter is difference between two sequences of signal level which correspond to moment of successive passage of object under test through its two opposite amplitude positions. EFFECT: extended range of fixed amplitudes; simplified scheme of recording signal of photodetector. 2 dwg