SELF-DIFFRACTION SYSTEM AND METHOD OF DETECTING SMALL DISPLACEMENTS Russian patent published in 2005 - IPC

FIELD: measuring engineering.

SUBSTANCE: self-diffraction system comprises source of coherent radiation, collimator, light splitter, mirror, photodetector, signal level recorder, reverse light-sensing medium positioned in such a manner to allow the two beams, which are obtained from the collimated laser beam at the light-splitter, to be brought together with the mirror. The converging beams define a dynamical hologram, which provides self-diffraction. The method comprises forming irregular spatial interferential field with two converging coherent beams, recording the dynamic hologram in the reverse light-sensible medium, which is capable to provide self-diffraction, converting the intensity of one of the self-diffracting beams into electrical signal with the use of a photodetector, measuring the amplitude of variations of the electric signal from one photodetector with respect to the signal level which has been reached by the moment of perturbation, and detecting small displacements from the drop of the value of diffraction efficiency with respect to the level of signal which has been reached to the moment of perturbation.

EFFECT: enhanced sensitivity and simplified design.

2 cl, 1 dwg