METHOD FOR DETERMINATION OF DEFORMATIONS BASED ON SPECKLE-PHOTOGRAPHY Russian patent published in 2019 - IPC G01B11/16 G01B9/02 

FIELD: defectoscopy.

SUBSTANCE: method relates to non-contact optical methods of investigating deformations. Method of measuring deformations consists in the fact that the object is illuminated with coherent light, speckle photography of the object is recorded before and after its deformation, the obtained combined speckle photo is scanned and the Moire pattern is determined, from which the deformation of the object is determined. In the plane of the input aperture of the optical system for recording speckle photographs, there is an annular aperture diaphragm having the form of two concentric circles with radii b and δb, where 0.9≤δ<1, registration of speckle-pictures of an object before and after its deformation is carried out simultaneously on two photoplates tightly combined with an emulsion to each other, and scanning of the combined speckle photo is carried out with one narrow beam of coherent light.

EFFECT: eliminating the error caused by the non-uniform diffractive halo shape of the Young’s bands, high sensitivity and wider range of measured deformations.

1 cl, 6 dwg