Detection method of electronic speckles for synchronous carrier-frequency modulation in three-dimensional deformation field

Abstract

The invention provides a detection method of electronic speckles for synchronous carrier-frequency modulation in a three-dimensional deformation field. The method comprises the following steps: achieving short-distance illumination of three lasers and short-distance stack imaging on an object surface to be detected and a reference object surface by adopting a large-dislocation square prism; introducing carrier fringe patterns by deflecting the reference object surface, and then carrying out one-time modulation on a speckle interference fringe field lighted by the three lasers; when bending deformation occurs on the carrier fringe patterns under modulation of objection deformation after loading an object, independently measuring the deformed object by the three lasers, collecting the carrier fringe patterns before and after object deformation and the modulated carrier fringe patterns, and then respectively demodulating the carrier fringe patterns by a Fourier transform method to obtain a three-bitmap phase diagram containing off-plane and in-plane information; and finally carrying out phase operation to separate three components of a displacement field. By using the detection method, modulation of three speckle interference fringe fields by deflecting the reference object surface is achieved to obtain high-quality modulation fringe patterns. The method has the advantages of simple light path, relatively simple operation and high measuring precision.

Description

technical field [0001] The invention relates to a method for detecting three-dimensional displacement components of carrier-frequency electronic speckle interference of deformation fields, and belongs to the technical field of measuring three-dimensional components of object deformation by carrier-frequency electronic speckle interference. Background technique [0002] In optomechanical measurement, electronic speckle interferometry technology can accurately measure the deformation field of an object. It has the advantages of high precision, non-contact, and low requirements for vibration isolation. It is widely used in static and dynamic measurement of objects. But the current typical electronic speckle interferometry technology can only measure the one-dimensional deformation of the object. Since the deformation of the object is three-dimensional, it is often necessary to measure the two-dimensional or three-dimensional deformation components of the object. Time phase shi...

AI Technical Summary

Problems solved by technology

The electronic speckle method using three measurement optical paths with carrier frequency modulation has been reported. This method modulates and demodulates the three displacement components separately, and the optical path is complicated. It is essentially a one-dimensional carrier frequency modulation.

The electronic speckle method that simultaneously modulates and demodulates three displacement components at once has not been reported yet

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