Characterization of Multipoint Diffraction Strain Sensor (MISS)

Abstract

A Multipoint Diffraction Strain Sensor (MISS) with the novel feature of simultaneous strain measurement at multiple points is characterized. Unlike conventional interferometry based systems, this patented sensor uses principles of diffraction to directly measure strain at large number of points. In this sensor, a high-frequency diffraction grating is illuminated by two symmetric laser beams and the diffracted beams are sampled on a CCD camera via a micro-lens array into an array of dots. The shift of the individual dots is sensed and strains or rigid body tilt are calculated directly. This novel technique is expected to be very valuable in numerous industrial applications.