OPTICAL STRAIN SENSOR AND METHOD FOR THE MEASUREMENT OF MICRODEFORMATIONS

摘要

The present invention is concerned with an optical strain sensor for measuring microdeformations of a surface with a resolution of at least 0.2 microns. The sensor comprises at least one camera for taking photographs of areas of the surface, the photographs being separated by a known fixed distance from one another before and after deformation has occured. Templates are selected on the photographs taken before deformation, relocalized on photographs taken after deformation of the surface, and the deformation is derived from the computation of the difference in distances between the templates before and after deformation has occured.