| 摘要 |
<p>A surface on which there is a regular periodic pattern, often a relief pattern (12), is deformed, and in-plane deformation is sensed by illuminating the deformed pattern with a beam (12) of coherent light so that light is reflected as one zero order beam and a plurality of diffracted beams, and combining two of the beams (16, 18) so that they interfere in a manner related to the deformation along the direction of intersection of the surface plane with the plane in which the two interfering beams lie. The magnitude and direction of in-plane deformation in one or more directions and the magnitude and direction of the maximum in-plane stress or strain, can be determined automatically.</p> |
