SEDL / STP / STP1318-EB / STP11898S

New Developments in Full Field Strain Measurements Using Speckles

Chiang, F-P
Leading Professor and Chair, State University of New York at Stony Brook, Stony Brook, NY

Wang, Q
Research Assistant, State University of New York at Stony Brook, Stony Brook, NY

Lehman, F
Principle Engineer, Instron Corporation, Canton, MA

Pages: 14    Published: Jan 1997

Download this paper for $25 PDF (684K)          View License Agreement
Abstract

Speckle photography is a versatile full field technique for measuring displacement and strain. However, the wet photographic process and tedium of fringe analysis had made it impractical for application to industrial problems. This paper describes a recent development of combining digital recording and image analysis that has rendered the technique a practical tool. In addition, through the development of SIEM (Speckle Interferometry with Electron Microscopy) the technique has been extended into micromechanics domain whereby strain fields within a region only a few micron square can be mapped with confidence. Several examples of this application are presented.