Technique for analyzing deformation in a test specimen
Abstract
Abstract APPARATUS FOR ANALYZING DEFORMATION IN A TEST SPECIMEN. WHEN AN IMAGE OF A MASTER GRID IS SUPERPOSED ON A CONGRUENT WORKING GRID OF A TEST SPECIMEN OR, CONVERSELY, THE WORKING GRID IS SUPPERPOSED ON THE MASTER GRID, AND THE SPECIMEN IS DEFORMED, SUCCESSIVE FRINGES APPEAR WHICH ARE ESSENTIALLY PARALLEL TO THE GRID LINES. A BARRIER IN THE FORM OF AN OPAQUE ELEMENT IS POSITIONED BETWEEN THE MASTER GRID AND THE SPECIMEN SO AS TO OBSCURE PART OF THE IMAGE. IN ONE POSITION OF THE OPAQUE ELEMENT, ONE SET OF A RESULTING DISPLAY OF FRINGES APPEARS AS COLORS OF A SPECTRUM AND THE OTHER SET APPEARS IN BLACK AND WHITE, IN ANOTHER POSITION OF THE OPAQUE ELEMENT, ONLY ONE SET OF FRINGES IS APARENT IN BLACK AND WHITE.
Inventors
- 👤 Cletus R Schwallie
Bibliographic Details
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