The exact modes of formation of near-field reflected caustics (EN)

Theocaris, PS (EN)

Philippidis, TP (EN)

An improved experimental arrangement for recording reflected caustics created by lateral deflections of a loaded plate was introduced by the authors in the past. According to this optical system, the manifold of light-rays impinging on the loaded specimen after reflection on its front surface, is refracted upon a thin convergent lens. Then, a reversing phenomenon appears in the 3-D caustic surface which, after refraction, develops altogether another branch. Exact equations for optical image formation were derived in this paper. For two example problems, it was shown that theoretically plotted caustics, possessing generatrix curves, initials, in the near field, i.e. in the close vicinity of the stress singularity or the geometrical discontinuity, deviate either strongly from the respective caustics of the simplified far-field theory or not at all, depending on the components of the gradient vector of the deformed surface. Moreover, it was certified for another time, that, the simple and manageable equations of far-field caustics retain their validity when the respective initials lie outside of a well-defined region surrounding the singularity. Thorough experimental studies corroborated excellently theoretical findings. © 1989. (EN)

journalArticle (EN)

Optics--Geometrical (EN)

Far Field Caustics (EN)

Fracture Mechanics (EN)

Mechanics (EN)

Near Field Reflected Caustics (EN)

Surfaces--Optical Properties (EN)

Near Field (EN)

Geometrical Discontinuity (EN)

Plates (EN)

National Technical University of Athens

Digital Library of National Technical University of Athens | Dspace@NTUA

Κεντρική Βιβλιοθήκη Ε.Μ.Π.

Ιδρυματικό Αποθετήριο

Δημοσιεύσεις μελών Δ.Ε.Π. σε περιοδικά

Engineering Fracture Mechanics (EN)

English

1989 (EN)

http://hdl.handle.net/123456789/10118

33 (EN)

0013-7944 (EN)

10.1016/0013-7944(89)90070-2 (EN)

5 (EN)

732 (EN)

ISI:A1989AH21000006 (EN)

719 (EN)

PERGAMON-ELSEVIER SCIENCE LTD (EN)