SEPARATION OF ADDITIVE AND SUBTRACTIVE MOIRE PATTERNS,

Abstract

A spatial filtering technique for observing several different moire patterns in the same image of superposed gratings and for separating them at will, is described. In addition to the commonly observed moire pattern, and the equivalent patterns obtained by fringe sharpening or multiplication, patterns can be observed that correspond to different forms of the indicial equation describing the parametric properties of moire phenomena. In particular both the additive and subtractive moires are obtained individually, over the field. This method, combined with a previously developed method for obtaining spatial partial derivatives from deformed gratings (as a direct moire rather than moire of moire), permits the experimental determination of the whole field of Cartesian shears and rigid rotations. The method is applied to a circular ring subjected to diametral compression. (Author)

Document Details

Document Type
Technical Report
Publication Date
Dec 01, 1969
Accession Number
AD0699601

Entities

People

  • Augusto J. Durelli
  • J. A. Clark

Organizations

  • The Catholic University of America

Tags

DTIC Thesaurus Topics

  • Additives (Chemicals)
  • Angular Motion
  • Compression
  • Equations
  • Filtration
  • Mathematics
  • Rotation
  • Spatial Filtering

Fields of Study

  • Physics

Readers

  • Mechanical Engineering/Mechanics of Materials.
  • Optical Physics and Photonics.
  • Phased Array Antenna Design.