Use of Holographic Linear Fringe Linearization Interferometry (FLI) for Detection of Defects.

Abstract

This report describes the progress during Phase I on the two step Holographic Fringe Linearization Interferometry (FLI) Study. The FLI process consists of deflecting the object beam between holographic exposures to create linear fringes and spatially filtering of the image reconstructed from the hologram to discriminate between subsurface defects and random fringe noise. The fringe localization procedures utilized to put the linear fringes on the surface of interest are described. The design of the repeatable thermal deformation procedures used in the preliminary experiments are discussed. The design of both the holographic recording, reconstruction and spatial filtering systems are given. Preliminary experimental results show the separation of linear fringe information and random noise in the Fourier plane of the spatial filtering system. Various filter designs which enhance the images are also discussed. System feasibility is demonstrated for a triple exposure experiment in which controlled noise was added with a third exposure. Controlled loading experiments are shown to agree with the results predicted analytically with a simple bending finite element model. Plans for the work in Phase II are presented. (Author)

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Document Details

Document Type
Technical Report
Publication Date
Apr 01, 1983
Accession Number
ADA129323

Entities

People

  • Donald A. Servaes
  • George O. Reynolds
  • John G. Develis
  • Ronald A. Mayville

Organizations

  • Honeywell International, Inc.

Tags

Communities of Interest

  • Air Platforms

DTIC Thesaurus Topics

  • Bending Moments
  • Electro-Optics
  • Fabrication
  • Frequency
  • Frequency Shift
  • Geometry
  • Image Processing
  • Interferograms
  • Interferometry
  • Laser Beams
  • Lasers
  • Materials
  • Phase Modulation
  • Photographs
  • Plane Waves
  • Shape
  • Simulations

Fields of Study

  • Physics

Readers

  • Calculus or Mathematical Analysis
  • Optical Physics and Photonics.
  • Structural Health Monitoring of Composite Structures.