Nondestructive Testing Using TRW Acousto-Optical Imaging System

Abstract

The technique of Acousto-Optical Imaging (AOI) enables one to 'see', on a real-time basis, within optically opaque materials and to detect internal or surface flaws and/or other irregularities which might be present. The process uses an ultrasonic beam to probe the object under study. As it interacts with the object, the ultrasonic beam acquires an acoustical 'picture' of the object. The acoustic waves then interact with a monochromatic light beam (as from a laser). Optical sidebands are produced by the Bragg diffraction of light. The cumulative result of this process is that these sidebands produce a visual image of the interior of the object. This paper discusses the results of an experimental study to evaluate the applicability of acousto-optical imaging to nondestructive testing. In addition to the determination of the system resolution, the effects of specimen thickness, geometry, composition and surface roughness are under investigation. A new technique which utilizes the sound reflected from the specimen to obtain an acousto-optical image was also developed. Preliminary results utilizing this technique to detect surface flaws on a specimen are encouraging.

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Document Details

Document Type
Technical Report
Publication Date
Jan 01, 1971
Accession Number
AD0723434

Entities

People

  • Jerold L. Jacoby
  • Pravin G. Bhuta
  • Robert Aprahamian

Tags

Communities of Interest

  • Air Platforms
  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Acoustic Frequencies
  • Acoustic Propagation
  • Acoustic Waves
  • Acoustics
  • Applied Mechanics
  • Closed Circuit Television
  • Diffraction
  • Films
  • Frequency
  • Light Sources
  • Mechanics
  • Nondestructive Testing
  • Refractive Index
  • Repetition Rate
  • Sound Waves
  • Standing Waves
  • Television Systems

Fields of Study

  • Physics

Readers

  • Image Processing and Computer Vision.
  • Optical Physics and Photonics.
  • Structural Health Monitoring of Composite Structures.

Technology Areas

  • Directed Energy