Laser Optical Detection of Elastic Waves Travelling in Metallic Plates

Period of Performance: 01/01/1989 - 12/31/1989

$350K

Phase 2 SBIR

Recipient Firm

Industrial Quality, Inc.
640 E. Diamond Avenue, Suite C
Gaithersburg, MD 20877
Principal Investigator

Abstract

IMPROVEMENT TO OPTICAL HETERODYNE INTERFEROMETRIC ULTRASONIC MEASUREMENT INSTRUMENTS ARE PROPOSED. A SUCCESSFUL PHASE I EXPERIMENTATION EFFORT ILLUMINATED SEVERAL KEY MODIFICATION REQUIREMENTS OF AN ALL-FIBER INTERFEROMETRIC INSTRUMENT. THE MODIFICATIONS WILL PROVIDE INCREASED SENSITIVITY, CONDITIONS FOR EASIER USE OF THE MEASUREMENT EQUIPMENT, AND EXTENSION OF THE MEASUREMENT CAPACITY TO IN-PLANE ULTRASONIC DISPLACEMENTS. IN ADDITION TO THE DEVELOPMENT AND DEMONSTRATION OF A NEW INSTRUMENT, A COMMERCIALLY AVAILABLE FREE-PATH OPTICAL INTERFEROMETER WILL BE MODIFIED AS WELL, AND USED FOR COMPARISON STUDIES. THE FREE-PATH INTERFEROMETER WILL BE USED AS A QUALITY REFERENCE TO SURPASS WITH THE ALL-FIBER DEVICE. IN ADDITION, IT WILL BE MODIFIED FOR EASE OF ALIGNMENT SINCE THE INNOVATION PROVIDING THIS TO THE ALL-FIBER DEVICE WILL BE COMPATIBLE WITH BOTH INTERFEROMETERS. THE IMPROVED SENSITIVITY OF THE LASER MEASUREMENT APPROACH MAKES THE SYSTEM USEFUL FOR PRACTICAL MATERIALS.