New methods for recording and processing high frequency moire patterns.

Two techniques for enhancing the potential of high frequency moire interferometry are investigated. A high frequency Ronchi grating is transferred from a silicon wafer to a test specimen. Results indicate that Ronchi (square-wave) gratings may be used to provide variable sensitivity, and that gratings of nearly any shape and size can be deposited on the surface of a specimen. Further work is suggested to refine the technique. In addition, an automated technique for analyzing surface displacement related fringes generated by moire interferometry is described. The method relies on the introduction of a carrier fringe pattern to achieve fringe linearization, and the application of image digitization and computer analysis to determine the magnitude and direction of a specific displacement component.