1 October 1980 An Optical Open Area Ratiometer
Author Affiliations +
Abstract
An optical method for measuring the percent of open area of perforated sheet materials is presented. The technique, which is based on Fourier optics, uses a detector to measure a small central portion of the light in the Fraunhofer diffraction pattern of the perforated sheet. This approach offers accuracy and speed while avoiding diffraction problems associated with arrays of small holes. In addition it can be used with translucent materials. A brief theoretical analysis is presented as well as results obtained with a laboratory system. The system is being developed to inspect perforated materials fabricated for use on noise suppression systems for aircraft engines, however, it should be useful in the general noncontact determination of the open area of perforated materials.
Fred M. Dickey, Fred M. Dickey, Mark A Petersen, Mark A Petersen, } "An Optical Open Area Ratiometer," Optical Engineering 19(5), 195793 (1 October 1980). https://doi.org/10.1117/12.7972605 . Submission:
JOURNAL ARTICLE
4 PAGES


SHARE
RELATED CONTENT

Optical Open-Area Ratiometer
Proceedings of SPIE (May 27 1980)
Needle Points And Spread Functions
Proceedings of SPIE (November 20 1977)

Back to Top