HUMAN FACTOR PROBLEMS IN ANTI-SUBMARINE WARFARE. SONAR TARGET CLASSIFICATION USING OPTICAL INTERFEROMETRY: AN EXPLORATORY STUDY.

Abstract : This report describes a technique for analyzing sonar echoes by means of optical interferometry. An optical filter of appropriate frequency and density is placed over a target echo and rotated through a small angle until a clearly perceptible interference pattern results. Delay-line theory predicts that the interference patterns from submarine and nonsubmarine targets should differ in unique and determinable ways. The present study confirms this prediction and, in addition, develops a technique whereby the critical information can be readily perceived by an observer having little training. (Author)