Accession Number : ADD004734

Title :   Photo Electronic Direction of Motion Indicator.

Descriptive Note : Patent,

Corporate Author : DEPARTMENT OF THE AIR FORCE WASHINGTON D C

Personal Author(s) : Marko,Adolf R

Report Date : 24 Jan 1978

Pagination or Media Count : 6

Abstract : Two, adjacent, but circumferentially displaced, photodetectors radially positioned exterior to a rotating body sense the changes in the intensity of light impinging on the detectors emanating from a defined source on the periphery of the rotating body. The sequentially changing outputs of the photodetectors are compared in a comparator circuit which provides a triangular wave shape output signal having either a sharp leading edge or a sharp trailing edge depending upon the sequence of activation of the photodetectors by the rotating light signal. The triangular wave is differentiated providing either positive going spike pulses or negative going spike pulses depending on whether the rotating body was moving clockwise or counterclockwise. The output of the differentiator is displayed on an oscilloscope to visually indicate by the presence of either positive or negative going spike pulses the direction of rotation of the rotating body. (Author)

Descriptors :   *Patents, *Photodetectors, Motion, Directional, Rotation

Subject Categories : Optical Detection and Detectors

Distribution Statement : APPROVED FOR PUBLIC RELEASE