Accession Number:

AD0425706

Title:

RING LASER TECHNIQUES FOR ANGULAR ROTATION SENSING,

Descriptive Note:

Corporate Author:

AERONAUTICAL SYSTEMS DIV WRIGHT-PATTERSON AFB OHIO

Personal Author(s):

Report Date:

1963-09-01

Pagination or Media Count:

30.0

Abstract:

The concept of using a ringlaser to measure angular rotation is presented. The optical frequencies of the clockwise and the counterclockwise beams traveling around the perimeter of the square ring depend on their respective optical path lengths which are equal in the absence of rotation. However, angular rotation alters the path lengths, resulting in different frequencies for the two traveling waves. The two waves are optically heterodyned in a photodetector and the resultant beat frequency is directly proportional to the rotation rate of the ring. An experiment verifying the existence of this phenomenon using a gas laser in the square ring configuration is described. The physics of mode pulling and various ways to minimize or bypass this problem are discussed in detail. Techniques for artificially seperating the frequencies of the two waves by introduction of nonreciprocal elements into the optical paht are described. Accuracy limitations caused by mechanical instabilities, excitation variations and inherent stimulated emission line width are examined. Author

Subject Categories:

Distribution Statement:

APPROVED FOR PUBLIC RELEASE