Small ZLG triax technology

Changing world politics and the advent of the Global Positioning System have resulted in a growing need for very compact guidance and control instruments designed for precision pointing and tracking, pinpoint strikes and accurate target discrimination. Requirements for these systems are not compatible with conventional dithered ring laser gyro technology and are too stringent in terms of random walk versus size for any projected fiber optics systems. However, Litton's Zero-Lock® ring laser gyro (ZLG®) technology, with its mechanically quiet environment and high resolution capabilities, is well matched to this growing arena of applications. We present design details and some preliminary test data from a couple of novel configurations for our ZLG. These designs both package three nonplanar light rings with orthogonal sensing axes into a single easy-to-manufacture glass block, in one case using only four mirrors for all three axes. Using recent advances in our coating technology, we are able to simplify the biasing arrangement for these three-axis systems, and with careful discharge layout we have reduced instrument volume considerably. Test data from an 11 cm path length frame show excellent random walk and scale factor performance with high resolution output.