ABSTRACT
The reticle system is essentially a patter, alternately transparent and opaque regions, placed in the image plane of the optical system. The rotating reticle system has a significant limitation of loss of carrier signal for zero-tracking error. This limitation causes the tracking performance of the reticle system to deteriorate. By using the nutating reticle system, however, this limitation can be surmounted. This entry discusses the principles of the nutating systems, including the fixed reticle, the rosette scan, and the crossed-array tracker.
