Abstract

The theory associated with using a guide star beacon in a different direction than the direction associated with an object is discussed in detail. It is shown that conventional anisoplanatism does not significantly degrade the performance of a synthetic guide star. The theoretical predictions are shown to be in agreement with the results of a guide star imaging experiment used to view binary stars. This work concludes with a discussion of an advanced concept that utilizes an optimal estimator to combined wavefront sensor data from a nearby guide star several isoplanatic patch sizes away from the object and wavefront sensor data from an artificial guide star to compensate the image. The results of this work illustrate that the typical D^5/3 (where D is the telescope diameter) scaling law for mean-squares wavefront error is no longer obeyed when this approach is used. As a consequence, this technique allows one to compensate telescopes with diameters larger than what would normally be the case with conventional guide star imaging techniques.

© 1991 Optical Society of America