Predetection Compensated Imaging
Abstract
This report describes the techniques developed and evaluated for predetection compensated imaging systems to measure and correct wavefront distortions at a telescope aperture. One approach to compensate these wavefront distortions is to introduce the appropriate (real-time) wavefront correction ahead of the image formation process. We call systems that achieve such corrections Imaging COAT (coherent Optical Adaptive Techniques) systems, since they are spatially coherent systems. Two general classes of wavefront error sensors have been identified and explored in this study. We have also examined several wavefront perturbation techniques (multidither techniques) that allow a detector to operate in a time shared mode to collect the wavefront error data that would normally require the use of several detectors using a nonperturbation mode of operation. This technique has been developed and refined into the Multiple Aperture InterLinked (MAIL) predetection compensation system. When advantageous, we use the MAIL concept for predictive track of multiple phase layers to obtain an extended integration time; otherwise, we rely on 'quick looks' of the phase error while viewing a bright target.
Document Details
- Document Type
- Technical Report
- Publication Date
- Apr 01, 1976
- Accession Number
- ADA025190
Entities
People
- C. J. Swigert
- D. Y. Tseng
- S. Wandzura
- T. R. O'meara
- W. P. Brown
Organizations
- HRL Laboratories