Theory of Optical Image Improvement
Abstract
This report outlines a general theory of feedback systems designed to compensate the image-degrading effects of atmospheric seeing in real time. 'Real time' means that the optical surfaces must move rapidly enough to keep the image in sharp focus at each instant. The report demonstrates that a system producing diffraction-limited resolution in a large ground-based telescope is possible, in principle. The field of sharply focused view is very narrow (of the order of 10 seconds of arc), and the system can work only with moderately bright objects (about magnitude 10 or brighter). Secion I presents a general discussion and summary of results. Section II continues with a rigorous solution of the problem of the design of an optimum feedback system for stabilizing the phases in a simple two-beam optical interferometer perturbed by a fluctuating atmosphere. The same method of optimization is applied to the design of complete image-improvement systems in the remainder of the report. In Sections III through VI a system for real-time correction of atmospheric seeing in an optical telescope is described in detail. Sections VII through X cover the same ground as Sections III through VI. No new physical principle is introduced, but the theory of single-image optical improvement systems is recast into a form that is mathematically more precise and more general.
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 01, 1975
- Accession Number
- ADA009803
Entities
People
- F. J. Dyson
Organizations
- SRI International