The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 27, 1994
Filed:
Apr. 09, 1993
Gerard L Rafanelli, Fountain Valley, CA (US);
Brent L Ellerbroek, Albuquerque, NM (US);
Susan B Mount, Toorance, CA (US);
Mark J Rehfield, Ranch Palos Verde, CA (US);
Hughes Aircraft Company, Los Angeles, CA (US);
Abstract
An extended scene wavefront sensing apparatus and procedure that separates (deconvolves) scene effects from wavefront errors of an optical or similar system. The present wavefront sensing apparatus and procedure uses a point source wavefront slope sensor in scene scanning mode and estimates wavefront errors by using a cross-correlation or cross-coherence procedure that operates on the outputs of the point source wavefront slope sensor. A signal processing procedure employed by the point source wavefront slope sensor provides output signals corresponding to wavefront slopes at forward optics pupil locations geometrically projected to the location of the transmission and reflection measurement plane detector pairs. During the scanning process, each of the detector pairs (equivalent to a subaperture) measures the effects of the local unchanging wavefront error in the forward optical system and temporal variations due to the scanning scene. By cross correlating or cross-cohering each detector pair's temporal difference with differences from selected reference detector pairs, the scene induced variations in the measurement are eliminated, thereby leaving the stationary wavefront error component of the measurement. The lead/lag time in the temporal differences output between detector pairs and reference detector pairs are then used to estimate the wavefront slope differences between equivalent subapertures. The wavefront slope differences are used in a reconstructor to generate wavefront errors or wavefront slope errors, except for an unobservable global tilt.