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:
Jul. 01, 1980
Filed:
Sep. 07, 1978
Victor A Misek, Hudson, NH (US);
Sanders Associates, Inc., Nashua, NH (US);
Abstract
A high speed, two dimensional phase gradient map of atmosphere-induced phase gradients measures the distortion of an optical beam transmitted through the atmosphere. This is accomplished by detecting phase gradients of an interference pattern produced by optically heterodyning a returned glint from a remote target with a portion of the transmitted beam. The phase gradients are utilized to assign conjugate corrective phase distortion values to COAT actuators to alter the phase structure of the waves at the transmitter aperture. In one embodiment, two interference patterns are formed with one pattern phase shifted by 90.degree. with respect to the other. The phase gradients and their direction are detected as a function of position across the transmitter aperture by the use of two optical scanners driven in synchronism to scan the respective interference patterns. An electrical phase shifter is used in one channel along with sum and differencing units and an up-down counter to detect both the amplitude and direction of the phase gradients. This information is used to position wavefront correcting mirrors in the transmitter aperture to cancel out atmospheric distortion by properly predistorting the transmitted beam.