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:
Jun. 12, 1990
Filed:
Oct. 17, 1986
Gary J Swanson, Lexington, MA (US);
James R Leger, Groton, MA (US);
Michael K Holz, Newton Centre, MA (US);
Massachusetts Institute of Technology, Cambridge, MA (US);
Abstract
A technique for coherent aperture filling by amplitude phase exchange is described which suppresses the far field side lobes of an array of lasers. The power contained in these side lobes is transferred to the central lobe so that it contains greater than 90% of the total array power. This is achieved by a field transformation which generates from the uniform phase and varying amplitude distribution of the input array a varying phase modulation with nearly uniform, i.e., aperture filled, amplitude distribution in the output beam. Far-field grating lobes from the nonuniformity in phase are then suppressed by an additional phase correcting element matched to compensate the phase modulation. In a preferred embodiment, the field transformation element, including a single step binary phase shifter flanked by a pair of lenses in an a focal imaging configuration, is followed by a binary phase grating for phase compensation.