Phased array combination of laser beams

US4794345A · kind A · utility

Assignee

• TRW Limited · US

Inventors

• Gary J. Linford · Gardena, US
• Robert Aprahamian · Hermosa Beach, US
• Leonard J. Marabella · Torrance, US
• Jesper Munch · El Segundo, US
• Richard H. Moyer · Lomita, US
• Gabriel G. Lombardi · Redondo Beach, US

Key dates

• Filing date: Feb 26, 1986
• Grant date: Dec 27, 1988
• Expiry date: Feb 26, 2006

Classification

• Technology area (CPC H): Electricity
• CPC primary: H01S3/08059
• WIPO field: Optics
• WIPO sector: Instruments

Abstract

Apparatus, and a corresponding method for its use, for producing a phased array of high-energy laser beams from multiple laser amplifiers. A reference beam produced by a master oscillator senses phase and piston errors in a primary mirror array, and is divided into multiple probe beams, each of which makes multiple passes of its own laser amplifier. The multiple probe beams are together focused into a single phase conjugation cell, which not only produces phase-conjugated reflected beams, to effect compensation for various phase aberrations, but also locks all of the reflected beams together in phase. An arrangement of a birefringent wedge and a quaterwave plate for each of the beams prevents the reflected beams from returning to the master oscillator and facilitates combining of the reflected beams for output as a cophasal array. In a preferred embodiment of the invention, this is accomplished by using the birefringent wedges to deflect each retro-reflected phase-conjugated beam onto the appropriate portion of a monolithic secondary mirror, and then to the primary mirror array.