Christopher A Patrick

US Patent:

7286209, Oct 23, 2007

Filed:

Feb 3, 2006

Appl. No.:

11/346156

Inventors:

Francis W. Hopwood - Severna Park MD, US
John H. Glezen - Woodbine MD, US
Michael M. Fitelson - Columbia MD, US
George R. Gray - Eldersburg MD, US
Christopher M. Patrick - Sykesville MD, US

Assignee:

Northrop Grumman Corporation - Los Angeles CA

International Classification:

G01C 3/08
H01S 3/10
H01S 3/13

US Classification:

356 401, 356 28, 372 26, 372 29011

Abstract:

An arrangement for generating a high power optical radar beam. The arrangement includes first and second laser sources each having a first laser for generating an optical beam of a relatively low frequency F and a second laser for generating an optical beam of relatively higher frequency F. Each laser source provides a first optical beam of frequency F and a second optical beam of frequency F+F. The arrangement also includes first and second waveform generators each having a modulator and a mixer. A first waveform generator receives the optical beams from the first laser source and a modulation signal for modulating the F+F optical beam. The first waveform generator is operative to provide an output optical beam of frequency F having all of the modulation applied to the optical beam of frequency F+F. A phase comparator receives the outputs from the waveform generators and if they deviate in phase, a feedback device applies a corrective signal to the modulator of the second waveform generator until the two output signals are identical. When they are identical, the phase comparator is operable to provide an output optical beam which is the coherent addition of its two input optical beams.