Titre du document / Document title

Optical phased array technology

Auteur(s) / Author(s)

MCMANAMON P. F. ⁽¹⁾ ; DORSCHNER T. A. ; CORKUM D. L. ; FRIEDMAN L. J. ; HOBBS D. S. ; HOLZ M. ; LIBERMAN S. ; NGUYEN H. Q. ; RESLER D. P. ; SHARP R. C. ; WATSON E. A. ⁽¹⁾ ;

Affiliation(s) du ou des auteurs / Author(s) Affiliation(s)

⁽¹⁾ Wright Laboratory, Wright Patterson AFG, OH 45433, ETATS-UNIS

Résumé / Abstract

Optical phased arrays represent an enabling new technology that makes possible simple, affordable, lightweight, optical sensors offering very precise stabilization, random-access pointing, programmable multiple simultaneous beams, a dynamic focus/defocus capability, and moderate to excellent optical power handling capability. These new arrays steer or otherwise operate on an already formed beam, as compared to modern microwave phased arrays which both generate a beam and direct it in a specific direction. A phase profile is imposed on an optical beam as it is either transmitted through or reflected from the phase shifter array. The imposed phase profile steers, focuses, fans out, or corrects phase aberrations on the beam. The array of optical phase shifters is realized through lithographic patterning of an electrical addressing network on the superstrate of a liquid crystal waveplate. Refractive index changes sufficiently large to realize full-wave differential phase shifts can be effected using low (<10 V) voltages applied to the liquid crystal phase plate electrodes. High efficiency large-angle steering with phased arrays requires phase shifter spacing on the order of a wavelength or less ; consequently addressing issues make 1-D optical arrays much more practical than 2-D arrays. Orthogonal oriented 1-D phased arrays are used to deflect a beam in both dimensions. Optical phased arrays with apertures on the order of 4 cm by 4 cm have been fabricated for steering green, red, 1.06 μm, and 10.6 μm radiation. Steering efficiencies of about 60% at 4° and 85% at about 2° have been achieved to date with switching times as short as a few milliseconds in the visible. Fluences of several hundred W/cm² have been demonstrated at 10.6 μm with nonoptimally engineered devices. Higher fluences can be handled at shorter wavelengths. Larger apertures are feasible, as is operation at other wavelengths and significantly faster switching times. System concepts that include a passive acquisition sensor as well as a laser radar are presented.

Revue / Journal Title

Proceedings of the IEEE    ISSN  0018-9219   CODEN IEEPAD 

Source / Source

1996, vol. 84, n^o 2, pp.  99-320 (76 ref.), pp. 268-2098

Langue / Language

Anglais

Editeur / Publisher

Institute of Electrical and Electronics Engineers, New York, NY, ETATS-UNIS  (1963) (Revue)

Mots-clés anglais / English Keywords

Optical radar

;

Lasers

;

Lidar

;

Phased array

;

Control

;

Laser beams

;

Liquid crystals

;

Visible radiation

;

Infrared radiation

;

Experimental study

;

Military equipment

;

Mots-clés français / French Keywords

4279Q

;

4279F

;

Radar optique

;

Laser

;

Lidar

;

Réseau en phase

;

Commande

;

Faisceau laser

;

Cristal liquide

;

Rayonnement visible

;

Rayonnement IR

;

Etude expérimentale

;

Matériel militaire

;

Déflexion

;

Mots-clés espagnols / Spanish Keywords

Red en fase

;

Localisation / Location

INIST-CNRS, Cote INIST : 222, 35400005290920.0070