Speckle-Metric-Optimization-Based Adaptive Optics for Laser Beam Projection and Coherent Beam Combining

Document Type

Article

Publication Date

7-12-2012

Publication Source

Optics Letters

Abstract

Maximization of a projected laser beam’s power density at a remotely located extended object (speckle target) can be achieved by using an adaptive optics (AO) technique based on sensing and optimization of the target-return speckle field’s statistical characteristics, referred to here as speckle metrics (SM). SM AO was demonstrated in a target-in-the-loop coherent beam combining experiment using a bistatic laser beam projection system composed of a coherent fiber-array transmitter and a power-in-the-bucket receiver. SM sensing utilized a 50 MHz rate dithering of the projected beam that provided a stair-mode approximation of the outgoing combined beam’s wavefront tip and tilt with subaperture piston phases. Fiber-integrated phase shifters were used for both the dithering and SM optimization with stochastic parallel gradient descent control.

Inclusive pages

2802-2804

ISBN/ISSN

0146-9592

Comments

© 2012 Optical Society of America. One print or electronic copy may be made for personal use only. Systematic reproduction and distribution, duplication of any material in this paper for a fee or for commercial purposes, or modifications of the content of this paper are prohibited.

Permission documentation is on file.

Publisher

Optical Society of America

Volume

37

Issue

14

Peer Reviewed

yes


Share

COinS