Sequential phase locking scheme for a filled aperture intensity coherent combination of beam arrays

TL;DR

This paper introduces a new phase locking method for coherently combining beam arrays in filled aperture setups, enabling synchronized control of many channels with limited bandwidth electronics.

Contribution

It proposes a phase dithering and alternating scheme that allows standard lock-in electronics to phase lock multiple beams efficiently.

Findings

Enables coherent combination of large beam arrays.

Uses standard lock-in electronics for phase locking.

Supports limited bandwidth phase actuators.

Abstract

We present a novel phase locking scheme for the coherent combination of beam arrays in the filled aperture configuration. Employing a phase dithering mechanism for the different beams similar to LOCSET, dithering frequencies for sequential combination steps are reused. By applying an additional phase alternating scheme, this allows to use standard synchronized multichannel lock-in electronics for phase locking a large number of channels even when the frequency bandwidth of the employed phase actuators is limited.