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Updated: Jul 9, 2026

Shaping the Amplitude and Phase of Laser Beams by Using a Phase-only Spatial Light Modulator

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Published on: January 28, 2019

Adaptive phase distortion correction in strong speckle-modulation conditions.

M A Vorontsov, G W Carhart

|November 23, 2007

Summary

Adaptive optics improve laser beam control by using new beam-quality metrics. This technique enhances laser energy concentration on distant objects, even with challenging atmospheric conditions like speckle.

Area of Science:

Optical Engineering
Laser Physics
Remote Sensing

Background:

Adaptive optics systems are crucial for precise laser beam control.
Laser beam propagation through the atmosphere is affected by intensity modulation due to speckle.
Accurate estimation of beam energy concentration on remote targets is challenging.

Purpose of the Study:

To introduce novel beam-quality metrics for adaptive wave-front control.
To enable estimation of laser beam energy concentration on extended objects using backscattered intensity.
To demonstrate improved laser beam concentration through adaptive correction.

Main Methods:

Development of beam-quality metrics based on backscattered wave intensity.
Implementation of a 37-control-channel adaptive optics system with phase correction.

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Last Updated: Jul 9, 2026

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Sample Drift Correction Following 4D Confocal Time-lapse Imaging

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Optimization of speckle-field-based metrics using stochastic parallel gradient descent.

Main Results:

The adaptive optics system effectively corrects phase distortions.
Speckle-field-based metrics allow for estimation of beam energy concentration.
Adaptive wave-front correction significantly enhances laser beam concentration on extended objects.

Conclusions:

Novel beam-quality metrics enable effective adaptive wave-front control.
The presented adaptive optics system overcomes speckle-induced intensity modulation.
This approach substantially improves laser targeting accuracy for remote extended objects.