Using an incoherent target return to adaptively focus through atmospheric turbulence.

Area of Science:

• Optical engineering
• Atmospheric optics
• Adaptive optics

Background:

• Laser beams propagating through atmospheric turbulence experience intensity fluctuations.
• Cooperative targets with coherent return beams allow for phase correction using adaptive optics.
• Uncooperative targets typically provide incoherent return beams, posing a challenge for correction.

Purpose of the Study:

• To demonstrate a method for correcting laser beam intensity fluctuations using incoherent return from uncooperative targets.
• To derive a novel relation between the target field and the returned field based on the principle of reciprocity.
• To simulate an adaptive optics system capable of focusing a beam through atmospheric turbulence onto a rough surface.

Main Methods:

• Derivation of a novel relation using the principle of reciprocity.
• Simulation of an adaptive optics system.
• Utilizing incoherent target return for phase correction.

Main Results:

• A method is presented to correct laser beam intensity fluctuations from atmospheric turbulence using incoherent target return.
• A novel reciprocity-based relation is derived for adaptive optics.
• The simulated system successfully focuses a beam through turbulence onto a rough surface.

Conclusions:

• Adaptive optics can correct laser beam intensity fluctuations even with uncooperative targets and incoherent return.
• The derived reciprocity relation enables effective beam focusing through atmospheric turbulence.
• This approach offers a viable solution for laser beam control in challenging atmospheric conditions.