Research on an Adaptive Coupling Technique for Spatially Scattered Light.

Area of Science:

• Optics and Photonics
• Laser Technology
• Ocean Engineering

Background:

• Coupling spatially scattered light from underwater LiDAR to single-mode fibers presents alignment and efficiency challenges.
• Existing methods struggle with the dynamic and diffuse nature of scattered light in underwater environments.

Purpose of the Study:

• To analyze the coupling principle of spatially scattered light and its influencing factors.
• To design and develop an adaptive coupling system for efficient underwater LiDAR light coupling.
• To improve coupling efficiency and overcome alignment difficulties in scattered light systems.

Main Methods:

• Analysis and simulation based on the extended light source imaging model.
• Development of a three-lens receiving system with a fast steering mirror and displacement stage.
• Implementation of a joint control strategy combining rough and precise alignment using an improved simulated annealing SPGD algorithm.

Main Results:

• The adaptive coupling system achieved a coupling efficiency of 88.18% of the theoretical value.
• Demonstrated an approximate 88% improvement in coupling efficiency compared to manual adjustment.
• The SPGD algorithm effectively avoided local optima, ensuring robust performance.

Conclusions:

• The developed adaptive coupling system offers a feasible and efficient solution for underwater LiDAR.
• The study provides a practical approach for scattered light coupling in similar optical applications.
• This work enhances the performance and reliability of underwater optical sensing systems.