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Beam Formation and Vernier Steering Off of a Rough Surface
Eric K Nagamine1, Kenneth W Burgi1, Samuel D Butler1
1Air Force Institute of Technology, 2950 Hobson Way, Dayton, OH 45433, USA.
Micromachines
|August 27, 2021
Summary
Wavefront shaping refocuses light using rough surfaces for indirect imaging. A genetic algorithm outperformed other methods, enabling precise beam steering for enhanced illumination control.
Area of Science:
- Optics
- Photonics
- Computational Imaging
Background:
- Wavefront shaping enables light refocusing after reflection from rough surfaces.
- This capability is key for indirect imaging, potentially turning surfaces into illumination sources for non-line-of-sight objects.
Purpose of the Study:
- To demonstrate the superior performance of a genetic algorithm (GA) for wavefront shaping in reflective inverse diffusion.
- To investigate the precise control of the refocused beam's pointing direction.
Main Methods:
- Utilized a genetic algorithm for iterative feedback-based wavefront shaping.
- Implemented a focal plane system to achieve reflective inverse diffusion.
- Demonstrated beam steering for controlling the refocused beam's direction.
Main Results:
- The genetic algorithm showed superior performance compared to other iterative algorithms for reflective inverse diffusion.
- High-precision control of the refocused beam's pointing direction was achieved over a narrow angular range.
- The challenge of increasing the overall scanning range of the refocused beam persists.
Conclusions:
- Genetic algorithms offer an effective approach for wavefront shaping in indirect imaging applications.
- The demonstrated beam steering method can complement existing coarse adjustment techniques for enhanced illumination control.
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