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arXiv · 2412.11436

Event-based Detectors for Laser Guide Star Tip-Tilt Sensing

Monique Cockram·Noelia Martinez Rey
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Abstract

Event-based sensors detect only changes in brightness across a scene, with each pixel producing an asynchronous stream of spatial-temporal data, rather than recording frames of overall illumination such as a traditional frame-based sensor. This is advantageous for implementing into a wavefront sensor, which benefits from high temporal resolution and high dynamic range. The determination of tip-tilt in particular is still a problem in laser guide star (LGS) adaptive optics as there are no current technological capabilities to measure it. We characterized the behavior of an event-based sensor in the context of tip-tilt sensing, investigating if the high temporal resolution of the event streams could address these challenges. Different conditions of tip-tilt and background illumination levels are explored and found to be a strong contender for tip-tilt sensing with LGSs.

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Monique Cockram, Noelia Martinez Rey. 2024-12-16. Event-based Detectors for Laser Guide Star Tip-Tilt Sensing. https://doi.org/10.1117/1.oe.64.4.043102

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