Experimental Laboratory Setup for Single-Photon Counting Laser Altimetry in Planetary Research

Kurzfassung

Laser altimetry is a technique for precise topographic measurements of planetary surfaces, enabling deeper insights into celestial bodies within the solar system. This master’s thesis explores the potential of single-photon detection technology to enhance laser altimetry in planetary research. The research objective is to investigate a constructed experimental laboratory setup for single-photon counting laser altimetry, aiming to detect laser pulses with the minimum required number of photons. The study begins with characterizing a Single Photon Avalanche Detector (SPAD), determining its quantum efficiency and dark count rate. These parameters lay the foundation for subsequent experiments. The research introduces a method called temporal filtering, utilizing an 80 ns laser pulse to detect laser signals within a short timeframe, enhancing precision in pulse timing determination. The impact of transmission settings of the attenuators, background radiation, and afterpulsing on laser pulse detection is investigated. Results show a non-linear relationship between transmission settings, dark counts, and afterpulse generation, a↵ecting event count accuracy. Remarkably, the experimental setupdemonstrates a high sensitivity, operating at energy levels orders of magnitude lower than typical laser altimetry instruments. This research provides insights into the behavior and performance of single-photon detectors and demonstrates their potential to advance laser altimetry in planetary research. By addressing noise, background radiation, and afterpulsing challenges, this work aims to contribute to improving accuracy and sensitivity in planetary surface measurements.