SLR	Satellite Laser Ranging
DLR	Debris Laser Ranging
LLR	Lunar Laser Ranging
LEO	Low Earth Orbit
GEO	Geosynchronous Orbit
TOF	Time Of Flight
PMT	Photomultiplier
APD	Avalanche Photon Diode
SPAD	Single-Photon Avalanche Diode
SNSPD	Superconducting Nanowire Single-Photon Detector
TCSPC	Time-Correlated Single-Photon Counting
SAGCM	Separate Absorption Grading Charge Multiplication
FGR	Floating Guard Ring
DCR	Dark Count Rate
PDE	Photon-Detection Efficiency
FWHM	Full Width at Half Maximum
MBE	Molecular Beam Epitaxy
MOCVD	Metal–Organic Chemical Vapour Deposition
FPGAs	Field-Programmable Gate Arrays
PQAR	Passive Quenching Active Reset
PQPR	Passive Quenching Passive Reset
PQACR	Passive Quenching Active Clock-Driven Reset