A vernier time-interval digitizer (VTID) uses two slightly offset clock frequencies to measure time delays with picosecond resolution. By counting the number of cycles until the two clocks align in phase, the instrument interpolates the exact arrival time of a trigger signal. This technique is heavily used in particle physics, laser ranging, and high-speed radar systems.
Heard on the job
Hook the detector output to the VTID so we can get a precise timestamp on the photon arrival.