Engineering innovation company Draper has earned a patent for its single-photon detector to improve the way lidar systems detect vehicles and objects.
The detector uses a silicon-germanium photodiode, has ultralow dark-counting rate and timing resolution of less than one nanosecond.
The single-photon detector is the first of its kind that is capable of detecting single particles of light with high timing resolution, speed and efficiency over a longer wavelength range.
Steven Spector, principal member of Draper’s technical staff, said, “In applications like lidar, you are often limited in how much laser power you can use, but you want to be able to get a lot information from the objects in the scene. The most efficient detector you can have is one that can measure every single photon coming in to identify specific objects of interest.”
The detector can absorb and detect a single particle of light, called a photon, and refresh for the next one within nanoseconds.
Engineers designed the system as an array of photodiodes and paired them with single electron bipolar avalanche transistors that turn an incoming photon into a large electric current.