Accurate photo detector measurements for LIDAR

A light ranging system comprising:

• a light source configured to provide pulses;
• a sensor integrated circuit that includes:
• a plurality of photosensors corresponding to different fields of view, each photosensor of the plurality of photosensors including a plurality of photodetectors that when triggered by photons are configured to output binary signals indicating the photons have been detected;
• timing circuitry configured to determine times for when photons are detected based on the binary signals;
• and
• histogram circuitry configured to determine and store counters that each correspond to a number of photodetectors of a photosensor triggered during a time bin for each photosensor of the plurality of photosensors, thereby creating a histogram that is usable to determine a received time of one or more pulses from the light source that reflected from an object to each photosensor of the plurality of photosensors.

An optical measurement system comprising:

• a light source configured to provide pulses;
• a photosensor;
• and
• circuitry configured to:
• transmit N pulse trains from the light source as part of an optical measurement, each of the N pulse trains including one or more pulses from the light source and corresponding to a different time interval that is triggered by a start signal, and wherein N is an integer greater than one;
• detect photons of the N pulse trains by the photosensor of the optical measurement system, thereby generating data values at a plurality of time points;
• for each of the N pulse trains, assign a weight to the data values at time points within the time interval corresponding to the pulse train, thereby obtaining weighted values, wherein at least two of the N pulse trains are assigned different weights and have different pulse patterns;
• determine a histogram corresponding to the weighted values in a plurality of time bins, wherein a determining counter of the histogram at a particular time bin includes accumulating the weighted values at time points within the particular time bin across a plurality of time intervals;
• and
• detect a signal corresponding to the N pulse trains within the histogram.