Scanning Laser Devices and Methods with Multiple Range Emission Control Pulse Sets

An apparatus comprising:

• a laser light source configured to produce laser light pulses;
• an optical assembly, the optical assembly including beam scanning optics to scan the laser light pulses to measurement points in a scan field;
• a detector to detect reflections of the laser light pulses from the measurement points in the scan field;
• a time-of-flight (TOF) circuitry responsive to the detector to determine distances to the measurement points in the scan field from the detected reflections;
• a light source controller coupled to the laser light source and the detector, the light source controller adapted to control the laser light source to, for each measurement point in a plurality of the measurement points:
• emit a first emission control pulse set at a reduced first energy level to detect objects within a first safety range;
• responsive to not detecting an object within the first safety range with reflections of the first emission control pulse set, emit a second emission control pulse set following the first emission control pulse set and at a reduced second energy level to detect objects within a second safety range, where the second safety range extends further than the first safety range, and where the reduced second energy level is greater than first energy level, otherwise proceeding to a next measurement point in the plurality of the measurement points in the scan field;
• responsive to not detecting an object within the first safety range with reflections of the first emission control pulse set and to not detecting an object within the second safety range with reflections of the second emission control pulse set, emit a ranging pulse set at a higher energy level where the higher energy level is greater than the reduced first energy level and the reduced second energy level, then proceeding to the next measurement point in the plurality of the measurement points in the scan field;
• and
• responsive to detecting an object within the first safety range with reflections of the first emission control pulse set, emit at least two additional first emission control pulse sets for a next two measurement points in the plurality of measurement points before emitting a next second emission control pulse set, each of the at least two additional first emission control pulse sets at the reduced first energy level to detect objects within the first safety range.

An emission control method, where the method comprises:

• for each measurement point in a plurality of measurement points in a scan field:
• emitting a first emission control pulse set at a reduced first energy level to detect objects within a first safety range;
• responsive to not detecting an object within the first safety range with reflections of the first emission control pulse set, emitting a second emission control pulse set following the first emission control pulse set and at a reduced second energy level to detect objects within a second safety range, where the second safety range is greater than the first safety range, and where the reduced second energy level is greater than first energy level, otherwise proceeding to a next measurement point in the plurality of measurement points in the scan field;
• and
• responsive to not detecting an object within the first safety range with reflections of the first emission control pulse set and to not detecting an object within the second safety range with reflections of the second emission control pulse set, emitting a ranging pulse set at a higher energy level where the higher energy level is greater than the reduced first energy level and the reduced second energy level, then proceeding to the next measurement point in the plurality of measurement points in the scan field.