Process for reliably detecting the passage of a target object using a photoelectric control unit employing pseudo-random jitter factor pulses

摘要

A target acquisition system for a photoelectric control unit which helps avoid interference problems due to optical and electrical noise. The system provides for the interpulse interval between light pulses transmitted by the photoelectric control unit to be varied in accordance with pseudo-random jitter factors during the target acquisition process. Noise which may be on frequency with the normal repetition rate of the photoelectric control unit is then eliminated from the detection process pursuant to synchronous detection procedures.