Paper Timing Sensor (Pts - Printronix L5000 Series Maintenance Manual

Paper timing sensor (PTS)

This sensor is also a photo–interrupter. However, because the output signal is used as
the cut–sheet leading–edge detection signal and affects printing quality, the
mechanical aspects (lever) have been eliminated.
The paper timing sensor consists of an LED light emitter and receptor on either side
of the transport path. When paper passes through this location, light between the light
emitter and receptor is blocked, causing detection of the leading edge of the paper.
Light receptor
Paper
D–14
Optional Cut Sheet Feeder