Dell 3010CN Service Manual page 48

Chapter 2 Operation of Diag.
-About Sensor
The sensors in the printer are reflective type and transmissive type.
A reflective sensor detects, on the basis of whether or not the light is reflected by the sheet, the
paper absence/presence or the sheet type such as OHP transparency or others.
Transparency Paper
Leg_Sec02_015FA
A transmissive sensor is composed of the light-emitting side and the light-receiving side that are
placed opposed to each other allowing the light to pass from the former to the latter. On the basis
of whether or not the light path is blocked due to the actuator, etc., the sensor detects the paper
absence/presence or the moving part position such as at the home position or elsewhere.
Actuator
Leg_Sec02_016FA
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