Photointerrupter / Photo Micro Sensor

Type: Optical Interrupter Switch

Function: Detects presence/absence of object via light beam interruption.

Components: LED (light emitter) + Phototransistor/Photodiode (receiver) in U-shaped housing.

Output Types: Digital (open collector or push-pull).

Applications: Encoder, paper detection (printers), position sensing, limit switches.

Key Parameters:

• Operating Voltage: 3.3V – 5V typical
• Detector Type: NPN/PNP phototransistor
• Response Time: ~2–10 µs
• Slot Width: e.g., 3mm, 5mm (for through-beam)

Circuit Tip: Add pull-up resistor (e.g., 10kΩ) on output if open-collector.