KY-010 Photo Interrupter Module – Optical Slot Sensor for Arduino & ESP32

The KY-010 Photo Interrupter Module is a compact optical sensor designed to detect objects passing through a narrow slot using infrared light.

The module features an infrared emitter and phototransistor receiver positioned opposite each other. When an object interrupts the infrared beam, the sensor's output changes, allowing a microcontroller to detect movement, position, or object presence.

It is ideal for Arduino, ESP32, Raspberry Pi, robotics, motor speed measurement, rotary encoders, and automation projects.

Key Features

• Model: KY-010
• Sensor Type: Optical Photo Interrupter
• Detection Method: Infrared Beam Interruption
• Output Type: Digital
• Operating Voltage: Typically 3.3V–5V DC (Module Dependent)
• Sensor Configuration: Infrared LED and Phototransistor
• Non-Contact Object Detection
• Fast Response for Motion Detection
• 3-Pin Interface: Signal (S), VCC (+), GND (-)
• Compact PCB Design
• Suitable for Arduino and Microcontroller Projects

Technical Specifications

Pin Configuration

Arduino Connection Example

The Arduino monitors the digital output to determine whether an object is blocking the infrared beam.

Arduino Example Code

const int sensorPin = 3;

void setup() {
  pinMode(sensorPin, INPUT);
  Serial.begin(9600);
}

void loop() {
  int sensorState = digitalRead(sensorPin);

  if (sensorState == LOW) {
    Serial.println("Sensor LOW");
  } else {
    Serial.println("Sensor HIGH");
  }

  delay(100);
}

Note: The relationship between HIGH/LOW and beam-blocked/beam-clear states may vary depending on the module circuit. Test the actual module to determine its output behavior.

Applications

• Motor Speed and RPM Measurement
• Rotary Encoder Systems
• Object Detection and Counting
• Robotics and Automation
• Position Detection
• Wheel Rotation Monitoring
• Conveyor Belt Object Counting
• Arduino and ESP32 Projects
• Educational Electronics
• DIY Optical Switching Systems

Important Notes

• The KY-010 is a transmissive optical sensor, not a reflective infrared proximity sensor.
• Objects must pass through the sensor's slot to interrupt the infrared beam.
• The module cannot measure distance.
• For RPM measurement, use a rotating disk or wheel with slots or interruptions and count the output transitions.
• Detection performance depends on object size, alignment, and sensor characteristics.
• For ESP32 and Raspberry Pi, ensure the output voltage does not exceed 3.3V.
• Verify the operating voltage and output behavior of the supplied module before connecting it to a microcontroller.
• High-speed applications may require interrupt-based detection rather than continuous polling.

Package Includes

1 × KY-010 Photo Interrupter Module