How to Use foto_interruptor: Examples, Pinouts, and Specs

The KY-010 Photo Interrupter, manufactured by ESP32, is an optoelectronic device designed to detect the presence or absence of an object by interrupting a beam of light. It consists of an infrared LED and a phototransistor housed in a U-shaped structure. When an object passes through the gap, it blocks the light beam, causing a change in the output signal.

This component is widely used in applications such as:

• Object detection in automation systems
• Rotary encoders for measuring rotational speed or position
• Line-following robots
• Limit switches in 3D printers and CNC machines

The KY-010 Photo Interrupter is a compact and reliable device with the following specifications:

The KY-010 has three pins, as described in the table below:

1. Wiring the KY-010:

   • Connect the VCC pin to a 3.3V or 5V power source.
   • Connect the GND pin to the ground of your circuit.
   • Connect the Signal pin to a digital input pin on your microcontroller (e.g., Arduino UNO).

2. Circuit Example:

   • Place the KY-010 in a position where an object can pass through its gap to interrupt the light beam.
   • Use a pull-up resistor (e.g., 10kΩ) on the Signal pin if necessary to ensure a stable HIGH signal when the beam is not interrupted.

3. Arduino UNO Example Code: Below is an example code snippet to read the KY-010's output using an Arduino UNO:

   // Define the pin connected to the KY-010 Signal pin
   const int photoInterrupterPin = 2;
   
   void setup() {
     pinMode(photoInterrupterPin, INPUT); // Set the pin as input
     Serial.begin(9600); // Initialize serial communication for debugging
   }
   
   void loop() {
     int sensorState = digitalRead(photoInterrupterPin); // Read the sensor state
   
     if (sensorState == LOW) {
       // The light beam is interrupted
       Serial.println("Object detected!");
     } else {
       // The light beam is not interrupted
       Serial.println("No object detected.");
     }
   
     delay(100); // Add a small delay to avoid spamming the serial monitor
   }
   

• Ensure the gap of the KY-010 is free from dust or debris, as this can affect its performance.
• Avoid exposing the KY-010 to direct sunlight or strong ambient light, as this may interfere with the infrared beam.
• Use a pull-up resistor if the output signal is unstable or noisy.
• When using the KY-010 in high-speed applications (e.g., rotary encoders), ensure your microcontroller can handle the required sampling rate.

1. The KY-010 does not detect objects:

   • Solution: Check the wiring and ensure the VCC and GND pins are properly connected.
   • Solution: Verify that the object passing through the gap is opaque enough to block the infrared beam.

2. Unstable or noisy output signal:

   • Solution: Add a pull-up resistor (e.g., 10kΩ) to the Signal pin.
   • Solution: Ensure the KY-010 is not exposed to strong ambient light or infrared interference.

3. False detections or missed objects:

   • Solution: Ensure the object is moving at a speed that allows the KY-010 to detect it reliably.
   • Solution: Check for any obstructions or misalignment in the sensor's gap.

Q: Can the KY-010 be used with a 3.3V microcontroller like the ESP32?
A: Yes, the KY-010 is compatible with both 3.3V and 5V systems, making it suitable for use with the ESP32.

Q: What is the maximum object thickness the KY-010 can detect?
A: The KY-010 has a gap width of 5mm, so it can detect objects up to approximately 4.5mm thick.

Q: Can the KY-010 detect transparent objects?
A: Transparent objects may not block enough infrared light to trigger the sensor. For such applications, consider using a different type of sensor.

Q: How can I increase the detection range of the KY-010?
A: The detection range is fixed by the gap width and the sensitivity of the phototransistor. For larger detection ranges, consider using a reflective optical sensor instead.

By following this documentation, you can effectively integrate the KY-010 Photo Interrupter into your projects and troubleshoot any issues that arise.