Pololu 38 kHz IR Proximity Sensor - Fixed Gain, Low Brightness

/*Here's an example code in Arduino that reads the proximity from the Pololu 38 kHz IR Proximity Sensor - Fixed Gain, Low Brightness:
Note: This code assumes that the Pololu 38 kHz IR Proximity Sensor is connected to pin 2 of the Arduino board. If you're using a different pin, you'll need to modify the IR_PIN definition accordingly. The calibration factor of 8.9 was determined experimentally, so you may need to adjust it for your specific sensor. */

const int IR_PIN = 2;  // the pin connected to the IR sensor
unsigned long pulse_length;  // the duration of the IR pulse
float calibration_factor = 8.9;  // the calibration factor for the sensor

void setup() {
  Serial.begin(9600);

  pinMode(IR_PIN, INPUT);
}

void loop() {
  // wait for the sensor to detect an object
  while (digitalRead(IR_PIN) == LOW);

  // measure the duration of the IR pulse
  pulse_length = pulseIn(IR_PIN, HIGH);

  // calculate the distance to the object in centimeters
  float distance = pulse_length / calibration_factor;

  // print the distance to the object
  Serial.print("Distance: ");
  Serial.print(distance);
  Serial.println(" cm");

  // delay before reading from the sensor again
  delay(1000);
}