The part list consists of one Arduino, two resistors, and one IR emitter. That’s right, an emitter. When an LED (IR or otherwise) is reverse biased it can act as a light sensor.

The Arduino Uno Infrared Sensor Receiver Module detects infrared (IR) signals emitted by IR transmitters. It typically includes an IR receiver and a circuit to demodulate the received signals, ...

Photoelectric sensors detect objects and surface changes using variations in optical properties. Each sensor includes a light emitter and a receiver, with most relying on infrared light. In optical ...

DAOKI PCS IR Infrared Obstacle Avoidance Sensor Module for Arduino Smart Car Robot 3-Wire , KOOBOOK 2Pcs Digital 38KHz Infrared IR Receiver Sensor Module for Arduino Compatible , Photocell Sensor ...

Photocell Sensor for Gate Opener, Pair Universal Infrared Sensors 24v for Automatic Doors, Swing Gate, Sliding Gate (Include Transmitter and Receiver) KOOBOOK 2Pcs Digital 38KHz Infrared IR ...