I recently had to build an infrared close proximity sensor that could tell if something was dropped in a parcel delivery drop box. ... Here is the diagram of my Arduino infrared close proximity sensor ...

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 serial communications is I2C and there’s a tiny optical sensor onboard along with an IR LED. Of course, you could send other keys than media controls. We wouldn’t mind going back and ...

The sensor is intended as an alternative to pyroelectric sensors or PIR detectors in home automation, building automation, healthcare, security and industrial applications. Typically human presence ...