IR remote and sensor

Other Hardware Sensors
3

Here's a link to one example. Remote keypad (which would be an emitter), in this case a receiver on the circuit board, and a separate LED.

http://www.ebay.com/itm/IR-Receiver-Module-Wireless-DIY-Kit-for-Arduino-Infrared-Remote-Control-Module-/182424655131?epid=1461375051&hash=item2a795b551b:g:5MIAAOSw~OdVb7ir