IR

Infrared (IR) signaling is a common method of remotely controlling consumer electronic devices. IR remote controls contain one or more infrared LED's that flash is a specific pattern, depending on the button pressed. The light beam can be detected up to 100 feet away, and decoded to operate the selected function. IR requires a direct line-of-sight between the remote control LED and the controlled device's IR receiver.

However, separate IR receivers can be located in a more convenient location to pick up the signal, and transmit it to another IR LED ("emitter", "blaster", or "flasher") that is located near the controlled device's IR receiver (or "eye"). Some devices can also store a sequence of commands for several different devices (called "macros"), and play them back from a single button press.

IR is usually a one-way communication from the remote control to the controlled device, so any feedback or confirmation usually relies on the user's ability to directly see or hear the result. This is acceptable for simple control, but creates difficulties in controlling complex systems. For this reason, more complex systems generally use either RS-232 or IP control, allowing them to confirm proper operation.