IR Blaster

An IR blaster is a tiny infrared light, usually on the top edge of a phone or tablet. It sends the same kind of invisible light signals as a traditional remote control, so the device can act as a remote for appliances that use infrared.

How it works

Every button on an infrared remote sends a short code as quick flashes of light. The appliance has a sensor that reads the flashes and acts on the code. An app on the phone holds a library of codes for many appliance brands, or learns codes from an old remote, and the blaster flashes the right one when a button is pressed on screen.

Key points

• Infrared needs a fairly clear line between the blaster and the appliance's sensor. Walls and closed cabinets block it.
• The range is short, usually several metres.
• It only sends signals. It cannot read the status of the appliance.

What it does not promise

An IR blaster does not work with appliances that use Bluetooth or Wi-Fi for control, because those do not listen for infrared. It does not guarantee control of every infrared appliance either, since that depends on the app having the right codes. It is also separate from infrared parts used for other jobs, such as sensing a face.