Why do TV remotes still use infrared instead of Bluetooth?

Say it out loud and you’ll feel like the hero of an old spy thriller: Infrared. Or maybe it’s just us. Either way, infrared (IR) now seems like an antiquated technology, a relic of a bygone era. In the age of Bluetooth and high-bandwidth Wi-Fi, it seems like infrared should have been phased out a long time ago, but a number of manufacturers are still using it in their newest high-resolution TVs and remote controls.

Infrared remote controls began to gain widespread adoption in the late 1970s and early 1980s, when they emerged to dethrone ultrasonic clickers (the very first wireless TV remotes, introduced in 1956 by Zenith Electronics). Infrared quickly became ubiquitous, appearing in controllers for everything from multi-disc CD changers to slide projectors and air conditioners.

So why is a technology that appeared in the 1970s still so widely used today? You probably won’t be surprised to learn that the reason is largely cost. That said, infrared also leads in terms of simplicity, reliability and energy efficiency compared to more modern wireless technologies.

Infrared works by transmitting codes in the form of infrared radiation (this is also how your Oura Ring reads your blood oxygen level, but without the codes). A microprocessor creates a binary code and instructs a remote control transmitter to encode it into pulses of light, which it sends to the device. A detector in the target device picks up the binary and translates it into commands, like Channel Down or Change Input.

IR is extremely cheap. All you need to integrate it into a remote control is a cheap LED transmitter and receiver. Manufacturers also don’t have to worry about paying dues and fees, as they do with Bluetooth, which is controlled by a consortium (the Bluetooth Special Interest Group). There’s that old saying, “If it ain’t broke, don’t fix it,” and infrared has been working and working well for over 40 years now. It’s simple: the remote control flashes, the detector counts the flashes. It also relies on line of sight, which reduces interference.

Then there’s the question of efficiency, a major consideration in the era of rising utility rates. IR uses less power than Bluetooth, and because the transmitter only activates for very brief intervals, the batteries tend to last a very long time.

That said, Bluetooth has become a dominant standard for a reason. Although it suffers from some common issues, it also offers common fixes. Plus, it’s everywhere, in almost every smartphone, and you can buy a dongle to add it to a PC for just $10. It allows a wide range of devices to convert data into radio signals and exchange them over the air. Although Bluetooth is usually found in things like smartphones or wireless speakers, it’s also increasingly showing up in remote controls, and for good reason.

For one thing, Bluetooth doesn’t require line of sight. Have you left the living room TV on and it’s blaring while you go to bed? Bluetooth has your back. It can reach across the wall between the two rooms and turn off the television without even requiring you to ruffle your blankets. It also has a much longer range. While infrared tends to reach around 10 meters, Bluetooth can reach up to ten times that distance. Bluetooth also lets you connect to multiple devices at the same time, while infrared is strictly individual with only the device the remote is programmed to control and point at.

Finally, there is the wide angle of compatibility. Some device manufacturers avoid dedicated remote controls altogether because they know that most consumers have a smartphone or tablet, which can control a device without a specialized transmitter; you just need your device to work with Bluetooth.