This phone accessory spots hidden cameras in 5 seconds — SweepLED prototype uses LED reflections and could cost only $7

SweepLED can spot hidden cameras by varying its illumination AI can detect camera lenses by the light that gets reflected back The accessory fits on the back of a camera and works in seconds Unless you're in the safety of your own home, there's always a worry that you're being surveilled without your knowledge — when you're in an Airbnb, hotel room, changing room, or restroom, for example.

Now researchers have developed an LED-powered phone accessory to give you some extra peace of mind.

It's called SweepLED, and it's the invention of a team from the Korea Advanced Institute of Science and Technology (KAIST).

The portable device combines 15 LED lights, a cable to attach to your phone, and some AI processing.

According to the researchers, SweepLED can spot hidden cameras 94% of the time with a processing period of just five seconds per object.

While this is only a prototype for now, the team has tested it on 30 different objects, reporting a high level of skill at identifying where hidden cameras are embedded (or not).

Here's how it works: SweepLED fixes to the back of a phone (over the camera).

As video is recorded and the phone stays still, the add-on turns its LEDs on and off, comparing different reflection patterns against each other.

Hidden camera lenses show up in those reflection patterns in a way that standard reflective surfaces don't.

Protecting your privacy SweepLED uses reflection patterns to find cameras (Image credit: KAIST ) "Hidden cameras pose a serious threat to personal safety and privacy in everyday spaces," says Professor Jun Han , from the KAIST team.

"This research is meaningful in that it combines low-cost smartphone-based hardware with AI analysis to present the possibility of a practical detection technology that even non-experts can use." Previous devices along these lines required users to look for 'bright spots' manually as they were lit up by the detector, the tell-tale sign that there was a camera looking back at them.

This should be more efficient, and better at spotting different camera types hidden in a variety of different housings (like clocks or mirrors).

There's still plenty of work to do to get this refined and commercialized, but it shouldn't be expensive: the KAIST team reckons the manufacturing cost of SweepLED would be in the region of $7 (about £5 / AU$10).

If you do a lot of traveling, it might be worth investing in something like this just to make sure you're not being spied on.