Researchers have developed SweepLED, a $7 LED attachment for smartphones that detects hidden camera lenses with 94% accuracy in under five seconds. The device is designed to locate concealed cameras embedded in everyday objects like chargers, desk clocks, and remote controls that could be used for illegal recordings.
The technology works by analyzing light reflection patterns. The smartphone camera remains stationary while the LED's light direction changes continuously, capturing how reflections move and distort across object surfaces. This method allows the device to distinguish camera lenses from other reflective surfaces on common items.