Researchers have developed a side-channel attacking technique that can be applied by eavesdroppers to recover full sound from a victim’s room that contains an overhead hanging bulb. The technique for long-distance eavesdropping, called “Lamphone,” works by capturing minuscule sound waves optically through an electro-optical sensor directed at the bulb and using it to recover speech and recognize music. The researchers recovered an audible extract of President Donald Trump’s speech that could be transcribed by Google’s Speech to Text API.
Source: https://thehackernews.com/2020/06/lamphone-light-bulb-spy.html