A recent study conducted by researchers at the Ben-Gurion University of the Negev and the Weizmann Institute of Science in Israel suggests that hackers can now listen to your conversations from 25 meters away using a light bulb.

The near science fictional method is dubbed Lamphone and requires a remote electro-optical sensor that analyzes the changes in the light bulb’s frequency response to sound waves. The optical sensor can be focused on a light bulb using a telescope

The electro-optical sensor analyzes the subtle vibrations on the surface of the light bulb that is run through specially developed algorithms to isolate an audio signal from an optical signal. The output can be then passed through a voice-to-text application like Google Speech to translate it. Moreover, the range of Lamphone primarily depends on the telescope used.

Hackers Can Now Spy On You Using Light BulbsThe study details, “Lamphone recovers sound optically via an electro-optical sensor which is directed at a hanging bulb.” However, for accurate transcription, the bulb should be hanging from the ceiling and should be in the clear vision of the sensor.

The researchers claim that this process works equally well with singing. Applications like Shazam and SoundHound were able to recognize songs being played from as far as 25 meters using the method.