What if hackers can spy and record your conversation without a digital device? What if your conversations could be retrieved by a simple, dumb bygone old-fashioned light bulb? Well, it might so be true.
Researchers from the Ben-Gurion University of the Negev and the Weizmann Institute of Science in Israel have been researching on sound waves as a means for eves dropping by studying the effect of these waves on objects and they successfully discovered a method of retrieving conversations through a simple light bulb from as far as 25 meters.
When we think of a privacy breach, it tends to come from android devices or hacked accounts or in some cases devices like Alexa or Google Home or Siri but these researchers don’t even need to plant a device much than implant a malware. They just need a clear vision of a bulb from less than 25 meters, bizarre isn’t it?
They called this method “Lamphone” – a side-channel attack for eavesdropping sound. But there are some major limitations; first, the need of a clear view of the bulb, if the bulb is even slightly obscured by a curtain or a lampshade- the method won’t work then the light bulb concerned should meet the requirements in the aspect of the thickness of glass or output of light and lastly, the quality of the sounds picked up will depend on the proximity of people to the bulb and loudness of their conversation.
How does it work?
Even with its drawbacks, there’s no doubt Lamphone is a genius method for spying conversations from afar. The researchers say they analyze the bulb’s frequency reaction to sound via a remote electro-optical sensor. The electro-optical sensor is attached to a telescope that views the bulb. The sensor picks up the vibrations on the surface of the bulb that occurred by changes in air pressure caused by the sound waves, an analog to digital converter converts the electrical signals to digital.
“We analyze a hanging bulb’s response to sound via an electro-optical sensor and learn how to isolate the audio signal from the optical signal. Based on our analysis, we develop an algorithm to recover sound from the optical measurements obtained from the vibrations of a light bulb and captured by the electro-optical sensor”, writes the researchers.
Lamphone can be used to recover human speech (can be identified by Google Cloud Speech API) and singing (can be identified by Shazam and SoundHound).