Theremin (yes, the same) invented a device using an infrared beam directed at windows which was able to capture speech from inside. [1] This is separate from his RF powered Thing bug that was installed in the US Embassy in Moscow. [2]

Similar techniques have been shown using lasers vibrometers to achieve a similar effect.

Both of these are perhaps not visual in the same way as this method in the article. But, do illustrate the long history of non-traditional microphone eavesdropping techniques.

[1]Albert Glinsky (2000). Theremin: Ether Music and Espionage. University of Illinois Press. p. 10. ISBN 9780252025822. Retrieved 2013-12-28. theremin family huguenot.

[2]https://en.wikipedia.org/wiki/The_Thing_(listening_device)