The quest for an ever higher accuracy in capture and playback of sound has reached a new peak. Traditional microphones contain on their inside some diaphragms, with characteristics that may influence both the microphone’s sensitivity and the quality of sound output.
The American scientist David Schwartz, inventor of the MP3 format, has introduced a new microphone which completely eliminates such interferences caused by the microphone’s inside components, simply by… eliminating the components themselves, and replacing them with a column of smoke and a laser beam.
The laser beam measures the deflections caused by sound in the direction of smoke, thus returning a very high fidelity sound. Since smoke is practically weightless, these deflections are almost exactly matching the shape of the sound wave that the microphone captures; therefore it will return a sound which is practically identical to the one coming from the source.
Furthermore, eliminating any mechanical parts is also enhancing the microphone’s level of sensitivity, allowing it to capture each single nuance of sound, as well as the slightest whisper. This makes the laser smoke microphone a potential breakthrough also in the audio surveillance field, where every single tiny sound can prove vital.
In this particular field, in fact, the first infrared microphone, developed in 1947, was used, which detected the vibrations of glass on a window caused by sound waves behind the window. This principle is still used by laser microphones, which can detect sounds through a window at a distance of up to 1500 meters.
Of course, the laser/smoke microphone is still in research phase and is only a prototype, but you can have an overview of its characteristics, in a demonstration presented by its inventor in the videos posted below.