The "optical" microphone - a break through?

I was reading about the optical microphone. The idea is to eliminate any "burden" from the diaphragm of a microphone, like i.e. a coil it has to move or electrostatic forces on the metal plate. These "burdens" are diminishing the microphones abilities to strictly follow the airwaves and hence deteriorating the sound. The optical microphone now is using light to detect the movement of the diaphragm plus a Michelson interferometer to "perceive" the sound. Sounds interesting to me! Has anybody seen or heared such a biest?

it's an interesting idea - apparently spy agencies can detect sound bouncing off a window with a laser using the same principle - but you'll still have resonances built into your diaphragm and mic housing. also, it'd be crazy expensive. edit: also, you can already get really flat microphones - and they're not that useful as recording mics. but it's still a very cool idea.

One of the main benefits stephen paul mentioned about certain types of optical mics, that is of great interest to me, is the isolation possibility Imagine pointing at a tom right under a cymbbal!

Yeah, I'm thinking the technology could be used to amp double bass, or other instrument of the same nature where the non-magnetic property of the strings prohibit the use of regular pups.