New Mic Proof of Concept

United States Patent 7580533 issued on 25 August 2009 for a new type of microphone based on a laser-photocell pair used for detection of sound pressure waves in a stream of particles suspended in a stream of air. The stream could be synthetic smoke or fog.

This video shows one of the early bench top devices being demonstrated by David Schwartz of Schwartz Engineering & Design.

Category:

Science & Technology

Tags:

• David M Schwartz
• Smoke Mic
• Laser Accurate
• New Mic
• Smoke and Laser Mic

[AntiProtonBoy]

What kind of frequency response do you get out of this? A Bode plot of this thing would be interesting to see.

[imon2nd]

@AntiProtonBoy

Frequency response is reasonably flat out to 6K Hz, then falls. Changing physical parameters moved the response out to higher frequencies, but then we lost the low end. I think we can design a version of this that will be flat 20 to 20K. The big issue is dealing with the noise floor. We have to add DSP to handle that. I proposed an AES paper about the performance of the prototypes for the Fall 2010 conference . The paper was not accepted.

[evpdave]

Interesting microphone design, I hope it is a success for you. It reminds me a great deal of the research of Erland Babcock in the mid eighties, when he worked for Metasciences. I developed a massless microphone design in 2004, it uses heat generated by a flame. If interested search my vid for 'Optical Microphone Test by request'.

[imon2nd]

Thanks, Dave.

Babcock may be one of the patents I referenced.

I'll take a look at your videos and comment over there.

Best Regards,

David

[deezynar]

Great idea! Will you be able to reuse the smoke? If not, what will you do with the surplus?

Do you think you'll ever be able to make a handheld mic that uses this technology?

FYI, I saw the link to this video on GlobalSpec.

[imon2nd]

Thanks, Dee.

Yes, the smoke or fog can be recirculated.

Prototype 6, which we are working on now, will use water vapor, so we aren't concerned about reuse.

If we stay with water vapor and don't save the condensate, a handheld mic becomes very possible. Users might have to refill it with water every 100 hours or thereabouts.

Best Regards,

David

[a32Unitu]

The child experement ))) Watch mathpart of interferometry

[Derelictos]

i have an idea for a microphone how about we use a living tissue dog ear diaphram and the entire inner ear and pull the electron signals from that instead

[Derelictos]

i have an idea for a microphone how about we use a living tissue dog ear diaphram and the entire inner ear and pull the electron signals from that instead

[Derelictos]

reflect the laser off of a very light weight gold leaf diafram and then you will have more pronounced reflection movements

[deezynar]

Thanks, David,

I look forward to seeing your innovation enter the market. I'm sure it will become the new standard.