Re: Resonant mirror noise

Posted by Power, Rory on
URL: http://confocal-microscopy-list.275.s1.nabble.com/Resonant-mirror-noise-tp7588458p7588460.html

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Hi Mike,

Thanks for your reply. I was rather referring to an 8 kHz fundamental oscillation. The noise is quite unpleasant - I’d hate to hear the 4 kHz if that’s worse as you say.

Isolation should be possible. Perhaps combined with some foam we’ll arrive at a workable system.

Yes, I assumed the same. Thanks again.

Regards

Rory

…………………………………………………………

Dr. Rory Power
HFSP Postdoctoral Fellow
Morgridge Institute for Research
Medical Engineering | Huisken Lab
330 N Orchard St, Madison, WI, 53715
Tel: [phone]
[hidden email]<mailto:[hidden email]>




On Jul 25, 2018, at 21:18, Michael Giacomelli <[hidden email]<mailto:[hidden email]>> wrote:

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Hi Rory,

8 KHz unidirectional or bidirectional (so 4 KHz fundamental)?  The 8 KHz
scanners are usually not that bad even at maximum amplitude because the 8
kHz tone is a lot harder to hear and essentially all the harmonics are out
of audible range.

For 4 KHz at larger deflection angles you either need hearing protection or
to really isolate it from the room.  A metal box around the scanner and a
window on the input port so that air cannot pass in/out of the scanner
helps a lot. This is how most commerical systems work.

I don't think the model matters; the noise comes from pushing air, so for a
given mirror size and deflection angle the noise power is going to be
almost constant.

Mike

On Wed, Jul 25, 2018 at 9:03 PM, Power, Rory <[hidden email]> wrote:

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Hi Confocalists,

We’re trying to circumvent the annoyance of resonant mirrors screaming at
8 kHz. I was wondering whether anyone has a recommendation for constructing
soundproof containment?

Generally were using inexpensive resonant mirrors from EOPC:
http://www.eopc.com/sc30.html

Also, does anyone know whether the more costly resonant scanners used for
confocal/multi-photon laser scanning microscopies are any better in this
regard? Were not hugely concerned with other attributes (simply for light
sheet microscopy stripe suppression) just the piercing noise.

Many thanks in advance!

Rory

…………………………………………………………

Dr. Rory Power
Morgridge Institute for Research
Medical Engineering | Huisken Lab
330 N Orchard St, Madison, WI, 53715
Tel: [phone]
[hidden email]<mailto:[hidden email]>