Re: Resonant mirror noise

Posted by Michael Giacomelli on
URL: http://confocal-microscopy-list.275.s1.nabble.com/Resonant-mirror-noise-tp7588458p7588459.html

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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]>
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