[time-nuts] Vibration isolation of quartz oscillators

[Poul-Henning Kamp]

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ed breya writes:

> The nicest optical bench I've ever seen in person, was in one of our 
> labs many years ago. It was a huge, precisely flat polished granite slab 
> about 6-8" thick, about 4x8' or maybe 5x10', mounted on active-leveling 
> pneumatic bladders. It was loaded with thousands of threaded inserts, 
> uniformly spaced on a grid, for mounting optical devices and equipment.

It is worth foot-noting here, that at that level of quality they
are usually not made from natural granite, but rather from
"epoxy-granite", which can be designed to have very low temp-co.

> There are lower-grade type platforms available, commonly called "optical 
> breadboards," that are made from thick sheets of aluminum or stainless 
> steel, [...]

and these obviously have a sizeable temp-co, so the money you saved on
your bench you get to spend on your air-con.

They are a lot easier to move around though.


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