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I'm looking for a filter that lets through as many wavelengths as possible (from 200 to 5000 nm).

Is that even possible?

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how is that different from no filter? a vacuum is pretty good at transmitting those wavelengths ;-) – Nic Dec 20 '11 at 13:13
I need something to close the tube in which the experiment will take place. And the filters that are going to close it must let as much light as possible. – Migelo Dec 20 '11 at 13:59
I have not heard of anybody making filters that have such a large bandwidth. – Antillar Maximus Dec 20 '11 at 14:35
They make them, but they don't call them filters; mainly because they don't filter! Those are called windows. – Colin K Apr 2 '12 at 17:32
up vote 4 down vote accepted

What you are looking for is usually called a window, not a filter. You need to check different manufacturers to choose a material that fits your requirements, including not only light transmission but also the pressure differential, chemical inertness, temperature range, etc. Checking ARS' website, calcium fluoride (CaF2) might be what you are looking for.

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Looks nice! I'll consult with team mates and report back! – Migelo Dec 20 '11 at 19:18
Ok, seems this is the think we are looking for. Thx! Now I just need to find it in Europe. – Migelo Dec 28 '11 at 21:11
My first choice would be CVI Melles-Griot. They make high quality optical components. – Colin K Apr 2 '12 at 17:34

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