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ArcticMyst Security by Avery

what is the purpose

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Jun 25, 2011
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of a dichro mounted so that it can only reflect? i bought one of meridith lens 10 pc. sets a while back. it included cylindrical lens and some dichros, along with some other lens. one of the dichros is mounted so that i could shine a beam through it and reflect off of it. but there are two mounted so that they could only be used to reflect. why would one need this when a mirror would do just as well?
 
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ARG

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Dichros can be used as mirrors as they have a lower power loss when reflecting than broadband FS mirrors.

I find that most broadband mirrors are 80-95% reflection and dichros are usually 95% or higher (when at the ideal wavelength)
This usually isn't a problem but when working with high power systems losing 10% of the power is a significant loss.
 
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What he said. Dicroic mirrors can get damn near 100% reflectivity, and are required for low gain systems - HeNe for example.
 
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If the incident beam will always fall within such a narrow bandwidth for the specified optic, its better to optimize that chunk of glass for that narrow bandwidth - getting better performing, while not having to worry about its performance elsewhere on the spectrum.

Broadband FS mirrors serve their purpose well, but only generally. Not very specifically.

In our lab, the only optics we use for bounce mirrors on a 532nm YAG are dichros made specifically for 532nm YAG with pulse peak powers averaging out in the multi-kW range.

After repeated kW peak pulses incident on the same cm^2 of area on a 85% efficient optic, the metal IE mirror layer would heat very quickly and eventually warp and distort the wavefront.
 
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thanks so much for the answer. i was going thru my stuff, looking to combine beams and realized i didn't know just what they were for.:beer:
 




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