Re: IR radiation & Projectors

[P3D Gabriel Jacob <jacob@xxxxxxxxxxxxxx>]

>Another idea for the VM projector, since it uses mirrors to direct the
>light from one bulb to two paths, is to replace the common front 
>surface mirrors with "cold mirrors" (i.e. mirrors which absorb IR
>radiation and reflect light that will not heat damage the slides).
>These are available from Edmund.  Only problem:  Mirrors will get hot 
>and that's where you need a good fan.

That's a good idea but I think there shouldn't much of problem with the
mirrors getting hot since they reduce the IR radiation to the slides by 
transmitting the IR through them, thus the mirrors don't get hot. This 
is unlike heat absorbing glass that does get hot because it has to absorb
the IR and consequently increase in temperature. One thing though, even
if the mirrors don't get appreciably hot, of concern would be if any 
delicate components are behind the mirrors.

Gabriel


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