Frustrated with IR repeaters that use RF links (like Terk)... ambient
>RF noise too high for reliable operation :-(
>
>It occurred to me that since I have a central "Great Room"
>architecture, that makes for a wide open optical shot across great
>expanses... as much as 60' per link... so a purely optical repeater
>should work nicely... pick-up the IR from a remote and blast an LED
>with an Ampere ;-)
>
>Ceiling heights of 12' to 16' and door openings of at least 8' means I
>don't have to contend with people getting in the way.
>
>So now I need pointers on how to collimate/focus an IR beam so it
>doesn't spread out too much at 60' range.
>
>Ideas?
>
> ...Jim Thompson
If you use say a TSAL6100, I doubt you would need a collimator for your application. The TSAL6100 is a narrow beam IR LED wavelength matched ( 940nm) to Vishay's and Panasonics IR detectors. I've used Panasonics PNA4602M and the TSAL6100 with no optics to 50ft but I've read of people who've far surpassed this. The tsal6100 has a high radiant intensity 1000 mW/sr at 1 amp pulsed current even considering
30% losses in side lobes for the price they are about the best bang for the buck ,particularly when you consider you wouldn't need optics.
TSAL6100 Data sheet
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PNA4602M
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Appnote on the basic's selecting suitable LED's
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If you find you do need to build a collimator
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You can use surplus optics and mirrors a list of dealers is here. Bottom of the page.
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Typically you would use a 40 to 60 degree emitter when using an optical system not a narrow one like described on the above page.