Good to know, thanks.  I'm running these off a microcontroller with a=20
transistor driver, so I've got enough drive capability to put them in=20
parallel.

Curious -- if you're allowed to say -- what do these huge emitters=20
control?  Since you mention movie theater, are you broadcasting audio or=20
some other effects?

Cheers,
-Neil.



On 10/17/2016 3:07 PM, Harold Hallikainen wrote:
> We make an IR panel with about 100 LEDs in it. The LEDs are modulated wit=
h
> three RF carriers (1.8MHz FSK, 2.3MHz FM, and 2.8MHz FM). The IR panel is
> mounted on the back wall of a movie theater. The IR is reflected by the
> screen at the other end (up to 30 meters away) and covers the auditorium.
> We also allow for the use of slave panels. I suggest these be mounted at
> the same location and just be used to get more IR power or to increase th=
e
> radiation angle. I have had people put panels in the four corners of a
> room with coax between them. The delays in the coax result in the RF
> modulation cancelling in some locations in the room. I visited one theate=
r
> that had trouble getting coverage in the middle of the room with four
> panels. We put one at the back of the room and got rid of the problem.
>
> In your situation, I see no problem with multiple LEDs to spread the
> radiation angle. Further, since the modulating frequency is pretty low,
> distance between them should not have any effect. You may be able to just
> hang more LEDs in series (our panels have multiple series strings of LEDs
> with each string driven by a current source).
>
> Good luck!
>
> Harold
>
>
>

--=20
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