>         I am looking for some IR LED's that have a flat face and
> produce a beam.
Well, the NARROW ones are still 5 degrees wide

>  I am trying to build a device that will let a person
> walk along a beam and track it with one of those IR modules that
> decode a 33-KHZ carrier.  A laser is overkill and would probably
> produce such a fine beam that it would be hard to find.
That depends on how wide you need.  You do the trig for your
application, but the track gets wide pretty quickly at 5 degrees.

For cost's sake, a lens might be the best way to get a narrow beam.
And if you're going to use a lens anyhow, then the standard 35
or so degree wide IR LED would work.

>  The IR LED's
> used in remote controls and similar devices are way too broad for this
> purpose.  What is the nomenclature or part number for such a LED and
> can I buy some from digikey or a similar supplier?

I just checked- no narrow beam lensed emitters in DigiKey Jul - Sept
1999 catalog, only the standard ones- 20, 35, or 40 degrees wide.

------------
Barry King, KA1NLH
Engineering Manager
NRG Systems "Measuring the Wind's Energy"
Hinesburg, Vermont, USA
www.nrgsystems.com