[geeks] Whee! Lightning strikes, AGAIN!

[gsm at mendelson.com]

On Tue, Jul 28, 2009 at 10:27:08AM -0400, Sandwich Maker wrote:
>back in the '80s i talked with a cow-orker who was working on fiber
>cable tv.  he said the best lasers he saw had a line width narrow
>enough [5nm comes to mind] to pack 100 channels into the fiber
>'window', but they had no control over the process variables that
>affected this, and for their purposes then it didn't matter.  it might
>be better now.  he also said that the lasers could be tuned in
>operation, by voltage iirc.  this makes me think that modulation would
>increase the space needed per channel.
>
>i don't recall if this was at 1.3 or 1.55 microns.  i have vague
>memories that they weren't very different.

I may be wrong, but lasers today are solid state which means that they
produce whatever color they produce due to their chemical composition.
I assume that over their life time there is some "drift", but you can't
tune them. 

Geoff.

-- 
Geoffrey S. Mendelson, Jerusalem, Israel gsm at mendelson.com  N3OWJ/4X1GM