Xref: utzoo sci.electronics:14427 sci.physics:14370
Path: utzoo!attcan!uunet!cs.utexas.edu!asuvax!noao!ncar!mephisto!udel!berryh
From: berryh@udel.edu (John Berryhill)
Newsgroups: sci.electronics,sci.physics
Subject: Re: Lasers for communication
Message-ID: <30638@nigel.ee.udel.edu>
Date: 17 Sep 90 00:03:00 GMT
References: <153DAVE@ORION> <1990Sep13.020325.10622@nmt.edu> <7504@milton.u.washington.edu>
Sender: usenet@ee.udel.edu
Followup-To: sci.garbage
Organization: University of Delaware
Lines: 20
Nntp-Posting-Host: huey.udel.edu

In article <7504@milton.u.washington.edu> wiml@milton.u.washington.edu (William Lewis) writes:
>
>    I have a HeNe laser that I'd like to use for communication also. 

>My question is: how would I go about adding a modulator to the supply?

First off, these questions are better answered in the library than on
the net.

However, if you want to use your HeNe to transmit a signal, you are
going to be much better off modulating the light than its source.

In other words, let the HeNe stay on all the time and use something
in beam path that can either deflect the beam (an acousto-optic
modulator for instance) or vary its opacity (an LCD window with a
polarizer crossed wrt the LCD).

--
							      John Berryhill
					   143 King William, Newark DE 19711