[Laser] Laser Digest, Vol 56, Issue 7

[Dieter Palme]

Hi Dex, you are right. In this distance of the CCR your pointer produces
a beam big enough to illuminate the hole CCR. Therefore all 3 mirrors
are in action in different ways and so you get 3 beams with different
phase relation and you see interferences between the 3 reflected beams.
73 de Dieter - dl7udp -

-----Ursprüngliche Nachricht-----
Von: laser-bounces at mailman.qth.net
[mailto:laser-bounces at mailman.qth.net] Im Auftrag von
laser-request at mailman.qth.net
Gesendet: Montag, 9. März 2009 17:00
An: laser at mailman.qth.net
Betreff: Laser Digest, Vol 56, Issue 7


Send Laser mailing list submissions to
	laser at mailman.qth.net

To subscribe or unsubscribe via the World Wide Web, visit
	http://mailman.qth.net/mailman/listinfo/laser
or, via email, send a message with subject or body 'help' to
	laser-request at mailman.qth.net

You can reach the person managing the list at
	laser-owner at mailman.qth.net

When replying, please edit your Subject line so it is more specific than
"Re: Contents of Laser digest..."


Today's Topics:

   1. Laser newbie conner cube reflection question
      (W4DEX Dexter McIntyre)


----------------------------------------------------------------------

Message: 1
Date: Sun, 08 Mar 2009 23:35:01 -0400
From: W4DEX Dexter McIntyre <dmcintyre at att.net>
Subject: [Laser] Laser newbie conner cube reflection question
To: Free Space LASER Communications <laser at mailman.qth.net>
Message-ID: <49B48E65.1040501 at att.net>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed

I now have a trihedral prism, conner cube or retroreflector (are there 
any more names for the device?)  Using a 5 mw green laser pen with the 
reflector set approximately 250 feet away I get an interesting 
reflection. The reflection is about an 8 CM diameter from the 4 CM 
diameter cube with very noticeable concentric circles.  I tried to 
photograph the display but was unable to get the exposure right to see 
the circles.

http://w4dex.com/laser/laser_250ft.jpg

I'm guessing this is created by phase cancellation but so far I haven't 
been able to confirm this with Google. 

Dex


 


------------------------------

_______________________________________________
Laser mailing list
Laser at mailman.qth.net http://mailman.qth.net/mailman/listinfo/laser


End of Laser Digest, Vol 56, Issue 7
************************************