[Laser] New "laser" pages available for perusal.

[Chris L]

Thanks so much for your compliments, Barry!

The best lens that we've struck, so far, at a low price and with a good 
compromise between large aperture and absolute unwieldy dimensions is the 
type #F550 from 3Dlens.com in Taiwan which sells  for USA$28. It's 32 cm 
wide, 40 cm tall, focal length 55 cm, about f1.3. VERY fine groove structure 
and a superb image - BUT the company has packed our last order of 6 
inadequately as a result of which we received fouyr of the six damaged. Only 
corner damage, not fatal, but annoying. I hope they'll replace them for us - 
WE SHALL SEE!

Refer this web page (the bottom thereof) for lens details:

http://www.3dlens.com/enter.html?target=Large_Fresnel_Lens.html

All of the American suppliers (eg Edmund Scientific) charge much higher 
prices and freight.

Hope this helps - if you find any errors of logic, fact or typography in our 
family of web pages I'd very much like to hear about it. Our seemingly 
anti-laser stance has got a few 'noses out of joint' it seems - those who 
spend copiously on such things don't want to hear what we have to say on the 
subject. Che sera!

Best wishes,

Chris Long (not all of my audio clips are up yet - I'm slowly digitising 
lots of my old open reel tape logs back to 1970 in mp3 format, but mp3 does 
not like to compress audio with very poor s/n ratio, as I find. It tends to 
go 'swishy' if you know what I mean.

<BLOCKQUOTE style='PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #A0C6E5 
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style='FONT-SIZE:11px;FONT-FAMILY:tahoma,sans-serif'><hr color=#A0C6E5 
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From:  <i>&quot;Prof Barry Chambers&quot; 
&lt;B.Chambers at sheffield.ac.uk&gt;</i><br>Reply-To:  <i>Free Space LASER 
Communications &lt;laser at mailman.qth.net&gt;</i><br>To:  <i>Free Space LASER 
Communications &lt;laser at mailman.qth.net&gt;</i><br>Subject:  <i>Re: [Laser] 
New &quot;laser&quot; pages available for perusal.</i><br>Date:  <i>Sun, 21 
Aug 2005 16:27:21 +0100</i><br>&gt;Chris<br>&gt;<br>&gt;The new web pages 
are excellent - many thanks for all your efforts.<br>&gt;<br>&gt;Do you have 
any recommendations as to the best &quot;official&quot; 
Luxeon<br>&gt;collimating lens to use with the new Lumiled 3 
stars?<br>&gt;<br>&gt;73<br>&gt;<br>&gt;Barry<br>&gt;<br>&gt;<br>&gt;________________________________________________<br>&gt;<br>&gt;Professor 
Barry Chambers<br>&gt;Communications and Radar Group<br>&gt;Department of 
Electronic &amp; Electrical Engineering<br>&gt;University of 
Sheffield<br>&gt;Mappin Street<br>&gt;Sheffield<br>&gt;S1 3JD, 
U.K.<br>&gt;<br>&gt;phone:        +44 (0)114 222 5588<br>&gt;fax:            
   +44 (0)114 222 5834<br>&gt;<br>&gt;e mail:            
b.chambers at sheffield.ac.uk<br>&gt;WWW URL:   
http://www.shef.ac.uk/~el1bc<br>&gt;<br>&gt;_______________________________________________<br>&gt;Laser 
mailing 
list<br>&gt;Laser at mailman.qth.net<br>&gt;http://mailman.qth.net/mailman/listinfo/laser<br></font></BLOCKQUOTE>