What a noob move.

Johnfp · Post by **Johnfp** » Wed Oct 12, 2011 6:46 am

I must be getting senile. I had the whole table set up, split beam H1. For some reason I decided to check polarization of the laser. (I already had the cover on and forgot to look at the brewsters.) For some reason I thought for making holograms on their side the tube lasers of this type were ok. Well, they are not. The are ok for overhead set ups. So I had to mount the laser on its side and re-set up the whole table. Not too bad, but what dumb nooby move...

Another day to settle.

Jeffrey Weil · Post by **Jeffrey Weil** » Wed Oct 12, 2011 7:54 am

Sounds like its time to buy a 1/2 wave plate.

Jeff W

BobH · Post by **BobH** » Wed Oct 12, 2011 9:13 am

Mounting lasers on their side isn't a good idea. They are made to cool properly with airflow going vertically through them. Much better for stability and lifetime to use creative orientation of beam steering mirrors to orient the polarization.

Johnfp · Post by **Johnfp** » Wed Oct 12, 2011 9:20 am

NOOOOOOOOOOOOOOOOOOOO!!!!

LOL!

Johnfp · Post by **Johnfp** » Wed Oct 12, 2011 11:21 am

Thanks Bob.

I thought these lasers were probably mounted in a weird position anyway, probably up and down for the scanner mounting. But I will take your advice.

Johnfp · Post by **Johnfp** » Wed Oct 12, 2011 11:33 am

Jeff, ima on a poor man's budget. I thought I had one, but it was a 1/4 wave.

142laser · Post by **142laser** » Thu Oct 13, 2011 11:13 am

Bob is right; if you are using the big Siemens laser it has vents on top for warm air to rise; it will be happier on it's feet; look on e bay for a 1/2 wave plate for HeNe. Phil

Joe Farina · Post by **Joe Farina** » Thu Oct 13, 2011 1:38 pm

Johnfp wrote:I thought I had one, but it was a 1/4 wave.

John, Anchor Optics has 1/2 wave film for $13 http://www.anchoroptics.com/catalog/pro ... &iid=22860 It works for me, but it needs to be tilted at a certain angle in relation to the input beam, for it to work well. I think there is more information on the site.

Jeffrey Weil · Post by **Jeffrey Weil** » Thu Oct 13, 2011 3:45 pm

Hello Johnfp,

You can rotate the polarization with a few mirrors like BobH suggested. There's a diagram somewhere here on the forum.

Jeff W

Johnfp · Post by **Johnfp** » Thu Oct 13, 2011 6:25 pm

You know, I'm no laser engineer but I would be those fins put on the top of the Simens laser is for sure cooling, but I bet they would be fine on the side. Actually, on the side, because they go from complete side to side would allow the heat to rise out the top part of the fin (laser is on its side) and give a nice pull of cool air at the bottom. The way it is flat, there is no pull in from bottom, I would imagine just a fight for hot air rising out and cool air trying to sweeze in , probably on sides which would be the coolest part.

Or. maybe I can just take the cover off.

Any...I told you so's before you tell me so?