Beam Output Angle

[steve-o]

I know we've all seen this problem with diode lasers; --my Lasever has about a 2 degree difference in vertical output angle than my LaserWave. The LW looks right on, but the LE projects higher (the base-plate near field is only about 1-mm diff in height, but at 8 ft they're 1.5" diff. I'm going to have to make a solid aluminum (for heatsinking) angled shim. Anybody got any other ideas about how to solve this problem (other than bouncing off of 2 mirrors instead of 1?)
Thanx,
Steve

[carmangary]

Tilt the laser with a shim.

[buffo]

You can always mount all your lasers on threaded rods (floating tables) and then adjust the height and angle of each laser that way. It gives you maximum flexibility, but it's cumbersome.

I used the floating table layout in my projector, and it's worked very well for me. Things to keep in mind: 1) make the table large enough - 1 inch or more bigger in each dimension than the baseplate of the laser head - to help dissipate heat (only if heat is a problem with your laser). 2) leave enough room between the tables to get a small wrench in there to adjust the nuts below the tables on the threaded rods. 3) use #10 stainless rod or thicker, threaded at 32 threads per inch or more. You need the thick rod for stability, and the fine threads make adjustment easier.

Carmangary's shim idea will work too. Heat isn't really a big problem with lower power lasers, so the shim shouldn't affect the heat transfer much. Even with my floating table design, none of the tables ever get warm to the touch. The bitch is machining the shim to the exact thickness you need. (You could always stack a bunch of really thin shims until you get the alignment right...)

Adam

[Stuka]

I second the "floating table" idea - I know it solved a LOT of alignment problems I was having, especially when mixing different size laser heads!

A recommendation (which I had to convince myself the hardway):

On the plates that you actually use for the floating tables for each of your laser heads, make the holes for the threaded rods oversized enough to allow you some lateral adjustment of the plate. One you find the "sweet spot" for each of the plates, you can lock everything down with washers, lockwashers, and nuts (or locknuts).

My "noobie" recommendation for anyone that doesn't have their own machine shop in the garage is to go ahead an plan on using floating tables to begin with, and it will probably wind up saving a LOT of extra work in the long run! Floating tables allowed me to align the beams of my CNI laserheads with my dual Maxyz, AND work the alignment with my dichro mounts without any additional shims for any of the optics, other than a 1/4" thick mounting plate for the scanner block.

[steve-o]

Thanks Y'all,
I like the floating table idea, I'll see if I can get my buddy with the machine shop at work to fix me up. Then I'll owe him 1.. (we work on the 'barter' system ) I make electronic stuff for him.

[aijii]

only problem is you can't easily seal the optics from dust.....

if one of your lasers needs to be on an angle, another method (if you care about dust sealing) is to get a block of aluminum machined at the appropriate opposite angle to even out the beams. Use different height risers on your lasers and scanners to get them all the same height, with heat paste between the lasers and the base plate. Then mount a fan forced heatsink under the lot, which is vented externally. That way your optics are completely sealed off - no need to clean after every show..

[steve-o]

From Aijii:

get a block of aluminum machined at the appropriate opposite angle to even out the beams.

Its being done as we speak. The precision milling will be to a 4.25" long piece of 1/16" aluminum with an angle of 54 arc-minutes (less than 1 degree) -(calculated by a very smart fellow whom I mentioned above)
He dislikes metric, so we talk in degrees,minutes,seconds; not radians -heh-

[survey]

Now all of you Know what a usefull thing like this could be, don't you?

You can forget the stepper, and use manual tilt, but as steve-o makes

electronic things... maybe he can do a litle controller.

Now imagine if you have a pair or a trio of such a thing with XY tilt in your RGB projector, sounds like medialas color corrector?

All the best.

[steve-o]

An automatic motorized x-y tilt for a floating table? Whoo, thats an ambitious project...

[allthatwhichis]

How bout using compressed air like shocks or hydrolics, or maybe airbags... Instead of a dancing truck bed we can have dancing beam tables. Little playstation controller for you beam heights.

Actually, the automatic thing would be cool if you could get some really fine screws on them like on dichro mounts.