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FrozenGate by Avery

6X Cylindrical pair test from group buy.

Hi Milos,

On OPT lasers ebay shop 2x are 445 and 520nm and 3x are 638nm.
I understand that with broadband coating they all can be used at 445nm, but do 3x look much different in curvature?
 





Thanks guys, but I already have a 2x and two 3x from OPT lasers. What is left for me to try is a 12x combination so I can rest my wandering brain and crank the power finally to max :-)

thanks
 
CX lens on 6x pair is slightly flatter in curvature so have longer focal length (CV is the same)...ie more distance between lenses is needed on 6x vs 4x pair while focusing to infinite
 
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What I like at OPT lasers is selling brass mount separately. Yes, for 25 dollars, but I do not have workshop, so have to look for what is available anywhere.

Is it right that they have discount for lpf mebers?

With 2nd mount put on top of lenses and scotch around it would look like cylindrical beam expander with no glue. Yes, I like glue, UV glue, superglue, but it can be difficult later to disassemble glued glass parts without damaging.

Question to specialists (sorry if I use wrong terms):
If 2 cylindricals are put on 2 different mounts moving along an optical rail with servo, could it be possible to make a "variable beam expander"? Or focus the beam in 1 dimension (at fast axis) at different distance? I suppose it should be enough with G-2 focused to infinity.
Then add rangefinder, processor (this is Red Cowboy's idea)...
 
Think about cyls just for beam shaping...this is one axis correction, so less diode 'astigmatism'.....in other words, better beam profile, more 'squared' spot rather then a line, so higher energy density, etc
Adjust cyls for infinite focusing, and fix distance between. This is cyl lens purpose...just to correct one axis, like anamorphic prism pair do, ie better beam profile, nothing else.

After that, you can go with a variable but Spherical lens beam expander (both axis) if you want focusing at several distances.
However, maybe you are happy with not cyl correction at all, if you can 'tolerate' such divergence and 'line' spots. In this case, you will have better beam profile with 3-elem colli, not g2
 
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RedCowboy said:
beamshapingbyRC_zpslovjvv7k.png
Click to expand...

This picture is misleading. The rays exit the divergent lens wrong way. The rays after the third focusing lens do not converge into a dot.

The cylindrical pair is a 1D Galilean telescope. Look for pictures of "Galilean telescope ray diagram"
 
3x following the 6x can be a 3 lens setup.
The 3x, and the 6x can be back to back, followed by properly distanced plano-convex lens. Ill try to finaly post pics of such tests in my thread tonight.
 
definitely. My guess is 12x will be best. I have tested 9x and 18x so far with varying results.
 
Hi Red Cowboy,

Jors have posted before in this thread that 3x and 6x sets can have same PCV lenses but only PCX lenses different in focal lengths.

This means that these numbers (2x, 3x or 6x) only have meaning for a given 2 lens set, but you can do a variable beam expander (6x, 12x or even more) with any of 3 lenses of any set if you know the focal lenths of these lenses and calculate the distanses between with the program lightmachinery Alaskan has posted before in Beam Expander Design Theory thread.
 
If anyone has a pair of 6x or 4x cylindrical lenses they want to get rid of, PM me, I got to snag a set of those.
 
I came across these beam expanders:
EFORCE LASERS
Found them after another Australian member pointed out that these guys sell hand helds in a lot of wavelengths. Looks like you have to con tact them for pricing on everything.
 
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