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ArcticMyst Security by Avery

StarWarz CO2 Power

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Take note though the beam will be smaller with a shorter focal length lens than it would be with a longer one.
 





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LRO -1.39 FL optic followed by a 5" or 7.5" FL converging lens.

HMike

Hi Mike, I cant work out what "LRO -1.39 FL optic" is refering too, a 1.39 focal length lens? Does that mean if the lense was flipped it would be 1.39" FL"?

I'm interested in extending the burning ability of the CO2 laser. I have a CO2 tube mounted in PVC, definately not as pretty or as compact as yours but I left a 2" female fitting for a lens setup. I have ordered via eday a 1.5" dia 5" focal length lens, still uncertain what to put in front of it.

I've been playing with paint, wouldn't you be able to just use two focal lenses like the following (not to scale):

Edit: Just realised how far the lenses would have to be apart :p The less distance the better. So idealy the lenses would be as compact as possible and focusable from infinity to a few inches. Boggling my mind a bit.
 

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Aussi....
You are understanding it now !!!!! Super !!!!!

Hey this guy is comming up fast on optics using his drawings.

The LRO lens is a Laser Research Optics Negative (-) FL lens (Item L79051308-A0) 0.5" Dia @ -1.39" FL which shrinks the overall length of your expander by moving the FP behind the first (diverging) lens. Your optics will work but a -FL diverging lens shortens the mechanical length. Make your drawing with a -FL and you will see.....

HMike

oops --- The FP is behind the lens!!! It's an expander. Hard to grasp at first. Put the diverging lens behind the convex output lens.
 
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Hello Mike,
Very interesting RF laser! I am looking for a very simple pwm generator to run a Coherent RF laser I have. It is around 60w. I wondered if you might suggest a simple control for my project? Did you get all the beam expanders from Ebay?
 
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My PWM is based on a simple 555 circuit publish in IC literature. You will need to adjust the RC time constant components to your frequency range. I gathered the ZnSe lenses from ebay and elswhere when they could be found. ZnSe is a bit pricey but you can start close up with a 5 to 7" FL lens. Get an expander lens later. Try "Laser Research Optics" for a start.

HMike
 
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Mike you deleted your pictures?

I only just got my lenses in the mail yesterday, and actually only fired the laser itself up for the first time yesty as well. Its still a fair way from complete but : YouTube - Laser vs Modern Warfare 2

What I cant wrap my head around now is the relationship between the diverging anmd converging lenses, from memory yours was set in the right position with a PVC spacer and fixed, non adjustable was that right? Is it possible to focus it at certain ranges by varying the distance between the two lenses?

I now hold 0.75"dia -1" FP and 1.5" dia. +5" FP lenses.
 
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There are no pictures deleted here. I have posted this elswhere but the front lens can be moved to focus at different distances. Your small lens might work but I use a -FL diverging lens to shorten the assembly. All ZnSe optics.

1944-co2-8.jpg


HMike
 
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There are no pictures deleted here. I have posted this elswhere but the front lens can be moved to focus at different distances. Your small lens might work but I use a -FL diverging lens to shorten the assembly. All ZnSe optics.

1944-co2-8.jpg


HMike

Thanks Mike, it looks telescopic? funny none of your other pics are showing up for me now.

Yes I meant I have an expanding lens as well, -1" and a +5", pitty I have no machining ability to mount them.
 
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Auss ------
My last post to you got thrown away by the forum -- I'll try to create it again--------------

You now understand --- a beam expander IS a telescope !!! I use a -FL expander to shorten the assembly but a +/+ will work. You need to graph the beam paths on paper to see it.
I use PVC plumbing pipe and fittings but you might ba able to adapt an old telescope to do the job. I would start with a simple converging lens to observe the beam characteristics at close range.
Please be careful.

HMike
 
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I can see you are having fun with the co2 lasers I sold a while back. FWIW The 27mhz source can be swapped out for a CB radio and analog modulated; key full on, with various PWM signals to the mic input to adjust power. I wish people would actually appreciate the posts i make about how to do difficult things like get mm diodes to make a beam, revive old argon lasers, tune in these co2 lasers, and stop attacking me on this site.
 
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Chris --- The two ArIon lasers I got from you still work. The RF CO2 lasers work. Sooo many toys and so little time. Some of the "junk" you sent has become useful once I figured out what it is!
Sometimes your explanations are above me and many here to understand. Maybe a picture would help.
Also, you have somehow gotten enemys here and they Never forget.

HMike

Just a thought --- A basic 5 Watt CB radio won't light up one of these CO2 tubes unless it has the final amp on the tube housing and impedance matching will be needed understanding.
 
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HIMNL9

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^ a CB antenna matcher can help in impedance matching and ROS reduction (and they are relatively cheap, too) ;)
 
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I think my RF CO2 drives the tube with about 280 Watts of RF. Don't touch that copper strip "antenna" when it's on.

HMike
 

Arayan

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Mike you deleted your pictures?

I only just got my lenses in the mail yesterday, and actually only fired the laser itself up for the first time yesty as well. Its still a fair way from complete but : YouTube - Laser vs Modern Warfare 2

What I cant wrap my head around now is the relationship between the diverging anmd converging lenses, from memory yours was set in the right position with a PVC spacer and fixed, non adjustable was that right? Is it possible to focus it at certain ranges by varying the distance between the two lenses?

I now hold 0.75"dia -1" FP and 1.5" dia. +5" FP lenses.

Nice CO2 laser :)...what are the specifications?
 
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Nice CO2 laser :)...what are the specifications?

Apologies for the slow reply, its just a 60W ebay laser tube. Power supply, water tank, pump and radiator are mounted in wooden box under it. Not finished, i'll stick it on a pintle mount just for fun, and hopefully get these lenses fitted.
 




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