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FrozenGate by Avery

Dragon Laser Beam Expander

I gave up on that too.. Ill have new one built in on my next blue laser.. for now I just tape a loop to the end of the spartan if i want to focus the beam and burn my signature into something :cryyy:
I'm having custom lasers built from another company..
 
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Greetings,

Personally I do not believe Dragonlasers will ever "perfect" their expander. Have been seeing and hearing almost ready for release the past few years.
It would be nice if some optics guru would create a real focus adapter and not just a beam expander. One with enough size to allow for focus to a pinpoint at almost any distance. From a few inches to a few hundred feet !!

Now that would be an adapter I would almost kill to have.....

Moe
 
I'm in the same boat. Was there anything wrong with the original to begin with? Was the original 22mm threads or did DR change to that?
 
Moe Ron said:
Greetings,

Personally I do not believe Dragonlasers will ever "perfect" their expander. Have been seeing and hearing almost ready for release the past few years.
It would be nice if some optics guru would create a real focus adapter and not just a beam expander. One with enough size to allow for focus to a pinpoint at almost any distance. From a few inches to a few hundred feet !!

Now that would be an adapter I would almost kill to have.....

Moe
Click to expand...

I don't believe that's practical.
Play with this app
gausian beam rev 2.0.xls
 
WOW, never thought I would see that show up.
Kind of confusing as it doesn't say if you need to buy both adapters (as in what does it come with). Shipping is expensive ($26 to N.Y.) for 8-15 days.
Just took a look at my Spartan and I never realized that the threads for the cap were the same as a standard lens.
 
I sold my spartan thinking this day would never come...... Dammit!
 
What is the relationship of expansion if you fed your beam into a 2X beam expander and then put another beam expander in front of that which was 10X? Does that equal 20X expansion? To me, this seems fairly straight forward and I'm thinking the expansion just directly multiplies, with losses, of course.

Curious what the maximum theoretical beam expansion possible is without loosing more than 50% of your power when using BK7 optics, anyone? What kind of setup is best for maximum expansion using no more than 2 lenses? 3 lenses? I've been googling on this subject for awhile now and there is lots of good information out there but so far, nothing found yet which gives me some ball park figures in regards to these kinds of questions. I'd like to see if a 50X or higher expander is possible, even if I have to put one beam expander in front of another and suffer the loss. The optics can get huge, I imagine... to go that high.

Edit: Of course, as soon as I post the question I finally find one of my answers on Google, yes, you can expand out much higher than 50X, I imagine, as high as you are willing to suffer the induced losses from optics if putting one expander in front of the other, giving enough aperature. Another question now, I wonder if anyone in this group has built an expander which can do a high ratio of expansion using relatively inexpensive optics, perhaps a telescope? I want to do so but for 808nm IR and at high power using a FAP unit which poses a problem, the input lens must be able to handle the size and heat of the input beam. At one time I had run across a youtube video where someone was pushing some power through a telescope to light a match over 100 feet away using a visible laser, can't find that video anymore but I believe it's still there.
 
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Laser Project said:
What is the relationship of expansion if you fed your beam into a 2X beam expander and then put another beam expander in front of that which was 10X? Does that equal 20X expansion?

At one time I had run across a youtube video where someone was pushing some power through a telescope to light a match over 100 feet away using a visible laser, can't find that video anymore but I believe it's still there.
Click to expand...

If I pick up one of the new expanders I'll try your idea.

And I found this video (he's a member here) lighting match from 82 feet


 
Wow. Sooo impressive. Do i have to say I want it? Well I want it.
 
My local surplus shoppe has a half dozen or so adjustable beam expanders. The scales are labeled 2-10x and they're coated for 1064nm. They're only $20 per so I'm interested enough that I plan on picking up 1 or 2 the next time I go there for some other bits-n-pieces but I was wondering if anyone here would know if the the 1064 coatings would work reasonably well for 532nm or whether I'd be wasting half of my photons. (PM me if you'd like me to snag one for you) Thanks!
 
I'm curious as well regarding coatings, wondering if the 1064 coating will pass 800nm without too much loss, well... no more than 10% loss is what I'd say is OK for what I want to do. I've seen some cheap Chinese expanders which are rated for both 1064 and 532, but not 800nm :(

I did some math today regarding expansion based on 1 mrad, from my numbers it seems a 1 mrad laser would expand out to 328 feet at 62 miles. Can someone check my math? I also find at 621 miles the beam would be .62 a mile wide, or over a half mile. You could cut the expansion down to 1/10th with a 10X expander, right? So that means at 62 miles your beam would be only 32.8 feet wide, that's a whole lot of light from even a 250 mw laser for that far away.

Added edit: If you do buy another beam expander, the input must be wider than your expanded beam to use it in series from another one, of course. I have no idea how much the wrong coating on the lens will attenuate your beam, if too far from the designed wavelength but I can imagine it could be quite lossy if too far.
 
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