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ArcticMyst Security by Avery

Greens Can Indeed Burn

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^Yes, but only with low-powered greens (up to 100mW). The only differences between red and blu-ray, and IR for greens is the pinout (808nm IR LDs are case-positive) and current. Since pump diodes for green lasers are very powerful, they will typically (but not always) require more current than red and blu-ray diodes.
 





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The only differences between red and blu-ray, and IR for greens is the pinout (808nm IR LDs are case-positive) and current. Since pump diodes for green lasers are very powerful, they will typically (but not always) require more current than red and blu-ray diodes.

That is a good reason to use the #18650 battery like this laser design uses.

The Green lasers use about 4 times the power.

A #317 cicuit will drive 1 amp (about 150mw Green) with adequate heat sinking.

LarryDFW
 
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Very nice larry, PM me if you have any of these lenses, i am working towards this goal myself.

Dark
 
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Very nice larry, PM me if you have any of these lenses, i am working towards this goal myself.

Dark

Larry- If I may make a suggestion... (you may have already considered this) If you coat the lens for high transmission in green and make the band of transmitted wavelengths as small as possible, you can eliminate the need for an IR filter, as the lens itself would act as one (of course you may get a tiny bit of residual IR but it's really not a problem to begin with).

Also, aspherical may not be the way to go. The "raw" output from the crystals does not diverge nearly as much as the beam from a laser diode.
In order to achieve the results you see, the beam is expanded with a tiny concave lens placed directly above the crystals. This beam then passes into the final lens for collimation. In most cheap greens I have found that the "expander" lens is acrylic. If this lens is removed and a single element collimation lens is used you can get a small increase in power and a cleaner beam. If you plan on replacing both optics and getting decent divergence, you may have to use a 2 element lens to expand and then correct the beam.

Do you plan on putting these 532nm lenses into production?
If so, it may be difficult to produce a "one size fits all" lens for greens as there are many different types, and not all require the same focal length collimation lens.
 

c4r0

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Hey guys, I don't get the idea... Green laser can be collimated and focused by lens and if it's focused enough and has enough power it will burn things... isn't it obvious actually?
 
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c4r0;

Greater than 90% of green lasers only focus down to a parallel collimated beam.

You need to focus to a fine point for burning material.

That is what I was trying to demonstrate.

LarryDFW
 
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Larry- If I may make a suggestion... (you may have already considered this) If you coat the lens for high transmission in green and make the band of transmitted wavelengths as small as possible, you can eliminate the need for an IR filter, as the lens itself would act as one (of course you may get a tiny bit of residual IR but it's really not a problem to begin with).

Also, aspherical may not be the way to go. The "raw" output from the crystals does not diverge nearly as much as the beam from a laser diode.
In order to achieve the results you see, the beam is expanded with a tiny concave lens placed directly above the crystals. This beam then passes into the final lens for collimation. In most cheap greens I have found that the "expander" lens is acrylic. If this lens is removed and a single element collimation lens is used you can get a small increase in power and a cleaner beam. If you plan on replacing both optics and getting decent divergence, you may have to use a 2 element lens to expand and then correct the beam.

That is a good idea RA.

I have seen some "Greens" that do use the coating for reduction of the IR.

Since the passband of my standard lens assembly (like you have), is 400 to 600 nm, it should provide some rejection of IR. Outside the passband, it should be at least ~20% loss @ 1064nm.

This is one style of several new focusable Greens & Reds that use the Aixiz lens assembly.

Rayfoss Adjustable 150mw Green

These would allow a drop-in AR Hi-Power aspherical glass replacement for the final lens.

LarryDFW
 
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cul8r

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This lens added where did it come from and can they be had? If so from where and are there any other possible add-on lens combinations that help focus? Any other options of turning one lens systems into two lens systems with fine point focusing qualities?
 
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I have plenty of them. They are $10 prepaid. I'll send instructions on mounting them to the cover.

I am really trying to retrofit one of these Aspheric Hi-Power. short focal length single lenses that is in my signature in RED.

I am getting pretty close.

LarryDFW


This lens added where did it come from and can they be had? If so from where and are there any other possible add-on lens combinations that help focus? Any other options of turning one lens systems into two lens systems with fine point focusing qualities?
 
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c4r0

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c4r0;

Greater than 90% of green lasers only focus down to a collimated beam.

You need to focus to a fine point for burning material.

That is what I was trying to demonstrate.
Thanks for the answer, but I still dont get it. If the beam is well collimated you can ALWAYS focus it to fine point, in case of green lasers the point can be even smaller than with red lasers. So if any light can be collimated it can also be focused to fine point, that's what comes out of optics principles, I don't understand why green lasers would be different :|
 
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bryce007;

Rayfoss now has the 100mw model for $75.

FocalPrice still has the 50mw model For $37 prepaid.

50mW_Adjustable_Green_Laser

This laser does have decent glass lenses that can be adjusted further...
by removing the soft material fixing the lens shown in the 1st post.

I tried some different lenses on this laser tonight.

The 3-element glass lens worked well with it.

If I was buying a green laser, I would look at this style,
since it takes the 9mm lens assembly directly:

Rayfoss Green

Both adjustable Greens are nicely built lasers.

LarryDFW
 
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Thanks for the info. Yea that 150mw is awesome, however I don't have the money for it. How does that 50mw look at night? Good beam visibility?
 
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bryce007;

The 50 mw has a nice fairly-tight beam at night.

And with a slight lens mod, it can burn a little.

It's a good choice for $37.

LarryDFW
 
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One last question Larry (I think), did you have any problem with customs when ordering the 50mW green laser? Because I've heard that any hand held laser over 5mw could be taken by US customs.
 
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I have heard that many have arrived with no problem.

I have been able to adjust the beam on this model by freeing up the lens assembly.

LarryDFW
 




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