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Most powerful green handheld?

brendon7358

brendon7358

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With the new 1W 520nm diodes, I was wondering: What currently the worlds most powerful green handheld? Because I just ordered a 1.75W 520nm from a member here on the forums (very efficient diode :yh:), and that would be great if I had the worlds most powerful green laser when it arrived :D
 
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Yes I think that's as powerful as your going to get unless a new diode comes along. I haven't seen anyone claim more power yet. The only way to get more right now would be to build one that combines 2 beams and they are expensive enough with one.

Alan
 
Only two things about 520nm diodes vs 532nm DPSS, the 520nm has about 20% less perceived brightness to the human eye compared to 532nm. Also, their divergence is higher, so much higher they really need at least a 3X beam expander to get it to be close to a good 532nm DPSS laser but then the beam won't be as thin.

Edit: Oh, I had to come back and add a third; all of the 520nm lasers I've seen have a rectangle output, needing beam correcting optics to become more rounded, if you care about that.

All of these drawbacks can be overcome with more power and optics, except the fatter beam. For myself I like a fat beam with reduced divergence, tonight I took my 800mw JetLaser pointer with a 10X beam expander on it and added a large concave lens in front of that, to expand the beam even further. In one hand I had the pointer, in another a 12 inch diameter PCX lens, holding them about 2.5 feet apart (to be at the FL of the large lens) and shot into the night sky, it was awesome. My beam was expanded from 2mm to about 300mm, the light looked like a very tight cone extending out to the far mountaintops.

With a normal laser beam, due to being so thin, you cannot see the beam extend out in a cone-like shape which gets smaller and smaller as it travels away, quite the thing to see. With that much expansion, more than 150X, the beam expands very little for many, many miles. Through beam expansion, the divergence is calculated to be reduced from 1.5 to about .01 mRad or less, expanding from 12 inches diameter to 18 inches ten miles away, 75 inches 100 miles away. Without beam expansion at my lasers normal 1.5 mRad divergence, the diameter would be closer to 80 feet ten miles away, instead of 18 inches. I am assuming 1.5 mRad divergence with my laser, it may actually be a bit more.

To get back on your project, I'd add a beam expander to your pointer, I think you will like 10X, the beam then spreads ten times less over a given distance.
 
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The 3 element lens fixed that? Edit (as usual): I have a PL520 diode in a DTR module and when focused to a tight spot, I can't see the rectangle shape of the beam, but at a long distance, it becomes apparent. I used a G2 lens instead of three element lens, from what I now understand, 3 element lenses are superior to a G2 in regard to reduced divergence and better beam shape, even if they have more initial loss compared to a G2, you get more power at distance. Concur? Seems like I need to get some 3 element lenses then.
 
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I read through your thread too fast then, I would have never thought the acrylic lens would be so much better.
 
I wouldn't have thought so either but it is. I suggest you get some of all 3 types of lens and try them, you can get different results with different diodes, for example the ones with rectangular beams will give you bat wings splash when using a 3 element although yes it will give you a smaller dot at a longer distance. Just so any noobs reading this know, don't use an acrylic lens in anything class 4 (>500mW) or you may eventually melt it, the lens barrel is normally plastic. We have thread jacked Brendon's thread. +rep Brendon for buying what might be the most powerful green hand held. Pictures please when you get it.

Alan
 
I agree, thank you for the suggestion. I want to see photo's of his project when he is done too, I've been wanting to build one of those myself but keep putting money into DPSS 532nm :p
 
Hmmm that sounds weird. I recently purchased a 1.5W 520nm module from DTR and threw it in one of Sinners hosts (haven't posted anything yet). Purchased it the same way I always do with the G-2 as it is cheaper to gain another G-2 buying it as a complete module and then tossing in a 3-element. In fact I should be getting another 4 405 3-elements from him today to change the rest of them. I've no intention of selling my G-2's;)
The 3-element makes the dot pretty nice and I find it surprising that yours was not good with it. The G-2 looked terrible as expected.
Just realized we are talking 2 different diodes as I couldn't understand how you were not burning up your acrylic lens.
Mine peaks just over 1.5W at 2.4A and I think from DTR's testing this is highly likely. Haven't done any testing past maybe 10 seconds as I noticed someone else did the same thing mine did which is peak just over and then drop to a bit above 1.4W.
I have no intention of upping the output but what is the driver set at for the 1.75W? My strongest 532nm is just over .6W and I currently have no intentions of getting anything with more output as I greatly prefer the 520nm color.
That 1.75W is the strongest one I've heard of so far.
 
1.75W from a 520 diode is the highest I have heard as well. sounds unlikely, but even if it is really efficient, it's probably also driver really hard. if it is a really good diode, I'd run it at a little lower current to try and lengthen its life. 1.25W- 1.5W would be plenty bright enough for me. mine does about 950mW but It is run at it's rated current of 1.7A and does not use a single element lens, hence the <1W output. still, close enough for me and my diode should last. just a thought, $390 is more than I'd want to spend on a diode replacement, but you may get lucky or use them very infrequently.

please post pics:lasergun:
 
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Shakenawake said:
1.75W from a 520 diode is the highest I have heard as well. sounds unlikely, but even if it is really efficient, it's probably also driver really hard. if it is a really good diode, I'd run it at a little lower current to try and lengthen its life. 1.25W- 1.5W would be plenty bright enough for me. mine does about 950mW but It is run at it's rated current of 1.7A and does not use a single element lens, hence the <1W output. still, close enough for me and my diode should last. just a thought, $390 is more than I'd want to spend on a diode replacement, but you may get lucky or use them very infrequently.

please post pics:lasergun:
Click to expand...

I pm'd the seller asking what it is driven at, I will of course post pics :yh:

Fun fact: 1.63W (what it stabilizes at, 1.75W is the peak) of 520nm, is equivalent to 29W of 445nm if you look at the dot and 15.5W of 445nm if you look at the beam :D
 
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brendon7358 said:
Fun fact: 1.63W... ...of 520nm, is equivalent to 29W of 445nm if you look at the dot and 15.5W of 445nm if you look at the beam :D
Click to expand...

Those calculations are often wildely inaccurate,
(especially towards the violet end of the spectrum).

Please post beam shots when you receive it ;)
 
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Yea some very efficient ones will on a fast response sensor @ 2.4A peak above 1.7W but they are quick to fall. Most fall between 1.4W and 1.5W @ 2.4A.:beer:
 
Wow so crazy im dying to see pics of the beam, must be bright as hell damn!
 
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