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ArcticMyst Security by Avery

Which laser should I get?

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Jul 28, 2015
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Hi! I'm new to the forum and planning on buying my first green laser. But there's so many to choose from and I don't know anything about them so hopefully some of you can tell me what I should get.

I just want it for shining a beam in the sky at night. So I want as big fat bright, long distance beam I can get, without spending loads.
 





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Mar 22, 2015
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there are a million threads here asking the same thing, so please use the search next time. for you i would reccomend one of these lasers, over 50mW: HL 520nm 30mW-500mW

they aren't cheap but they are very high quality, from a good manufacturer.
 
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Sorry, I know it must be asked all the time. I did have a good look in the reviews section but there's just infinite ones to choose from I wouldn't know where to start.

Thanks anyway though. I prefer to buy one from a reputable manufacturer like you said than a cheap dodgy one. Bit more than I wanted to pay, but you pay for quality I suppose.

I had been looking at ones up to £15 on dx.com. Like this E-smart SDL 303 'says' it's 200mw for £7.61:

E-smart High Power Green Laser Pen - Black (1 x 18650) - Free Shipping - DealExtreme

Out of interest, why did you recommend a 520nm forest green one? What's the difference to a 532 one? Just different colour? Do you think the forest green one looks better/more visible?
 
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Mar 22, 2015
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good question! a 520nm laser is generally a direct diode laser, meaning it has one electronic component generating the laser light, so it doesn't have warm up time and has very little power fluctuation compared to DPSS, imagine it like an LED that emits coherent polarized light, unlike a normal LED. they do have drawbacks though, but nothing terrible in terms of the green diode lasers.

DPSS lasers (the 532nm green lasers) or "Diode Pumped Solid State" lasers are more complicated. They work by using laser diodes to excite a laser crystal in order to make it emit laser light. this is much less efficient, as energy is lost while "pumping" the laser crystal (pumping is the term for what i just described). DPSS lasers are less efficient, sensitive to temperature, and less stable than diode lasers, however have excellent divergence and have very narrow linewidths, making them very useful for lab applications, but less suitable in pointers and handhelds than diode lasers. 532nm lasers in particular work like this:

a laser diode emiting at 808nm pumps a Nd:YVO or Nd:YAG laser crystal, which starts lasing at 1064nm, and then that light is passed through a KTP crystal to double the frequency to 532nm, a green color. during these steps, energy is lost, making them much less efficient.

overall, 520nm will be much more stable and efficient, however wont have as nice of a beam, and is more expensive. hope this answers your question well. be safe too, get some safety glasses, i recommend these for a relatively low power first time laser: http://www.amazon.com/HDE-Protectio...38134756&sr=8-1&keywords=laser+safety+glasses but in the future if you get more powerful lasers, never cut back on safety.

i recommend a simple google search on these in case you were wondering:
Nd:YVO stands for Neodymium doped Yttrium Orthovanadate
Nd:YAG stands for Neodymium doped Yttrium Aluminum Garnet.
KTP stands for Potassium Titanyl Phosphate.
 
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^I would also like to add the following:

It isn't a huge deal breaker, but diode lasers wavelength tend to shift depending on how they are driven while DPSS lasers remain at the same wavelength :)

-Alex
 
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It isn't a huge deal breaker, but diode lasers wavelength tend to shift depending on how they are driven while DPSS lasers remain at the same wavelength :)

-Alex

yes, but you probably wouldn't notice unless your super into lasers like this guy ^ XD
 
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Thanks for the info Micheal. There seems pros and cons then with the 520nm laser.

I like the 520nm for the diode technology as you said the beam is narrower on the dpss 532nm laser, I'd prefer the thicker diode beam for pointing a beam in the sky.

But then you said the 520nm diode laser won't have as nice of a beam? The beam is the most important thing to me, I'm less concerned about efficiency tbh.
 
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H BraveDave, welcome to the forum :wave:
You have received great info above from those members for sure and I would go with green as you want the visibility.

You state, "The beam is the most important thing to me"
It is up to you to decide if you want a thin or thick beam. They both are visible of course but I have seen people like the thin beam as it is "denser" as all the energy is in the very thin beam and I have seen others love the thicker beam like a "light saber". It is up to you in the end. I will say you can't go wrong with either one :D
 
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But then you said the 520nm diode laser won't have as nice of a beam? The beam is the most important thing to me, I'm less concerned about efficiency tbh.

it wont be very noticeable with those green diodes, i think they have good divergence. i meant that the spot wouldn't be perfectly circular and would have more splash than a DPSS laser. you wouldn't notice it really, side by side a DPSS and diode green laser shinning up into the sky would look very similar, other than the color.
 

APEX1

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you want a decent "greenie" without spending loads of money???? good luck with that lol
honestly I'd go with a 520 in a survival laser host. easy to build but the price of the diode will NOT be easy on your wallet!
 
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you want a decent "greenie" without spending loads of money???? good luck with that lol
honestly I'd go with a 520 in a survival laser host. easy to build but the price of the diode will NOT be easy on your wallet!

idk if he wants to build one, so i think he should just go a for a laserbtb 120mW 520nm laser. 120 instead of 100 because i don't know what type of diode is outputting 100mW in the green range so it would be better to get the 120mW one.
 

BowtieGuy

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BraveDave, if you're looking for a nice beam either of those will look good; the dot from the 532nm will probably look better, but not by a lot.
As Micheal said, the beams will be similar, and if that's what you're looking for it's just a personal preference as to which one you would like.

Here's a Link to a thead I made that has a couple of 520/532 comparison photos in it, maybe it will help.

Edit - type in "520nm 532nm comparison" in search bar at the bottom of the page for many more comparisons.
 
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Joined
Aug 26, 2015
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Hi,
I Am trying to replace a green laser pointer that I lost several years ago.

http://www.woot.com/offers/green-laser-pointer-mar-26

It shone for miles and the beam was very compact and bright. I was hoping someone here could tell me which type I should get for long distance and a clear, narrow beam?
Thanks
 




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