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So I hear 532nm DPSS has best divergence

Rifter

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So which module has best divergence? Power not so relevant as long as its between 20-100mw
 





IsaacT

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This is a very similar thread to your "which diode has best divergence" thread. Instead of beginning a new thread, next time simply edit your other thread to reflect your new query as it is the same subject.
 

Rifter

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This is a very similar thread to your "which diode has best divergence" thread. Instead of beginning a new thread, next time simply edit your other thread to reflect your new query as it is the same subject.

I wanted it in the green laser section and did not see a way to Move it in the edit thread options.
 

IWIRE

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I wanted it in the green laser section and did not see a way to Move it in the edit thread options.

I think it's called the "Delete" button. Then you make your new thread where you want.
This seems like a different thread. The title states you have found the info you want.
I guess I don't understand.
I would get the 532nm DPSS module. Do I win a cookie or sumthin' ?
 
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you heard wrong. I used to own a 2mrad 532nm, not much better than a 445nm multi mode.

532nm simply tend to have cleaner beams. 1.5mrad is pretty typical, but the LPC 826 I mentioned in your other thread would smoke that number, in a good way

the Lasermax genesis sight I have has superb divergence, but is only 5mW, costs >$200, and is made to go on a picatinny rail
 
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IWIRE

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you heard wrong. I used to own a 2mrad 532nm, not much better than a 445nm multi mode.

532nm simply tend to have cleaner beams. 1.5mrad is pretty typical, but the LPC 826 I mentioned in your other thread would smoke that number, in a good way
Wow. It does seem like with DPSS there is a lot of luck of the draw.
I would love to build one someday. I think I found a build that's going to keep me busy building and working overtime to fund it for a while.
 
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It depends on the unit, jetlasers PL-E pros have bad divergence for a 532nm, but are more powerful, you just have to look for the smallest number possible in front of the "mrad"

the best I have seen is .9mrad for 532nm, (lower is possible, but by no means common or cheap) still not as good as the LPC 826. I confirmed the dot of mine is visible, and stays small, for over 1 mile at night. it's truly incredible, just a bummer that ~300mW of 660nm is not too bright. still, the beam is visible at night, especially when viewing the beam at a small angle. or really big one, depending on how you look at it. despite being relatively dim compared to my other units, it's incredible divergence means that beam will stay tight, and therefore more visible, long after many of my other units have "fanned out"

basically, 90 degrees relative to beam (aka perpendicular)= worst visiblity of beam

1 degree, or 179 degrees, = very good beam visibility
 

Rifter

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It depends on the unit, jetlasers PL-E pros have bad divergence for a 532nm, but are more powerful, you just have to look for the smallest number possible in front of the "mrad"

the best I have seen is .9mrad for 532nm, (lower is possible, but by no means common or cheap) still not as good as the LPC 826. I confirmed the dot of mine is visible, and stays small, for over 1 mile at night. it's truly incredible, just a bummer that ~300mW of 660nm is not too bright. still, the beam is visible at night, especially when viewing the beam at a small angle. or really big one, depending on how you look at it. despite being relatively dim compared to my other units, it's incredible divergence means that beam will stay tight, and therefore more visible, long after many of my other units have "fanned out"

basically, 90 degrees relative to beam (aka perpendicular)= worst visiblity of beam

1 degree, or 179 degrees, = very good beam visibility

Yeah I have a lpc 826 from survival lasers, it's awesome and I love It but as you mention 660nm is just not a very visible color.

I'm hoping to beat the 826's divergence with another more visible spectrum laser. But I have a feeling I'm going to spend a lot of money on beam expanders when I get some more high powered lasers built.
 

IsaacT

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Another thing that helps divergence is putting the lens in the right spot. A lens slightly off of best position can mean the difference between 1mRad and 2.5mRad. If you have trouble with yours try adjusting the lens. Chinese companies don't always get it right.
 
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you heard wrong. I used to own a 2mrad 532nm, not much better than a 445nm multi mode.

532nm simply tend to have cleaner beams. 1.5mrad is pretty typical, but the LPC 826 I mentioned in your other thread would smoke that number, in a good way

the Lasermax genesis sight I have has superb divergence, but is only 5mW, costs >$200, and is made to go on a picatinny rail

Agreed, DPSS has thin beams but not necessarily best divergence. My green is ok - the dot at distance is not much smaller than my blue - and my Rigel has pretty bad divergence (but I suspect that's because it's very overspec and pushing its limits). On the other hand my single mode red 635 has by far the smallest and roundest dot of all my lasers.
 
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It all just depends on the quality and preparation of the optical surfaces, and the spacing between them.
 
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What is typical divergence for an uncorrected raw 532nm output for a typical 12mm module before correcting lenses, anybody know?

Anybody know length of dpss resonant cavity?

If you are very concerned about divergence, use bigger lenses ;)
 
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Those all vary with the specs of the laser and type of cavity...

Linear ones can be as small as an inch or two...ranging up to several feet. :tinfoil:

Raw output has to do with the output surface, cavity spacing, and pump diameter mostly. But generally raw output is similar to be B&W Tek heads/HeNes in most well made cases.
 
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yeah - starting several threads on or about the say day and a lot alike begins to make you look like you are post building- and your Blue laser thread is in the wrong section-- it clearly belongs in 'Blue lasers'

You also have made a very common error in your thinking about power-- to 'double' 10 mW you need 40 mW (its a factor of X4 NOT X2)of the same or nearly same wavelength- you cannot compare colors like you do-- thus for a laser to be '10x' as bright you need more mW than is really possible..
Personally I would hold off buying green diodes as in the past prices have always dropped- the very first 5mW 405s at GreedBay went fot > $140- I know because i JUST HAD to have one- now the same power diode can be had for less than $10
and a 50 TO 100mW - '5 mw' (Ebay pulls listings if you say it has more than 5mW)
these can be had for less than 3$ as you already know- of course they have NO TIME to test these before shipping so you can not expect the same from each batch and sometimes they send a dud. no biggy- at ~$2 each -- 405 is the hardest to see of all the visible weavelengths BUT its awesome around Day glo items and GITD stuff- like a black-light on crack/speed/ and coke DO NOT EVER allow children to 'play' with any laser especially a 405- they are amoung the fasteest burners and due to the VERY small spot size the power is concentrated-- our eyes do not see 405 as being 'bright' & thus your pupils will be dialated allowing even more laser light to enter your eyes where your eye's lens multiplies the power MUCH more-- I direct eye shot from a 50mw 405 pointer can damage your retina- in an instant- I suspect my blurry vision is due to many years around lasers and lasershows -- time to get a new eye exam(its been about 4 yrs) DO NOT assume you got no damage because you feel no pain- our eyes have no pain receptors--

As mentioned you can copy posts and save them- then go back and delete any you dont need after you paste some together-- for some edits you need to first click 'go advance' like changing the title of your thread or deleting it alltogether.

I would not bother with that -- just keep it in mind for the future-- & search well before making a new thread--

good luck
hak
 





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