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Dragon Lasers 1W Spartan

ZapU

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My apologies twhite. The pics weren't for you. I assume you knew the basics. They are for the ones that don't understand optics and divergence, posting on or reading this thread.

Nothing strange in my theory. I have stated that my divergence is worse with the 405-G-1, nearly twice as bad. Probably close the the divergence of the Spartan. Same info from Jayrob.

I have the 405 in my G2, and an O-like 405/445 (very similar to an Aixiz) in my G1. I like the narrower beam better. I posted a thread on different lens here.. I acquired the O-like later.

I like the ability to put in or adjust whatever lens I wish in the "imperfect" Arctic.
 
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Trevor

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Nothing strange in my theory. I have stated that my divergence is worse with the 405-G-1, nearly twice as bad. Probably close the the divergence of the Spartan. Same info from Jayrob.
So, we have a trend - but not one we can rely on to draw a reliable conclusion. The trend being that a multi-element lens allows one of these diodes to perform better.

I have the 405 in my G2, and an O-like 405/445 (very similar to an Aixiz) in my G1. I like the narrower beam better. I posted a thread on different lens here.. I acquired the O-like later.
I believe the key factor in play here is the lens' proximity to the laser diode. Take my B&W Tek laser for example. I once compared the performance of a 500mm and 35mm focal length lens (single lens, of course) to collimate the (raw crystal) output. When I used the 35mm lens, I of course had a much smaller beam diameter, and therefore a higher divergence. When I switched to the 500mm lens, I had to place it farther from the aperture to focus the beam at infinity, and ultimately achieve something like 0.3mRad divergence.

If I remember correctly, the 405-G-1 sits closer to the laser diode (which renders it more able to collimate more laser output before it could possibly collide with the side of the module and be lost). This feature also creates a smaller beam diameter at the aperture, because the laser light is collimated before it gets to diverge very much at all.

The Aixiz (and similar) lenses sit slightly farther away from the laser diode (it doesn't have to be far, given that the raw laser diode output diverges at 45° or more), therefore increasing the diameter (or in this case, dimensions) of the laser beam (and decreasing divergence).

I haven't gone and dug up initial diameter specifications though, so I can't be sure of this theory (at any rate, the information above is still useful to know). Would you take beam diameter measurements at the aperture with both the Aixiz lens and the 405-G-1? If my theory proves false, then I will move on to attempting to acquire more information on the collimating lens used in the Spartan (which is probably going to be difficult unless someone has a dead one). We'll see.

I like the ability to put in or adjust whatever lens I wish in the "imperfect" Arctic.
If you're implying that I hate the Arctic you're incorrect.

-Trevor
 

DrSid

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As I understand it, fast axis means just 'diverging faster then the other axis'. It has nothing to do with output power. And there is fast and 'slow' axis because the emitting area is thin in one dimension and wide in another. The thin dimension diverges faster simply because of diffraction.
The fact that the diode is multimode, that is what makes it stronger. More medium is part of the lasing process. And it can be multimode, because it is not confined to thin area of the substrate. And this also is reason why the emitting area is wider in one dimension, while in singlemode diodes it is almost point source.

Also 'fast' means it diverges fast at the diode itself. Fast divergence at the diode itself is no problem. It still could be perfectly collimated (ie. practically meet theoretical limit based on aperture size ans wavelength), if the divergence would be same in both axes.
The fact that it is not same, is the problem here. You collimate one axis, but the other axis will diverge at different rate. No spherical optics can get around it, and IMHO they all should behave generally same, and you should generally get same divergence for any lens.
IMHO you could get different divergences by masking (thus increasing/accelerating divergence of slow axis), by non spherical optics, by wrong focus, or by wrong measurement or calculation.
 
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Trevor

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As I understand it, fast axis means just 'diverging faster then the other axis'. It has nothing to do with output power. And there is fast and 'slow' axis because the emitting area is thin in one dimension and wide in another. The thin dimension diverges faster simply because of diffraction.
The fact that the diode is multimode, that is what makes it stronger. More medium is part of the lasing process. And it can be multimode, because it is not confined to thin area of the substrate. And this also is reason why the emitting area is wider in one dimension, while in singlemode diodes it is almost point source.

Also 'fast' means it diverges fast at the diode itself. Fast divergence at the diode itself is no problem. It still could be perfectly collimated (ie. practically meet theoretical limit based on aperture size ans wavelength), if the divergence would be same in both axes.
The fact that it is not same, is the problem here. You collimate one axis, but the other axis will diverge at different rate. No spherical optics can get around it, and IMHO they all should behave generally same, and you should generally get same divergence for any lens.
IMHO you could get different divergences by masking (thus increasing/accelerating divergence of slow axis), by non spherical optics, by wrong focus, or by wrong measurement or calculation.
The key is that a larger beam at the aperture with power and focus at infinity remaining constant will always have a lower divergence than a smaller beam.

'Fast' is never used as a blanket term to describe the raw output of bare diodes. It is only used when the diode actually has a fast axis. A bare diode is just said to have a high divergence. Not that it's "fast."

Also, diodes are not a "point source" they way you describe. The closest thing we have to that is raw crystal output from a DPSS system, whose beam can be far less than a millimeter in diameter.

Please read my post more carefully and brush up on theory.

-Trevor
 
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I have read everything here and i bought today a Spartan 1w laser
If i get it , i will open a new topic ... in german and english !!! :D
It will include a few fotos , unboxing fotos + video !

Marvin
 

DrSid

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There is a scientifically proven relationship between power and divergence. It often does not come into play with lasers we work with, however. A larger beam at the aperture with power and focus at infinity remaining constant will always have a lower divergence than a smaller beam.

'Fast' is never used as a blanket term to describe the raw output of bare diodes. It is only used when the diode actually has a fast axis. A bare diode is just said to have a high divergence. Not that it's "fast."

Also, diodes are not a "point source" they way you describe. The closest thing we have to that is raw crystal output from a DPSS system, whose beam can be far less than a millimeter in diameter.

Please read my post more carefully and brush up on theory.

-Trevor
I think we do not really disagree with each other. Anyway I don't understand that part about the power. Size of the beam at aperture surely affects divergence. But power ?
 

Trevor

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I think we do not really disagree with each other. Anyway I don't understand that part about the power. Size of the beam at aperture surely affects divergence. But power ?
Yeah, there are a few theory problems in your post that I addressed. I thought it'd be too nitpicky to address them point-by-point. :p

The reason I say it's affected by output power is that I remember seeing a formula somewhere that computes a theoretical minimum divergence based on diameter, wavelength, and output power. I can't find it at the moment, so we should probably assume that factor is not in play with A1*0 diodes.

-Trevor
 

Trevor

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There is such formula, but there is only aperture size and wavelength in it. Not power.

Gaussian beam - Wikipedia, the free encyclopedia

As for brushing, if it not bothers you, please go point-by-point. I might also have problems with correct phrasing of the problems, as English is not my native language.
Hrm. Maybe I made that up. Disregard that facet of my post until I can come up with where I may or may not have seen that formula. :tired:

-Trevor
 

X FLY

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Nah, It was just a poke at the earlier "built to perfection" comment for the Spartan.
Are you saying then that the Arctic is built better than the Spartan then? The arctic might look cool outside but from inside its crap and way overpriced.

(Im not saying the Spartan is perfect or anything just that its built better than the Arctic)
 
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Trevor

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On an unrelated note, you Spartan owners should take advantage of the threaded head and put beam correction optics right inside it. There should be just enough room. :D

Though my reference point is my CNI PGL-III-M I used to have.



-Trevor
 

X FLY

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DragonLasers should release a new beam expander that fits the Spartan this year :)

(Thats what I've heard from their facebook page)
 

Trevor

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DragonLasers should release a new beam expander that fits the Spartan this year :)

(Thats what I've heard from their facebook page)
...but when get an external attachment when you can fit a several-times expander right in the head? :D

-Trevor
 

ZapU

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Are you saying then that the Arctic is built better than the Spartan then? The arctic might look cool outside but from inside its crap and way overpriced.

(Im not saying the Spartan is perfect or anything just that its built better than the Arctic)
The Spartan is a fine laser and I'm glad you like yours.

How about a side by side comparison?

You mentioned host. Could they pick a more bland host for the Spartan?
The Arctic host not only looks good but it is functional. The Arctic will run two hours continuous with a Tenergy battery, barely getting over 100 F.
How hot does your Spartan get? That is, in the 20 minutes you get out of the CR123 3.0v batteries. The Arctic comes with a non-protected Sanyo and can be fitted with Tenergy protected 18650's. Arctic has a better designed host and uses a better battery design.

Lens. I've already pointed out the differences. Arctic is better.

Safety features. The Arctic has the Smart Switch, a safety pin and a low power "training lens".
Spartan, no safety features. Arctic is better.

Optional lens kit. For $30 more you can get the expanded lens kit with various features, including a close focus lens for burning.
Replaceable lens caps not available for Spartan. Arctic is better.
I understand a beam expander is promised for the Spartan, that would be nice.

Output power. Spartan 1W+, Arctic ~800mW with stock lens. Spartan is better.

Now, about your claim the Arctic is crap inside. I agree early Arctics had issues. Since the G2's have been shipping, very few have reported problems. The battery and goggles were updated. Mine is solid, reliable and functional. Have you been inside a later model G2 to make this claim?

Finally, price. The Arctic costs more, but provides more. The latest included goggles have tested well. You get a quality Sanyo battery and a charger. Now you even get a tripod with it.

It is my opinion the Arctic is a better laser. I wouldn't trade it for a Spartan.
 




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