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FrozenGate by Avery

spartan 1w vs arctic s3 beam divergence

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graviton

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I'd like to ask owners of these two models to measure the beam divergence of their lasers and tell the result. Very interesting to have some statistics.
 





And what about the Spartan? There are even no detailed specification at the DL site.
 
hm 3.5mrad, it's huge divergence! It means that either optics is bad or bad focus adjustment. Laser must have 1.5mrad or less. However, maybe this new diode produce not monochromatic light(other wavelengths are present). It also can explain big divergence.
P.S. Sorry for my not very good English, I'm from Ukraine
 
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3.5mm is the beam diameter at the appurature, not the divergence. Divergence would be calculated using those 2 numbers.
 
Yes, I understand. I've calculated the divergence as 1.422/400 and obtained 0.003555 rad. As beam diameter at the aperture is small compared to other values, we can neglect it.
 
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So are there any cases of lower divergence? Someone told about 1.33mrad for arctic. Is it true?
 
You don't need calculator .. just divide the two numbers, and that's it (with reasonable degree of precision).

1.33mRad for Arctic is impossible.
 
DrSid said:
You don't need calculator .. just divide the two numbers, and that's it (with reasonable degree of precision).

1.33mRad for Arctic is impossible.
Click to expand...

Glad mine can do the impossible. Others have reported similar results.

For the mathematically challenged:
pseudonomen137's JScript mRad Calculator

6+ meters (20ft 5in tape measured). 13mm spot. 5mm at aperture (CANT BE 0mm). Measured with caliper. Sorry, no metric yardstick (meterstick? ;)) for the beam shot.


Divergence2.jpg


Beam shot:

DSCF1795-1.jpg


Lets see the beam shot at 6M (20ft) with the Spartan!


Spartan X said:
I can tell you my fast axis is 3.5mm at the opening, and 1.422 meters at 400 meters

http://laserpointerforums.com/search.php
Click to expand...


Plug SpartanX's figures in the calculator and you get 3.5462351343 mRad.
 
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Jeez, did I put 0 mm beam at aperture ?!

:crackup:

Gotta lay off that 445nm goodiness, I can't even see what I'm typing.

Many sorryz folks.
 
ZapU said:
Glad mine can do the impossible. Others have reported similar results.

For the mathematically challenged:
pseudonomen137's JScript mRad Calculator

6+ meters (20ft 5in tape measured). 13mm spot. 5mm at aperture (CANT BE 0mm). Measured with caliper. Sorry, no metric yardstick (meterstick? ;)) for the beam shot.


Lets see the beam shot at 6M (20ft) with the Spartan!

mRad.
Click to expand...

Are you sure you have measured the beam the right angle? There is no way the fast axis is 5mm at the aperture, that's means the arctic has beam correction optics inside, and didn't we find out it hasn't? Beamshot at aperture please...
 
Grix said:
Are you sure you have measured the beam the right angle? There is no way the fast axis is 5mm at the aperture, that's means the arctic has beam correction optics inside, and didn't we find out it hasn't? Beamshot at aperture please...
Click to expand...
Ehh, fast divergent axiz is 5 mm wide at the lens exit, at least in mine 445nm laser which uses same setup as arctic, 3 element 405nm coated lens, no FAC.

Slow axiz is much lower than that, but I'm not exactly sure what to measure since there are like 4 parralel beams each about 0.3 mm wide at slow axiz, all same 5mm fast axiz.

P8240220.jpg
 
I'm pretty sure that the axis with the lowest diameter at aperture is the fast axis, that is why it diverges more and why beam correction optics work by expanding it to make it less divergent.

sdfsg.PNG
 
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With large distances (like 400m) you can neglect the aperture diameter and use only one distance and one size. And only in this case the divergence can be computed directly as size/distance.
As aperture diameter is not easily measured with enough precision, it's better to compute the divergence not from distant size and aperture size, but from distant size, and let's say half-distance size.
Please try to measure the arctic at 100m or so.
 
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