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ArcticMyst Security by Avery

My Best HeNe Output So Far

Joined
Oct 12, 2007
Messages
285
Points
28
Awesome HeNe! I love their beams. Yes they are very visible in comparison to VLDs at 650. Even 635s are not as bright with same power. Beam diameter and shape (the beam is quite thin) have a lot to do with how it picks up scatter too.

I've actually taken it outside and shined it around like a pointer (while probably looking like an idiot) but it was worth it :D

Haha now that brings back memories in the late '80s. I did something very similar but with a 5W tube. It was a BARE tube with PowerTech inverter (1" sparks off 9V battery!) and it was cold and snowing. (you see where this is going!)
I was shining it all around admiring the saber like beam in the snow. I do remember it was VERY shaky because it was cold and I was shaking/shivering. Then BAM! It hit me like a bushel of billiard balls! The hot lead arc'd to my thumb and I jumped and everything plunged into the snow! If you've ever seen National Lampoon's Christmas Vacation where Clark was in the attic watching home movies and they come back, pull the cord on the attic master and he falls along with the projector and reels...you get the idea! Same sensation going from such a neat feeling and awe to screaming the words holy shit (and other metaphors of color I won't repeat here!) so loud everyone within a mile can hear it. (in their house!)

I never did get 5mW out of that tube again. It buzzed a lot and the back mirror got chipped. I like those Power Technology Incorporated potted inverter power packs though. They are fun in their own to mess with. :)
 
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DJZ

0
Joined
Aug 27, 2008
Messages
270
Points
0
Hi Daguin, very nice HeNe! Congrats on the fantastic score.

Regarding the conversation about aparent brightness. We've done several tests at the Laser Enthusiasts Meetings held in NC and FL. If I remember correctly, we found that there is nearly a 5X aparent difference between 635nm and 660nm. In our test, we had two identical abstract patterns being scanned and adjusted the brightness to where they appeared to be the same. The 635nm projector was doing around 80mW while the 660nm projector was doing around 380mW.

The pic attached is of a 660nm diode and 635nm diode, both hitting the same scan head, and both running at 200mW.
 

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vk2fro

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Joined
Nov 30, 2009
Messages
1,304
Points
63
nice hene - I'd love to find a big one like that to add to my gas laser collection :)

I think we are ALL guilty of taking a laser of some sort outside to shine around. One time when the new laws weren't in effect (i.e. you'd get a bunch of swat members breaking your door down), I took my NEC ARGON out on the balcony and shined it around. Looks very cool at night. I was lucky to live in a quiet surburban street back then, and no where near a flight path.

I didnt shine it around for long, as the beast was quiet heavy and not exactly "laser pointer" material :)

nordhavn: yes those hene supplies really bite, I got hit by one for a melles groit 5mw tube. Stung like a bull-ant bite.
 
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Joined
Nov 7, 2008
Messages
5,725
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That's a sweet HeNe Dave! It always surprises me how "multimode" with gas lasers is really just a flat-top profile while with solid-state multimode there are typically multiple lobes of output. In the case of gas lasers, when people say multimode they mean multiple transverse modes, right?
 

daguin

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Joined
Mar 29, 2008
Messages
15,989
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That's a sweet HeNe Dave! It always surprises me how "multimode" with gas lasers is really just a flat-top profile while with solid-state multimode there are typically multiple lobes of output. In the case of gas lasers, when people say multimode they mean multiple transverse modes, right?

Yeah. The spot is really a very intricate (and beautiful) pattern. I would need to set up some kind of filter so that the camera could see it.

I have another HeNe (~5mW) that is multi-mode as well. Its divergence is MUCH worse than this one (because it is a very short tube). The 5mW one's spot is about 5 inches at 20 feet! That is huge, BUT it expands the multi-mode spot so much that you can actually see the patterns shifting from one mode to another. I showed it to ScopeGuy20 and EzPk0970 the other day. It is actually very interesting to watch.

There was no visualizer in the air in the above pics.

Peace,
dave
 
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Joined
Oct 12, 2007
Messages
285
Points
28
A pic (or better video!) of that beam expanded would be awesome. Filter it down so it does not overload your sensor. :)
 
Joined
Nov 7, 2008
Messages
5,725
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0
Yeah. The spot is really a very intricate (and beautiful) pattern. I would need to set up some kind of filter so that the camera could see it.

I have another HeNe (~5mW) that is multi-mode as well. Its divergence is MUCH worse than this one (because it is a very short tube). The 5mW one's spot is about 5 inches at 20 feet! That is huge, BUT it expands the multi-mode spot so much that you can actually see the patterns shifting from one mode to another. I showed it to ScopeGuy20 and EzPk0970 the other day. It is actually very interesting to watch.

There was no visualizer in the air in the above pics.

Peace,
dave

Wow. So it does have structure, it just changes rapidly. That explains why the few multimode profile pictures I've seen from gas lasers always look pretty even in terms of power distribution to the camera.

I really need to get a multimode HeNe!
 
Joined
Jan 2, 2009
Messages
11,800
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Hi Daguin, very nice HeNe! Congrats on the fantastic score.

Regarding the conversation about aparent brightness. We've done several tests at the Laser Enthusiasts Meetings held in NC and FL. If I remember correctly, we found that there is nearly a 5X aparent difference between 635nm and 660nm. In our test, we had two identical abstract patterns being scanned and adjusted the brightness to where they appeared to be the same. The 635nm projector was doing around 80mW while the 660nm projector was doing around 380mW.

The pic attached is of a 660nm diode and 635nm diode, both hitting the same scan head, and both running at 200mW.

Thats amazing. Like I said I'm a layman. Thanks for the info.
 
Joined
Oct 19, 2009
Messages
114
Points
0
Hey Dave. I rarely venture into the gas section, but that is very impressive. A whole nother level of laser. Thee things make poiners seem so......insagnificant.....

I like the New Wish on top of the box in the first pic, gives an idea of how big these things are.

Si
 




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