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ArcticMyst Security by Avery

Beam Artifact

Joined
May 18, 2008
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I made a post a couple of months ago asking about a beam artifact from my B.R.  
Every diode Ive tried has done this.  i couldn't get a good photo, and tried to explain it.  The topic was just sort of dismissed.  A couple of people said they couldn't get a good focus, but no one really complained.  
I just saw this post in the green laser forum, and it's EXACTLY what all my blu-ray diodes have done.  Is it normal?

http://www.laserpointerforums.com/forums/YaBB.pl?num=1217626966

(well, its not exactly what my b.r.'s do.  They curved lines are right next to the central dot on my violets.. they're pretty far away on that green pic.)
 





Joined
Mar 8, 2008
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yup those faint curved lines are pretty normal. Not sure what they're from but I've had a few that do it as well.
 
Joined
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Im thinking the edge of the beam is hitting the side of the opening of the can.
I think a couple of people have de-canned theirs. If so, and you see this post, do yours have those lines?

not that it matters.. I did try to un-can one of mine, and ended up w/ an led. I won't be trying again!
 

IgorT

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If all your blu rays do this and you can't take a picture of it, are you sure you're not just seeing things?
Blu rays at this power level have a weird effect on our perception. You can see the beam where it's not, or after it is powered down, you can see artifacts around the beam.
People who say they can't get a good focus almost always just don't see it right.


Do this: Shine the beam PAST a piece of white paper from a short distance. The beam should just barelly miss the paper. Then rotate the laser.

This way you will see what is around the beam, without the bright spot influencing your vision. Bright blue fluorescence will also make it easier for you to see what is around, and then you can capture it on a camera.


All you will see there is a faint circle and two "wings" 180° opposite from each other.. One of them has stacked lines on the end. This is just normal distortions that the lens projects from the sides of the diode output.
You shouldn't see anything really bright there. It's very faint and spreads very fast, so at a distance, there is not much left. Not enough to be noticable. Even in total darkness, the brightness of the spot alone overpowers the weak distortions..

If you don't find anything special when you do this, then it's not there, and your eyes are just not used to seeing this strange wavelength. When i first saw an 80mW blu ray beam, it gave me hallucinations.
 

Maven

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lol, note to self, igort's drug of choice is blu ray

effects: hallucinogenic

side note: Obtain blu ray to test effects on self
 
Joined
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Messages
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IgorT said:
All you will see there is a faint circle and two "wings" 180° opposite from each other.. One of them has stacked lines on the end. This is just normal distortions that the lens projects from the sides of the diode output.
You shouldn't see anything really bright there. It's very faint and spreads very fast, so at a distance, there is not much left. Not enough to be noticable. Even in total darkness, the brightness of the spot alone overpowers the weak distortions..

That's exactly what I see. I've had a few which were worse than others.
 

IgorT

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wicked1 said:
That's exactly what I see.  I've had a few which were worse than others.

I wanted to post pictures of it last night, but my computer was acting up, and i couldn't edit them..


Here they are.. This is a combined picture of two sides, opposite from each other. I couldn't match them up perfectly, but you can see what is around the beam..
The two "wings" are different from each other, but they do stand out. Up and down is cleaner, and only the round middle distortion is visible.


Every diode laser with a collimator lens does this. What it looks like depends on the shape of the diode output. The edges of the wider axis of the output do not get collimated into the beam, but spread off to the side.

My 6x also has these wings, but they look a little different.
 

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IgorT

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Maven said:
lol, note to self, igort's drug of choice is blu ray
effects: hallucinogenic

Oh my, did i say too much?


Yeah, my first 80mW blu ray was a little hallucinogenic. But it only took a week or two before i developed tolerance..

Now i need higher purity 405nm. So GooeyGus hooked me up with a 6x.. After i become tolerant to this i will need an 8x, then a 10x.. Who knows where i'll end up? ::)
 
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IgorT said:
[quote author=Maven link=1217727207/0#4 date=1217739931]lol, note to self, igort's drug of choice is blu ray
effects: hallucinogenic

Who knows where i'll end up? ::)[/quote]

In a dumpster behind the factory in china producing the sleds ;D Looking for a new fix...ehehe


brtaman
 

IgorT

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Well, i heard they are throwing away blu diodes, that are out of specs, and come out at 410nm or more..

That's one dumpster i wouldn't mind digging in.. ;)
 
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Thats a dumpster I would help you raid ;) Imagine a nice 410+nm br running at +150ish mw now that would be a nice beam...damn I just gave myself goosebumps...


thanks
brtaman
 





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