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2 dots problem?

Fiki

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I made my first laser using these instructions as guidelines:
YouTube - How to build a cheap 1000mW+ blue laser


I followed the instructions completely. I did not use the vice to press the diode in however, since I do not have a vice. Perhaps I did not realize it until now, but there are 2 dots when i turn on the laser on something close. I also notice there is some of ambient light shining around the room. Since this is my first laser I was not sure if this was a normal side affect of a do it yourself laser and was curious to know the perspective of more seasoned laser enthusiasts. I uploaded some pictures of both the laser (steampunk design I am happy of :p), the ambient light, and also the two dot problem. My guess is that the diode is misaligned with the lens but I have no way of properly mounting it with a vice (as demonstrated in the video I linked). Any thoughts?

Oh, I also did a search on the forum just to double check this was not posted before but the only thing I could find was that it was a temperature difference (more technical jargon involved).



The Main Problem



The "Guts"



Exterior



Ambient Light
 

RA_pierce

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That's interesting.
I've never seen this with diodes before.

It appears that it may possibly be due to internal reflections but I can't say for sure.

Can you show us some pictures of how the diode is seated in the module?
What lens are you using?
Are there any other optics in the beam path?

If the laser diode actually produces 2 beams I would trade you for a properly functioning one. :D
 

Fiki

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aixiz.com StoreFront

Aixiz lens that I am using.

There are no other optics in the lasers path that I am aware of haha. I can also get pictures of the diode seating in the module. A little late to take it apart at the present.

Edit: Any comment on the ambient light or if it correlates to the double dot?
 
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HIMNL9

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Are you using the standard acrylic lens that come with the aixiz modules with an 1W diode ?

If yes, then probably the problem is that one ..... you melted the lens.

If it's the aixiz glass lens, instead, try to check if there's one of the lenses cracked (they uses 3 lenses, some models with a doublet not glued, some others with the doublet glued, not a single lens, so a crack in one of the lenses in the beam path can cause that result)
 

danefex

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Very strange, as RA_Pierce just said. Check your optics... A reflection of some sort is the only explanation I can think of honestly. That has to be the case, or someone is hiding behind your couch playing a cruel joke on you with another pointer :)
 

RA_pierce

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Also, remove the lens and power up the laser.
Check the beam profile. It should appear as an elliptical "blob" consisting of several bright "stripes."
 

JimBolder

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Did you manage to seat the diode evenly all the way in, without a vice?

It looks like the diode might not be completely seated evenly, and the other dot you see is an internal reflection. If you can't shell out the money for a proper vice, you can use a sturdy C-clamp or something.

Also, the diode will have trouble dissipating heat if it isn't seated properly, and may overheat and fry on you.

Like a HIMNL9 mentioned, are you using the stock acrylic lens? If so, it's probably melting on you. You shouldn't use that lens on anything above 300 mW IIRC. Get an AR coated aixiz glass lens for like $12.00 or so.
 

anselm

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It looks like the diode might not be completely seated evenly,
I thought the same, even if the picture has some funny perspective going on....
To confirm, could OP take another picture where he points camera and laser from the
same place: straight on at the wall, 90degree angle?
 

Meatball

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TWO laser beams from one laser? A two in one deal for sure.

It might help if you didn't cross your eyes while viewing your laser.
 

yobresal

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Yeah I would say the diode is shining through the lens at a poor angle or.....
You could have cracked the diode window with could cause a double beam.
 




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