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2.4W 445nm - Focusing/lens issue?

C

clccc

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Hey there, I mostly just lurk here and I only own one laser pointer at the moment. I don't use it too often so it mostly just sits in my desk but today when I pulled it out and turned it on I was having an issue with the beam. It's a 2.4W 445nm, I tried to grab a picture of the problem but it's not easy getting a quality picture of.. light...

There is still a pretty tight focused point but coming out from the point on both sides is a pretty solid line, and from there down is a dimly lit rectangle. Most of it is actually faint - not as defined as it looks in the picture. Attaching the best picture I could grab with my phones camera.

All I've done so far is attempt cleaning it, I'm comfortable diving into this thing if I know what I'd be looking for. If it's not something easily diagnosed just by looking over a few things is there anyone on here (preferably within the US, northeast?) who does repairs?


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First of all, what kind of laser is this? What company?

Second of all, there's nothing to worry about here. This is a standard G-2 lens, this is what G-2 lenses do. They put as much power as possible through the lens, but they sacrifice some beam quality. That is why you are getting that rectangle and the line - it is just normal diode output that the G-2 lens passes. So your laser is working exactly as it should. :beer:
 
I got it on here from Blord, It was never like this before though this started recently.. I wish I could get a better picture, I know its supposed to be that shape, The size of the outer-rectangle in that picture is about 3"x3" when the point is fully in focus though.
 
clccc said:
I got it on here from Blord, It was never like this before though this started recently.. I wish I could get a better picture, I know its supposed to be that shape, The size of the outer-rectangle in that picture is about 3"x3" when the point is fully in focus though.
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Often the rectangle is so faint that you don't notice it for a while. I believe it also becomes more noticeable when your batteries are running low (due to the laser intensity being lower relative to the splash intensity. Did you recently change the lens?
 
I haven't touched anything in it at all, I did just charge the batteries today I guess I could try that again. It just seems like such a huge difference from when I originally bought it until now.

**Just for reference, I put the laser ~12ft away from that wall and the smallest I can get that outer rectangle is 4" wide x 3" high. Definitely doesn't seem close to what it used to be? Although it is strange to me that the point almost looks the same. It's just the outer part that doesn't look right to me.
 
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clccc said:
I haven't touched anything in it at all, I did just charge the batteries today I guess I could try that again. It just seems like such a huge difference from when I originally bought it until now.

**Just for reference, I put the laser ~12ft away from that wall and the smallest I can get that outer rectangle is 4" wide x 3" high. Definitely doesn't seem close to what it used to be? Although it is strange to me that the point almost looks the same. It's just the outer part that doesn't look right to me.
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Lots of things could of happened on its down time. Its also frustrating that these diode's don't focus all that well to begin with.
Make sure your batteries are actually charging to 3.7V to 4.2V if they got below 2.5V at any time they might not recover.
Is the focus knob tight enough on the lens barrel that your focusing right?
How was it stored? Was the lens covered an could of dust or any particals get in and did it get banged around. Its probably not good to keep turning it on as if any thing did get on the lens it could bake in on the lens more.
 
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In the future I'd recommend going through DTR or jayrob. They are much more helpful and have much higher quality
 
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HydroSean said:
In the future I'd recommend going through DTR or jayrob. They are much more helpful and have much higher quality
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Hydro my friend, the Op is looking for some advice:)
It looks like he bought a complete laser from Blord who seems to be a decent builder.
Dtr and Jayrob as you know doesn't supply complete builds but i'm guessing Blord has used their parts.
 
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Blord was an excellent builder and many of us own some of his builds. I don't know why he dropped out but he was a class act all the way. Man there are sure some members that I miss. I would have a really hard time selling anything Blord made. GSS is correct but I understand the mistake Hydro as you were not around then.
I'm mostly wondering about the focusing. Can you turn the lens in far enough that the dot starts to get bigger again? If not then the lens isn't coming close enough to the diode to focus properly. You don't happen to know any specifics such as what diode it is do you? I'm assuming like others have that you are using a G2 lens. The lens housing will look like brass or gold colored and not dark grey or black. Back when he was building he was either offering a G2 or 3 element.
If you really want someone to take a look at it I would do it just because it was built by my friend. Be really careful about any kind of cleaning as that can mess things up in a hurry. A new G2 lens costs about $30 from DTR. Have to be careful about lenses as there are other lenses that are said to be a G2 that are not the same as he sells. If you want a much nicer beam and dot he also sells a 3 element lens for somewhere around $10 that will cut the power down by about a third but look so much nicer.
I didn't really make it clear but that dot is pretty much what I would expect to see with a 445 at that output and a G2 so that's why I'm leaning toward a focusing issue or possibly le something on the lens like others have suggested.
 
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I keep the lens covered whenever it's not being used, It could have possibly rolled around a bit I guess with opening/closing of draws. Yes I bought this as a complete build, I haven't made the dive to building my own yet. :P Soon. I did charge the batteries overnight and they are both testing between 4.15 - 4.2v. I took the lens housing out and made sure the inner ring was tight, the lens looks clean from what I can see. When I loosen the lens focus it does get bigger, at one point turns into an actual circle then just gets so out of focus I can't even really see the light anymore. I don't know what kind of diode it is however when I took the lens out I did take a look and since I don't know a whole lot about this, should half of it look covered? http://i.imgur.com/EX4vOI0.jpg I suppose if it's ruled down to the lens I could try replacing that as an easy-fix. If it's not that then I have an extra lens lying about.
 
To me its sure looks a 9mm 445 NDB7875 and nicely sinked in CU.
Pman, Blord sure did a nice job here, and clccc that's a canned diode which is good as far as being better protected from dust and elements. The window on it looks clean but can't be to sure from a pic. That half covered I think your mentioning is just the laser diode itself as its built under the cans window.
I'm more stuck on a lens issue and like Pman said a 3 element for $10 would be a good test, or take Pman up on his offer as members just don't get better than him:)
By the way do you use a rubber lens cap or something else when not in use?
 
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Just wanted to follow up and say that did it, I put the new 3-element on and bam perfectly focused. Thanks a lot guys saved me buying a new one (yet...)
 
clccc said:
Just wanted to follow up and say that did it, I put the new 3-element on and bam perfectly focused. Thanks a lot guys saved me buying a new one (yet...)
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Nice, I just love it when members help and things go well, and kudos to you for following through:)
 
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