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Any ideas why the laser dot would look like this?

nabzim

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Thanks for the info man I only have 70 percent iso rn so I hope that’ll work fine. Sorry if this sounds stupid haha but where is the diode window located on a laser pointer? If I unscrew the entire top cap with the lenses the diode is right underneath but there’s no little piece of glass over it.
70% should do fine. Use a q-tip to wipe it on. Just don't let it evaporate on its own to dry, you need to use another q-tip or two to "mop" it up dry. Any particles or oils picked up by the isopropanol will want to adhere to the liquid. If you let it evaporate away, you're just re-depositing the crap back onto the lens. You need to physically remove the liquid, while it's still a liquid. Benefit of 70%, is it won't evaporate as quickly as 91% or 99%, so you have a little extra time to wipe it away. Downside is that it won't "grab onto" particles or oils as strongly (the crud will have lower solubility in 70%)

Question:
Does anybody know of a good alternative to q-tips, that won't shed any of it's... "hairs"?
 



nabzim

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You don't even know that? geez
What the f*ck is the point of a forum, if not to provide a place for people who don't know things to ask questions about said things?

Wouldn't it be nice if people could come here, and learn stuff without being harassed for not knowing everything already?

Prick...
 

Anthony P

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70% should do fine. Use a q-tip to wipe it on. Just don't let it evaporate on its own to dry, you need to use another q-tip or two to "mop" it up dry. Any particles or oils picked up by the isopropanol will want to adhere to the liquid. If you let it evaporate away, you're just re-depositing the crap back onto the lens. You need to physically remove the liquid, while it's still a liquid. Benefit of 70%, is it won't evaporate as quickly as 91% or 99%, so you have a little extra time to wipe it away. Downside is that it won't "grab onto" particles or oils as strongly (the crud will have lower solubility in 70%)

Question:
Does anybody know of a good alternative to q-tips, that won't shed any of it's... "hairs"?
I have had pretty good luck with using canned air to blow the liquid off.
 

RedCowboy

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Thanks for the info man I only have 70 percent iso rn so I hope that’ll work fine. Sorry if this sounds stupid haha but where is the diode window located on a laser pointer? If I unscrew the entire top cap with the lenses the diode is right underneath but there’s no little piece of glass over it.

I don't use any kind of solvents or iso alcohol, you don't want to remove any AR coatings and if your lens is acrylic you can destroy it easily, I use ZEISS brand lens wipes, the bausch and lomb would likley also be good, you can get them at wallymart or flebay.

Note: They come pre-packaged as individual use towelettes.

 

Unown (WILD)

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What the f*ck is the point of a forum, if not to provide a place for people who don't know things to ask questions about said things?

Wouldn't it be nice if people could come here, and learn stuff without being harassed for not knowing everything already?

Prick...
Name calling, real nice
 

RA_pierce

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70% should do fine. Use a q-tip to wipe it on. Just don't let it evaporate on its own to dry, you need to use another q-tip or two to "mop" it up dry. Any particles or oils picked up by the isopropanol will want to adhere to the liquid. If you let it evaporate away, you're just re-depositing the crap back onto the lens. You need to physically remove the liquid, while it's still a liquid. Benefit of 70%, is it won't evaporate as quickly as 91% or 99%, so you have a little extra time to wipe it away. Downside is that it won't "grab onto" particles or oils as strongly (the crud will have lower solubility in 70%)

Question:
Does anybody know of a good alternative to q-tips, that won't shed any of it's... "hairs"?
As RedCowboy suggests, there are some towlettes that can be purchased from photo stores or online.
Just note the ingredient list for things that are safe for optics.
A clean, high quality microfiber cloth is also pretty good for this.
I use Kimwipes in the lab for optical instruments. They don't produce much lint and the box is anti-static.
I think they can be purchased commercially.
 

nabzim

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I have had pretty good luck with using canned air to blow the liquid off.
I like that idea. I don't have any canned air though... But I have a 150 psi air compressor in my garage! I will give it a try next time I clean my laser lens. I have a feeling it would only work well with small surfaces, like a laser lens. Anything bigger, like a mirror, and you'd just be pushing the liquid around until it evaporates!
Cheers!
 

nabzim

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As RedCowboy suggests, there are some towlettes that can be purchased from photo stores or online.
Just note the ingredient list for things that are safe for optics.
A clean, high quality microfiber cloth is also pretty good for this.
I use Kimwipes in the lab for optical instruments. They don't produce much lint and the box is anti-static.
I think they can be purchased commercially.
Oh! I missed that... My bad...
I have actually been wanting to buy Kimwipes for ages, ever since first using them in my first chemistry lab class (I am a chem major student). Since then, I've noticed they're a standard supply in every single chemistry lab I've ever been in!
Thank you for reminding me about those! I'll put them on my Amazon wish list so I remember to get some soon.
 

nabzim

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I don't use any kind of solvents or iso alcohol, you don't want to remove any AR coatings and if your lens is acrylic you can destroy it easily, I use ZEISS brand lens wipes, the bausch and lomb would likley also be good, you can get them at wallymart or flebay.

Note: They come pre-packaged as individual use towelettes.

Alcohol is actually pretty safe to use for almost everything... Other solvents are more questionable...
The one and only solvent I would avoid using on most things, is acetone! That one, you absolutely need to be sure it's safe with the material your cleaning, before using it.

I have destroyed my glasses with acetone in the past. I was working with some very low viscosity cyanoacrylate glue, and accidentally spattered some on my glasses. I was really glad I was wearing my glasses, since it hit my lenses instead of going in my eyes... but I proceeded to clean with acetone, since, that's the solvent you need to use with super glue, since alcohol will cause it to cure instantly. I knew the lenses were polycarbonate lenses, but I didn't bother to look up it's solubility in acetone, because I had to act quickly before the glue cured, and I thought, "oh it's polycarbonate, the strongest and bestest plastic evar!" I was WRONG!
Once the acetone reached the edge of the lens, it seeped in and completely shattered the lens!
Not a fun way to learn... but now I know:
Never point a bottle of super glue towards your face to look down inside the nozzle, whilst squeezing the bottle to check if the nozzle is clogged!! 😆
 

Anthony P

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Air from compressor may be oily. There are filters available for them, but I never tried. Also, be careful with alcohol on acrylic lenses due to crazing.
 

RA_pierce

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I like that idea. I don't have any canned air though... But I have a 150 psi air compressor in my garage! I will give it a try next time I clean my laser lens. I have a feeling it would only work well with small surfaces, like a laser lens. Anything bigger, like a mirror, and you'd just be pushing the liquid around until it evaporates!
Cheers!
Just be sure your compressor has a good filter on it.
If it's an oil lubricated compressor you can get some of that junk on your optics. It could also potentially blow metal (or other material) dust at your optics at high velocity.
 

Smog92

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Hey guys here’s a pic of the dot from one of my lasers at around 30 feet away the dot is completely centered up close but looks weird from far away. Keep in mind the bright part on the left is where the actual dot is and the rest is light leaking out the side. View attachment 70729
Its melted. 😔 the collimator. Because its not from crystal was however from hardened plastic. I think it is because at me was the same. But for 30 40 € aready are good ones Hope i helped
 

kecked

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That’s a diffraction ring and usually a sign of quality optics. Nice beam feel lucky. It can Also be a reflection so try a piece of paper on the housing and see if it goes away. If not it’s in the diode and would require a spatial filter....not worth it. Can’t explain the wood grain pattern sorry(kidding).

really think Diffraction see how it repeats on the out ring the same as the inner ring.

as for the rest of this thread. Geez stop drinking energy drinks during a pandemic and go for a walk.
 

FireMyLaser

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It may be that the lens diameter is too too small for its focal length in combination with that diode, causing the beam to spill beyond the edge of the lens and scatter light.

long focal length.png
 

FireMyLaser

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You get a fat beam by using a lens with a long focal length (low magnification), and a large enough diameter to catch all the light from the diode. Otherwise the beam size gets clipped by however large the lens diameter is and possibly create unwanted artifacts.
 




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