Newbie ? about possible dirty G2 Lens

[mikeyjames]

Hi all,
Building my first high powered laser. Got an M462 from DTR with 3 element glass lens. Got a host from Survival Laser with an additional G2 lens.

When the laser is focussed for a large area the lens seems to show some type of psychedelic patterns. I have tried cleaning with Q tip and isopropyl alcohol but it does nothing.

The attached picture isn't the best but it gives an exaggerated look at what I am seeing.

Is this normal for a brand new G2 lens.

Thanks
Mick

 

[DTR]

What that looks like is you tried to clean it but fired the laser up without drying the alcohol first and it boiled it off in that pattern.

 

[DTR]

This is on the lens right? When you turn the lens the pattern turns?

 

[jeffreythe00]

I agree with DTR. Looks like its residue left over from the alcohol. When cleaning lenses with store bought q-tips (like the value packs of 500) they can sometimes leave residue or dust on your lens. That and alcohol can sometimes have impurities that will stay on the lens.

Proper way to clean with alcohol is to take the lens out of the holder "carefully". Get the q-tip a little wet (i usually flick it off so it doesn't soak the lens) and go from one aide to the other in one motion while spinning the q-tip. Then immediately go over it again with the dry side. You don't want to let it dry on the lens because if it has any impurities in it, they will remain on the lens.

I don't generally recommend using Q-tips and alcohol but it works "good enough".

I'm not sure where you live but, if you live anywhere in the US I will offer to clean your lens for you. I have optical grade cleaner here that will get your lens looking like new "assuming" you didn't bake any impurities on to your lens or destroy the coatings.

 

[USAbro]

Use these to clean the lens. Amazon.com: Detail Micro Brushes Paint Touch Up Applicators pack/40: Automotive

 

[mikeyjames]

This is on the lens right? When you turn the lens the pattern turns?

Hi Jordan,
Yes, it spins when I turn the lens. The pattern has been there since I first fired up the laser. Doesn't seem to matter what I do I can't get rid of it.

The diode is great. Measures 2.1w with the G2 and 1.72w with the 3 element. Still not completed yet as I forgot to order battery contact board with the host. So atm I have just installed the module in the heat sink and connecting the battery manually.

The only real drama is me not being used to the power and nearly setting my bedroom on fire

BTW - the status of the green module hasn't changed. I think customs are looking at it. I'll fight them this time if they seize it as from what I understand they have no right to take modules.

Thanks
Mick

 

[mikeyjames]

Use these to clean the lens. Amazon.com: Detail Micro Brushes Paint Touch Up Applicators pack/40: Automotive

Thanks for the info. Will try and source some in Australia.

 

[mikeyjames]

I agree with DTR. Looks like its residue left over from the alcohol. When cleaning lenses with store bought q-tips (like the value packs of 500) they can sometimes leave residue or dust on your lens. That and alcohol can sometimes have impurities that will stay on the lens.

Proper way to clean with alcohol is to take the lens out of the holder "carefully". Get the q-tip a little wet (i usually flick it off so it doesn't soak the lens) and go from one aide to the other in one motion while spinning the q-tip. Then immediately go over it again with the dry side. You don't want to let it dry on the lens because if it has any impurities in it, they will remain on the lens.

I don't generally recommend using Q-tips and alcohol but it works "good enough".

I'm not sure where you live but, if you live anywhere in the US I will offer to clean your lens for you. I have optical grade cleaner here that will get your lens looking like new "assuming" you didn't bake any impurities on to your lens or destroy the coatings.

Appreciate the offer but in Australia. I'm using 99% isopropyl from the local pharmacy. Is this okay?

This forum is turning out to be a nice friendly and helpful bunch of people. Maybe someday I'll be able help someone when I have finished making all of my newbie mistakes.

Thanks
Mick

 

[jeffreythe00]

99% pharmaceutical grade alcohol is fine. Again, just use the method I described above. After cleaning the lens, see if the pattern changes any especially now that we know its on the lens.

 

[mikeyjames]

99% pharmaceutical grade alcohol is fine. Again, just use the method I described above. After cleaning the lens, see if the pattern changes any especially now that we know its on the lens.

I will give it a try tonight when I get home from work.

Cheers
Mick

 

[mikeyjames]

Proper way to clean with alcohol is to take the lens out of the holder "carefully". .

Hi again,
Had a chance to look at it last night and - maybe this is a stupid question - but how do you get the lens out of the holder. I can get the focussing ring off but that's about it.

Thanks again
Mick

 

[The Lightning Stalker]

I would get an alcohol squirt bottle and
hose the thing down before going for the
Q-tips. I find that 70% or 91% actually
works better for removing contaminants than
99%. The water will dissolve polar
molecules and the alcohol takes care of
some of the nonpolar ones. Does the G-2
even come out? I thought it was glued in.

 

[Shakenawake]

I personally have better luck with distilled white vinigar than rubbing alcohol.

1. dip one end of a q tip into the vinigar.
2. with a second q tip, very lightly touch the other q tip's wet end, such that only a tiny amount of vinigar is absorbed in the second q tip's tip
3. use this lightly vinigar damped end to clean the lens, then the dry end. may take a few tries but should work

I use this method to clean all my lenses, and have even made some of the worst diode windows look new as well.

 

[USAbro]

Never thought of vinegar before. Good idea. +rep for you.

 

[mikeyjames]

I personally have better luck with distilled white vinigar than rubbing alcohol.

1. dip one end of a q tip into the vinigar.
2. with a second q tip, very lightly touch the other q tip's wet end, such that only a tiny amount of vinigar is absorbed in the second q tip's tip
3. use this lightly vinigar damped end to clean the lens, then the dry end. may take a few tries but should work

I use this method to clean all my lenses, and have even made some of the worst diode windows look new as well.

Thanks for that. It worked well.

Cheers
Mick