Guide for changing lens?

[anne0705]

Hi all!
I have been searching and browsing through LPF, but I haven't seen a single tutorial thread talking about how to change lens in the laser pointer. (For instance, changing from G7 lens go G2 lens and vice versa). I understand that this may be too easy to even write about, but I am pretty new here, and I don't have experience changing lens... I am worried that if I buy a new lens from DTR or Sanwu, I may not know how exactly should I change the lens.. Is it difficult? Does it cost a lot of efforts? Or is it just as easy as changing batteries?

I am really very grateful for all the helps!!



Thank you all!

 

[DTR]

The lens elements on those two are mounted in threaded barrels for compatibility with the common Aixiz styled laser diode mounts/modules(M9X0.5mm). This give them the ability to adjust the collimation and they will just unscrew to remove them and screw them back in to install. This part if you have it in hand will be pretty self evident but what is very important specially as diodes get more powerful and we have some that are running open can is to ensure no contaminates get in the module while the cavity is exposed. A good checklist of things to be aware of:

1. Try to limit how often the lens is removed if possible. Rapid fire hot-swapping should be avoided if possible.
2. As clean an environment as possible when doing a swap, Can of compressed air handy would not hurt.
3. Check the new lens that is going in first just to make sure it did not pick up some dust or other debris on the lens element or threading.
4. If you can hold the laser with the diode facing down(gravity is your friend)
5. After lens is back in try to avoid pointing the laser directly up(gravity is your enemy)
6. If possible on first power up after taking a lens out start with a minimum current just over lasing threshold with the lens just a quarter turn threaded into the module. Make sure the current is just high enough so you can observe the raw output on a wall as you slowing screw the lens in all the way to full collimation. As it gets smaller if something jumps out into the light path giving you a chance to open back up and get it out without causing a runaway meltdown burning up the lens or diode.

It is not really discussed enough but whenever the lens is being taking out exposing the sealed module is the most common way I see diodes go to the grave. Anyway just some things to be thinking of when changing lenses.

 

[anne0705]

These lens elements on those are mounted in threaded barrels for compatibility with the common Aixiz styled laser diode mounts/modules(M9X0.5mm). This give them the ability to adjust the collimation and they will just unscrew to remove them and screw them back in to install. This part if you have it in hand will be pretty self evident but what is very important specially as diodes get more powerful and we have some that are running open can is to ensure no contaminates get in the module while the cavity is exposed. A good checklist of things to be aware of:

1. Try to limit how often the lens is removed if possible. Rapid fire hot-swapping should be avoided if possible.
2. As clean an environment as possible when doing a swap, Can of compressed air handy would not hurt.
3. Check the new lens that is going in first just to make sure it did not pick up some dust or other debris on the lens element or threading.
4. If you can hold the laser with the diode facing down(gravity is your friend)
5. After lens is back in try to avoid pointing the laser directly up(gravity is your enemy)
6. If possible on first start start with low current just over lasing with the lens only a few thread turns in so you can see the output but if there is something in there it will not burn up and then thread the lens in to acclimation to see if something jumps out at you as you go and then if all looks good power up as desired. This is not possible with most portable units using a fixed current driver.

It is not really discussed enough but whenever the lens is being taking out exposing the sealed module is the most common way I see diodes go to the grave. Anyway just some things to be thinking of when changing lenses.

Thank you so much!!

May I ask, do you know that if Sanwu lasers are also compatible with this kind of lens?

 

[paul1598419]

I suppose it depends on which Sanwu laser you are talking about. The 304 ones are just the same 301 or 303 style lasers that every Chinese sellers has, but at a greater price. Those don't use glass lenses and aren't easily changed. The more expensive ones seem to have the same M9X0.5 lens housings, so those should take these kinds of lenses. But, I don't know that all are as easily changed as DTR explained.

 

[DTR]

Not sure about the 304's having Axiz comparable lens threading and might be a pain to swap out. On that you would need to ask Sanwu as it does not say on the site. Might have the top which acts as a focus ring glued on the lens with a stop so it can not be fully unscrewed to discourage disassembly or use of addon/replacement parts not sources from a specific supplier. My Jetlasers unit I got a while back was like that.

Did you have a unit in hand with a G-7 or on the way which you wanted to get a G-2 for? That was the impression I had by your post so Paul has a good point if you don't have a unit yet as these lenses will not work with all lasers and there are some that might accept the M9 lenses but are not designed to be easily serviced.

 

[Encap]

Sanwu sells G2 and G7 replacement lenses in both 7mm holders and 9mm holders. See: https://www.sanwulasers.com/product/lenses

If you have a Sanwu laser --ask Sanwu which one fits your your laser.

If you have a Sanwu 303 or 304 as mentioned above you will probably not be able to change it as it never had either of those lenses to begin with.

 

[DTR]

Sanwu sells G2 and G7 replacement lenses in both 7mm holders and 9mm holders. See: https://www.sanwulasers.com/product/lenses

Took a double take on that one as thought his listing meant M7 threading.
Was trying to compute how that was going to work with a lens element that has a 7mm diameter already.
G-2 is 6.3mm diamater and a good fit for the M9 barrels already. Anyway:
https://laserpointerforums.com/thre...with-sanwu-pocket-lasers.102330/#post-1515643

Ahh... 7mm length so a short barrel and both options are M9X0.5mm barrels. That makes more sense.

 

[Encap]

Took a double take on that one as thought his listing meant M7 threading.
Was trying to compute how that was going to work with a lens element that has a 7mm diameter already.
G-2 is 6.3mm diamater and a good fit for the M9 barrels already. Anyway:
https://laserpointerforums.com/thre...with-sanwu-pocket-lasers.102330/#post-1515643

Ahh... 7mm length so a short barrel and both options are M9X0.5mm barrels. That makes more sense.

Makes sense the way you explain.
I guess he put it that way as the end user taking out a lens can easily see and understand how long the barrel is and both barrel lengths with either lens are used his his products depending on model.