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Repairing an old pointer

stephenkall

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Hello, guys!

I just found a generic old pointer which a relative purchased few years ago. It's a 200mW 405nm Class IIIb blue laser pointer, that uses 2xCR2 3V batteries.

Thing is that this laser was working well by the time it was purchased, but not so much right now... What happens? Light is too dim.
I bought new batteries and measured them to be sure it wasn't a battery issue - and it isn't. Batteries are working great and providing 6.2V.
So I thought there might be some issues with the power button and/or the casing contact, so I dissasembled everything and directly connected (with the help of a couple wires) the batteries to the board - but still the same, just a very dim light.

I tried to gently turn the potentiometer and this is the maximum power it can achieve - if I turn from this position in any direction, the laser will get even dimmer.

It doesn't look like I can disassemble any more than I already did, but I can't figure out what is going on.

I'm attaching some pictures to try to show what I'm talking about, but I know the pictures aren't great - it's quite hard to take a picture of a dim light with a bad cell phone camera.

Do you guys have any idea if anything can be done? Is this even fixable?

Thank you!!
 

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thanhtung

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Do you have any other 405nm diode? And you can test that old driver both an other new diode 405nm, if it run good, —> old diode was die,
If diode not light, —-> 1 in 2 or both old driver and old diode both die!
You can send it to me, i am going to repair it for you, or i can develop your old laser up to 1.5-2w violet :) and blue
 

stephenkall

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Do you have any other 405nm diode? And you can test that old driver both an other new diode 405nm, if it run good, —> old diode was die,
If diode not light, —-> 1 in 2 or both old driver and old diode both die!
You can send it to me, i am going to repair it for you, or i can develop your old laser up to 1.5-2w violet :) and blue
Thanks for the reply! Unfortunatelly, I don't have another diode and/or driver, so it might be impossible to test. Also, looks like this is a cheap laser (I don't know, a new one costs about 20 dollars?), so I believe it would be impracticable to send this overseas to get repaired - it would probably cost a lot more than a new one itself!

But thanks for the help!
 

paul1598419

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It looks like the laser diode LEDed to me. If that is the case, these AAA battery host are available quite inexpensively on eBay. I doubt it would be cost effective to replace the diode.
 

stephenkall

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It looks like the laser diode LEDed to me. If that is the case, these AAA battery host are available quite inexpensively on eBay. I doubt it would be cost effective to replace the diode.
Thanks for the feedback! Sorry for asking you that, but I'm kinda new here... By "LEDed" you mean it's probably dead, right? If that's the case, why would it be beneficial to replace the host? Could you please point me to some material to read about it?

Thank you and best regards!
 

Immo1282

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For a laser diode to "go LED" that means the internal structure of the diode is damaged enough that it no longer properly lases - it'll put out a little splash of light, but it's never going to work properly again. It's dead.

If all you want is a working laser, you may as well buy a new one - since repair by a forum member offering to help is going to cost more than a new one once you factor in shipping. On top of that, it's possible that more than the diode is dead, and in a lot of cheap laser pointers, the components are assembled with glue that makes repair...tricky.

Forum's a great place to learn about lasers - if you start in the Sticky Threads section back on the front page, there's some great threads that have a lot of the basics there :)
 

stephenkall

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For a laser diode to "go LED" that means the internal structure of the diode is damaged enough that it no longer properly lases - it'll put out a little splash of light, but it's never going to work properly again. It's dead.

If all you want is a working laser, you may as well buy a new one - since repair by a forum member offering to help is going to cost more than a new one once you factor in shipping. On top of that, it's possible that more than the diode is dead, and in a lot of cheap laser pointers, the components are assembled with glue that makes repair...tricky.

Forum's a great place to learn about lasers - if you start in the Sticky Threads section back on the front page, there's some great threads that have a lot of the basics there :)
Thanks for the information! I was already browsing the sticky threads this afternoon and indeed there is a lot of useful data there. I always liked to play with lasers but I had no idea that there was a whole hobby built around them, and it is fascinating!

Thank you very much for your assistance!
 

paul1598419

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Thanks for the feedback! Sorry for asking you that, but I'm kinda new here... By "LEDed" you mean it's probably dead, right? If that's the case, why would it be beneficial to replace the host? Could you please point me to some material to read about it?

Thank you and best regards!
Yes, the diode has failed. This happens from COD, or catastrophic optical damage. The small amount of light you still see is all the laser can muster after a failure of this kind. It is noteworthy that the diode still is able to take the current it was before the failure, but it can no longer lase.
 
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hakzaw1

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LEDed means same as Zombied--living dead. (& not coming back)
Are you sure it was once 200 mW? ...ever meter it?
My bet its a 1$ (now) 405 pointer at 50 to 80 mW when new.(now)'''

'' but I had no idea that there was a whole hobby built around them, and it is fascinating! ''
?hobby?
more like an 'addiction' than hobby for most of us...
Its been like this for >10 years.
 

paul1598419

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These AAA battery lasers can be had all day on eBay for about $3.00 each. You might as well buy a new one rather than try to repair this one. You could actually buy several and keep the one you like best for every day use.
 

hakzaw1

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?? 3$-- I see a trio (RGV) for $3 free$hip too.. see at ebay from Alan 'blab1391'. IIRC mine (405) made 40mW
 




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