Author Topic: Any YAG laser experts here ?  (Read 586 times)

Offline BillTodd

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Any YAG laser experts here ?
« on: August 31, 2023, 01:05:30 PM »
I've just been given a pro laser engraver. Its a bit of a monster (150W  @ 1084nm  2.2kW psu with cooler) and broken so I'll probably break it, but I thought I d ask if anyone has  YAG laser experience.

The machine was scrapped with a 'diode low power' fault. I'm guessing this means the 808nm pumping diode has dimmed.

So, how easy would this be to replace the pump
Bill

Offline tom osselton

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Re: Any YAG laser experts here ?
« Reply #1 on: August 31, 2023, 02:00:19 PM »
There are tons of diode laser heads on Amazon Id check them out.

Offline BillTodd

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Re: Any YAG laser experts here ?
« Reply #2 on: September 01, 2023, 10:03:16 AM »
Under the lid ..

Playing with the software, I noticed a setting to extend pump diode warning time , so I am crossing my fingers that there are a few blasts left in this thing .


Bill

Offline BillTodd

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Re: Any YAG laser experts here ?
« Reply #3 on: September 10, 2023, 05:01:26 AM »
Well , the extend warning is only a software thing. The diode pump isn't working :-(

I opened the diode pump box and investigated:
The pump consists of 6  laser diode banks each with 25  chips .  Driving it with a constant current supply I can see a good few chips not working .

The voltage across the array was only 9V or so at 2A - given this is driven by a 50A 45V supply , I can see the need for water cooling.
Bill

Offline BillTodd

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Re: Any YAG laser experts here ?
« Reply #4 on: September 10, 2023, 05:08:37 AM »
BTW these diodes shine down on to the YAG (yttrium aluminium garnet) crystal which is encased in a water jacket for cooling. The red laser light pumps up the electrons in the crystal . When the electrons collapse to their rest state (controlled by a Q switch) they release Infrared photons , which burn the crap out of what ever gets in their way.
Bill