JDSU Green OC alignment succes

Ok so last year at SELEM I bought JDSU dpss green unit.
However when I got it home it did not work. so i sent it for Dr. Sam to look at and he sent me a functioning unit (laser B later on ) that emitted green light, But only as a splotch. so after opening it I noticed that the crystal was chipped. and upon putting it together I knocked the KTP of its mount ( In my defense it had obviously been repaired before As the door to the Optical cavity was taped shut. Also the crystal looked to have been re glued ) so I put it way until a few weeks ago.

So long story short I told Sam I wanted to try to replace the KTP and he sent me another head.(laser C ) Also emitted a splotch.
So after tinkering with the KTP mount trying to align the crystal for a wile I gave up.

So I gutted laser B For its pump diode but after De-soldering the Robin cable and circuit board off it I ran into a bottleneck The 2 halves of the module were soldered together.



So just before I gave up I heard a raddled noise inside upon investigation I noticed a little cylinder inside through a screw hole.



Gee could it be more optics

so I turned to laser-head C to test.
I turned on the head took out the setscrew and nudged the cylinder with a toothpick.
All of a sudden the Transverse mode changed.
So I messed with it for a wile each time going through weird transverse modes.




Then al of a sudden the power jumped and it stabilized at TEM00 or near it



Long story short again I re-soldered laser-head B back together and did the same thing as with head C but lifted the KTP mount higher to avoid chip.
And it worked to just as good ad B and at least 50 mW

More to be updated in post 2

PART 2

•when trying to flatten out the ribbon cables on laser B so the shell of the head would fit on. I Broke the thermistor wire ( or I think its a thermistor) Oops

•So now the laser won't respond UGGG :gun:
•I thought Ah what the heck might as well try again to get the unit apart.


•So I clamped it in my vise and pressed on the diode segment (the part not connected to the TEC ) with my mechanical press until POP it came off (this was possible because I forgot to put screws back in when I took the circuit off the first time). (Turns out its not soldered; its stuck together with metal tape.)
•This revealed both the diode and that mysterious Cylinder from post one.

• The cylinder

•So I then set the laser down and the cylinder falls out reveling some strange dark red filter on the back of it ( I assume to stop green light from getting back to the diode)



•Behind where the Cylinder was revealed another lens ( remember this is still before ether crystal.


I was not able to find the thermistor I thought it may have gone into the cavity but I think its just at the bottom of that hole filled with blue Epoxy.

So now more pics

•KTP Crystal mount with broken face


( EDIT...
I almost forgot here is the Nd:YVO4 crystal

I cant disect any further because the holes to put the Allen-wrench through are blocked by this plate with the same blue epoxy holding it on
)
•Board on laser pump diode block

So now what
Well
•This laser (laser B) has the good TEC------ Do I dare try to get it out and put it in laser C

•Do De solder the board of the back of the Diode reassemble the laser
block and feed the diode current.

•Take diode to fix aixiz green laser
•or......
----------------------------------------------------------
•Also On a side note
I was Using my bench power supply to give the driver 5 volts and I noticed
something strange.

when powered on
•Laser C (with broken TEC ) would start up and take 5V at around .5 amp
and bounce to 1.05 amp when laser turned on.
• However with laser B ----It would start up and the current would bounce
all over the place needing form 0-5 amps mostly around 4-5 amp and
would only stable out ( Somewhat ) when laser turned on and would hover
at 5.1 amp

Does a small rectangular TEC ( same dimensions as the ones in B&W 473 units) really need 4 amps. or was there something else I missed.

Nice work :beer:

Something about getting your DPSS just right, that makes one all tingly inside :bday:

Congrats man :beer:

Jim

BUMP Look at post 2 for part 2 LOL :thanks:

BUMP Part 3 TIME :wave:

I got laser-head B working :na::na::na:

I decided to take off the circuit from the laser and feed the diode raw current.

First I took the set screw off


•DE-soldered the diode wire shown in Above picture.

•Now the laser is striped of its smart Chips :tinfoil:

•Time to reassembly it.
First goes the Mysterious ( well not any more ) Cylinder.


•Next I screwed back on the diode Block


•Then for the Photo-diode block ( it holds first of the 2 IR filters )



•Next came the KTP crystal mount


•The head in all its Naked shame :crackup:




•And finally i hooked My bench power-supply directly up to the diode and gave it 2.1V at .95A and turned it on and to my surprise instant green
A few seconds with an Allen wrench on the KTP mount and the familiar 3 dot pattern