My green 532 Lasever 150mW is like Frankenstein...

[hobbybob]

It's ALIVE ! ALIVE !!!!

A few weeks ago i destroyed my green lasever 150mW by connecting it to the LSR-1 (also Lasever) PSU of my Blue 80mW.
This was because i could have them measured at a company who were equiped with a Coherent meter.

The afternoon i was packing and the green was in my flightcase.
Since it looked easier to only take the heads and supplies i noticed that the blue used the identical one.

Not having heard about PL yet and all the knowledge there is shared here, i connected my green and it worked. After a while i noticed it was really, really bright... then when connecting it to the original supply it went flickering and when i played with the cables went dead on me.

Expensive lesson learned and i learned about differences in diodes etc...
That evening i bought my 1W green.... as a replacement.

Tonight i decided in great Sam's laserFAQ style to dismantle the green.
It was mounted in Aluminium block, 1 screw holding the diode which was in a nice tube, consisting of 2 parts: the lens tube which i could screw off. and a part holding the Diode, lens, Ktp/Yvo4 crystal and pumpdiode and TEC. This last tube was close by a metal cylinder, i hoped it would twist off, which it didn't.
Applying a little force with two big plyers i was able to force it open (it slided instead of screwed).

When i took it out a green wire was broken.
WAS it broken or did i break it was my question ?
I soldered it back together, hold the diode+crystal housing etc against the tec, pointed it down and away from me (not knowing if there were any IR leaking, since i am waiting on my safety goggles to arrive).
I saw a very fine small dot on the floor , really like 1 mm diameter.
It was bright, but not that it would really really be bright (like my 1W)
Pointing it on the wall showed a small dot (mind you the cylinder with the lenses was not placed over). So maybe the lenses will shape the dot more and make it more "lively".

In a few seconds i could feel temperature rise in the backplate holding the TEC, so i immediately switched off...
Now i am going to built it back together, as it seems now, i repaired my green ;-) Yeah. I repaired something and it emits photons again ;-)

When my powermeter arrives from Rob i can measure it, i suspect the Pump diode took rather a blow from the high voltage. In the worst case i could replace that, for now i like to put it back together and see what it does.

Only thing is, the whole thing is wrapped in white tape, people use in heating (when taps are screwed onto heating tubes...the non sticky white tape. This was used to hold the diode casing against the tec. Then the whole contraption was put back in the tube. I will try to reuse the tape, else i get some of that tape from the store.

Pictures will follow, for now, it emits green light !!!!

The Culprit:


More pictures can be found in this dir:
http://www.xs4all.nl/~hobbybob/laser/RepairGreen150mW

[Doc]

*sings* You lucky bastard.

That tape is called PTFE tape

[hobbybob]

Ok, So teflon tape then ? Since PTFE is the chemical name for teflon right ?
(If nothing sticks to Teflon how do they make the Teflon stick to the pan ?)

Will get me some, trying to reuse the old tape resulted in, well.... let me say that there luckily isn't a mrs Hobbybob in this house ;-) I cursed... Damn that stuff rolls up like...well like something that rolls up.... damn stuff...

As you can see on the picture as well the TEC was mounted using some thermal glue i think (or was it just white thermal paste that hardened ?
When i get the PTFE tape can i put Artic silver cooling paste from my PC (conductive!!!) between the TEC and the diode ?

At this moment i can put the diode part and tec part together like they were since the "glue" broke and it's easy to reposition like it was.
My preference is to scrape of the layer of thermal glue of the diode part, since the TEC surface is squeeky clean only stuff is on the diodepart (metal on the right side of the pic). After removal of the thermal residue i want to put on Artic silver heat conductive paste (very small amount like i do with my processors as well). And then wrap the PTFE tape around.
Would this be a good idea ?
Or should i use the white thermal paste (i also got ?)

Artic silver is so much more heat conductive. Removing the original grey intel crap on my Core i950 and putting my trusted Artic Silver on, lowered the temp on my processor like 15 degrees in idle mode...
Or would this lower the crystal temp so much that i would lower the wavelength of my laser also (was it 0,3nm per degree celsius ?) So that would be 5nm of then (giving what 527 ? or 537 of green ??? And costing me power ?
Well i am ramblin' on... i hope someone can answer my Artic Silver question.

Goodnight to ppl in Europe and goodevening to people in US.

[MechEng3]

This is common....I had one fall aprt like that last year's SELEM. Scrape all the white compound off the TEC and the laser backplate. Then, using the Arctic siler sparingly, re-assemble. You should be good then. Be sure to resolder the thermistor wire back in place. There should be a threaded hole in the rearward side of the laser tec plate. Make sure there is good thermal transaction here....I have mounted small sinks on some with a tiny fan. Atleast the MCA didn't fall off inside! Seen that as well.....mostly 473 units from them. If you can get some Torrseal it is also good to have around. I would only notice a better thermal control and more stable diode temps with this repair.

[heroic]

(If nothing sticks to Teflon how do they make the Teflon stick to the pan ?)

They etch the pan so that the surface is rough and pitted, and melt the teflon into the voids under vacuum. When the teflon is cooled, its stiffness holds it in place.

Teflon tape doesn't conduct heat as well as metal, so be sure to use as little of it as possible.

[Zoof]

I figured the teflon tape was there for temperature insulation and stabilization. My lambdapro green was wrapped in it as well. I never bothered to put it back though.
Here are some pics of my green rebuild after a busted diode (read: learning curve): http://picasaweb.google.com/DrZoof/GreenRepair#

[RGbee]

I figured the teflon tape was there for temperature insulation and stabilization. My lambdapro green was wrapped in it as well. I never bothered to put it back though.
Here are some pics of my green rebuild after a busted diode (read: learning curve): http://picasaweb.google.com/DrZoof/GreenRepair#

Hey Zoof, that wouldn't happen to be a UG series TTL unit you have there?

Adrian

[Zoof]

Hey Zoof, that wouldn't happen to be a UG series TTL unit you have there?
Adrian

Yep, the good old UG TTL.

There was definitely a Frankenstein moment when it came ALIVE again ;-)

But it found a home somewhere else after the repair...

Dimitri, keep us posted on your progress. I've owned a lasever green as well and always wondered what the internal look like.....

[hobbybob]

Well been busy tonight, and it didn't work out.
There was a very tiny dot visible and after a few seconds the light on the supply turned red, and the diode went off. I think i damaged the IR pump diode (is that the correct name?) with the high voltage from the blue supply.
I think i am going to open it up, take really good care of the crystals and stuff and try to replace the diode.

Only thing is, it looks like it's all glued, i'll have to pry it apart, on the other hand, it isn't working now. Only thing is, i don't know what diode is in there, so let the search begin (tomorrow, as it's almost 1 AM now...)

I am curious how much IR is pumped in, sometimes i hear 1 times as much as the green output, some people say only 4 to 5 times as much.
Since this was a Lasever 150, measuring over 170 (according to the previous owner) i am curious how much IR went in, 1 W ? 1,5?

Well keep y'all posted. I also took some pics of my repair, since it didn't work i will make some tomorrow when i take the whole piece apart, any idea's on how to remove the glue/take it apart without breaking stuff ?

[hobbybob]

Well..you know me... as a new member, i keep on reading on PL, forget to eat, sleep and keep on going. Ofcourse i wanted to see before i went to sleep how stuff worked.
So i kept on removing the glue between the aluminium and copper parts and pry them apart using 2 plyers. Without very much force i could take the parts apart.
So now i am stuck with 2 parts (not counting the TEC which is the lowest part, but was already loose:

1. the front optics, crystal and stuff and
2. a cup holding what seems to be a c-mount.

ARE YOU KIDDING ME ? I took lots of photo's which i will place here later, since that will really take some time. But no Shit ? This much light out of such a small thing ?
I never saw a c-mount for real, thought they were bigger. But no way, i still can't believe it.

On the c-mount which is gold, are 4 letters, two on each site:
In the lower left is GJ and in the lower right is XP.
On the sides are no letters. Hopefully someone can ID this diode ?
How much power (and are the high powered ones also that small ????
Unbelievable. Now i at least know where that itsy bitsy eany meany dot came from, this is SO SMALL !

Since it was already broken or gave such low light i decided to keep the TEC against the back, turn it away from me, turn it on and make a photo (all with 2 hands).
I projected it away and to the floor from a distance of 5 cm's.
I could see a pattern of like 6 lines, where the lower 2 or 3 were like 1 cm long and like 4 above of 0.5cm
Like so:

----
----
----
----
--------
--------
--------

But in total this was like 0,5cm high and 1cm wide.
If the diode was ok, would this have been 6 equally long lines ?

Hopefully someone knows what GJ XP means and will i be able to find a replacement.
Also there are 4 wires going in the cup, (photo's tomorrow).
The black goes to the gold strip of the diode, red goes to a screw in the housing, and also green and blue go in, under a lot of gummy/gooey glue like stuff (sensors for temp?).

Will place pictures tomorrow. When someone has advice, i am listening...