C-mount laser diode Blue dpss laser

[starlogic]

Hi Rob

At the moment the laser current is set to minimum

I tested it with my multimeter & the current range on the p.s.u is 500ma -6amps

I also wired a couple of led`s in series & when the current pot was advanced the led`s light & & varied in brightness.

I have lots of electronic`s & laser experience & i will be very carefull with the new C-mounts when i get them.

What is the procedure for realigning the optics ?

or could i be lucky & just need to X&Y align the Diode only


Ritchie

[stanwax]

The proceedure I used - which may be different because of your layout - was to first adjust the diode position. On mine the whole diode block mounted on its own tec could shift left right fore and aft. Yours looks fixed.
You could do with getting some IR protection goggles or use a good tested and known good IR filter (this is what I do) to look at the vanadate. When pumped and lasing the vanadate will glow. This as far as I know is flourecence (i know its wrong but can you spell it ) of the crystal. What you need to do is adjust the pump lens back and forth and side to side so this glow is as small as possible and as bright as possible. Its not dead bright but you will see it easily through IR goggles. Once you have done this the pump ligh will be getting coupled into the vanadate as well or near to as well as possible so maximum lasing will be occuring.
Now yo will need to adjust the OC to get this light passing properly through the cavity - which is formed from the pumped face of the vanadate to the rear facing surface of the OC. You should hopefully get some flashes or mor of blue. If you can get blue I would remove the output lens and shine it onto a wall on the other side of the room - or at least a few feet away. This will give you a blue blob. adjust the OC till this is as bright as poss. and as uniform as poss. A nice bright roundish blob would be ideal. Next I would adjust the SHG crystal to maximise the blue. You will probably find that twealing the OC and the SHG several times will improve it. once you are happy fix everything down and put the output focus lens back in and profile the beam as you want.
sounds easy
Take your time and dont expect it to be done in 10mins. Keep that IR light away from your eyes and good luck!

Rob

PS a tip for aligning the OC - but it only works with the SHG out. I have found that when the OC is reflecting the main lasing light back to the vanadate correctly - and so is aligned the bright glow of the pump light in the vanadate fades away to almost nothing. If you can do this, dropping the SHG back in will almost certainly strike some blue you will still need lots of faff and tweaking to get it optimised.

[starlogic]

Hi Rob

Seems fairly easy to do (hopefully)

I remember the vandate glowing when the laser worked & the optic in front had a blue dot.

I have realigned dpss yellow & green optics in the past & done argon sp168`s years ago.

I know it will take a while but at least i know that microlensed diodes will work .

Dont suppose you have a spare 808 ?

And i also have a pair of goggles


Ritchie

[stanwax]

Ritchie

If you have aligned before then you should be good.
Sorry no spares.
Before xmas I bought 2x 1W and 1x 2W microlensed diodes for a home built DPSS project. The 2W was diverted into my blue - though I think I jumped the gun as it turned out it was a broken tec wire - so the original diode is likely still good but I wouldnt sell you that. I have 1 x1W spare to use in my project as the other was to repair a green laser.

Drop my seller a line and see what he can do - shipping was cheap and it was about £40 inc post I think for the 2W

Rob

[starlogic]

Hi Rob

I contacted him a week or so ago

But he is on holiday & will relist when he gets back

So i will need to be patient & wait

I am very gratefull for the large amount of help you have gave me & i will let you know how i got on with the blue

Ritchie