AOM mudulator orientation

[LASERGUY]

Hello all,

Pretty exciting night last night!!!

Since I have some new 50K Laserworld scanners on the way (Courtesy of Blulaser) I realized that my mechanical blanking just won't cut it anymore. (See pic... sorry for the blur)

I use a galvo based retro-reflector configuration for my blue line (Argon laser)... The galvo I use for this blanking setup is the same as my current galvos. Pretty much an on or off system (Can get som analog effect but not quite).. Te speed of blanking to scanning is relatively close to the speed of the scanning.

With the new scanners I am anticipating that the older mechanical blanking just won’t cut it.

Anyways... a while back I won an eBay auction for an AOM... I must have had it for almost 2 years now...
The deal was so good that I was betting on that it was damaged and I was missing a cable.

I managed to finally get the courage to rig the thing up and see if it works..

To my amazement... IT DID!!! so so so cool

Not sure if everyone on the forum has experience with these devices but it really neat!
Its cool to go back to some old school methods (DPSS gets to easy some times)

My question to anyone who has experience...

What is the optimal orientation of an AOM?

I am using an American-60X (Re-gassed seal optics - National laser tubes)... orientation of polarization matters doesn't it?

What’s the orientation of a 60X typically?

There is no in/out designation on the modulator crystal.. Does it matter?

Which way should I tilt.... forwards or backwards?

Is there any general rules of thumbs about AOMs that someone out their could share?

Thanks guys!

Laserguy

[ImageLight]

My 60X is vertically polorized.
Just experiment with the AOM orientation as, your looking for the brightest 1st order
beam after it passes through the crystal when a drive signal is present. Most often
the AOM will produce a 1st order beam in either tilted position. Do you have a Bragg
Mount for the crystal?

Mark

[LASERGUY]

Mark,

Thanks for the reply!

I did just that and it seems to be optimised when I have the AOM positioned vertically...

I do have a simle brag mount... No micrometer adjust or anything
But I was able to optimise the angle fairly well and lock it down.
Its working great!

I wasn't sure if either angle is better.. Forward or away from the RF connector...

I have to take some pics and show it in action

LG

[ImageLight]

Cool, I'm glad it's working for you. We may have met long ago at Fels, I used to work for Scott H. as well. That LFI Rainbow series 5 head was the first real laser projector I got to play with.

[mixedgas]

Usually there is a long side and a short side of the crystal that forms a angle on one end, opposite the transducer which makes the waves. The angle prevents the sound waves from reflecting back down the crystal, and usually the long side goes away from the laser.

Its only a 2 to 5% difference or so if you have it backwards.

You can spot the transducer, its the gold patch bonded to the crystal at right angles to the beam path, and usually has a sweet spot for power right next to it.

I hope that helps.

Steve