Help: PCAOM and Reliant 300WC

[ImageLight]

Hey DZ,

I had to rotate the PCAOM to Horzontal Polarization for use with my ILT argon laser to get good throughput.

Mark

[DZ]

DZ, you need to hit the "sweet spot", tune the driver to match the crystal, and checking the polarization is easy. None of these are difficult for a technical person of your caliber. I sent you my cell number. Don't Panic!

Hey Steve, sorry I missed this. I ended up getting busy with work yesterday afternoon. Might try to give you a call later today if you're around. I think I have the driver pretty well peaked up with the crystal and peaked up where on the crystal I was getting the beam thru. It still doesn't seem like I'm getting thru what I should be. Maybe I'm just being overly anal about it, but the thought that the laser might be vertically polarized with this model pcaom reenforces my thinking that I'm loosing too much.

I had to rotate the PCAOM to Horzontal Polarization for use with my ILT argon laser to get good throughput.

Hi Mark! I wish it were that easy, this projector simply does not have enough room to rotate the pcaom. Just to be absolutely sure, today I'm going to try to unbolt the projector and place it on it's side and see what kind of output I get from the pcaom.

[mixedgas]

Dave,
I sorta remember now...
Only a select few if ANY 300 WCs had a internal brewster window added for polarization. It was a common gripe when they first came out. Laserphysics chose pure power over polarization, as most users were still using galvo or dichro color, remember the main use for these was grating arrays in nightclubs. Put a broadband pol cube in front of it and use the waste beam for lumia. You can't blame Kevin Ostler for wanting more power then finesse when he designed this one.

If one were crazy, one would slightly heat the rear mirror assembly to change the cavity length to servo lock one polarization based on a photodiode, a line filter, and piece of cheap plastic Polaroid polarizer. One then might see a nearly constant say 60% polarization. Theory says each line divides itself into two polarizations split 50-50 in power, 90' apart to each other, when running without a internal polarization device. In reality small defects in the mirror and other anisotropy effects cause it to be more like 60-40. Slight changes in tube length cause a unpolarized tube to "roll" its polarization, so if you lock length based on amplitude, it might be much more stable. ( I mainly added this paragraph for "educational" purposes. Even if you went to all that trouble, all adding the servo does is stop or slow the roll through the polarization angles, it does not 100% "prefer" one polarization at that point.


Steve

[DZ]

Dave,
I sorta remember now...
Only a select few if ANY 300 WCs had a internal brewster window added for polarization. It was a common gripe when they first came out. Laserphysics chose pure power over polarization, as most users were still using galvo or dichro color, remember the main use for these was grating arrays in nightclubs. Put a broadband pol cube in front of it and use the waist beam for lumia. You can't blame Kevin Ostler for wanting more power then finesse when he designed this one.

Just finished with rotating the projector. Based on what you say above it would seem that this one is indeed not polarized. In the end, there was no advantage in having the pcaom in either orientation.