80W 532nm YAG up and running! :) [Very image heavy]

[tonyaztec]

Ohh, If I can help, let me know. Which club?

Haha, I used to run one outside at Club Ice many years ago but the army stopped us as they changed Keevil airfield flight path.. !!
This one destined for the roof of the biggest club in Somerset...

[Simon]

Ohh, If I can help, let me know. Which club?

Yeah sure. Its Club Neo in Yeovil. I am technical manager of this place and 2 other clubs in Birmingham.

We have a nice hill opposite us where our logo will be projected.....

[The_Doctor]

Without the Q switch, you don't get the dangerous peaks and visibly the beam is dimmer of course.
The upside is that there isn't any "marching ants" as the beam is now true CW.
My original idea was to produce a relatively cheap (excluding power consumption) and powerful beam that is good for high speed scanning.
I hadn't though about compressing the huge beam diameter.... mmmm

Marching ants? You're talking to a guy who took three years to figure out what means 'jelly beans' because I never wanted to ask, and didn't have a laser than did that. I'd always assumed that when told that a Q-switch increased peak at expense of total power, average might look brighter without the switch purely because less power was lost. Although I guess the ants mean a discontinuity that looks brighter. Do you see them in a static beam? My guess is no.. but if no, does the pulse still make the beam look brighter?

The closest I ever got to resolving that was with a Hamamatsu LED with unusually tiny emitter, years ago, pulsed at 3500Hz with small pulse width ratio. In this case when moving it caught attention with beads of sharp light, but when still, looked exactly the same as a CW driven one with same average current. As they looked like point sources at any distance greater than a few feet, I assumed that would guide my understanding of lasers too. So if a static laser beam pulsed rather than CW does look brighter even though there's nothing allowing me to resolve the pulses by eye, there's something else going on, and I don't know what it is.

About the beam diameter, a half-decent telescope or monocular with very clean broadband AR coating might do it for CW without cracking up. Worth a try anyway. At distance the more diverged beam will be safer, and because it's viewed so close to beam axis, might still look good to nearby observers. (Within a half mile on a slightly misty night).

Seconded, that question about club location. I have no transport, but I might still be within range of this sight if I walk far enough.

EDIT:
Seen reply, wasn't there when I started this post. Yeovil's a bit too far for me. Any idea of range for visibility? (Assuming you have clearance for straight-up static beaming).

[Photonbeam]

Congratulations Simon on your acquisition and best of luck collimating the CW beam for scanning. You should be able to move some large scanner mirrors at 12-18K pps. Removal of the Q-switch is an option, but as I recall, the passive insertion loss of the Q-switch (unpowered) is almost negligible. Laserman532 and I did 100W of 532nm straight up out of an abandoned Atlas F missile silo outside Roswell, NM for the millennium 1999-2000 (see my avatar). I not only had to do the usual paperwork for the FAA and CDRH, but also had to get clearance from the military and nearby White Sands missile range. I was invited to tour the FAA control facility and thought it was interesting that along with other landmarks designated on their radar displays, they had marked the location of the 1947 UFO crash site. I can't imagine the hoops you will have to jump through in the UK to project straight up. Please keep us posted.

[Laserman532]

get plenty of spare parts ebay - laserman532 until they are all gone

[Laserman532]

I still have this medal, if there are any challengers...This medal could cross the pond if you fire that beast up at the LEM.

[mixedgas]

Simon, keep the Qswitch so you can ramp the power. The Qswitch has a built in setting that is useful for knocking the power down to a Watt or two for aiming.

Steve

[Pockels]

From memory, Q-switched is definitely brighter, but not significantly brighter than CW to the naked eye - however, peak power will be monstrous. It's the human eye's perception of wavelength that determines the 'brightness' of the beam - You won't perceive the tenfold increase in energy, hence why Q-switched YAG's are inherently dangerous.

Use optics/mirrors specifically coated for high power 532 as well. And keep them squeaky clean or risk permanent damage to the facings (or lens meltdown as has happened in the past)!

[mixedgas]

The Q-Switch aids greatly in increasing the green conversion rate, resulting in brighter beam effects. However, instead of the central 40% of the beam being converted, if the Q-switch is on, more of the large diameter IR beam gets converted and you get the fat, fuzzy, green beam. In my experience CW Green is at best 1/4th the Q-switched power.
Nobody has let me play with an 800, I imagine the beam relay in the 800 series does better at green conversion.

The partial pesticide for the marching ants is to use the fact that Pangolin allows you to store a frame rate for each frame. So if you get good scans at 14 Kpps with the larger scanners, alternate each frame in animation between say 13.7 Kpps and 14.0 Kpps, so the dots land at slightly different places. If you have a still shot like a logo, make a few identical frames with slightly different speeds. This worked Gangbusters with a older green Lee Laser, and worked with a Spektronika CVL.

As for the lift test tower, that video was horrid, they did not effectively use what they had, software wise.

Steve

[Laserman532]

Congratulations Simon on your acquisition and best of luck collimating the CW beam for scanning. You should be able to move some large scanner mirrors at 12-18K pps. Removal of the Q-switch is an option, but as I recall, the passive insertion loss of the Q-switch (unpowered) is almost negligible. Laserman532 and I did 100W of 532nm straight up out of an abandoned Atlas F missile silo outside Roswell, NM for the millennium 1999-2000 (see my avatar). I not only had to do the usual paperwork for the FAA and CDRH, but also had to get clearance from the military and nearby White Sands missile range. I was invited to tour the FAA control facility and thought it was interesting that along with other landmarks designated on their radar displays, they had marked the location of the 1947 UFO crash site. I can't imagine the hoops you will have to jump through in the UK to project straight up. Please keep us posted.

good times - eating at the Dennys was like the bar scene in star wars that weekend...

edit...that was 14 years ago! damn...