Its very greeeeeeeeen

[stanwax]

What is a troll ?

Someone who does not know how to use Google

Rob,

I like the sticker on the ammeter CC

It was a promise I made to Dan

Rob

[danielbriggs]

PS - How long do ya think the lamp will last at that current?

I'll put money on sometime before this video can finish playing:

[stanwax]

for 10 mins

Rob

[Doc]

What is a troll ?

Troll

One who posts a deliberately provocative message to a newsgroup or message board with the intention of causing maximum disruption and argument

For instance: Deliberately claiming to having performed absurdly dangerous acts to a safety conscious community in order to provoke a big drama; for an example just read the first part of this thread.

[resonator]

http://www.ebay.co.uk/itm/Laserscope...item19c22db8f5

looks the same laser

[masterpj]

I'll put money on sometime before this video can finish playing:

I see youtube poop:

[dsli_jon]

OK, post-revised...just-saw this pic - http://www.photonlexicon.com/forums/...9&d=1321809282 - clearly not a PV... So, ok - I retract my 'I smell BS' statement, and revise it to '.. I think you need to be a bit clearer on the differences between peaks, Watts and CW-power, when-expressing what you're seeing...' best to simply express what it's actually doing - measured - CW, or Average-Power, in Watts... otherwise, it seems like, yes - you're talking a bit 'Lucy in the Sky with Diamonds'...

The service engineers notes we found inside had a measurement of 34 watts CW at 28 amps lamp current

Here, too, I'd respectfully wager that was Q-switched, *not* CW... Happy to stand corrected, if you can show actual measurements of 34W, CW..

peace...
j

[rszemeti]

Seems you don't understand what "pulse power" means.

again, look at the screen shots thats when it had backed down to 60W @8ms, 20pps

20pps is 1 pulse every 50ms, the power output during the pulse is 60W, for 8ms, then the Qswitch goes dark for 42ms, then repeats. The AVERAGE power will be 9.6W, but the PULSE power will be 60W. Perhaps it would be easier for you to understand if I said "it produces 2ms bursts of 0.3Joules, 20 times a second" ..

Remember that being a medical laser, the thing adjusts itself to deliver a gauranteed value at the end of the fibre, so if you can convince it that its got a 50% lossy fibre on the end, it cranks itself up even harder to deliver the required amoutn of power. Since its well known you can get 30+ watts "CW" (and by CW I obviously mean Q switched ) out of these, I don't think 20W average in in pulses (8ms on, 42ms off) is beyond its capabilities.

Highest I can get on screen is 80W *pulse* power, when the thing is calibrated with a 50% lossy calibrator ... which SHOULD convince it to deliver double that on the output. Theres a screen shot earlier in the thread at the 60W/8ms level.

I guess it also depends what you mean by CW, here, I am taking it to mean "a continous beam, Q switched" as opposed to "20 short pulses a second of Q switched light" .. in true CW mode, without any Q switching, I think you would struggle to get any decent level of output, 10W would be my guess. maybe less, the Laserscopes have a partiuclarly thin KTP, and the conversion efficiency is going to be WAY low. Q switching is a huge win in terms of conversion efficiency. You have to remember that there are two pulse rates going on when a Q switched beam is being pulsed ... firstly there is the 6KHz gating of the RF into the Q switch to deliver the required bursts of laser light into the KTP, then there is the on/off gating of that 6KHz signal by the pulse rate ... so you are actually getting 12 pulses of light, within the 2ms pulse


Whatever, I don;t really give a monkeys whatsit, ive seen it deliver 10W into a known good Ophir meter down a fibre, that had a 65% coupling efficiency, so I know more than that was going in ...and it looks pretty damn awesome.

[dsli_jon]

Seems you don't understand what "pulse power" means.

No, I do - it was merely a bit of 'confusion' from what it seemed you were claiming, here... perhaps you didn't see my 'revised' post...

...(and by CW I obviously mean Q switched ) ...I guess it also depends what you mean by CW, here, I am taking it to mean "a continous beam, Q switched" as opposed to "20 short pulses a second of Q switched light" ..

Ok, this is where the 'confucius' entered... The use of the terminology was just a bit at odds with itself.. CW always = 'continuous wave', as-in, raw optical-power, not Q-switched or pulsed or anything... And, 'Q-switched' is 'pulsed'... 'peaks', are just-that - peaks, within the pulse-train... And, thus 'peak power' - however-spaced, in the pulse-train - is a different measurement from the more 'common-way' of expressing power, in 'Watts', which is really an expression of the 'Average-Power' of that pulse-train...

..Clearly, you understand all this, it was just a bit confusing the way you were presenting it all, my bad...

in true CW mode, without any Q switching, I think you would struggle to get any decent level of output, 10W would be my guess.

Yeah, most of the 700-800 LS-series out there, you could expect 8-9 Watts, CW ..but, some, like the ones with the 'high-power ugrade' (ie: Rob's unit, there...) you could see 15, 16, even 17 Watts, CW...truly impressive.. Those are the ones that are capable of producing 60+ Watts - Average power - when q-switching...

..and it looks pretty damn awesome.

Indeed, Sorry if I pissed in the punch-bowl...
cheers..

j

[rszemeti]

Well, I was trying to keep it simple for the laser-pointer kiddies, if you start talking about Q switched as pulses, they expect to see the beam going on and off, and at 6KHz, it appears as a continuous beam. I suppose I could measure the mark space ratio on the RF gating and find out what the true peak power is! that might be amusing .. again, peak as in tru peak is going to be way high.

It's sort of tempting to strip the controller off it and really open it up to see what can be got out of that deck in full on rock and roll Q switch mode, with as many lossy bits removed from the output chain as possible .. but there again, is it worth the bother? 20W of reliabel q switched beam is enough to play with, more would be overkill ... but there again, we like overkill

I do wonder abou the size of the DI pack on mine .. bit small. Most other YAG's I have owned have had much bigger DI packs, I'll dangle a conductivity tester in the tank one day, see if its working, fires UP OK so I guess it is. I guess anything better than about 20 uS is good?