Coherent Novus 2000 2.5W Argon/Ion laser teardown
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- Опубликовано: 13 сен 2024
- Teardown of a Coherent Novus 2000 Ophthalmic argon/ion laser. This is a 2.5W blue/green argon laser used for eye procedures.
If anyone is interested in the laser tube, email tesla500@hotmail.com
The left foot/right foot labels are likely for assistants to know where to place the foot pedal for each doctor during room setup.
Shouldn't be at all hard to get that tube running as you don't need the precision they use to avoid burning people's eyes out.
At least in pulsed mode - use those caps, and a ballast resistor. For continuous operation, electric shower elements make good watercooled ballast resistors.
I'm not sure how necessary the magnet is to get _some_ output, but will probably help get output at lower currents. I've run a similar sized tube by simply connecting the magnet in series with the anode. I'd expect to need a few amps at maybe 200v to get some lasing, if the mirrors are well aligned.
What surprises me is the lack of a HV igniter module - this is the first Ar laser I've ever seen without one. The typical igniter is very similar to discharge lamp ones - spark discharge to a coil in series with the anode to produce a few kv spike. You can test by looking for a purple flash in the bore ( won't lase!). Filaments are typically run continuously, just don't run it for long without cooling. Again, this is the first Ar tube I've seen that has any more than a simple centre-tapped transformer for the filament - again maybe for stability.
The gas reservoir is to increase gas volume, to reduce the effect of temperature on pressure, and dilute any outgassing. Not sure why so many tubes on it though - maybe a standard part - some lasers have top-up valves to adjust gas pressure.
BTW not good to let coolant leak on floor with cat around- could be antifreeze or other nasties in it.
Thanks! I'll give it a try, I think I can cobble together enough battery chargers to get 200V at 20A or so, and the ignitor from the cinema projector should be just the ticket. I'm puzzled by the lack of ignitor too. I wonder if it's some clever tube design, or (a bit far fetched) a radioactive ionizer in the tube. Would expect a radiation warning in that case.
Good point about the coolant. It said "use deionized water only" so I didn't think much of it, but who knows what was actually in there.
Vancouver, are you speaking of Washington? Or B.C?
tesla500 watch yourself on coolent and animals. its probably denatured for one reason or annother
For the igniter, look at the schematics at around 15:49 you see these big triacs and that coil around the tube...that could be a nice igniter if the sequence is carefully chosen the coil would produce enough voltage to ignite the tube...
Nope, the Novus has a 600volt "soft" DC that sits across the tube when the system is on to help it start. Otherwise it's just the regular HVPS that starts it. The power supply was pretty special, but sometimes it liked to blow those big FETS up in the power supply, rather dramatically from time to time. There was a fix for that.
hi tesla500 I was a laser tech for many years working with 25 watt watercooled largeframe argon lasers in touring shows.you need at least 220 volts dc on the anode and cathode.with at least 10 amps to get it to start.then you need a filament transformer that you have. now that winding around the tube is a highfield magnet.you can run without it but you will loose power ...then with filament first let heat for 2 min then hit it with 220 dc but now comes tricky part you need to give it a high voltage start up hit .then you have to tune it for power.miss the old days...and that tube on the side is a auto gas fill ..I will do a video of one of my watercooled argon lasers its a 5 watt American 909 that has not run in 20 years.been way to long ....by the way great videos.
Hi. I had one of those along with a medical krypton unit I tore down. The Krypton had a Y shaped High reflector and a standard Output coupler . The Argon was that tube in your video. That tube is designed for low duty cycles -not long runs at high power.-. I scrapped the power supply and gave the tube and resonator to a friend in the lasershow biz. fun toys!.
brilliant teardown, always good when the left over scraps pay for the salvaged bits!
I think for me personally my favorite takeaway from this teardown is that fancy rolling case for everything. Would make a really sexy little server box.. I'm kinda jealous
Is that to play with the cat?
Ok, watched the rest of it. The filament needs to be hot all the time. It's a Barium/Strontium oxide low work function coated tungsten filament cathode that provides all of the current for the axial discharge. Tube voltage is ~ a couple hundred volts, there's probably a pre-ionization circuit in there to reduce the cathode sputtering load. The argon gas is sputter pumped away during normal operation which is why there's a connected static gas store along side the tube. The refill procedure is very specific because if the resonator tube is under or over filled, it will not strike and lase within spec. At some point there was a solenoid fill valve between static store and resonator, although am not sure what this specific tube needs. Bummer that you completely dismantled it. Argon lasers are finicky. One does not just slap some power supply on it and make it lase. That electro -magnet supplements the tungsten-beryllium plasma limiters in the core of the resonator (the sources for the sputter pumping of the argon). It's a delicate balance of current density, gas fill/number density and brewster windowed optical resonator. If it's used for medical, it has beam sampling for constant power feedback control. There will be feedbacks all over the place such that a patient can never get too much light. Less conservatively, the patient will not get too little light either. Sick fact, doctors are not scientists. They are not trained in logic, deduction, inference not any kind of problem solving. They're box-checkers and money makers. Sorry so cynical, but I calls it as I sees it.
Many hospitals chuck their lasers before a tech even has a chance to do something like recharge the gain medium. The failures are typically simple. Doctors have no clue.
Filament transformer is always on. 180V would be my guess for tube voltage. Starting pulse needs to be several kV, maybe a little less than 10? Electromagnet current isn't critical - it's there to improve efficiency and reduce bore wear I believe. So you could try a few different levels without damaging things. You can ask the good folks at photonlexicon forums that will certainly know more.
Wow, the precision of these is amazing.
The four fingers on the end of the gas reservoir contain small glass ampules of gas that are crushed to recharge the tube as pressure drops from use
Ahh, I had read about a method to add internally stored gas, I was wondering how that was done. Thanks! How would you know gas needed to be added? Laser output low? Tube voltage?
Yeah tube voltage drops as the tube is used. No idea what percent of normal would be considered needing a fill, that's probably secret sauce for each unique model of laser
I just found my new favourite channel on RUclips!
Keep doing this awesome videos buddy.
Best wishes from spanish sub. :D
Hola, qué haces por acá?
I love your passion and what you're doing with your videos. Really fascinating stuff!
They don't make them like they used to!!! So well designed and built! It's such a shame you couldn't get it running or at least find out what was wrong with it :'(
best teardown in history
oh i love it when you do videos about lasers....i'm tempted to buy that laser from you whenever your done with it, but i think its one of those instances where i should just stop myself. after all i still need to fix the last laser i bought from ya. hahaha :D
"Low efficiency" is the understatement of the year... :) 10kW in and 2.5W out makes for 0.025% efficiency :)
I really want to see the laser tube running, but it's really not easy to run the tube without the original PSU, awesome teardown, thumbs up !! Alex
There is something inherently fascinating about these laser units. Wish I could help but I have never had the opportunity to get hands on with any laser tubes.
Medical appliances are supposed to have a lower leakage current compared to consumer devices.can't remember the numbers,that would explain all the grounding
that filament transformer appears to be a ferroresonant voltage regulating one. the output of the transformer should be the same voltage for a fairly wide range of input AC voltage, something like 100-140VAC range.
Thanks for explaining the power supply. I have an i70 and I was always wondering how the exciter works. I was expecting some linear portion in the power supply but I always thought that this would require a lot more than just 4 transistors.
Unbelievable how many power supplies were inside that cabinet.
Kind of a shame the laser power control is so integrated into the main CPU board, would be a major project just the power it up.
The problem with diodes is that you wont find a 2.5w 488nm unit, however you can find the 450nm in many tens of watts.
I got motion sickness right about 7:35. Might I suggest setting up a tripod while doing teardowns?
your teardowns got my sub, keep them coming
Nice teardown, The problem in England is if a scrap yard had one and you showed any interest in it, the owner immediately thinks it worth a million pounds.
Always open with, "I think my brother-in-law is into those; what's it worth?"
That's pretty much everywhere,you really have to know someone.
It probably was worth a million pands in 1993.
I find it hard to understand how multiple machines like this ended up in a scrap yard though..........I hate to be the one that says it,but chances are someone somewhere could have fixed one or two and put them to good use someplace.
@@southjerseysound7340 They were too old to repair. New model will be smaller, cheaper, less power, fresh guarantee and the hospital can lease it via the current account instead of having to calculate depreciation for an old asset and purchase a new maintenance contract for the vintage gear. The manufacturer would be very hard pressed to keep all spares in stock on old machines lie that.
first thought on the error code. argon lasers need periodic charging from the attached static reservoir. yes, it could be something else, but after 30s POST, the hot cathode is checked, and there's a built-in ion pressure gauge. there's a procedure for recharging the resonator that (i felt) required strict adherence to the fill procedure. i'm watching further to see what the diagnosis is.
Ion lasers tend to drive the gas molecules right into the glass of the tube, where they remain, lowering the gas pressure. Hence the gas reservoir. The problem is if the tube is not used for an extended period of time those gas molecules migrate back out and raise the tube pressure to the point that the laser won't work. So unless it is equipped with an ion pump there isn't much you can do except send it to a tube refurb place. Not sure if they exist anymore.
I'm guessing the dr's names on the label with which foot was put on there so when the nurses are setting up for surgery before the doctors get there they put the foot pedal on the correct side of the operating table depending on which Doctor was operating that day. (I'm a nurse)
I used to occasionally work on this model many years ago . The E2 error code was I beleive a code to let you know your laser is not connectect to the Slit lamp or LIO.
the filament on argon lasers is always on and is usually around 3v or so but at 30-50 amps
Well, at least you got some cool parts out of it. It's too bad it wouldn't fire up though.
It did come in a nice looking case. Should build a big cap bank in there to run a portable can crusher or coil gun or something.
I'm guessing the D-Sub connectors between boards are so the control panel can be mounted remotely from the laser unit.
The "filament winding" looks a lot like a ballast for a HPS or halide light
The speckle pattern indicates it's a multi-mode fiber and comes from interference between the different modes. You probably already knew that.
one more thing water...it only flows around the tube so no voltage problem...just keep water flowing all the time ....the filament is on ...and 5 min after shut off have fun and that laser will have 7 lines of color from green to blue..with the right optics.
You should attach a gun stock to the big laser to make a cool wall hanger laser riffle.
Pretty sure the transformer is the trigger transformer. The filament transformer shoulf have much fewer windings. That capacitor form an LC resonator with the secondary and should generate a few kV at 10+kHz to strike the tube.
"some sort of resonance thing is actually the 5-10kv start pulse generator i believe
maybe make a nice audio amplifier with some of the leftovers ?
Mike from mikes electrics stuff will be very interested in the laser tubes, If you want to run it talk to him I always thought the focusing coil was in series with the b+ going to the tube.
I bet those 2N3055 pass transistors have popped. They are prone to voltage spikes. Tube voltage will be 25KV
That simply makes no sense to me how this machine needs all that power input for such a minimal output and that laser tube looks more like a 50 watt cutting laser tube. And all that electronic mumbo jumbo for 2.5 watts laser...amazing. BTW need my eyes fixed can I trust that you have a steady hand and can get er running?
Nice teardown and shirt. :P
Is that one more teardown candidate I see on the left at the beginning of the video ?
Yep, a CO2 laser
Large inductor (and one diode) is for passive PFC
I would have got a try to repair this machine before the teardown :/ But still really great video !
You might try a decent powered neon sign transformer. I'd run it in series with a diode as that's probably a DC laser tube. You'll definitely want to run the water loop too as those tubes get pretty hot. NSTs are cheap enough and you can probably get some power ratings off the original power supply if you have anything to measure inductance. Of course that said, you could just use your multimeter on the output stage if it's rated high enough. You could use a variac on the input to lower that if needed for measuring. I'm sort of into plasma physics...
That's a lot of electrons to get 2.5w of photons.
I'd believe 25w for an argon/ion laser, but 2.5w?
The resulting beam had better be incredibly stable and coherent, or I'd be looking for something like a space heater stuffed in there somewhere (and I'm not talking about the tube's filament!).
I'd bet these got replaced by something that either uses the same kind of tube with a switch-mode power supply, or they went with a diode-laser source that fits on a counter and draws maybe 5A 120v (or 2.5A 240v) maximum.
Diode lasers have gotten much better than they were in the early-mid 90's.
However, for all the criticism I have for it, it's likely near the best we could do at the time, and it's certainly Old School Cool.
Aren't most medical lasers now simple YAGs?
gas ion lasers is one of the worst tube mediums en.wikipedia.org/wiki/Ion_laser#Argon_laser 1050W to run a 130mW laser
It shouldn't quite be that bad, 1W in the entertainment Ar/Kr range was sub-kilowatt. Medical lasers typically have some very special requirements though. It might also include large system losses.
Awesome videos!
couldn’t help but notice the wonderbolt academy shirt, wish i had one now ^_^
I don't know what the main board (and a few of the others) had to do, but judging from the ICs you can see there you most probably could replace at least half of it by a single 5$ microcontroller nowadays.
very nice video, this had probably taken some time to explain edit and all...i would not bother to fire up that laser...so much work and energy for 2.5W beam
I would be interested in the argon / He Ne beam splitter if its still available.
I have one of those PowerOne 12V supplies running a T-amp.
This is right up photonicinduction's alley.
I wonder if that little HeNe caused the error codes? What a shame it would be if the whole reason the machine failed to power up was because of the failed aiming laser power supply.
To power on that HeNe laser the yellow wire is an enable line. Play with Junk also did a teardown of this same laser.
I never knew you were a fellow lower mainlander. What scrapyard did you find these goodies at?
Interested as well.
is this Laser from Germany? because here is 230v 50Hz normal!
The King
Might be. Coherent also produces in Germany apart from the US where they originate.
Almost traded a guy some milling equipment for one of these a year or so ago. Kind of wish I'd gone through with it, though I just don't have the space for another piece of equipment lying around the house.
That is a simple repair.
Please enlighten us as to what the repair would have been
i wouldn't mine that fan and rad for some of my projects
Why would they use something inefficient as this instead of like a co2 laser
The specific wavelengths are needed for eye surgery. Certain parts of the eye absorb the Argon green line, and other parts the blue line. At the time this was made (1993), high power green and blue diode lasers were unavailable, so inefficient Argon lasers were the only way to do it.
I don't mean to alarm you but your feather duster is alive and moving.
I don't get why it takes so much power for a 2.5W laser when you can get laser pointers that have even more than that and run on AA batteries so what makes this laser so special (probably some experts are cringing now because of my comparison and poor understanding :D )
Dustin Heeger the beam quality and spatial mode is important in surgery use ;) laser diodes have poor beam quality and the mode is changing with time and température.
I keep my lexel 85 ion laser even if it's heavy and consume 16amps@230v (and tap water flow) for only....900mW of light power xD (some pictures are on Flickr)
thanks
awesome!
the scrap yard just lets you take it or you have to buy it from em?
Had to buy it, they wanted $75 each (value assuming the entire thing was aluminum), I negotiated down to $100 for two
OMFG I NEED THESE CAPACITORS *-*
To bad i live in Germany, i would love to own that tube; Nice video :D
How much for the tube?
Also does anyone have any idea of what those error codes meant?? Am very curious.
the cat doesn't understand why you think the laser is more interesting than a cat
50$ for all this?!?! WOW that stuff was super cheap
So that thing takes in nearly 10kW to produce a 2.5W LASER? Daymn!....
yup. those things are crazy inefficient. I was on an excursion in a research facility once, they had insane 60+ kW setups that barely could light a match. No memories of the type, but those also were some gas lasers.
haha your kitty looks *just* like my kitty! :D
Was that a SO-DIMM just sitting under the rad? Haha
Want those Caps so bad...
How would I send stuff to you to drop in the mower?
Send me an email at tesla500@hotmail.com
Hey, that's a lot of things to recycle!
i would of fixed it before Chopin it apart..
Shaky-vision = BARF!
Please set the camera down!
what is your twitter?
twitter.com/tesla5hundred
Start a thread on photonlexicon.com forums. Someone their will definitely know about it. They might really want the tube too
there and laserpointerforums.com lot of us have restored argons, just nothing this big personally.
meow
I shouldn't watch these during November.
All I got to say is, please paint or epoxy your garage floor if you are going to video on it lol
Oh BTW andersonlasers.com would be a good place to find some Laser parts to buy or sell..
May, might, probably, maybe….. Americans…. Unbelievable!
"+ S" "- S"
Can u remove my tattos please :)
You have not a clue.