Say hello to my little friend Hi! Yes, it's tear down time again and this one's been a long time coming. Get it? I'm here all week. It's a 10 watt Argon Ion laser we're going to tear down today. Absolutely fantastic.

And it's courtesy of Daryl Tewksbury, who worked for Laservision Australia. You might see some of their stuff behind me. I'll link in some demos down below. so this is where they project on.

Like the side of buildings. You've seen those sort of things like the contour maps onto like Sydney Opera House or something like that. Or they might project them onto gigantic sheets of water in some big fountain thing. You know, these massive outdoor laser displays.

Laser Vision Australia were one of the, uh, you know, the world's biggest uh. they would produce some of the world's biggest laser uh displays all over the world. So Daryl actually, uh, designed, uh, most of the control systems for Laser Vision Australia. And we've done a one-hour amp hour episode podcast linked down below with Daryl talking about the design of all these systems.

They're absolutely fantastic. Highly recommend you watch that down below. Anyway, this is a coherent Skylight 300c Innova technology 10 watt Argon Ion laser. Oh man, what a bad boy.

42 kilos worth water cooled. It's got this huge umbilical uh cable with you know, like it takes a lot of power. These this is a 10 watt visible laser output, but the power supply was kilowatts. So yeah, there's a bit of waste heat inside this bad boy that need to come out so it's got pipes on it for water cooling and control and all sorts of stuff.

And I believe this is a single line version. I.e like just one color based on the serial number. It's got Sl on the end. I assume it's single line.

uh. but you can also get these in multi-line versions as well. So they generate like different colors, like different parts of the spectrum at the same time. and you can separate those colors if you need to.

using a polychromatic Acousto optical modulator. Say that one three times quickly. But oh, this is absolutely phenomenal. They don't.

They might still make these because the output of these is extremely pure compared to the solid state ones you get these days. Sure, a 10 watt lasers? Meh. It's nothing, right. You can buy them on ebay for 100 bucks, can't you or something like that, but it can't produce the quality of output that you use for these things.

Not just for outdoor displays, but for all sorts of like you know, medical and research applications and things like that. So for medical and research applications and stuff like that, you want one of these bad boys, one of these plasma argon ion lasers. Let's tear this thing down. It's going to be fun.

And yes, we have the manuals. Let's go. So that's the business end up there. It's got, uh, some big mounting bolts on it.

sort of. I think they're integral to the chassis of the thing. And there's the big connector interface with the cooling hoses and 1.2 meters long. Check this out.

Unbelievable. There's a model and serial number for those playing along at home. made in the United States of America. Now we've got our two lovely feeling controls here.

These are for what's called the high mirror assembly, which essentially this one does the horizontal and this one does the vertical. This one seems a bit busted. I'm not sure what the deal is there, but uh, yeah. um, these can adjust.

Basically it looks like they adjust the output or something. Maybe we'll physically we should be able to physically see these when we open it up. And if you're wondering why the cables and the connectors have to be so bulky like this, well take a look at the tear down of the power supply. This has a maximum tube current of 60 amps.

This thing requires 24 kilowatts maximum for this whole head assembly. 24 kilowatts for 10 watts maximum laser output. Yeah, the rest is waste heat and that's why it needs this cooling hose here. And this is just a D25 control interface like that'll do you know, modulation, something like that, and various control and measurement.

Uh, signals on a Molex connector there. So it's a beast. And here's the business end and this has a screw-off bit. Not sure if that does anything or not, but anyway, it's got a Class 4 warning sticker on for those playing along at home and there's an aperture control on the top.

You can close and open that and adjust it. Ah, goes all the way to 11.. All right, let's open this bad boy up. and what we're going to see in here is basically all it is.

that its simplest form is a like a meter-long plasma tube in the thing with a giant electro magnet on it and some feedback stuff and just some optics at the front. There's more, of course physics and science going on there, but that's essentially what it is. a giant electro magnet on a plasma tube that has some 700 amps per square centimeter for those playing along at home. So let's have a squeeze.

Oh oh geez, that's not very exciting. Isn't it going to take the protective cover off? So here we go. let's lift this off danger. High Voltage under this cover? Look at that.

Oh, it's a Bobby Dazzler. Oh, something. fell down. All right.

So here goes my basic non-physicist uh description of how one of these Argon or Noble Gas lasers work could be Argon, Krypton. Uh, they all work very similar. The basic principle of operation is this is the output and this is the dangerous output end. That is the rear reflector up there.

and that's called the high reflector. There's a ceramic tube inside there, completely sealed. It's got a 100 reflector at one end, the high reflector and it's got like a maybe in the order of 99 reflector at the other end, and inside is the gas which you have to ionize and that turns into a plasma. And to keep the plasma confined, you need a huge electromagnet on here.

and then you've got a cathode filament up at this end and you'll have an anode, uh, filament up this end. This is the anode wire here, the red one and so then you'll create a current through the tube which is then ionized and there's a starter in there as well, so you provide. When you turn it on, you provide a brief high voltage surge to actually, um, start the thing up to get the ions flowing in there, and once you do that, then the magnet contains it in there. and then the light bounces back and forth back and forth, back and forth.

and about one percent of it, a tiny fraction of it goes out the front window like that. And that's basically how any of these ion lasers work. You just amplify the light in there by just bouncing it back and forth back and forth and then containing it with that magnetic field. Containing the plasma inside and then a little bit sneaks out the end because if you have too much sneaking out the end here, then well, it's not going to amplify enough and the whole system just doesn't work.

Because Laser of course stands for light amplification by stimulated emission of radiation. So the light needs to amplify by bouncing around there and being contained. And that's why this thing takes tens of kilowatts to give you 10 watts output. Yeah, there's more efficient ones these days solid state ones, but oh, these are beautiful.

And the output mirror here? Uh, it's actually, uh, not inside the sealed tube as we'll see in a minute. It's actually right at the front here, right outside. And they do some tricky business out here. And the end of the seal tube actually ends here and you can do that, uh, similarly on the other end as well.

But anyway, they have to be perfectly aligned in there for the air light to amplify and boost up to give you, uh, the high power output. Otherwise, it's going to be pretty piss weak. And of course, you want a constant output power of the laser. So what they do is tap off a bit of uh, light from the output uh here.

and they feed that back and that actually controls the system and it's a servo error, uh, control thing. and it regulates the output power. Now there's three long metal bars going the entire length of this thing here here, and also one down the bottom at the back there. And these aren't just any ordinary metal.

these are what's called super Inva and this is 32 nickel, 5 percent Cobalt, and then other elements of iron uh, copper, aluminium, and manganese as well. And these are used in precision optical systems. You know those whiz-bang optical uh benches that you you know, see and you know have a bench set up all the holes in all the optical mirrors and everything and that's this is a typical material that will be used in those because they've got incredibly low thermal expansion at you know, nominal uh, room temperatures like this. So because you have to align all of the precision mirrors in these and everything else.

and that's what these knobs here do. and you'll see that this here just changes the angle of this very, very slightly. And it doesn't take much for you to change the output power of this thing based on the angles of the mirrors. And for those technically minded, just 10 micro radians of angle out on the mirror that's part of the resonant cavity in here is enough to, uh, measurably change the output power of this thing.

So yeah, it's critically important. And also, when you've got uh, you know, pumps and everything else like water pumps, there's water pumping through this, so any like vibration and everything else that can affect your uh, the performance of the Uh cavity, the resonant cavity as well, and hence the output power. so you know you've got to be incredibly careful. Now there's nothing you can't fix with a Dremel.

So got those screws off and ta-da I'm actually surprised to see a board in there. I didn't think that this actually had anything. I think I thought it did all the uh, sensing and um, control other stuff in the power supply head. but nope, there's some serious stuff going on in there.

Check that out and only all the high voltage cabling. All the high voltage high current stuff is all running under there. Nice. Right out to the end.

like that. so they just got them popping up. But yeah, it's got some serious controller monitoring in there. Yeah, trying not to blow up your oscilloscope? There you go for you Adc196 fanboys.

Um, that's a fair bit of grunt in there. Got a socketed E-squared prom there? of course. Our Rom is down here like this and uh oh, we're gonna have some sensing stuff. There's an Analog Devices jobby Linear Technologies jobby 1014 there that's a quad precision Op amp and well, yeah, is that a 324? Is it? Yeah.

So we've got some jelly bean stuff in there as well. and then some regulation and whatnot. So that would be doing. um, all of the uh, safety and control you know, safety cutouts and control stuff for the tube.

But interestingly I believe this here is the uh laser output photodiode sensor because that that taps off they've got that's actually rigid. That's not wire that's actually a rigid pipe. Why it's got that kink in there. I'm not actually.

uh sure. But yeah, that does Tap off here, should flip this up and show you. and that actually goes through to here like this. So we've got this penetrator here, but that wiring seems to actually bypass this control board and go back to the main power supply control unit.

So yeah, there's none of that um, sensing actually done with this board here. So let's actually have a look at the signals that it is monitoring. There's this cable at this end that goes to this box which is bolted on the bottom, which actually I have to flip it up, but that goes that's actually tapped off the anode isolator which then goes into this board here, but there's not much else. There's this connector here, and there's two others here and that's all she wrote.

And then there's just an output uh, like D25 coming off there like that and that's going to presumably match the D25 at the other end of the cable there. So from what I gather, all that board actually taps off is something on the output here. We've got some micro switches on the top here just to uh like in take case to take the uh top off. There's another one right on the other end as well.

So you know once you cut the take the top off, it'll like cut all output and whatnot. But as I said, this must be the photo diode which taps off the output. And sure enough, here's the block diagram of the whole thing that actually shows. Uh, that? that taps off Immediately back to the power supply.

So they've got this rigid optical thing. Is it like a rigid fiber or something? I'm not sure. leave it in the comments down below, but it looks like it's got like a copper outer sheath or something. But it's got to be uh, tapping off the optical as part of the resonator in there.

So it's tapping that off. and uh, detecting that why it actually has this tube on the end of it. I'm not actually sure what the deal is there. If you do know laser experts, leave it in the comments down below.

Okay, so let's follow the money on these big bad boys here and see what's what. Our black and our white wires here these are for the uh, filament. Uh, the heater filament itself. Um, and the red is the anode.

Uh, green will be earth. So if we actually follow those over to here, we'll see that. the black and the white wire. You can't see that, but the white wires were over the other side.

there. There it is there. and they come in to these uh, high voltage penetrators here and you'll see that, Um, they. I think they're ceramic.

Kind of feels ceramic-y That's what you expect for like a high-voltage uh penetrator. And of course, this entire thing is uh, hermetically sealed. Of course, because it works at a vacuum or low pressure or something like that, of course. And if you let all the vacuumy out, then your laser don't work so good anymore.

Now check this out because this is actually quite, uh, fascinating. There's actually nothing in there. look ma, no hands, look nothing. We've got an output, uh window here and this is like a but I don't know what sort of you know, a quartz or something, uh, window on there and this is called the Brewster window.

So it's named after Brewster. and uh, this has to do with what's called Brewster's Angle and this angle here is, uh, 55.5 degrees. No coincidence, I'm sure 55.5 degrees. And what that does is that actually allows polarized light to transmit through with basically almost practically zero internal, uh, reflection.

So I don't know all the physicists out there in the comments going nuts about, uh, Brewster's angle and polarized light and all that sort of magic. But basically, yeah, that's a special doo dab window at a special doodad angle to let all the polarized goodness out and what this actual metal thing here is doing. I don't know, like there's an o-ring on the outside, but what that's doing, it's not like you know, because this is going to be hermetically sealed as well to keep the vacuum goodness in there. And this is.

this is actually a ceramic, um, internal, uh tube which goes all the way through. So that's that's all ceramic-y so it doesn't seal it so I don't know. There's no power loss there. It almost looks heat-sink finish so I don't know.

Leave it in the comments why? that's a thing and of course it. Look, there's nothing on the other side. I can just take that off. And then we just got the metal tube going out there and this plastic dude that just goes on there like that and well, I don't know.

It doesn't do anything. So um, yeah, um, Beulah Bueller. Anyway, they do actually have our four terminal, uh, sensing wires. You see the wire coming off here.

there's a white one, uh, same on the other side and that goes directly back, uh to the power supply. and that allows them to sense, uh, the voltage directly across here and know the loss across the cable and everything else. You can see how beefy that cable is. I mean, that's just.

uh yeah. There's a lot of copper goodness in there. And they've got, um, two fuses in there. Not, these are not fuses for the main filament line.

These are actually um, fuses for the feedback. Um, sense line. So yeah, I guess they deemed that that was, uh, important enough that they needed. Um.

fuses in the feedback, but not the filament. Um, you'd waste power there. and then the big red cable in here. that is for the Uh anode and that's labeled Uh B Plus And then it goes off here.

What we've got here is a diode. If we do, we have the right direction we do. There you go, it's a diode. Yeah, so that would be a big special doodad diode in there high voltage jobby.

and you can see that there's a red wire tapping off there and that goes into this box down here, which I believe would be the Uh starter for this thing. so that would, um, help give it the kick required to actually start this thing off. And then the cable from this starter actually goes off to the monitoring board on the bottom. So yeah, how that all works.

They don't show you that in the block diagram, but that's what it's doing. and then your anode wire from the other side of the diode here goes across here and tada. It just buggers off down into the tube there somewhere. So I'm not sure how that works internally, how it penetrates and and this danger.

high voltage? Well, that just moves. Um, so I'm not sure what that's that's just some outer sheath to physically protect as like a high voltage arcing over perhaps I would assume. Um, and this nylon Here, this just spins around and does nothing. So these are your filament connections there here and these go through to your cathode filament.

which is, I don't know in here somewhere I don't know exactly what and you can probably see these wires coming up here. These actually come from a base connector down the bottom, there and there for your electromagnet which is in this top outer case in here. So the tube discharge current basically comes uh, through the anode here and that goes through a big diode there and then into uh, the anode at this end and then the discharge current is inside the ceramic tube inside. it's our self, which you can see at the end and then it comes from the uh, filament end of this thing.

So that's where all that's about a 60 amp discharge current inside this thing. I don't know how much the electromagnet on here takes though, and that's where all the power's being dissipated. And that is why these tubes here exist. Because these are actually water pipes and this whole outer case in here containing, um, like the water cooling channel.

So this is where they have to get out like the tens of kilowatts out of this thing. So you know you've got to pump a high volume of fluid through there just to get all the power out of here all the waste heat out. Otherwise, yeah, you could cook a couple of snags on there, no worries and tied into there. That's a bit old-school We've got a, uh, a thermal cut out switch there, which um, obviously that just goes back to the logic board I think, or does it run back to the main power supply? You would think that you know if you get an over temperature so this is just a mechanical uh cutoff in there if it just gets, uh, too hot.

the little strip either you know, breaks the circuit or makes it and that's it. It cuts it off and the water cooling is rather interesting. Let's I don't know which one's in or which one's out, but let's just assume this one's in here. Then it pumps it into here and then it goes into like I'll call that like the inner casing I guess.

So it actually goes into this outer ring and that's where that temperature sensor there is. So the water flows into here into the inner casing and then it'll flow all the way through the inner casing I would guess. and then you can see at there's another tube that comes out here like this and this goes over to here to I guess the outer casing for want of a better word and then out here and then back and that goes up the cable all the way back to the power supply and then the power supply which we've looked at in the previous, uh, tear down. We've got the heat exchanger here to get all the heat out of the power trenny array over here.

So yeah, it's remarkable. And somewhere in here there's actually a catalyst which basically absorbs any ozone produced because the uh, you'll get a buildup of ozone within the uh laser cavity and that can, uh, you know, degrade uh your laser over time. So yeah, I I so I guess they've got like a finite life on those things and the output power will drop with time. That's probably one of the reasons why, and that's caused by a photochemical conversion inside which converts the oxygen into ozones.

So yeah, this is designed to handle that, but other laser systems that don't like handle that automatically with a like a building catalyst to absorb it. They need like purging of the ozone periodically. And if we take off the end here, we can see that we've got three doodads here. This is the laser out Butch.

As I said, I don't know what that does and probably just nothing. I don't know. you can attach uh things to it or whatnot. But anyway, these two things here.

These are interesting. These are actually I've taken the screw off there. These are actually our two electro uh magnets and these are actually um aligned at a perpendicular. So these two uh electromagnetic actuators Here these are actually are dithered at a 30 Hertz frequency and this is part of the power track system that uh, coherent caller.

This is their Uh technology for actually reducing the output uh noise of the laser. essentially. so they differ these at 30 hertz and it looks like they got another Um sensor here. which then all of this goes back to the control board underneath.

and it looks like that control board locally does all of the uh, real-time processing required and these actually dither, uh, the output mirror in it, which will be directly inside there. I think if I took that off there, we might be able to see the output mirror and that just minutely dithers that mirror And by tracking the phase and the coherence and whatnot, Um, you're able to actually, um, sort of like dither that mirror and sort of like Elim will not eliminate, but uh, lower the output noise of the laser. And that's one of the, uh, beautiful things about these, which you don't get in like your cheap ass semiconductor lasers. You know you hundred, what job is you buy on ebay for a hundred bucks or something, right? It's it's.

got nothing like this. They're no good like they might, they might be good for a laser show or something like that, but these have real scientific um, and you know, engineering industrial uses. Uh, for like, you know, all sorts of research applications and stuff like that where you really need a very accurate, coherent, low noise laser source at high power and that's what this thing does. So this is like, yeah, and output mirror feedback mechanism.

That's very cool. I might take that off and see if we can see in there. There you go, check that out, that's the sensor. They've just got a little angled uh, window down in there which just deflects some of the output down into this sensor here so that would be fed back.

Not sure what type of sensors in there is some sort of you know, photo diet or something like that and then the amplitude of that will be fed back to the servo control for the two electro magnets up here which then do the window. Oh, I can take that out. If I hold that output window up to my Led lights up there you can see which is all color balanced. My cameras are color balanced for 5000 kelvin which these are outputting.

You can see how it appears a different color so that window certainly is, uh, is certainly filtered somehow. But anyway, that is being controlled by the electromagnets here and here, so they're able to like just dither that window a little bit. So how that's actually mounted in there I don't know. Uh, I that looks like a sealed assembly certainly does look very pretty down in there.

I'm sure if that's showing up on camera, but shiny shiny equals expensive. Oh no, check it out. It did come out. look, I just I just pulled it out.

so that's how it's being mounted in there. Wow, It's just like I thought I expected something a bit fancier than that. A bit of crimp in there to hold it in place, but obviously the uh, electromagnets can affect that somehow. Just like it's absolutely my newt, it affects it.

I'm absolute mind new to mount. Let us know in the comments down below if you know exactly because it doesn't tell me. but yeah, there you go. There's your window.

Oh yeah, you can see the color change. Neat, huh? What's that worth? Oh, there you go. She's all coming apart. Now there's your uh, output window that uh, directs the light down into the output sensor and there you go.

That just all slides in there so that all just comes off like that or expected a bit more precision. I know you want to see the aperture. So there you go. I'm opening and closing.

Hopefully you can see that window shut in there as I open. and that's one aperture of one. And yeah, they're physically different apertures. There you go.

I'm sure they're getting slightly bigger, slightly bigger. Eight, Nine, Ten all the way to Eleven. Oh, it's very, very special because if you can see, yeah, the numbers all go to eleven, look right across the board. Eleven, Eleven, and mostly eleven.

Why don't you just make 10 louder and make 10 be the top number and make that a little louder. These go to 11.. And here's the other mirror at the other end of the ceramic tube. So this is the ascend the cable side and you can probably yeah, you can probably just see some reflection in the mirror.

there. you might even be able to see the camera or something like that. but that's the end of the uh, That's once again, the hermetically sealed end of the uh, ceramic tube. So that's just what's uh, behind the metal cap on the end.

It's just the end of the rear mirror there. So there you go. I hope you enjoyed that tear down as much as I did. Absolutely fascinating look inside an Argon ion laser.

As I said, this thing is like, you know, in the order of like 20 plus I kilowatts for 10 watts output. So yeah, it's a lot of waste heat and they're remarkable things. but they still have uses these days. They are not obsolete as I said for like you know, research applications for very pure laser light.

I don't believe there's probably other technologies now, but anyway, um, leave it in the comments down below if you know, but I believe these are still used for research applications and stuff. But for year for laser light shows, these are obsolete now because you can get with the you know, a couple hundred watt um, solid state lasers for you know, much much cheaper price that are much more efficient. So anyway, I think that's very cool and of course I'm available on all the alternative platforms Audience: Odyssey being the biggest one up to over 60 000 subscribers on Odyssey now. So brilliant stuff always linked down below.

So anyway if you liked it, give it a big thumbs up And as always you can discuss down below. Catch you next time.