Laserbuilder's collection of gas and other lasers

[Laserbuilder]

Odd!

Oh, yes, it is very strange. On Sam's laser FAQ It is said that such voltage drop occurs when argon pressure is toooo high. I even don't know wether this head will lase for significant time.


Ok, I'll continue to post new photos of my lasers.

9)

LGI-21 Nitrogen laser. 3-5 mW of average power, 337.1 nm wavelength. Pulse power is correspondantely 3-5 kW with 10 ns duration, pulse repetition frequency can be up to 100 Hz. This is a very good example of a low pressure longitudinally excited (LE) nitrogen lasers. It is very simple and it is the first type of lasers I learnt to refurbish. One more interesting fact -- LE N2 lasers are very popular in the states of former USSR, but I don't see any made by foreign manufacturers. All N2 lasers I see in the Net or on e-bay are transversely excited. Nitrogen in this lasers gradually dies out with operation, but refurbishment is as simple as can be -- just open up the "nipple" through which the tube was vacuumed to let air in, pump it to 10-15 Torr and seal it back. Surrounding room air works very well in this laser, output power is only 20-25% lower than with pure N2. Maybe I'll start a separate topic where I'll tell in details about the process with detailed photos.

A separate pair of words I'd like to tell about the power suppky. It is very simple by design too -- A couple of doorknob capacitors is charged from a HVDC source through a bunch of resistors an then discharged on the primary winding of a big toroidal transformer through a hydrogen thyratron. Not even a Blumlein circuit. Thyratron is triggered with the help of a small circuit with two vacuum tubes.

On the photos there are different lasers of this model. The last two photos show the thyratron glow and corona on the output transformer, the pulsed voltage is 50 kV there.

 

[paul1598419]

Interesting collection, Laserbuilder. Thanks for sharing it here. I look forward to more of your lasers as you have time to post.

 

[Laserbuilder]

10)

ILGI-503 Nitrogen laser. It is the same as LGI-21 by appearance and performance, only some cosmetical restyling of the insides.

 

[Laserbuilder]

11)

GL-510 laser tube for LGI-505 laser.
This is a LE N2 laser too, but with higher output power. Rated average power is 50 mW at pulse repetition frequency 1000 Hz. Wavelength is common for N2 lasers -- 337 nm. It was scrapped with the HV power supply from ofthalmic research institute and with even the second NOS tube in a factory package. Unfortunately the complete LGI-505 laser head with the big thyratron and pulse forming network was gone, so I had to rebuild it.

It is interesting that this tube has a ceramic bore and water cooling, because it becomes hot at high PRR. The side arm with additional electrodes is for N2 regeneration.

I was very lucky to get the manual for this unit. The blue power supply only provides high voltage for the anode of the thyratron and triggering pulse for the control grid of it. It is interesting that HV is genereted with a small oil filled transformer and the operating frequency of it changes with the laser pulse frequency. It is a pulsed transformer which works like an automotive ignition coil, it is not only oil filled but with a water jacket too. The output HV pulse is then rectified with a single diode and charges a big ceramic capacitor. Than it is discharged on the primary winding of a ferrite pulse transformer through the thyratron. The HV pulse and triggering pulse are timed precisely, HV goes first, then the triggering pulse fires the thyratron. From the secondary of the ferrite transformer a 80-100 kV pulse hits the laser tube. At high PRR lasing is very bright, anything that can luminesce in UV glows blindingly! Uranium glass glow is particularly beautiful.

I had assembled the pulse forming network with the tube on the wooden base and then formed a wooden crate around it with the resonator mirrors. It lases with aligned mirrors (brightly), with a single mirror and without them (much worse). After some time I detached the thyratron from it for my CVL project, so it is not operational until I get another one.

 

[paul1598419]

Very nice find. It seems that some of your finds spent a long period of time out doors. Do you get them from a junk yard? I don't know what is usual in Ukraine. Some of the photos make me think that it was beyond repair. At least the driver/power section. Great job getting it working.

 

[RedCowboy]

Great pics, very interesting to see. :gj:

 

[diachi]

Interesting, as always.

 

[Laserbuilder]

12)

Pulsed Neon laser tube.

I made it from the LGI21 tube and it is fully compatible with LGI21 laser frame and PSU. It lases at 614 nm with 0.05 mW of average power. Anyway, it is a part of my collection too, so I post it here. More information is in this thread. http://laserpointerforums.com/f43/my-diy-orange-laser-99539.html

 

[Laserbuilder]

13)

UL-102 Copper Vapour Laser

The lasing lines are 510 nm and 578 nm with at least 3 W of output power on both of them.
UL-102 laser tube became the base of the fully homebuilt laser system. This is my most sophisticated laser project at the moment, that I'm very proud of. Full information on this unit is located in an appropriate thread http://laserpointerforums.com/f43/homebuilt-3-5w-copper-vapour-laser-system-99252.html

 

[Laserbuilder]

14)

GL-509 Carbon Monoxide (CO) laser tube for ILGN-706 laser.

Yes, this is a CO tube! Not CO2! It can lase on many IR lines in the range between 5 to 6 um with the gross output power of 15W. These lasers are very rare, they were developed for glass welding in vacuum tube technology and for surgery to replace common CO2 units but never become widespread.

This tube is filled with a complex gas mix which includes He, N2, O2, Xe, CO and may be some other gases. The performance of the tube is very sensitive to the gas mix purity and is not as forgiving as in common CO2 lasers, the CO laser cannot be "DIYed", as it needs very high vacuum pumps (turbomolecular for example), high purity gases and long training under gas discharge to exterminate all impurities in it. There are additional electrodes with getters in the side arm to make the life of the tube longer. It has a built in HR mirror but the OC is separate, I've got one in my optics box. At the OC end of the tube there is a huge Brewster window made of GaAs with BaF2 AR coating. I've got two GL-509 tubes and they are the biggest laser tubes in my collection. The length is 1.45m and the biggest diameter -- 10 cm. And it weighs 3 kg -- 3 kg of high quality glass!

 

[paul1598419]

Both #13, copper vapor laser and #14, CO laser are very impressive. I wish I had access to the tubes you seem to have no problem getting your hands on. I know many people here who would be envious of you, including myself.

 

[Laserbuilder]

15)

g-OI-8 (LTI-501) Continious Wave Nd:YAG laser and interchangeable K301 pumping chambers for it.

I'vo got three of these lasers And one of them is NOS in its factory crate. This laser model is only one among a big line of lasers made of unified components in the unified cast aluminium case with orange sides. There are a lot of modifications of them with the variety of output powers (from 0.5 to 250W) and wavelengthes (from 1.32 um to 0.266 um (fourth harmonic)). Changing the pumping chamber, optics, placing additional elements in the resonator like an acoustooptic modulator and\or a diaphragm, non-linear crystals allows to transform one laser into another using unified blocks with different partnumbers like in a LEGO toy. For example, I've got K301A and K301V (bigger ones) pumping chambers and a number of interchangeable mirrors with different RoC and transparency on 1064 nm.

This particular model (LTI-501) is 8 W 1064 nm Q-switched singlemode laser with the K301A pumping chamber for an engraver. When brand-new it comes together with a manual, safety goggles (OD6 for the ranges 680-1200 nm and OD3 for 630-680 nm), water hoses, 5 spare krypton arc lamps and some electric wires. Inside there is a pumping chamber, diafragm (absent on this picture) and an acoustooptic modulator. If the diafragm and AOM are removed - the beam becomes multimode and 20W in power with K301A chamber. It is quite enough for melting the razor blade with the focused beam. If you replace the K301A chamber with the K301V one -- you get 125W of power! And if you put the second one in line with the first -- the power doubles to 250W!!!! But, you need 9 kW of input for 2 lamps to work at the same time and VERY SEVERE water cooling. I can run only one lamp. And I don't have a correct OC mirror, so I didn't achieve 125W of power, in the best case a half of it. Still it was enough to burn through a steel can with a focused beam.

The power supply for the krypton arc lamp is very simple and I made it myself. It needs only a step-down transformer, bridge rectifier, ballast inductors and an ignition circuit.

I think it is best to show this laser at 50W in action on video.
https://youtu.be/xsPtM0ok_hU

 

[paul1598419]

Wow. Another difficult to get laser in your collection. I am so very envious. How many of these do you have?

 

[Laserbuilder]

Three at the moment.

 

[Laserbuilder]

16)

Custom built YAG laser with K301A pumping chamber.

20W multimode CW output on 1064 nm.

This is my small side-project with the K301A YAG pumping chamber. I've built it before getting LTI-501 lasers and this became my first operational YAG laser. The power supply for the lamp I've built in the boundaries of this project.

 

[Laserbuilder]

17)

Big laser ruby.

Though this is not a laser, but a laser component, it is worth showing here. This is a NOS laser ruby which is possibly designed for a laser amplifier. It has dimensions 16*300 mm, when the active part is 240 mm long. The ends are cut under Brewster angles. Compared with the ruby in my ruby laser, the colour of this crystal is more crimson than pale pink. The Chromium % is much higher here. The crystal has an individual package and a datasheet, but there is nothing useful. Neither dopant concentration nor test data, like possible output energy from XXXX J of pumping.

This crystal is for my future high energy ruby laser project, I hope that I'll achieve at least 50J of output energy. And I have a couple of 8 kJ lamps for it)))