I just acquired this lab laser ca 1989, trying to resuscitate it. It looks real clean but it would sure help to have a circuit diagram and Ideally a manual.
Is anyone familiar this model?
TIA
I just acquired this lab laser ca 1989, trying to resuscitate it. It looks real clean but it would sure help to have a circuit diagram and Ideally a manual.
Is anyone familiar this model?
TIA
I'm sure Planters, our dye laser specialist, will be along shortly.
Where are you located? We may have a member who can help...
Steve
Qui habet Christos, habet Vitam!
I should have rented the space under my name for advertising.
When I still could have...
Thanks Mixed...
I'm in the Berkeley, S.F. Bay area.
Dan
I'd love to dig into this laser. It's a coaxial lamp pumped model I'll wager and so low rep rate. I'm impressed with the volume of the head for such a small dye cell. What is the capacitor rating V and uF? Is there a SG or a thyratron? Describe the dye reservoir and any residual dye. The dye circulation pump capacity will give a rep rate estimate, as will the J/sec of the power supply. Ultimately, these things are so simple you will be able to get it to work even if you obtain parts from the hardware store.
The prism tuner is nice and will be fun to work with. For an initial run I would consider using a plano HR for set up. It looks like a spark gap switch. With the SG and cap shorted, use a HV, low current source to excite the lamp. Do you get a spyder web of blue arcs that indicate an intact xenon fill? That is one hell of a capacitor. Even if the lamp is contaminated, you will be able to convert to an ablating wall air lamp and produce even shorter pulses. You will probably not want to use a NST because neither lead will be grounded. There are low cost alternatives that will work better depending on the average power needed. The dye pump/radiator/storage may prove to be your most challenging issue. I'll think about that.
Thanks for the tips. I will hack at it and see what lights up. I don't think I can get to the annular flash tube without major stripping of the shielding (see pic) Does that appear to be the shrink covered gas pinchoff?
But the HV test may show the arcs inside, looking in the end (sans lasing, of course).
Right, that is what I would do. I think that is the pinch off. These coaxial lamp systems are going to be challenging and that is why so many flash lamp dyes went to imaging or close coupledBut the HV test may show the arcs inside, looking in the end (sans lasing, of course).
linear lamps to facilitate changing-out the lamps. This laser was designed back in the era when speed, speed speed was everything. Based on work presented by F.J Durate it is now clearer that peak power rules. I have discovered this for myself the hard way. Laser pumped dyes have conversion efficiencies that can exceed 50% while flash lamp pumped systems struggle to exceed 1%. A typical xenon flash lamp can convert 50% of the capacitor input to light and around 25% at wavelengths blue of the common dyes and this is potentially in the absorption range. The huge drop in efficiency from there can be attributed to peak power. A laser pump can generate 1-2MW/cm2 of fluence on the dye cell while 20kW/cm2 is around the max for a flash lamp. If you increase the power to the xenon lamp the laser power and efficiency will rise quickly. Before the lamp simply explodes the output begins to saturate and the pulse duration begins to lengthen.
The solution is to use a low pressure, ablating wall lamp. Xenon's efficiency comes from the fact that it is a line emitter and its lines are well located in the blue green part of the spectrum. As the lamp is driven ever harder the xenon's emission becomes swamped by random thermal emission, but the high initial pressures in the lamp increase the impact (momemtum) on the envelope (leading to an explosion) and the impedance of the circuit (which extends the pulse). If the lamp no longer holds the xenon, you can use air or if you PM me I'll tell you about an even better gas, but these would require that you change over to a low pressure flowing system rather than a sealed tube.
Fascinating thread,
@ planters "an even better gas," (than Xenon?) & " low pressure flowing system "....(to supply a friendly arc environment) ..... reminds me of my old DIY CO2 laser with it's enormous gas bottle and discreetly hidden vacuum pump...... I am all ears !
@ manyhats ....very best of luck with this..................... it's really great to see "techno-archeology" is thriving on t'other side of pond!
Keep the pics rolling pls
Cheers