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My notes and pics of a flashlamp-pumped solid-state laser from eBay
This laser was advertised as an Nd:YAG, made by Lumenis. It has an attached flashlamp trigger circuit board, which seems to be for series triggering. I apply 1.3 VDC to the "Molex" socket between the two green terminal blocks to fire the SCR.
The green blocks are the power connections. The trigger input is in between them.
Thinking the thin pair of wires leading from the flash chamber out to a "Molex" plug is a resistance temperature probe, I have it plugged into an Ohmeter. The resistance deceases a couple tenths of an Ohm per shot. I've indicated it on the schematic as a thermistor. Constants for the Steinhart–Hart equation were guestimated from an online calculator: a=.0017709, b=3.406e-4, and c=1.479e-7. The attached trigger board is in the red outline in this diagram.
Removing the bottom cover reveals the rod and flashlamp housing. The lamp has an overall length of ~75mm, a quartz length of ~63 mm, and an O.D. of 4 mm.
It's close to these Perkin Elmer models, so I'll assume: arc length=40mm, ID=2mm, Vmin=460, K0=25.6 Ohm-Amp, Eexp=1.96E4, Pmax=38 Watts, trigger>=16kV.
The black box is a Perkin Elmer TS-2244 Series Injection Transformer.
Which should be in this series; it's not, so I'll extrapolate.
I'll assume that the saturated inductance in mine is 70 uF, for flash duration calculations.
Trying varying amounts of series inductance in an attempt to determine the required amount for the optimum flash duration. Nd:YAG should be pumped for about 80 uS.
A Rogowski coil was placed around a high voltage lead. It's trace is on top, the beginning of which is negative and not caught here. The bottom trace is a photodiode in the beam, showing the Q-switching.
155 uH added in series with the assumed 70 uH saturation inductance of the transformer. The scope is set for 50 uS / div.
Whether I add a lot, or nothing, it doesn't seem to make any change, although occasionally I see four output pulses (20 uS / div.).
Focusing the beam with a microscope objective creates a spark in the air.
A painted object placed at the focus of a lens.
The YVO4 and KTP chip from a pointer are in the beam, producing a little green on a piece of paper.
Enclosed.
The unfocused beam striking graphite coated plastic:
Profiling Some Beam Damage
Axis 1
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