|Triggering unit of about 30 kV
pulse lead to Marx bank generator.
||Initial voltage is about 15.5
kV, and at output it is about 30 kV. Two capacitors of 1 nF each was
charged in parallel, and when triggering pulse make spark at SG1, then
this two capacitors are connected in series producing double initial
voltage with very fast rise time.
|From Marx bank generator,
through coaxial cable, sharp pulse lead to dumper capacitor of 500 pF.
Blue dot represent place when occur corona preionization just before
main plasma discharge. When transferred voltage (or energy) from Marx
generator charge dumper capacitor, then self triggered spark gap SG2
begin charge peaker capacitor until voltage reach breakdown voltage
between laser electrodes.
||This is simplified diagram of
TEA laser setup. Initially, dumper capacitor was 500 pF, but later was
added another capacitor of same capacitance to increasing stored
energy. But I was not observe any differences. This is maybe because
Marx generator can't charge both capacitors to same voltage as only
one. This mean, that I need add more capacitance at Marx generator to
achieving more power.
||Detail of dumper capacitor and
|Laser electrode holders.
||0.9 mm distance produce more
|Marx generator below laser head.
||Marx generator pulled off.
|Plastic cover over laser channel
with input for pure nitrogen
||How looks this laser channel
plastic cover (now, distance between electrodes is 2 mm)
|Laser operate with air. Spot is
bright, but see next pictures...
||With pure Nitrogen (99.9965% of
purity) spot is much brighter.
|This is one output end without
white sparks. But plastic cover is not enough long to cover this
output, so there is still present some spark as it shown at next
||Mostly, white spark is occurred
at ends of electrodes, but sometimes it are present at middle of
electrodes, but this time laser beam is not diffused like in case of
0.9 mm space between electrodes.
|This is both equally output. At
middle of electrodes still are present white sparks, but this not make
trouble with diffusing any of outputs.
||Front end with fluorescent
plastic. Seems to me that this plastic have Rhodamine 6G inside,
because look same as dissolved R6G in alcohol. I was not yet try lase
||Another end show strange shape
of spot. I don't know why. Maybe this is because there are still
present some sparks. Or electrodes are not good aligned.
|This is spot at 3 meter
distance. You can see strange vertical lines which is usually because
this laser have low coherence.
||To confirm how "big" is laser
spot, I was use long exposure ant at least ten shots. Paper is wide 21
cm horizontally, so spot is about 10-15 cm wide. Around spot is also
strange lighting, which mean that white sparks still sometimes diffuse
output of laser beam.