Flashlamp Video

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As of now searching for a scattering light pipe the only thing I get is images of fibers bouncing the beam up and down inside of the fiber or at max a Cylindrical light pipe.
Where would I find such a scattering light pipe?

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I hate it when someone with a little inside knowledge claims a NDA. It's a bit like saying I heard a joke,but I can't tell you. In this case, I do not have any NDA, but I have some insight that the source would probably not appreciate my distributing to the world. I'll PM you with some additional detail, but the general idea is that the diode is simply a high brightness light source. The fact that it is a laser is irrelevant. Consider pumping the crystal laterally and specifying the dimensions of the crystal to match the diode bar emitter face. Then, close couple the diode bar right into the crystal without any optics at all. If you want some stand off then a high index material (diamond would be ideal) can act as a light pipe because of total internal reflection. Or, specify a glass rod externally coated to reflect 808nm as a light pipe. These are somewhat exotic items, but not crazy expensive.

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For the voltage divider you have on your capacitor, whats the value of the resistors you used?

I noticed a problem with the caps that i own and may lead to a spectacular failure, one has a rather deep dent on it, trust it at lower power but it's effectively untested at the rating of 2.5kv, the dent is almost 1cm deep, I am thinking about cutting it open, that as a last resort though

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http://www.caddock.com/Online_catalo...h_voltage.html

I picked up a few of these on eBay.

I don't know if I would cut it open. Maybe you will have to. Depending on the energy, you can measure the capacitance with most multi-meters and this should agree with the stated capacity. Also, charge it to a hundred volts or so and see how quickly it drops its voltage. If very slow, then it might be worth investigating the defect. The major risk is that the dent might provide a voltage failure point to the case at a high enough voltage and this would obviously be more than be dangerous. My approach in dealing with storage capacitors and especially with the huge ones I use now is to treat the case (even though it is designed to be dead) as if it might at any point be at the full charge voltage. This means mounting so that the case is fully isolated. I do not ground this case because the huge energies discharging through ground (were it to happen) would probably be more than interesting.

Yes please do PM it would interest me.
So the diode basically would act as a flash lamp alternative reading this at first sight.
I read before that materials like ruby require the entire crystal to be blasted so a helix lamp is in place there as if there are gaps they will absorb a big portion of the released coherent photons.
This does sound really really interesting though and I wonder what wavelengths can be created from this!

You're right about ruby. This is not true for vanadate/YAG.

No, the diode would act as a CW light source. The two philosophies are a longitudinally pumped crystal with a smooth, bell shaped, axially positioned pump spot. The thermal distortion caused by the pump heating is symmetrical and the cavity optics are designed to compensate for this. The other philosophy is to saturate the crystal with lateral pumping causing a diffuse and hopefully homogeneous thermal expansion of the crystal minimizing the optical effects on the laser beam. Axial pumping is more efficient, but the power that can be launched is more limited and more expensive/watt.

What is odd and i have never had this happen with a capacitor is the case seems to float to about half of the input voltage and both caps do it, the ones i have are made by NWL Capacitor, they are both 160mfd at 2.5kv dc, they hold 200 volts but the case does not make sense, the one with out the dented side does the same thing. with an ESR meter there is no connection to the case but that's at 2 volts. Maybe what i am seeing is a capacitive coupling to the case and not a real fault
I have not used them in about 10 years so i dont remember if they did that before, I got them as unused surplus back in 2005
I will be treating them as being a live case and isolate it. I too have always treated beasties like these as having a potentially live case, i think i am going to put plexiglass around these.

Thank you for the link to the resistors, i know i have stuff like that around but i need to find them now, mine i think are made by the same company, i had gotten them for use on a tank for a tesla coil as it uses 20 polypropylene caps

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i am going to put plexiglass around these.

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Good idea. Assuming you will take these to a little under 2,500V then you will be putting in a little under 500J assuming they fully discharge during a pulse and they probably won't let's assume 400 J. Then, with a 6mmID lamp and 150J/cc then you need 2.7cc and this gives a 10cm electrode spacing. This might seem small, but that is where the magic happens.

Thank you for the info. I also had a second question about a power supply, my glassman unit is a bit temperamental at lower voltage as it's 0-30kcdv, my idea is to use a voltage break down voltage tester but i think it's out put is ac, i need to dig it out to day but what i was thinking is building a rectifier as it has only one output and ground unlike a neon transformer, what bugs me is i have a hipot tester with a load defeat so it wont shut down due to the higher load of recharging the caps, both are 1-2500vdc i am also watching a power supply on flea bay that's in my 10 dolor price range lol,

I am so happy that i can finally used this gear rather then just collecting dust, sure i am vulture of the electronics world but i generally wont throw something away unless it's beyond repair.

I made a divider last night thar does the trick, i dont have the resistors linked but plenty of other banded high voltage resistors, i fine tunes the low voltage side with a pot as my resistors have a larger tolerance, i could not find what i need on flea bay but i am looking, the set up i have a crude but has a accuracy now of +- of about 2 volts

Before they have to hold off 2,500 V and lots of joules, you want to test the divider to make sure the resistors will hold the voltage.

2,500V is not really that high. you might try a voltage multiplier run off 230V from your wall. A Cockcroft-Walton design could be set up for very little:

http://www.allaboutcircuits.com/text...e-multipliers/

A ballasted MOV off a small variac would be inexpensive and more than perfect. Full wave rectify this and you have as much power as you choose to use at voltages in this range.

I have built voltage multipliers in the past, i made a 10 stage one some time back and DLP style projection TV's use a multiplier as well to get around 340 or so volts for the sets ballast to power the UHP lamp, i still have one, when i actively repaired them i made a test rig so i could test customers lamps out side of the TV, I will start getting the parts together to build one as soon as i can I got the breakdown tester our of the shed today and in the process of cleaning it up and testing it, I also found a lamp that i forgot i had, check it out.
Attachment 48596

It came out of an old lighting fixture the military had, it's the only one i have come across that has the trigger inside the lamp as a 3rd terminal, it's a short arc xenon but have no clue to the ratings

I will test the the high voltage resistor, if memory serves i have tested them at a much higher voltage then needed for this project

I made a self contained digital meter with a 1000:1 divider all inside an old plexiglass box that uses an isolated battery for power, i found out the hard way that a second meter i was going to use was not isolated, the main resistor in it is rated to about 10kv so i can leave it sitting on the capacitor bank and act as a way to bleed off the caps.
I used a 10 turn wire pot to compensate for the crappy tolerance of the main resistor, on the low voltage side, it's also in the box for safety
Attachment 48597

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Originally Posted by masterpj

I love this. I have always wanted to learn more about the flashlamp pumping. I know a little bit about it but not enough. Usually had to deal with pictures or text from sams faq or some videos which really do not show the whole construction properly. I also really like that fact that you show an alterntive to xenon. Although on ebay I do see some xenon flash tubes which do look rather affordable to experiment with *if the glass is of the right type*. Thank you so much, maybe I will try to experiment with flash tubes sometime.

Will you ever do a video on ramen shifting? or are the optics/crystals for this too exotic and too expensive to even think about obtaining?
What else would be interesting would be the optical train (hope thats the right word for that) for correction these diode bars. They always look attractive but sourcing their optics is ...uhmmmmm

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Hello,
you can show my ablative air flashlamp from my dye laser Under : http://www.swissrocketman.fr/realisa...e,fr,3,222.cfm

You need a specific energy input between 200 and 1500 J/cm3 to have the ablative regime !
You can use for the external wall plexiglass 10 to 20mm in tickness

Attachment 48608

please correct me is i am wrong but my experience with plexiglass is it will block the short wavelength ultra violet spectrum, I use a sheet of plexiglass as the UV shield with my florescent rock collection that uses a UVC lamp.


Very cool stuff on your web site, thanks for sharing that
Like your dye pump, is that a roller pump? , if i ever get to that level of a laser i have a roller pump that used to be on a bypass machine, i managed to get 3 working pumps during my time at that employer, i used one to pump the fuel out of my water craft,got some strange looks from neighbors but it worked very well