Laserscope 800 / ALE YD4 Arc Lamp Power Supply

[turbohead]

Would you be willing to share your documentation, perhaps via PM? Would it apply to the YD-LS model?

[dsli_jon]

...I made a "controller" based on the one posted on the web by Mr. DJ ...I checked the wiring diagram posted on the web with the interlock diagram in the manual available from TDK-Lambda, and they agree:

..Which-manual isn't for the -LS..

The controller works on my other ALE without any issues.

..which - also - isn't a -LS, amirite? You see the 'common-denominator' here, yes? :P

We can discuss this offline...
L8r
j

[planters]

Jon,
Your conversion of the LS that I use is humming away without a hitch. Thanks.

The basic concept of a high voltage triggered, low voltage/high current maintained arc lamp power supply is simple. They operate in millions of HID light sources (those that haven't converted to florescent or LED, but that's a different topic). The rub is the SPECIFIC operation of the arc lamps that power the LS and the even more idiosyncratic P. supplies the drive the Greenlight lamps.

This may be more a question for Steve. Can't a generic arc lamp power supply (the LS would just be one of a number of possible sources) that works and whose use is less controversial, drive the lamps in turbohead's DIY YAG?

[pompanopatjr]

Anyone interested in a Paragon 100 CO2 Laser ...

[mixedgas]

Planters,

Yes, a Generic Industrial or Scientific lamp supply capable of 40-50 amps current limited and 250V DC will drive the regular Laserscope 700s or 800s.

As the damn things are generally huge, there are very few commercial lamp supplies that would fit in the Laserscope Frame. If you don't mind a external rack supply, well used ones go for 300$ or so, but have even worse or non-existent documentation then the ALE. Many of the cheap ones come with the required 100 pound isolation transformers needed by older designs. :-)


A transformerless OEM DRIVE set (trigger board, lamp power supply, no case or enclosure ) from Analog Modules is ~1600$ and shipping.
A OEM 19" rack lamp supply new is ~3000$ from the two remaining vendors, one in China, One is USA.

The Greenlight series will NOT interface well to a standard lamp PSU due to specialized current pulse requirements for Arc Pumped Greenlight.
Newer Laserscopes use a simmering lamp with a pulsed current profile synced to the Q-Switch I'm not privy to the details. If asked, I'll deny who told me they can do it (two of them requested I never reveal their identity)

Even the classic YLS is capable of some fast current profile shifts. Laserscope has a patent on the enhanced power pulse technique and they actively enforce it. No I do NOT know the details.

Steve

[mixedgas]

Anyone interested in a Paragon 100 CO2 Laser ...

Look, I'm the one guy who can help you by sending you to Mark in Florida who has some large CO2 PSUs. But your annoying me by jumping into other threads.
I hate to play MOD but this is getting excessive.

Steve

[pompanopatjr]

I read you loud and clear, its not easy posting with this Smart Phone. .. you will not have a problem again. .. thanks for the Help. ... ☆★☆★

[Draco]

just wondering but what is the general fail modes for these types of lamps? to the just fail to start, explode like some metal halide HID or just darken because of electrode sputtering?
My living room is illuminated by "power-ball" metal halide in a protected fixture but for laser arc lamps I had thought they just had krypton or xenon so no halides to eat the tube, the only time i had a xenon fail was when i pumped a camera tube with enough power to cause it to explode

[mixedgas]

These fail by 1. Exploding 2. Getting Hard Starting 3. Reduced Light output over time from solarization and the quartz turning white. 4. If you season the electrodes to a high current, over time they get conditioned to only running well at high currents, commercial users otther then laserscope keep the lamp current very much constant if they can.
5. If the DI water surrounding the lamp is not DI enough, the PSU arcs to the reflector instead of lighting the lamp.

State 1 in a LS often takes the YAG rod with it. State 5 pretty much ruins the overall efficiency and you need a very expensive reflector..

Steve

[planters]

I have some ideas about where I would to go with these lasers. These are just thought experiments, but I believe they are interesting. Molded, pressed PTFE reflectance material for these housings seems like it would be an improvement over the gold and ceramic reflectors that are currently used. Multiple companies market it and it has >99% reflectance in the 800nm to 900nm pump bands. Able to work wet, these are substantially better than the glazed ceramic reflectors which operate around 97%. This is significant because the light bounces multiple times from these cavity walls. The decay of the pump light as it is lost to the rod or from the chamber is proportional to the ratio of rod diameter to chamber diameter and if you look at this ratio, a substantial amount of light bounces more than a dozen times. Also, the glazing, which prevents the ceramic from absorbing water, causes some specular component to the reflection which can cause hot spots. The PTFE material is almost perfectly lambertian.

I am not knowledgeable enough to build an arc lamp driver myself, but I do know that there are a lot of similarities between a modulated arc lamp and a broad pulsed flash lamp, from the lamp's point of view. With the Q switch driver's controller it would seem that a signal could be sent to the current control on the lamps to allow the current to be modulated. The depth of the modulation could be limited to not dip below the current needed to sustain the arc, but because of the duty cycle, the peak could be substantially greater than the 40 A typically used in a LS. Even if coordination with the Q switch was completely ignored the greater than linear output of the laser with current should increase efficiency. However, if some arbitrary frequency is selected (you have to choose something), it seems obvious that peaking the lamp while the switch is allowing the crystal to dump is attractive.

I'm not going commercial. I'm not going to sell anything nor do I suggest anyone should or will...just thinking.