Why Gas?

[lasergal]

I like the Steampunk look of it.

Diodes are boring. But you get that plasma glow in the tube, running on high voltage, outputting a tight beam of light, and its like magic.

This. Totally!

 

[icecruncher]

The more I look and research, the more I realize I dont know anything about anything about gas lasers. Id probably buy some part of a bomb for all I know. I have no idea what to purchase.

Learn learn time :thinking:

Learning Gas Lasers, IMHO best place to start (and most would agree):

Sam's Laser FAQs

Sam (Sam Goldwasser) is also a good place to check if you want to purchase and know what you are getting. There is a Sam's Laser FAQs classifieds.

Although you can often get items cheaper than on his classifieds, I doubt you will EVER meet anyone who know more about them than he does.

Sam's Laser FAQ: Welcome Page
Sam's Laser FAQ - Preface, Introduction, What is a Laser?, Safety
Sam's Classified Page

 

[Berc12321]

Learning Gas Lasers, IMHO best place to start (and most would agree):

Sam's Laser FAQs

Sam (Sam Goldwasser) is also a good place to check if you want to purchase and know what you are getting. There is a Sam's Laser FAQs classifieds.

Although you can often get items cheaper than on his classifieds, I doubt you will EVER meet anyone who know more about them than he does.

Sam's Laser FAQ: Welcome Page
Sam's Laser FAQ - Preface, Introduction, What is a Laser?, Safety
Sam's Classified Page

Just found my next novel.... Thanks!

 

[weeba2kv]

i love gas lasers because they have sugh a nice tight beam , low div.

 

[Roam]

it makes it a lot more exciting when you look at the tube and realize that the orange-red color of the plasma has its origin in the spontaneous emission that depopulates 2p levels back to the first excited state in order to sustain the inversion in Neon. This will never happen in a diode.

Edit: The only reason those HeNe's are expensive now is because they are no longer in mass production. The CO2 laser is still quite efficient, you can get a ~40 W tube for just <$200. The copper laser is also efficient (being the most powerful laser in the visible spectrum), but hard to manufacture.

 

[hakzaw1]

The more I look and research, the more I realize I dont know anything about anything about gas lasers. Id probably buy some part of a bomb for all I know. I have no idea what to purchase.

Learn learn time :thinking:

^^^ maybe you should place a WTB here at LPF (BS&T) and get one from a trusted vet.

@roam +2 for the good post
@icecruncher ditto-- Sam is the MAN- & wasnt he a joy to meet at SELEM?? Very kind and humble gent.


hak

 

[vk2fro]

I grew up with gas lasers. Oatley electronics used to sell them, all sorts of HeNe's and at one point an NEC Argon. I still have an NEC Argon tube (in defunct state) as it brought back fond memories of my early teens playing with amps of current at suitably stupid voltage levels to get the silly thing to run.

You can't put the house into darkness tripping the breakers with a diode. Hell you cant even do it with a HeNe unless you try really hard, but the inrush current on even a small Argon with a homegrown supply without making an inrush limiter is tremendous. I tripped the breaker several times and pissed off the family each time I tried to fire that puppy up. I eventually wised up and put in an inrush limiter (to slow down the cap charging), and hung it off the preheat timer. Now my laser didn't trip fuses.

Beams from gas discharge lasers are a world apart from the terrible specs you get from diodes. Ions do require monthly maintenance (in the form of a run for a hour or so) to keep them healthy, but HeNe's are as reliable as a fluoro tube - they'll wink on on command and very rarely fail.

They all have one common danger. Gas tubes require high voltage. The HeNe supplies will give you a nasty kick if you come into contact with the output. An Ion supply will kill you if your not careful. Depending on the design, an Ion will run anywhere from 90V to 400v DC, at anywhere from 5 to 40 amps. This in itself is lethal, and then on top of that; the 2kv trigger voltage is also there during starting (and its a fairly hefty current as well). Many contain capacitors that will retain a lethal charge for hours after switch off, if bleed resistors are not fitted or have failed. So one must be very careful with Ion laser supplies. Also some Ion tubes are made of carcinogenic material so dont break them

 

[argon]

With gas lasers, you can perform experiments, which are not possible with diode lasers. For example you can build an external cavity to activate other wavelengths. With a special prism, you can choose between the different wavelength... these types of experiments can't be done with diode lasers.

The cavity of ion lasers often can be adjusted, other mirrors can be mounted, the whole laser can be maintained. Gas lasers are hobby of its own.

Best regards
argon

 

[mojo_1234]

gas? DPSS? diodes?

I do agree with most of the gas owners in this forum - if you would like to see a laser working a HeNe laser is the one to choose... it's a piece of art. Especially a green HeNe is amazing: red glowing tube and a "pencil" thin green beam

And for argon lasers - I do have a nice ALC 60 head doing around 9!!! different laser lines - all kind of colours between dark blue and green... and my local supplier of electric energy has become one of my best friends...

With a simple diode laser - sure - you've plenty of power and what ever - but it's just an amazing light source... and with these strong 445nm LDs one mistake and you're blind (ok, a gas laser may zap you to sudden death - but with isolation this should not be the problemo).

Recommendation: Just try to get a cheap HeNe... you'll see

 

[vk2fro]

hehe yep and a hene inverter will give you a good wallop too - it wont kill you, but it packs a good kick

Like I mentioned before, an argon psu (especially a big one) will kill you, no second chances. And it can do this even after its been switched off if capacitor bleed resistors have gone open.

Argons are high maintenance, but worth it. Get a good multiline one and it will output 150mw+ of at least 6 different wavelengths, from a shoebox sized laser. Of course this is total power - the green and blue lines are the most powerful

 

[DJZ]

Whats the advantage over diode lasers?

Well, when it comes to laser show projectors, I need no stinking dichros! Dichros are used to combine the different wavelengths together inside a projector just before the beams are scanned.

I saw a couple folks mention argon lasers and the various blue and green lines they emit. If you add krypton gas to the argon with a special set of optics you end up with a white beam. I was amazed last year to see a Laser Physics Reliant sell on ebay for $200. This was an Argon/Krypton laser, if it worked, they output around 300mW and around 12 lines of color. Tube voltage is around 180VDC and tube current is up to 12Amps. So for over 2KW of power you end up with .0003KW of light. But it's worth it!

 

[Things]

Well, when it comes to laser show projectors, I need no stinking dichros!

What's the price difference between a PCAOM and a dichro these days??

 

[DJZ]

What's the price difference between a PCAOM and a dichro these days??

Touche!

Although, the last one I bought I only paid $250, 8 channel with a 10W crystal. And I don't have to worry about near field and far field divergence. There are many major benefits to running projectors with solid state now. If I wanted real power out of my projector I need 3 phase and water cooling for a much bigger ION. A buddy of mine runs a guitar shop and swears by the old tube amps and how much better they sound. In a loosely connected way I agree when it comes to lasers.

 

[Things]

Yeah, any gas is going to far exceed the beam specs you could get out of any diode setup. Those high power whitelights floating around look awesome, but I can see why they'd be a pain in the @ss to use for some setups.

 

[vk2fro]

Gas is nice, but nothing beats plugging a 5 watt solid state projector into a common household power point, and a laptop and pressing the go button. No 3 phase, no water loops, just plug it in and your ready to go.