LARGE HeNe/gas collection and reference thread.

[Sigurthr]

Oooooo nitrogen lasers are so freaking sexy. I have everything needed to make a TEA laser except the damn electrodes. I can't get Al angle or sheets anywhere. That and no space for such a project, haha.

Brewster tubes are awesome even iv you just use a standard 633 OC because the intercavity power can be TENS of watts!

 

[bloompyle]

An N2/TEA is not going to be easy in a dorm scenario, but there are a few wavelengths that I really want to recreate and witness, and this seems to be the only way. So I'm willing to try.

Plus it gives plenty of options when using different windows and mirrors. It's a playground full of photon sand.

 

[scumbagatheist]

Good Gawd, gentlemen! Ok, so where does a gas noob start when it comes to gas lasers? That learning curve seems extremely steep, even for someone already familiar with lasers!

 

[IsaacT]

You should probably start with a simple HeNe. Go too far, and I doubt you will be as impressed by the regular ol' 633 HeNe's. Then I would say go for a Green HeNe, or a GreeNe. Then talk ta Dr. Sam from Sam's LASER FAQ and save your pennies.

For Argon Lasers i believe Dave still has a powerful Multiline but it will cost you ~500 dollars shipped.

 

[Sigurthr]

It only seems steep until you're in up to your ankles feeling the photon stream between your toes.

A standard 633nm HeNe is the standard entrance fee. Uncased/bare tubes tend to speed up things. Additional wavelengths or gasses are the next step. HeCd is a RARE gem to find working. HeHg is another fine jewel with no commercial manufacturing, so DIY is the common source. N2 lasers are very DIY friendly if you don't mind lethal HV present. CO2 lasers are a lot of fun and relatively safe for their output power - HV aside. Copper vapor lasers are more exotic and hard to produce given the high temp needed by the lasing medium. Sodium vapor lasers are yet unrealized by hobbyists, but oh, we can dram can't we?!

A world of fantastic opportunities await you once you've opened the floodgates.

 

[scumbagatheist]

You mean to tell me that folks are doing DIY tubes? I have a laser customer and old time friend who is a professional glass blower!

Oh...too much excitement for one night. Off to read the stickies and faq's and such. I have been setting myself up for my entree fee into the gas world @ $500. I've been saving pennies and getting more contracted builds. I know I just have to have a pretty great multi-line Argon Ion for all those beautiful wavelengths.

Once I have a toy to satisfy my impulses, then I can relax and spend the time getting into the various gas types. I know I like bare tubes as compared to enclosed...let me see plasma!

All that being said, my SO has me on a strict "no gas lasers" contract until we move in the fall. It's not a matter of power; It's a matter of space...we simply don't have space for a tube...unless it's a lamp! :crackup:

 

[IsaacT]

Get a small HeNe Tube, and stick it on top of an enclosure like I did with mine(check my sig if you haven't seen it). It takes up like no space and costs very little. Mine cost me 30 bucks total, but the tube was a gift. You could probably get a decent setup for 50 dollars! And literally the size of a normal sized book.

 

[scumbagatheist]

Get a small HeNe Tube, and stick it on top of an enclosure like I did with mine(check my sig if you haven't seen it). It takes up like no space and costs very little. Mine cost me 30 bucks total, but the tube was a gift. You could probably get a decent setup for 50 dollars! And literally the size of a normal sized book.

Always with the good ideas...It looks like I'm busy with other projects for the next couple of months anyway...best I spend that time boning up on my homework!

 

[Sigurthr]

Yup there are DIY tube lasers! Quite good ones too. The best thing about nitrogen, copper, and lead lasers is that they are superluminous; no mirrors needed!

 

[scumbagatheist]

So, how does one go about creating a vacuum in one's already custom tube, and then allow in the precise amounts of combined gases, and then seal the tubes, all in the matter of a hobby?

It seems like this is on the severely serious side of the hobby, and limited to those with vast experience and expendable cash.

 

[IsaacT]

Read up HERE. Also, I know there was an article telling how to build one a long time ago in a science magazine, but I forget the name.

It is very difficult but if you can find that instruction bit in that magazine, then you might could well manage it.

 

[Sigurthr]

I know of several hobbyists who have done such in the Tesla Coiling hobby for custom discharge tubes. I have five of these tubes myself. The hard part is electrodes and Brewster windows. The vacuum and gas mix is the easy part.

Due to the differences in thermal expansion coefficients it is very hard to create a deal between glass and metal. Typically nickel wire and uranium doped glass were used as electrodes a d intermediary boundary layers to allow for compensation of this. U glass is hard to find these days and knowing the inhalation risk most glass workers are hesitant to work with it. I only know of one hobbyist who will do tubes with electrodes and I don't think he has the skills or tools to do a Brewster window.

It would probably be better to find an outgassed HeNe Brewster tube and regas it with your mix.

Btw, here is a taste of the spoils; an Eight Line HeSe laser using ML Argon mirrors that is in the multi-watt output power range. More than 16 more lines are possible if you had a wideband HR and OC pair.

 

[scumbagatheist]

See, this is what I'm talking about!

 

[bloompyle]

Yeah, what they said.

Good information Sig!

Some of the hardest things with DIY gas tubes, is heat. With copper, one has to ionize the copper to the point where it can be lased. There are 2 methods.

2 PSUs pulsed between each other, like:
10101010
01010101
One psu makes it a gas capable to lase, another, slightly higher output psu then pulses to lase the gas. This repeats.
Or the harder method, getting a psu outputting enough, making it hot enough, to be constantly ionized and always able to lase. However, BOTH are still pulsed though in this case, it just doesn't allow the copper to cool between pulses, allowing the use of a single PSU. Though the gains are magnificent. 510.6nm and 578.2nm, in the WATTS range. It's a good dream...

 

[IsaacT]

Time to look for a copper laser....would be so much money though lol!

 

[bloompyle]

Get a grant...