Post your interesting eBay finds...

[SoulFeast]

I get 612, ~630 clump, 640, and 650. That picture where you can see the 3 separate lines in the middle was done after sending it through a grating, prism, and another prism

[lasersam]

This shows 7 lines *yes 7* from SoulFeast's laser. It was made with a lens and single diffraction grating. Playing with the lens focal length would get the spots to be smaller. The 7th line is a weak one above 650 nm (perhaps 652 or 653 nm) that is not always there.

--- sam

[SoulFeast]

When you sent me that picture, I just thought that extra "line" was an artifact since it was never mentioned. Once I get a set of helping hands, I will be glad to play with lenses. Unfortunately I have no way to stabilize lenses at the moment..

Not willing to edit every post to say 7 line back on LPF...

Scouring my literature for other lines above 650, judging by the proximity of the 2 lines, in comparison to 633 vs 629/635 it does look like 652 is a decent candidate. Though I have yet to see this on my own. Will have to look out for it!

[lasersam]

There is possibly a "4 wave mixing line" at 652.5 nm. This may not even be discussed in the literature other than the Laser FAQ.

--- sam

[SoulFeast]

I'll research it. So far I've seen 543, 594, 604, 612, 629, 633, 635, 640, 730, 1152, 2395, and 3391. No mentioning of 650 or 652.5. Although the 2395nm line is news to me, and I've only briefly seen 730nm mentioned.

I'll keep an eye out for the two lines in question, might find something on why they are so elusive, or better, ignored.

[laserist]

I don't have a link to the listening, but a couple months ago I was able to snag a working Ohmeda Raman particle counter off of ebay for $125. Still operates in 6 lines, just took some severe gas doctoring to revive a presumably dead soft seal.

Is this case of thread hijacking because you intend to put one of these on ebay in the future?

[SoulFeast]

The title of the thread is "Post your interesting ebay finds". I think a 7 line, working Ohmeda HeNe, that was found on ebay, qualifies. Nowhere did it say that it has to be something currently for sale.

[lasersam]

I'll research it. So far I've seen 543, 594, 604, 612, 629, 633, 635, 640, 730, 1152, 2395, and 3391. No mentioning of 650 or 652.5. Although the 2395nm line is news to me, and I've only briefly seen 730nm mentioned.

I'll keep an eye out for the two lines in question, might find something on why they are so elusive, or better, ignored.

All of those are normal HeNe transitions. There are actually many more than found in common texts.

The 650 nm and suspect 652.5 nm lines are not normal HeNe transitions, and may only be found in a handful of research papers and the Laser FAQ. I doubt they will appear in any texts.

--- sam

[SoulFeast]

What gets me is that most of these transmissions (excluding 543, 594, 612, and 633) are only found in unique applications. I've only seen 604 in my MLs and in the REO LST tunable. As far as the others, the Raman lines, I have only read of them in the Ohemdas (Ohmedi?)

What intrigues me currently are the ring lasers.

I also plan to try building a copper/gold vapor eventually. However, in my current quarters, a project isn't totally feasible.

This threadjacking is undesired, so I am going to stick to our emails now

[The_Doctor]

This threadjacking is undesired, so I am going to stick to our emails now

No, no... 'Illegitimus non carborundum', says I. Don't let carping from the sidelines stop you. Besides, you appear to have got Sam posting here, causing a moment of quiet wonder in me that has persisted for 24 hours now, seeing that. Hello Sam.