Hah. Exactly! My only concern is that... at a certain point, it's not about collecting the individual wavelengths (I mean, two "445s" are going to be a bit different) but about collecting the diodes/sources/whatevers. That's why, if I ever get a 593.5nm DPSS or HeNe, I wouldn't get the other. The idea, for me, is to build a rainbow, not just have a laser for every 1nm =p That's why I don't think calling a "445nm" diode 450nm (unless it's specced for 450nm) is a fair game.
Well, snagging a cherry picked 460nm diode is better than dropping the $2-3K for a 460nm specced laser.
I also don't know whether to count the Raman HeNe lines, or the 604, since it's part of a ML. Same applies to the tunable AR lines. So that's why I condense it. Could you imagine if I listed each WL individually? My sig would be a mile long...
I consider multiline lasers to count, after all, they are all unique laser emissions. On the other hand, I get where you're coming from, but... I dunno. I suppose that the wavelength changes as the laser heats up, so, to me, it doesn't really count (unless it's not diode). I agree that I would prefer to have all my lines in different lasers so I could view them all at once, side by side, but it's the best I can do at the moment! Maybe one day I will see if I can trade my multiline and a few hundred dollars for a few single lines.
When I get more time, and money, and experience, I'll eventually build a tunable HeNe. Hopefully I can snag some 604, then I will finally see 604 by itself. That's one of my biggest goals with HeNes. As many lines as possible, and seeing 604 by itself.
Just because they only come that way doesn't mean they can't be altered that way! A long term goal is to get some mirrors for the other wavelengths and then make my own external cavity to amplify only those wavelengths.
Honestly, it can get expensive quickly. The fortunate part is that I've gotten over my obsession with just buying cool lasers without thinking. My wallet thanks me.
Plus the 1B laser will provide with days of projects and experimentation, so no need to buy more during that time.
Basic work with HeNes isn't that expensive. Grab a 5mW tube, and a couple HRs, and you can probably get another line or two to lase if you line it up. Won't be permanent without mounts, but still interesting.