Page 1 of 2 12 LastLast
Results 1 to 10 of 12

Thread: Broadband krypton argon mirrors

  1. #1
    Join Date
    Jun 2020
    Location
    massachusetts usa
    Posts
    24

    Default Broadband krypton argon mirrors

    Hey hey,

    I was recently fussing with some random OC's i had in my multiline argon lasers and i found something really amazing. I threw one in my krypton argon laser and I got 13 green and blue lines!!!!! It's super amazing to see in person but that got me thinking. I wanted to get mirrors that did all of those plus 568, 647 and 676. I was asking in Laser Discord and they said some people on here might have some so here I am. I added some pics of the 13 lines (one of the violet/blue lines is really weak and hard to see on camera).
    Click image for larger version. 

Name:	13line.jpg 
Views:	5 
Size:	712.4 KB 
ID:	57512
    If you have any, let me know and we can make a trade or something along those lines.

  2. #2
    mixedgas's Avatar
    mixedgas is offline Creaky Old Award Winning Bastard Technologist
    Infinitus Excellentia Ion Laser Dominatus
    Join Date
    May 2007
    Location
    A lab with some dripping water on the floor.
    Posts
    9,433

    Default

    I've had 18 lines out of a customized Air-cooled. We adjusted the Ar/KR ratio and pressure for maximum color. Not maximum power, or best color balance, that is a different thing.

    I'm assuming from your other posts, you have a 643 or similar Air Cooled.

    Different gas mixture ratios support different lines. Just because you have a mix, does not mean you'll get everything that can theoretically lase. This is tuned at the factory.

    If you have an Omnichrome 643, generally if it has mixed gas or krypton in it, it usually ships with an "All Lines" rear mirror that covers violet through deep red. Argon only models get a Argon Lines Only HR.

    Now for the bad news, the "All Lines/Whitelight " OC is exceptionally rare. Here is why. The 568 Yellow and 647 Red compete with each other for power. The Red/Yellow ratio is dependent on tube pressure, cataphoresis, operational current, gas ratio and magnetic field. Especially magnetic field. While the 643 does not have a field electromagnet, it very much has cataphoresis. So the arc causes the krypton and argon to want to separate from each other, and this does weird things when the heavier atom is slower to pass down the internal gas returns. Cataphoresis driven gas pumping happens in all gas lasers to some extent. It is not unusual for a mixed gas laser to be very sensitive and shift the yellow/red ratio back and forth. Which is why early laser show ion lasers had variable magnet current to tune the field. A second very weak yellow is often available at 575 nm that does not compete like 568 nm does with 647.

    Short story, very few Biological customers want green, as it causes cross talk in DNA scanners, Confocal Microscopes, and Cell Sorters. So most optics out there are "kill green" by having extra transmission in the coating at 515-532 nm. That dispatches the unwanted lasing. A secondary reason is the 530 nm KR line steals energy from two other lines, one of which, if I remember right, is the yellow.

    I have a chart of the optics groupings some place. If you can find a dead prism tunable RYGB 643 head, guess what the OC is! There are a few all lines systems out there, but the main customer for mixed lasers, Biological Imaging, did NOT want either the power ratio issue or green light to mask their desired signals. if its stained or dyed biological tissue, odds are the primary fluorescence is blue for nuclei (DAPI dye) or green or yellow (TRITC dye ) for everything else like cell walls. We use DAPI and TRITC at work, and any stray green light kills the experiment in our case.

    I'll find the model chart.

    I do have about 70 pieces of used, old 15 mm small, medium , and large frame Whitelight Optics, but you use a 0.25" / 7 mm optic if I'm correct. My bet is I may have a older large frame all lines HR that leaks enough for you to have some fun. Small and mediumframe HRs don't leak much , but the tailored coatings on large frame HR optics often leak @ say 0.25%. I don't know why, but they do.

    Yes, the super magnet trick has been done, but its easy on ALC as they have a steel cooling box. On Omni products with the aluminum fins, it is not so easy to get a magnet close enough. The magent(s) tends to want to fling itself towards the magnetic Nickle/iron alloy end bells, either shorting something or breaking the Brewster Stems, even if you use epoxy or 3D printing to make a magnet holder.


    My immediate thought when I considered selling you my sole remaining all lines miniature OC, was "over my dead body". At 0.5% average transmission, that is one rare optic when a larger tube starts at 1.5 and up. More common is a RRYB or RYYB OC.
    A trick you could try is to align an external , long radius, red hene OC with your current all lines configuration, using a mirror mount like a MM1 or MM2 with 80 pitch screws. You may see a weak set of All Lines. Watch your eyes when aligning a back reflector aka "three mirror" cavity. Not to mention it was a 250$ piece of glass, in 1990s Dollars.


    These optics are all tuned to a purpose when coating. Lines with more gain get less reflectivity in the coating, as to let out more power from the cavity.

    I have some strange broadband and narrowband mirrors in my rather large collection, drop me a PM and I might have some things you can play with cheap. Some are even 7 mm.

    I own two ILT krypton only heads, so I have already done this experiment long ago.

    Steve
    Last edited by mixedgas; 01-07-2021 at 10:55.
    Qui habet Christos, habet Vitam!
    I should have rented the space under my name for advertising.
    When I still could have...

  3. #3
    Join Date
    May 2009
    Location
    UCSB
    Posts
    708

    Default

    Like Steve said, its tricky business to make it happen. Your best bet would be one of the green kill OC's plus a 3rd OC for the green. Aligning the 3rd OC is trivial, since you just aim the retro reflection back into the laser -- I have done it by just holding the mirror in my hand before

    Another fun trick is to just aim the back reflection from the grating you are using to monitor the beams with back into the OC. Depending on the grating and operating conditions you might get an extra line or two (especially if it is a green kill OC).

  4. #4
    Join Date
    Jun 2020
    Location
    massachusetts usa
    Posts
    24

    Default

    I actually have a green kill one. I was fussing with multiple OC's and I got a weak 568 out which would make sense since the greens are stealing all the power. if I adjust the OC so the greens die down a bit, the 568 line gets stronger as predicted. I appreciate the help. I think i'll probably toy with this a bunch until I get enough lines for my taste, haha. still have a bucket of other random OC's to try so maybe I'll find a nice combo.
    Click image for larger version. 

Name:	image0 (7).jpg 
Views:	2 
Size:	239.7 KB 
ID:	57513Click image for larger version. 

Name:	image1 (2).jpg 
Views:	2 
Size:	1.37 MB 
ID:	57514Click image for larger version. 

Name:	image0 (8).jpg 
Views:	2 
Size:	724.8 KB 
ID:	57515

  5. #5
    mixedgas's Avatar
    mixedgas is offline Creaky Old Award Winning Bastard Technologist
    Infinitus Excellentia Ion Laser Dominatus
    Join Date
    May 2007
    Location
    A lab with some dripping water on the floor.
    Posts
    9,433

    Default

    Call me if and when you hit KR 687.096 I'm one of only three people I know who have seen it in the last two decades...
    Showed up when a large frame whitelight OC was stuck on a Lexel 95 Krypton. Yep, Three REDS.... I think you have to pretty much kill 647 to get it.
    657 only shows up in very low pressure pulsed tubes so far. I do have the 752, and 799s because of work. Not quite everything , but most, are in the list below.

    If you find a spare all lines OC in good shape, let me know, I'm always interested. I have a few weird HRs, like yellow-green only in 7 mm. Probably have a dozen Blue-Yellow only, which results in a white (yes, the eye sees it as white) beam,

    I'm still looking for the CW 550 nm Argon line, I've seen brief flashes, but nothing stable. Think low gain and large frame laser for that one. I know one fellow who saw it with two Lexel tubes in series.

    From Bridges et Al Visible and uv Laser Oscillation at 118 Wavelengths in Ionized Neon, Argon, Krypton, Xenon, Oxygen, and Other Gases:

    II means doubly ionized, III means triply ionized. In your case to get a III you'd have to nearly destroy if not melt the tube.

    Krypton

    3239.2 0.5 3239.51 III 5p"' D2 - 5s P
    3375.0 4 0.5 3374.96 III 5p"' D3 -5s" 'P0 2
    3507.42 0.06 *3507.42 III 5p 'P2 - 5s IS',
    4067.36 t 0.06 *4067.37 III 5p' F-3 - 5s' 'D',
    4131.38 0.06 *4131.33 III 5p 5P2 5s S1
    4154.45 0.04 4154.44 III 5p' 3F3 - 5s' 'D',
    4171.81 0.1 4171.79 III 5p 'Pi- 5s 3S30
    4226.51 t 0.06 4226.58 III 5p' 3F2 - 4d' D,
    4443.28 0.04 4443.29 III 5p' D2 - 4d' D 1
    4577.20 0.1 4577.20 II 5p' 'F'7/2 - 5s' 'D5/2
    4619.17 0. 1 *4619.15 II 5p 2D0 5/2 - 5s 2P3/2
    4633.92 t 0.06 4633.86 II 5p' 2F0
    5/2 - 5s' 2D3 ,2
    4650.16 4 0.1 4650.16 IIa 5p 2P12 - 5s 4P,,2
    4680.45 0.06 *4680.41 II 5p 2SO 2 - 5s 2Pp/2
    4762.44 : 0.06 *4762.43 II 5p 2D%,2 - 5s 2P, 2
    4765.71 0.1 4765.73 II 5p 4
    D0
    5/2 _ 5s 4P3/2
    4825.18 0.06 *4825.17 II 5p 4S-3/2 - 5s 2P,,2
    4846.66 4 0.06 4846.59 II 5p 2P' 1/-2 -5s 2P3,2
    5208.324t 0.04 5208.31 II 5p 4
    P-l2 -Ss 4P3/2
    5308.684- 0.04 5308.65 II 5p 4P0
    5
    /2 - 5s 4P3/2
    5681.92 t 0.04 *5681.88 II 5p 4D0
    3/2 - 5s 2P3,2
    6471.0 0. 5 *6470.88 II 5p 4
    P0
    5/2 - 5s 2P3,2
    6570.0 0.5 6570.12 II 5p' 2D5/2 - 4d 2F5/2
    6764.57 0. 06 6764.42 II 5p 4
    P0
    1 -2 - 5s 2P,2
    6870.96 0.06 6870.84 II 5p' 2'5/2 - 4d 2P3,2
    7993.0 t 0.5 7993.22 II 5p 4
    P3/2 - 4d 4D,/2
    Last edited by mixedgas; 01-07-2021 at 13:49.
    Qui habet Christos, habet Vitam!
    I should have rented the space under my name for advertising.
    When I still could have...

  6. #6
    Join Date
    Jun 2020
    Location
    massachusetts usa
    Posts
    24

    Default

    Wow i never knew there were three reds! i hope someday I get to see it but for now, heres what I got. I think 15 lines. The deeper violets are so dim and almost impossible to pick up on camera. I can barely see them in person so i might've miscounted them.
    Click image for larger version. 

Name:	image0 (14).jpg 
Views:	3 
Size:	682.8 KB 
ID:	57516Click image for larger version. 

Name:	image0 (9).jpg 
Views:	3 
Size:	1.17 MB 
ID:	57517

  7. #7
    mixedgas's Avatar
    mixedgas is offline Creaky Old Award Winning Bastard Technologist
    Infinitus Excellentia Ion Laser Dominatus
    Join Date
    May 2007
    Location
    A lab with some dripping water on the floor.
    Posts
    9,433

    Default

    Fun, is it not?

    Steve
    Qui habet Christos, habet Vitam!
    I should have rented the space under my name for advertising.
    When I still could have...

  8. #8
    Join Date
    Jun 2020
    Location
    massachusetts usa
    Posts
    24

    Default

    Quote Originally Posted by mixedgas View Post
    Fun, is it not?

    Steve
    extremely fun! just experimenting with the different combos is so super interesting! I found one OC that gives me this lovely pink beam. If I throw an HR in the mix, I get a rich yellow from the 568 and 647. Im having a blast, haha.

  9. #9
    mixedgas's Avatar
    mixedgas is offline Creaky Old Award Winning Bastard Technologist
    Infinitus Excellentia Ion Laser Dominatus
    Join Date
    May 2007
    Location
    A lab with some dripping water on the floor.
    Posts
    9,433

    Default

    How may optics do you have?
    Steve
    Qui habet Christos, habet Vitam!
    I should have rented the space under my name for advertising.
    When I still could have...

  10. #10
    Join Date
    Jun 2020
    Location
    massachusetts usa
    Posts
    24

    Default

    i have 4 sets of argon mirrors. 2 from dead argons and 2 from ones currently working that I often swap around.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •