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Thread: Nitrogen Laser teardown, and dye laser demo!

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    Default Nitrogen Laser teardown, and dye laser demo!

    I though you guys might appreciate this video.

    An LSI Nitrogen Laser teardown, and a Dye Laser Demo!

    https://m.youtube.com/watch?v=US3vLJIUGoU

    Cheers!

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    Quote Originally Posted by plazmatron View Post
    I though you guys might appreciate this video.

    An LSI Nitrogen Laser teardown, and a Dye Laser Demo!

    https://m.youtube.com/watch?v=US3vLJIUGoU

    Cheers!

    Really awesome video! Thank you for sharing!

    What kind of peak powers are needed for the dye to achieve a lasing state? I would imagine pretty high considering there are no CW diode pumped dye lasers.
    Last edited by absolom7691; 07-04-2020 at 15:56.
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    There are now CW diode pumped dye lasers, but required active cavity length matching, locking, diode wavelength and linewidth narrowing, a custom 4 mirror ring cavity, and custom chemically modified dyes are required to work with a 445 pump. Two dyes are used as a donor-receptor pair. For a few microwatts...

    Not easy enough yet... Done by an skilled organic chemist who could "grow" her own dyes and had a hardware capable team to do the rest.

    Really Nice construction on the dye laser, but you might want to switch the rear mirror to a 1200 LPI grating. Usually an intracity telescope helps use the grating more effectively, but you can get away without it. I'm sure you found a flat-flat cavity to be a bit challenging to align.

    Steve
    Last edited by mixedgas; 07-04-2020 at 17:54.
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    ... the needed peak powers are pretty high! - my Nitromite emits 200ps long pulses at roughly 400 Kilowatts(!!) peak power with a repetition rate of 30 Hz (averaged in the Milliwatts).

    Viktor
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    Quote Originally Posted by mixedgas View Post
    There are now CW diode pumped dye lasers, but required active cavity length matching, locking, diode wavelength and linewidth narrowing, a custom 4 mirror ring cavity, and custom chemically modified dyes are required to work with a 445 pump. Two dyes are used as a donor-receptor pair. For a few microwatts...

    Not easy enough yet... Done by an skilled organic chemist who could "grow" her own dyes and had a hardware capable team to do the rest.

    Really Nice construction on the dye laser, but you might want to switch the rear mirror to a 1200 LPI grating. Usually an intracity telescope helps use the grating more effectively, but you can get away without it. I'm sure you found a flat-flat cavity to be a bit challenging to align.

    Steve

    Thanks for all the comments guys.

    Sure, yes, you can drive them with Diode Lasers, but only under specific circumstances with a very well designed cavity. I have seen a couple of academic papers on this. It certainly looks possible, but output powers seem so low, I might as well invest my time in making a mini Nitrogen Laser.

    On power required to pump a dye like this, both the dyes in the video are high gain. I have not managed to pump lower gain dyes like Fluorescein in this setup (~36kW), however they run just fine with my home made Nitrogen Lasers (guessed power of ~300kW!) Those things will lase just about any fluorescent dye, and with no cavity either!

    I am waiting on a suitable grating showing up at a reasonable price, then I can tune the thing.

    Flat-flat cavity Alignment is not too terrible for these. There are a couple of options:
    Drive it at high repetition rate in a darkened room and observe the uncollimated output. If you are close, there is normally 'something' in there.

    Or my favourite method, put it in front of a more powerful Nitrogen laser that can drive it to super-radiance. Even if the mirrors are way out, it will lase anyway, so alignment becomes trivial

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    ... yes, exactly my point -- power rulez!!

    Viktor
    Aufruf zum Projekt "Müll-freie Meere" - https://reprap.org/forum/list.php?426
    Call for the project "garbage-free seas" - https://reprap.org/forum/list.php?425

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    Default New Video up of High Power Home made Nitrogen Lasers!

    In this video, I show three of my high performance designs for Home made TEA nitrogen Lasers.Although these are quite simple to build, these are difficult to build well. My fist ever TEA Laser was held together with gravity and glue. The ones demonstrated here are worlds away from those first attempts!The two Charge Transfer Laser demonstrated, have high repetition rates, high output powers (peak and average) and are robust, with many thousands of shots possible before the dielectric has to be replaced.These can easily drive a Dye Laser to threshold, in fact the peak power is Dyes can be Lased Superradiantly (Feedback is so high, no mirrors are needed!)

    https://www.youtube.com/watch?v=pCnXftuJ9Zo

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    Wow...
    Hexagonal rods ordered yesterday after viewing video. Arrived today.
    Already had the caps. Your work is to be commended.

    Any idea if adding a little silicon carbide or hacksaw blade pre-ionizer will boost the output?

    Steve
    Last edited by mixedgas; 08-07-2020 at 18:20.
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    Quote Originally Posted by mixedgas View Post
    Wow...
    Hexagonal rods ordered yesterday after viewing video. Arrived today.
    Already had the caps. Your work is to be commended.

    Any idea if adding a little silicon carbide or hacksaw blade pre-ionizer will boost the output?

    Steve
    Awesome,thanks! Let me know how you get on.

    I tried carbide paper strips (various grades) but honestly, I did not observe much difference.
    I suppose if you scaled it up, then you would probably need something like that.

  10. #10
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    Default New N2/Dye laser video

    Hi all,

    I added a diffraction grating to the Dye Laser, it is now tunable!

    https://www.youtube.com/watch?v=q9zQ3_Kjxd8


    Enjoy,

    Les

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