Page 1 of 38 1234511 ... LastLast
Results 1 to 10 of 372

Thread: The Big Green Thread (I'm gonna regret posting this in the morning)

  1. #1
    Join Date
    Jan 2007
    Location
    Florida
    Posts
    4,382

    Default The Big Green Thread (I'm gonna regret posting this in the morning)

    -post deleted- _____ xx
    Last edited by steve-o; 11-01-2012 at 04:22.

  2. #2
    Join Date
    Jan 2007
    Location
    Florida
    Posts
    4,382

    Default

    --- edited ...........................

    Ok, with high power 808 pump diodes available, TECs abundant, and the KTP / vanadate hybrid crystals with the HR and OC grown/ deposited already on them, pre assembled and readily available how hard can it be to build a DIY 1 watt green. (While we're waiting on high power DI diodes to develop)?
    Apparently most 532 cores (possibly even the 500mw ones) dont even use a focusing lens between the 808 pump and the crystal.
    Thoughts?

    Click image for larger version. 

Name:	808 Vanadate KTP assy.jpg 
Views:	216 
Size:	186.4 KB 
ID:	35444

    Click image for larger version. 

Name:	Roithner hybrid crystals 532.jpg 
Views:	80 
Size:	110.7 KB 
ID:	35445
    Last edited by steve-o; 11-01-2012 at 04:33.

  3. #3
    Join Date
    Feb 2011
    Location
    New Hampshire
    Posts
    3,513

    Default

    OK,
    I'm interested if there is a source of these components readily available and if the PO is on the order of 1W. I saw your edited video (it wasn't so bad) and it looked as if you had opened up a typical 100mW or there about, laser pointer. Temperature control, IR filtering and even knife edging for increased power are relatively easy, but doing all of that for an assembly of 10 of these hybrid diode/chip/doublers to get to 1W is not very competitive with a 1W turn key system.

    I am currently green starved. The red and blue are now EASY to assemble into high beam quality multi-watt modules (sucha problem don't ya know). The green continues to hover around $1/mW and the direct diodes are WAY WAY more than that. So.... what have you got?

  4. #4
    Join Date
    Jan 2007
    Location
    Florida
    Posts
    4,382

    Default

    O-like has a 500mw pointers , no TEC or fancy stuff I'm sure. There are high power hybrid crystals that appear on ebay every so often. I have my eye on one now as well as multi watt 808nm pump diodes, some even fiber fed, so they're out there. I'm just waiting to get ballsy enough to order this stuff.. it's a chance.. but life is a chance.. now I'm waiting on Steve to chime in and tell me "no way" .. what-say prof ?
    The one I had in the vid was a 150mw, putting out around 180 w/ optics removed (right out of the crystal) .
    Thanks for liking (or whatever) my nutty-goofy vid .. it seemed ok when I was making it while having glasses of wine lol ..

  5. #5
    mixedgas's Avatar
    mixedgas is online now 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
    9,108

    Default

    The first limit is how well you can control the diode temperature to match the pump wavelength to the adsorption.

    The second limit is when the hybrid cracks from physical limits to possible cooling. Submerge the sucker in some very clear inert fluid, , no one else has tried that.
    Water probably a option for short life of coatings, whatever they used to use for projection CRTs and medical lasers is probably better, but slimy and a bit toxic.

    The third limit is optical damage.

    I have not blown up a modern one. So I have no idea how high you can go.

    I'll tell you this much, doing a 2 mirror external cavity or a three mirror ring is no where near as hard as you might thimk. Heck, compared to a Argon they can almost self align. This is because they have whopping gain compared to gas, You might be happier with the results.

    I mean if the Asians can epoxy them together without mirror mounts, you can do quite well with the mech skills you have !!

    I hear MgO based hybrids make you wish you bought KTP hybrids when you overdrive em, but that is a rumor.

    Just make sure the diode you buy is really 808 or close thereof. I've gotten burned lately, by diodes that were 820 and marked 808.

    I'd track down Junktronix. Junktronix may be a bit more expensive then Ebay, but he can measure the center frequency....

    Steve-O, send me a email and I'll send you a 1 watt design paper I cant post here. Nothing Top Sekret Lotus Eater Special Merlin, just copyright issues. You get it workin, and you can pass on the Knowledge. Or better yet, let me know and we'll produce US made lasers and sell em.

    Watch your eyes with the 808. I work with femtosecond 800 at 4 watts every day, and its not a picnic. Because the work one is superpulsed, it has the pretty, but weak red glow when it hits things, but the amount of power there is deceptive and dangerous.

    For aligning 800, I just use a CCD B-W video camera and a 29$ USB frame grabber. Cheap, maybe 45$ to make a aligner-cam if you shop the bay. Far less if you have a old NTSC tv around. Saves me from stickin my head in those tight optical places. Make sure the lens is good for close up, and has a adjustable iris. The ones that stores use to see if cashiers are taking from the till are cheap on Ebay and work great.

    Steve
    Last edited by mixedgas; 11-01-2012 at 14:53.

  6. #6
    Join Date
    Jan 2007
    Location
    Florida
    Posts
    4,382

    Default

    Yeah the ccd cam is my 1st choice for working/ designing one of these things.. Thanks Man for the info.. Mr.FAQ -- Sam's Choice !! Yo da Main ! Ok-- I mean, isn't there a happy medium between a 40W laserscope (for 4K) and a 4W CNI or whatever (for 4K) ?? Yes 808 for the center freq-- Junktronix - he is one of the ones on the main radar I was speaking of -- PM incoming .. Thx dude ..

  7. #7
    Join Date
    Feb 2011
    Location
    New Hampshire
    Posts
    3,513

    Default

    I'm in. But don't just build a 200mw toy. It's OK to use less expensive parts to learn. However, once you have worked Steve's design out then SCALE IT UP. Steve is also right re the external cavity with a high gain system; it isn't that hard and half the fun once you start to see emission is dialing it in.

    I've aligned a LS 1064 just looking at fried dust (thanks Jon), but I doubt the 800nm diode is hot enough. What about those security cams sold at Wmart or the other BB stores? Can you just plug them into a comp monitor?

    Steve I need a 5W green. Can you help me out.

  8. #8
    Join Date
    Jan 2007
    Location
    Florida
    Posts
    4,382

    Default

    Well, I don't know about 5W, that's kind of ambitious at this point.. I was going to try for 1W first. (unless you were writing to Steve R. - you have to specify which Steve you're writing to )

  9. #9
    Join Date
    Feb 2011
    Location
    New Hampshire
    Posts
    3,513

    Default

    Nope. Not Steve R. You dude and I am thinking about 5W because that is the range,2-8W, where there is really no solution. Unless you can spend really big money there are no alternatives. The blue and red are here already and are not relatively expensive. I also believe that once you cross the 1W threshold the design will probably not change significantly, just the size of the components. In some cases such as the optics I suspect that the specific component won't change at all. I would be willing to help if your interested.

  10. #10
    Join Date
    Jun 2009
    Location
    Nebraska
    Posts
    168

    Default

    Quote Originally Posted by planters View Post
    Nope. Not Steve R. You dude and I am thinking about 5W because that is the range,2-8W, where there is really no solution. Unless you can spend really big money there are no alternatives. The blue and red are here already and are not relatively expensive. I also believe that once you cross the 1W threshold the design will probably not change significantly, just the size of the components. In some cases such as the optics I suspect that the specific component won't change at all. I would be willing to help if your interested.
    Just scaling it up sounds nice, but then power consumption doesn't scale in the same way. It will take more power to achieve the same behavior. Just keeping the larger optics temp controlled is more difficult because of size and poor thermal properties like conductivity, so then your NLO optics have to change shape and dimensions which re-arranges the design of the pump beam.

    Scaling sounds nice, but the limitations of your hardware and components don't scale the same with just "size".


Posting Permissions

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