Page 3 of 3 FirstFirst 123
Results 21 to 29 of 29

Thread: RGB theoretical layout (cause I'm bored)

  1. #21
    Join Date
    May 2007
    Location
    Milwaukee WI
    Posts
    1,355

    Default

    Well Ray - the next time you are in the states - come up to the beer capital - Milwaukee!

    I am sure there are a few places that wont necessarily change your mind - but will at least give you a better idea of what we're capable of. Don't base your opinions on the macro brews that you may have seen - or tasted for that matter

    -Max

  2. #22
    Join Date
    Jan 2008
    Location
    Stockholm, Sweden
    Posts
    799

    Default

    It's not all that easy to find beer from small American breweries in Sweden, especially so because there's a monopoly on alcoholic beverage sales to consumers. Only the state-owned company called "Systembolaget" is allowed to sell anything with more than 3.5% alcohol in it. This season they did manage to find one nice American beer from Left Hand called milk stout. It's great! It's apparently becoming pretty popular too, so hopefully us Swedes will see more American beer here soon, as people start to realize. Not that shipping beer halfway around the globe is great for the environment, but what the hell... If I can't have a good beer, what's the point of living anyway?

    Quote Originally Posted by mliptack View Post
    But if you guys ever come to Milwaukee - I will take you out for a night at the Lakefront Brewery! $5 tour that comes with 6 beers - You just cant beat that. Lakefront brewery makes some of my favorite beers. Wow this thread is way off topic.
    I'm coming!

    At least we're in the lounge...

  3. #23
    Join Date
    Sep 2006
    Location
    St. Louis, MO - US
    Posts
    83

    Default

    Quote Originally Posted by mliptack
    Wow this thread is way off topic.
    No shit! I was thinking about that a few hours ago when I was at Home Depot going over this thread in memory. Anyways.....

    In regards to beam polarization, using a PBS cube with two square modules, does one have to be rotated 90 or 180 degrees or can they both lay flat on the same mounting plate?

    The modules I had in mind are square and not round like a beer can.

  4. #24
    Join Date
    Jan 2006
    Location
    Charleston, SC
    Posts
    2,147,489,446

    Cool

    As much as I'd love to discuss beer some more, godfrey's question is a good one.

    The diode inside that module is round, godfrey. So it's easy to rotate it to get the polarization angle correct. However, if you purchase the modules pre-assembled and you don't want to mess around with taking them apart, then you can always rotate one 90 degrees.

    The polarization of the two diodes need to be 90 degrees apart. Which, if you think about it, is the farthest they can be apart. Because a vertically polarized beam vibrates up *and* down, while horizontally polarized vibrates right *and left. So if you start with them exactly aligned and begin rotating one, when you get to 90 degrees you are perpendicular and that's as far apart as you can get. If you keep rotating, you get to 91 degrees, which is the same as 89 degrees from the other way.... Get it?

    The other thing to remember is that you need to know which laser is vertically polarized and which one is horizontally polarized so you can align the cube properly. If you get them mixed up, the cube will reject nearly all the light and you'll have no output.

    Adam

  5. #25
    Join Date
    Jan 2008
    Location
    Stockholm, Sweden
    Posts
    799

    Default

    Quote Originally Posted by buffo View Post
    The other thing to remember is that you need to know which laser is vertically polarized and which one is horizontally polarized so you can align the cube properly. If you get them mixed up, the cube will reject nearly all the light and you'll have no output.
    What happens if you get them mixed up is that you'll have the light coming out of the other side of the cube. Then you either exchange the lasers or just rotate the whole mounting plate 90°.

    If you mount the cube incorrectly you can end up having the lasers shining into each other which, while somewhat comical, can be very bad.

    That polarization thingy is tricky stuff though. As it involves quantum mechanics it is very counter-intuitive and will make your head spin. Luckily, for our applications, simply describing polarization as up-down/left-right is sufficient to understand how to use a PBS cube.

    Do these pre-assembled modules always come with a polarization 0 or 90° to the base? I hope so, because it seems like a pain in the ass to mount them at any other angle.

  6. #26
    Join Date
    Sep 2006
    Location
    St. Louis, MO - US
    Posts
    83

    Default

    Quote Originally Posted by tocket
    Do these pre-assembled modules always come with a polarization 0 or 90° to the base? I hope so, because it seems like a pain in the ass to mount them at any other angle.
    This is a question I will have to ask Ava from CNI tonight.

    Ideally, I wanted the modules mounted next to one another, not have one or two of them sitting sideways on a secondary plate. While this is not difficult to have machined, it will significantly change the aperture height from the others which is what I'm trying to avoid.


    I usually get e-mail responses back from her between 12:00 and 2:00 AM. I'll let you guys know.

  7. #27
    Join Date
    Jul 2005
    Location
    Flying over a town near you
    Posts
    1,404

    Default

    The lasever 473nm laser I got off e-bay was a test subject for exactly this. I took the head apart from the base and discovered ,that with a little steady handedness,I could seperate the laser cylinder from it's 90* angle bracket and make my own mount for it. The reason for this is that the TEC has a hole through it for , well, rotation to adjust polorisation of the beam. I attempted the mixing with another of my lasers and found it to be extremely easy to get it right This option sure beat the sox off me trying to create and machine a mount at X degrees. It was the big U series and I got a good deal on it , so I wanted to know.
    You are the only one that can make your dreams come true....and the only one that can stop them...A.M. Dietrich

  8. #28
    Join Date
    Sep 2006
    Location
    St. Louis, MO - US
    Posts
    83

    Default

    I however am not looking at spending upwards of $16,500 on laser heads to have to take them apart.....but if I had no choice then sure...


    To answer the question on ordering a module with a specific degree of rotation...the answer is yes. You must specify this when ordering though. This of course was CNI - but I am sure other manufactures would be happy to assist you with your needs.


    Phil

  9. #29
    Join Date
    Jan 2006
    Location
    Charleston, SC
    Posts
    2,147,489,446

    Cool

    Quote Originally Posted by tocket View Post
    What happens if you get them mixed up is that you'll have the light coming out of the other side of the cube.
    Actually, it depends on the orientation of the cube. If the polarization is off, part of the beam might shoot straight through, or part of it might be reflected and shoot out one of the other faces.
    Then you either exchange the lasers or just rotate the whole mounting plate 90°.
    That would work if you had the polarization exactly wrong. But more common is the case where neither laser is perfectly horizontal or vertical, but rather some angle in-between. Then you get *some* light in the output, while the rest is wasted (rejected) by the cube. Then it's a real pain to get them mounted correctly.
    If you mount the cube incorrectly you can end up having the lasers shining into each other which, while somewhat comical, can be very bad.
    Yeah, like kill your diode bad! You also need to be mindful of back-reflection off the cube face. A few members here have killed their Maxyz modules by messing around with the PBS cube alignment while the power was turned up high. (Not applicable to DPSS lasers, but this is certainly a risk with direct injection diodes.)
    Luckily, for our applications, simply describing polarization as up-down/left-right is sufficient to understand how to use a PBS cube.
    Yep. All the more simple if you can get the manufacturer to label the lasers as up-down or left-right before they send them to you. That makes it *very* easy to set up.
    Do these pre-assembled modules always come with a polarization 0 or 90° to the base?
    Saddly, no. But as Mike mentioned above, it is possible to rotate the laser within the mount. Still, I'd rather have it done for me at the factory. It's always a good idea to specify this fact, however.

    Adam

Posting Permissions

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