Page 1 of 2 12 LastLast
Results 1 to 10 of 11

Thread: Advice needed for RGB build

  1. #1
    Join Date
    Feb 2009
    Location
    Benidorm, Spain.
    Posts
    144

    Question Advice needed for RGB build

    I'm thinking of building my first RGB for doing beam shows and graphics, but I'm not sure about which beam specs and red wavelength I should be looking for to get a good end result without the costs shooting through the roof.
    I already have an XJ-A140 445nm blue diode in an Aixiz module that I want to use, if possible, and my idea at the moment is to aim for something in the range of 1 to 1,5 W total power.

    Domingo.

  2. #2
    Join Date
    Nov 2010
    Location
    Denmark
    Posts
    244

    Default

    Quote Originally Posted by DPSS View Post
    I'm thinking of building my first RGB for doing beam shows and graphics, but I'm not sure about which beam specs and red wavelength I should be looking for to get a good end result without the costs shooting through the roof.
    I already have an XJ-A140 445nm blue diode in an Aixiz module that I want to use, if possible, and my idea at the moment is to aim for something in the range of 1 to 1,5 W total power.

    Domingo.
    What is your budget?

    /Thomas

  3. #3
    Join Date
    Feb 2009
    Location
    Benidorm, Spain.
    Posts
    144

    Default

    Hi Thomas,

    I haven't really got a fixed budget, but right now I'm thinking of spending a maximum of arround 800 to 1000 on the green and red modules.
    If it turns out not to be enough to get something I'm happy with, I'll probably just buy a green and wait untill I can afford the red (and maybe even a 473 blue sometime in the future ).

    Domingo.

  4. #4
    Join Date
    Oct 2010
    Location
    Athens, Greece
    Posts
    1,931

    Default

    a usefull info would be whether you prefer beams or graphics (could affect the choice of galvos and their cost)

    another piece of usefull info could be whether you are comfortable with making your own red modules or you will buy ready made ones

    i could say that since you go for a 1w total power, the 640nm HL6385DG red diodes (two or better three of them probably) will be a good and obvious choice. or, for a cheaper solution you could get a 660nm quad module

    so, something around 250mw-400mw blue (you can have more from the same module with no riscs, just by turning a pot on the power supply), 250mw green - analogue modulation and then dichros, mounts, a case, galvos etc etc

    800 to 1000 looks very feasible to me (maybe a bit extra for a dac and software, depending on what you purchase)
    "its called character briggs..."

  5. #5
    Join Date
    Feb 2009
    Location
    Benidorm, Spain.
    Posts
    144

    Default

    Hi LaNeK779,

    I like beams better really, but I want to build a projector that will do both beams and graphics at a good level.

    I do think of myself as a diy person, but in this case I've decided I'm going to buy the modules.

    As far as the rest of the components, I'm in the process of buying one of MisterWilling's USA version of Edison's projector case and I have dichros, mounts, galvos, an FB3 and Quickshow software, so I think I've got most of it covered.

    My main concern at the moment is about which wavelength of red to buy and which beam specs to look for that will match well with a green and a blue (preferably my 445nm) without costing me a fortune. As far as I understand (and that's probably not that much ) the less divergence the beams have and the better the match between the specs of the beams, the further away I will be able to project good graphics so, which would be a good compromise between wavelength, beam specs and price?

    Domingo.

  6. #6
    Join Date
    Oct 2010
    Location
    Athens, Greece
    Posts
    1,931

    Default

    so, you have most of the things already and all you need is a green and a red

    green divergence is close to the blue divergence and they are both high (around 1 - 1,2 mrad). red divergence is typically lower, unless you choose a module with a high divergence

    about prices, assuminng DIY (just for the examle) a 660nm 250 mw diode costs 4-5 usd and a 640nm 150mw diode costs 80-90 usd if you are lucky. the drawback is that 660 is dim and you need roughly twice the power compared to 640. The huge difference in bare diode prices reflects to the finished modules prices, too

    many people build their own reds here and they often make them commercialy available, so someone could actually make a red module for you and match the divergence with that of your blue and green
    "its called character briggs..."

  7. #7
    Join Date
    Dec 2008
    Location
    Southport, UK
    Posts
    2,746

    Default

    If you want good visible beams I would strongly advise that you go for <642nm.

    660nm might be half as bright as 640 when projecting graphics but my personal experience (my eyes?) says that it's much much less than half as visible when looking at beams. You need shit loads of 660 power to get good visible beams.

    However, probably the most cost effective thing to do is build/buy a 660 combiner module and upgrade the diodes as and when funds allow, at least this way you are only ditching a $5 diode each time you upgrade, rather than selling a full module for half of what you paid for it.
    http://img62.imageshack.us/img62/3985/laser.gif

    Doc's website

    The Health and Safety Act 1971

    Recklessly interfering with Darwins natural selection process, thereby extending the life cycle of dim-witted ignorami; thus perpetuating and magnifying the danger to us all, by enabling them to breed and walk amongst us, our children and loved ones.





  8. #8
    Join Date
    Jul 2009
    Location
    Dallas, Tx
    Posts
    372

    Default

    Quote Originally Posted by Doc View Post
    660nm might be half as bright as 640 when projecting graphics but my personal experience (my eyes?) says that it's much much less than half as visible when looking at beams. You need shit loads of 660 power to get good visible beams.
    I agree. I have 300mW 640 and 500mW 660 in my projector. They have a separate switch to turn them on and off. When I click the 660 on after the 640 I can barely tell a difference. SO I feel 660 is more like between 1/3-1/2 the brightness of 640. ALthough everyones eyes are different. I'm not against 660, but unless you build a multi diode setup (= or >4 diodes) your not going to get very strong beams and you would have to dial the 445 and 532 back pretty far.

  9. #9
    Join Date
    Feb 2009
    Location
    Benidorm, Spain.
    Posts
    144

    Default

    Yes, I've read many people here mention how much brighter 640 is than 660 and after checking the beam specs for the different red wavelengths on the Laserwave and CNI web pages y see the 640's also have the nearest specs to the green of all of them. So I think it's going to be 640.

    Given the money I'm thinking of spending though and after checking on Chroma how much 640 red I'd need to get a nice and white beam, I think I'll have to lower my power expectations a bit if I want to build a full RGB without waiting. Seems that for a 200mw 532nm, I'd need 300mw of 640nm and 160mw of 445nm. From what I've seen, 350mw of 640 will set me back around 600 euros so, after buying the green, that will have chewed up nearly the 800 to 1000 I mentioned earlier.
    Can you recommend anyone in particular that may be able to build me a good red module?

    I'll also have to make sure I can get my 445 to equal or similar specs before I buy anything else. I remember reading a thread started not long go about using a prism pair to correct the beam, but I haven't checked lately to see how it's going.

    Domingo.

  10. #10
    Join Date
    Oct 2010
    Location
    Athens, Greece
    Posts
    1,931

    Default

    in general, don't worry about the blue, you have much power sitting there, ready to be used. the prism pair works for many people and at the moment dave (that's a forum username) has many pairs left

    if you only need this unit for home entertainment and small events over at friends houses, i would suggest that a total power lower than 1w will be more than enough and will no get your eyes tired from specular reflections. even a small 100mw green will be more than enough for prolonged periods of usage

    so an analogue module with two 640 diodes is the thing for you in terms of red and a nice 150mw - 200mw analogue modulated green

    or you can get a quad red and wait till you can afford a bigger green
    "its called character briggs..."

Posting Permissions

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