Page 1 of 3 123 LastLast
Results 1 to 10 of 22

Thread: Why not 550nm Green ?

  1. #1
    Join Date
    Nov 2009
    Location
    Ølstykke Denmark
    Posts
    28

    Default Why not 550nm Green ?

    Why can we not make an 550nm green laser, for visual laser shows, this wavelenght should be optimal for the human eye !
    Then these wavelenghts should not be so strong !
    Panolin Quickshow 2 and Beyond whit 2 FB3 controllers, full RGB
    Feel free to join my Laser freak group on Facebook
    http://www.facebook.com/#/group.php?gid=53680012853

  2. #2
    Join Date
    Sep 2006
    Location
    Netherlands
    Posts
    1,425

    Default

    In short ?

    Because the advantage of enhanced visibility is totally outweighed by the disadvantage of the cost of making a specific wavelength laser.

    Due to its small market, the laserdisplay-industry tends to end up with lasers that were specifically developed for other purposes.

  3. #3
    Join Date
    Dec 2006
    Location
    New Jersey
    Posts
    247

    Talking

    Quote Originally Posted by Kenneth Hansen View Post
    Why can we not make an 550nm green laser, for visual laser shows, this wavelenght should be optimal for the human eye !
    Then these wavelenghts should not be so strong !
    Actualy the peak of the photopic curve (eye response) occurs at 555nm.... Maybe that is the better wavelength to your point... However +/- 3nm isn't oing to buy you much at the position on the curve.

    Always good to ask questions and pose a challenge

  4. #4
    Join Date
    Jan 2008
    Location
    Stockholm, Sweden
    Posts
    799

    Default

    Making green light is hard enough as it is with DPSS technology. You are not free to pick your wavelength with this type of laser as you need to find an ion with emission in the right place.

    Besides, I don't think 550 nm makes a very nice green color - it's too far to the yellow.

  5. #5
    Join Date
    Dec 2008
    Posts
    6

    Default There is a difference in perceived brightness in the dark

    Another thing to consider is that in dark your eyes are more sensitive to around 500nm's, and really.. Who does laser shows in bright conditions?

    --Hydro15

  6. #6
    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
    9,437

    Default

    Quote Originally Posted by hydrogenman15 View Post
    Another thing to consider is that in dark your eyes are more sensitive to around 500nm's, and really.. Who does laser shows in bright conditions?

    --Hydro15
    With LED walls multiplying at a insane rate, more often then you might think.

    Peace,

    Steve

  7. #7
    Join Date
    Oct 2009
    Location
    Eindhoven, The Netherlands
    Posts
    921

    Default

    Quote Originally Posted by -bart- View Post
    In short ?

    Due to its small market, the laserdisplay-industry tends to end up with lasers that were specifically developed for other purposes.
    I dare to question that with 445nm blue, since video projection is also a display purpose, and 445nm blue was chosen for its visibility by the human eye.

    In contrast to the 532 we got 'for free' with 1064nm YAGs or 660nm which was chosen because of better interaction with DVD substrates.

  8. #8
    Join Date
    Sep 2006
    Location
    Netherlands
    Posts
    1,425

    Default

    True, but even 445 is a trade-off between visibility and achieved color-space.

    Besides that, there are lots of criteria that make a laser successful or even suitable for laserdisplay.
    Is solid state?,is it portable?, is it scalable?, can it be directly modulated? , is it power efficient?, lifetime ? maintenance ? weight ? toxicity of materials?, price? beamspecs?
    Good visibility is just one of them.

    Was the dvd diode specifically 'chosen' to match the substrate of a dvd ?
    OR
    Was the dvd substrate developed to match a laser diode that could be easily mass produced ?

  9. #9
    Join Date
    Aug 2010
    Location
    Riverside, California, USA
    Posts
    14

    Default

    our scoptic vision is sub 500nm. which is where/when we use our lasers.


    michael.

  10. #10
    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
    9,437

    Default

    [QUOTE=Stoney3K;173405]I dare to question that with 445nm blue, since video projection is also a display purpose, and 445nm blue was chosen for its visibility by the human eye.

    Your close,
    We got 445 because 460-480 was unreachable in the development lab at the time.

    Steve

Posting Permissions

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