Results 1 to 2 of 2

Thread: Which Dichro

  1. #1
    Join Date
    Sep 2007
    Location
    Essex, England
    Posts
    798

    Default Which Dichro

    Hi all, Marconi kindly pointed me to these but how do I know which one reflects and which one lets through.....http://www.edmundoptics.com/onlineca...productID=2433

    I guess if it says • FILTER 45DEG DICHROIC BLUE 25MM D The that one will bounce the blue but allow teh rest of the beams through, is that correct?

    Then what does this mean...

    Red 615nm ± 15nm: Rabs= 50%
    640-750nm: Rave> 98%
    Blue 510nm ± 15nm: Rabs= 50%
    400-475nm: Rave> 98%
    Green 535nm ± 15nm: Rmax> 98%
    FWHM (R%): 65nm ± 15nm

    1) Is there a way of working out which order to mix the colours so you have minimal loss?
    2) Is loss proportinate to teh power of the laser....e.g. If I had 100 mw and 1000 mw, would I lose 30mw from both or would I lose 30 from the 100 and 300 form the 1000?
    I'm rubbish @ maths
    Graham






  2. #2
    Join Date
    Apr 2007
    Location
    Toronto Canada
    Posts
    1,120

    Default

    The BLUE will reflect blue and pass red and green
    The GREEN will reflect green and pass blue and red
    The RED will reflect red and pass green and blue.

    Red 615nm ± 15nm: Rabs= 50% (Will give you 50% reflection of those waveleghts)
    640-750nm: Rave> 98% (Will give you 98% reflection of those waveleghts)
    Blue 510nm ± 15nm: Rabs= 50% (Will give you 50% reflection of those waveleghts)
    400-475nm: Rave> 98% (Will give you 98% reflection of those waveleghts)
    Green
    535nm ± 15nm: Rmax> 98% (Will give you 98% reflection of those waveleghts)
    FWHM (R%): 65nm ± 15nm
    Normally Green is the cheapest and most powerful (get as much green as you can afford) in RGB projector so it goes to the back of the chain. Then
    goes red as second most expensive one. And then goes blue as most expensive. You need to preserve as much blue as possible. Green will loose about 20mw and red will loose about 10mw and blue only 5mw on the way to galvos. (I calculate based on 500red 400green 200blue)
    I hired an Italian guy to do my wires. Now they look like spaghetti!

Posting Permissions

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