Difference between DOE and Zone Plate

Discussion in 'Camera Building, Repairs & Modification' started by Mustafa Umut Sarac, Jul 2, 2007.

  1. Mustafa Umut Sarac

    Mustafa Umut Sarac Member

    Messages:
    4,574
    Joined:
    Oct 29, 2006
    Location:
    İstanbul
    Shooter:
    35mm RF
    Can anyone explain ;
    what are the differences between DOE and zone plate ?

    best ,

    mustafa umut sarac
     
  2. Ole

    Ole Moderator Staff Member Moderator

    Messages:
    9,281
    Joined:
    Sep 9, 2002
    Location:
    Bergen, Norw
    Shooter:
    Large Format
    In theory NONE.

    But just like an overly large pinhole won't form a good image on its own, and does a great job of "tightening up" an image when it's inserted in the correct place as an aperture; so a Diffractive Optical Element does a great job as a "super-high dispersion element" in the right place in a complex lens designed with just such an element. A DOE has very little thickness so the refractive index is "virtual", but the dispersion is very high and easily controllable.
     
  3. Mustafa Umut Sarac

    Mustafa Umut Sarac Member

    Messages:
    4,574
    Joined:
    Oct 29, 2006
    Location:
    İstanbul
    Shooter:
    35mm RF
    Ole , I am understanding from your text that doe is zone plate ? I read a patent which describes a achromatic lens made by two doe or as you said with two zoneplates. Is it possible to form other negative curve lens elements with doe - zone plate - couples ?
    The most important question , is it possible to form a complex lens only with multilayer zoneplates with the quality of professional lens ? a lens for to cover 1,5 square meters wide glass negative ?