Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Optics : Polygonal mirrors

  1. Jul 1, 2009 #1
    Hello Forum , i have a Polygonal mirror with 6 facets of mirrors , i am working in a project for a scan system without lens . I would like to ask you about a document or books to find the formulas of : Scan Angle,The distance between the polygon and the scan plane in a system without a scan lens,The total length of the scan line in the scan plane.
    Thank you in advance,
  2. jcsd
  3. Jul 1, 2009 #2

    Andy Resnick

    User Avatar
    Science Advisor
    Education Advisor
    2016 Award

    I don't know of a succinct reference- maybe there's an optical design book in a library near you with a relevant chapter. All I have is a few sections in "Building Electro-Optical Systems", by Phil Hobbs.

    He treats the problem purely geometrically- a 6-facet mirror gives a total angular scan of 4*pi/6, and the beam scans at constant angular frequency.

    Moreover, he notes that becasue the rotation axis does not pass through a surface, the scanned beam translates as well as pivots during a line. So-called f-[tex]\theta[/tex] lenses are used to convert constant angular velocity scans to constant linear velocity scans by use of distortion.
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook