Results 1 to 6 of 6

Thread: IF you can do it with a lens you can do it with a mirror

  1. #1
    Join Date
    Nov 2008
    Location
    Cleveland Ohio
    Posts
    2,599

    Default IF you can do it with a lens you can do it with a mirror

    Had never thought about it but here is a mirror based beam expander. Bet this could be the basis for a beam brush too with one moving part. Complex bugger

    https://wavelength-oe.com/wp-content...ation-Note.pdf
    https://www.edmundoptics.com/f/monol...-mark-I/38639/

  2. #2
    Join Date
    Oct 2012
    Location
    Germany
    Posts
    1,478

    Default

    ... some time ago I've tested "beam-shaping" of the blue diodes with one or two concave mirrors -- it works and and has much less energy loss than with lenses ... even, if the lenses would have AR coatings

    Viktor
    Aufruf zum Projekt "Müll-freie Meere" - https://reprap.org/forum/list.php?426
    Call for the project "garbage-free seas" - https://reprap.org/forum/list.php?425

  3. #3
    Join Date
    Nov 2008
    Location
    Cleveland Ohio
    Posts
    2,599

    Default

    Quote Originally Posted by VDX View Post
    ... some time ago I've tested "beam-shaping" of the blue diodes with one or two concave mirrors -- it works and and has much less energy loss than with lenses ... even, if the lenses would have AR coatings

    Viktor
    problem is making the mirrors. Though with 3d printing or cnc it is much easier now. Then just silver over the surface.
    Nice thing is you can build in abberation corrections and if you size it right it can trim the beam edges for you too without a pinhole. Now add a pinhole at the end and wow what a device. Other thing is it’s apo from the start for all wavelengths!
    add this just before the scanners.

    let me explain better. It’s one mirror in one axis and the other in the other. To cut a single mirror for both would be hard but to make a trough for one axis is not hard. Ok so not a true beam expander or beam brush but I just thought about it and this type of device we could fabricate. Making a proper set of 3d mirrors would be hard. In fact we could use a screw to flexure the mirrors a little for some adjustment.
    Last edited by kecked; 05-27-2021 at 04:04.

  4. #4
    Join Date
    Oct 2012
    Location
    Germany
    Posts
    1,478

    Default

    ... my concave mirrors were from my CO2-lasercutter-development around 30 years ago, made from glass, 20mm in diameter and 50mm, 75mm or 100mm FL.

    For testing with cheaper ones you can go away with the "cosmetic" mirrors ... have some with 50mm to 120mm diameter ...

    Viktor
    Aufruf zum Projekt "Müll-freie Meere" - https://reprap.org/forum/list.php?426
    Call for the project "garbage-free seas" - https://reprap.org/forum/list.php?425

  5. #5
    Join Date
    Jun 2009
    Location
    Mesa, AZ
    Posts
    1,277

    Default

    Here's an all reflective focusing element from 1967 by Spacerays. I think the needle on the output side is to indicate focal length.
    Attached Thumbnails Attached Thumbnails Spacerays Lens.jpg  

    Spacerays Lens Parts.jpg  

    LFBGJan67Spacerays.jpg  


  6. #6
    Join Date
    Nov 2008
    Location
    Cleveland Ohio
    Posts
    2,599

    Default

    Quote Originally Posted by Eidetic View Post
    Here's an all reflective focusing element from 1967 by Spacerays. I think the needle on the output side is to indicate focal length.
    I wonder why we don’t see more reflective elements these days. We can manufacture so much easier now.

Posting Permissions

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