• State
  • Locked Locked
  • Replies 3 replies
  • Subscribers 28 subscribers
  • Views 1403 views
  • Users 0 members are here
Support feedback
Options
Options
Related

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

Can the light crafter 4500 be modified to project patterns at shorter distances?

Andres Marrugo
Prodigy 20 points

I'm thinking in buying a light crafter 4500 dlp for structured light 3D reconstruction. However, the objects I need to scan are relatively small (200 micron height, 5x5 mm lateral size). I was thinking about using phase shifting, but I need to get as many fringes per mm as posible in order to be able to measure 200 microns in height. Is this possible?

  • 0
    TI__Mastermind 30600 points
    Andres,

    There is some specific discussion of your question in section 5.2.3 Build Envelope And Voxel Resolution in the user's guide: www.ti.com/lit/pdf/dlpu025

    If that doesn't meet your requirements, you'll need a new optical design on the EVM to accomplish your goal. Take a look at some of our design network partners and see if they offer anything that better fits your application than the standard LCr4500. www.ti.com/.../solutions-services.page

    Hope this helps,
    Paul
  • 0 in reply to Paul Goedeke
    Prodigy 20 points

    Ok, I get it that I can add shims to the projection optics to shorten the minimum projection distance. From the the links you gave me I ended up looking at the TIDA-00293 DLP 3D Printer reference design, because for the 3D printer application the projection resolution must also increase as in my case. I am left with several additional questions:

    1. Can I add shims with whatever thickness to modify projection distance?
    2. I haven't been able to find specific information regarding the optics of the LCr4500, just the minimum and maximum projection distance. I asume it is a zoom objective (focal length range? size? aperture?) I see that Wintech Digital Systems has built a custom projection objective (or modified it) to alter projection distance. Can one do this in a similar way? 
    3. I would like to modify the optics assembly so that my LCr4500 projection optics is able to use any standard c-mount objective lens. Is this possible?

    Thanks.

  • 0 in reply to Andres Marrugo
    TI__Mastermind 30600 points
    You'll have to play with different thickness shims to see the results. In other threads, users have had difficulties with additional optical issues such as aberrations when they added shims. There is probably a limit to how thick you can shim.

    In another thread, it was suggested to add a converging/positive lens to the front of the lightcrafter. That may be worth trying as well:
    e2e.ti.com/.../305041

    As for the optics, look at the LCr4500 user's guide: www.ti.com/lit/dlpu011, page 11 shows a table of the light engine specs.

    I'm not aware of anyone who has modified the stock LCr4500 to accept c-mount lenses. I would look at the DLP design network partners and see if they have any solutions that might help you. www.ti.com/.../solutions-services.page