Forum Rule: Always post complete source code & details to reproduce any issue!
Results 1 to 16 of 16

Thread: diffuser materials - anyone here tried any?

  1. #1
    Senior Member
    Join Date
    Oct 2013
    Posts
    116

    diffuser materials - anyone here tried any?

    I'd like to diffuse my WS2812b strip lighting somewhat, but I still want to be able to distinguish one "pixel" from another. Essentially, I want them to blend/overlap somewhat at the edges, so if you put red next to blue, you'd see a red diffuse spot, a blue diffuse spot, and a red-purple-blue gradient between them. I believe that this should be tune-able with a good diffuser material by varying the distance between the LED and the diffuser. Anyway, I'm looking at:

    http://www.professionalplastics.com/MakrolonLumenXT

    http://www.aliexpress.com/item/300mm...254222381.html

    Anyone have experience with either of those or suggestions for other materials to consider? This will end up covering about 5000 LEDs over a roughly 8' by 15' area. ( Project thread here:
    http://forum.pjrc.com/threads/24370-...-and-a-answers )

  2. #2
    Senior Member
    Join Date
    Jan 2013
    Posts
    966
    I'd try it out.
    Usually companies that sell these materials have a little sampler with a variety of their materials so you can pick the one that suits your application best.

  3. #3
    Senior Member
    Join Date
    Jun 2013
    Location
    Torrance CA
    Posts
    415
    I've had pretty good success using this stuff from Inventables

    https://www.inventables.com/technolo...ser-film-rolls

    they also sell the diffuser in individual sheets and as plastic powder (if you own an injection molder).

  4. #4
    Senior Member
    Join Date
    Oct 2013
    Posts
    116
    Thanks for the replies and advice. I've asked for samples from the two links in my OP, and have ordered a sheet of the .007" material from the Inventables link provided by potatotron. I'll post some comparisons back here once I get some samples. I'm not sure how easy it will be to get a sample from the aliexpress shop, but I guess we'll see

  5. #5
    Senior Member
    Join Date
    Sep 2013
    Location
    Hamburg, Germany
    Posts
    894
    I've had good results with simple transparent paper that is otherwise used for technical drawings.

  6. #6
    Senior Member
    Join Date
    Oct 2013
    Posts
    116
    Update:

    I've tested the materials from the aliexpress vendor as well as the film from inventibles (no pictures yet - sorry). I suspect they're both using the same basic compound as they have very similar characteristics. The material from aliexpress is much thicker and able to diffuse very effectively even from a couple millimeters away. Of course at that distance, there's still a significant hotspot, but a very complete-looking diffusion effect can be achieved at only around 3cm away.

    In short, I'm very happy with this one:
    http://www.aliexpress.com/item/300mm...254222381.html

  7. #7
    Senior Member
    Join Date
    Jan 2013
    Posts
    966
    Thanks for posting what worked!
    Of course we expect some nice imagery or video when your project approches a certain level of functionality and completion ;-)

  8. #8
    Senior Member
    Join Date
    Oct 2013
    Location
    Rogersville MO
    Posts
    253
    I have had interesting results with white PEX tubing.

  9. #9
    Member neep's Avatar
    Join Date
    Jan 2013
    Location
    Amsterdam, NL
    Posts
    82
    I've been using old Fuji slide film canisters that I still had laying around. I believe it's polypropylene, I use it for my LED staffs as they fit nicely around the whole construct. I then tape them together using Scotch tape, and cover it with transparant shrink-wrap for a strong finish. You can sometimes find these old film canisters on Ebay.

  10. #10
    Senior Member
    Join Date
    Oct 2013
    Posts
    116
    Well, it turns out that trying to take pictures of LEDs with a point-and-shoot in an otherwise pitch-black room is VERY DIFFICULT! I'll try to set up some test samples in different light and see if that helps.

    I tried "milky" or "frosted" looking plastic, but that blocks a lot of light and doesn't have the impressive diffusion characteristics of some of these newer materials. At 5cm distance from the 30leds/meter strip, the light appears completely uniform. With the diffusing material in direct contact with the strip, it accomplishes my goal of making the Red, green, and blue "sub pixels" invisible while also reducing the hot-spot effect. If you want to diffuse as much as possible in as little room as possible, these materials are hard to beat!

  11. #11
    Senior Member PaulStoffregen's Avatar
    Join Date
    Nov 2012
    Posts
    22,497
    Yup. I had to buy a special filter for my camcorder to make that OctoWS2811 video.

  12. #12
    Member neep's Avatar
    Join Date
    Jan 2013
    Location
    Amsterdam, NL
    Posts
    82
    I'd like to revive this thread a bit since I'm preparing for a new LED project. What I've been using so far as diffuser material on another LED project are these old slide film canisters which are great for that purpose, but now I need something that is bendable and more or less flat at the same time. In particular I want to be able to make "wearable" segments of addressable LED strips, each Teensy controlled.

    Anyone have any ideas on diffuser material that may be suitable for that?
    Last edited by neep; 02-17-2014 at 03:36 PM.

  13. #13
    Senior Member
    Join Date
    Sep 2013
    Location
    Hamburg, Germany
    Posts
    894
    Materials (untested!) that come to mind are
    • reusable silicone baking "paper", I've seen brands that are white and almost clear
    • 2-component silicone that you can use to pour a thin sheet or any shape you like (maybe add glass bubbles that are usually used to stretch epoxy resin)

  14. #14
    Senior Member
    Join Date
    Oct 2013
    Posts
    116
    This material has great diffusion properties for its thickness. The thinner of the two is obviously more flexible, but will provide less diffusion:
    https://www.inventables.com/technolo...ser-film-rolls

    However, this isn't something you'd want to feel in direct contact w/ the skin.. if that's part of your design, I like where christoph was headed w/ 2-part silicone.... you could even create a mold if you needed reproducability, and you might be able to use the powdered diffuser additive sold @ the above link (same material they mix with polyethylene or other plastics to make diffuser sheets)

  15. #15
    Member neep's Avatar
    Join Date
    Jan 2013
    Location
    Amsterdam, NL
    Posts
    82
    Thanks for the tips and the links. I think something like the rolls is probably best to start with. Easy to just cut into the size I need without much work. I'm going to see if I can get this shipped to Europe. Not sure how I am going to have this connect to the body yet. I may put something underneath so as to not have direct contact with the skin.
    Last edited by neep; 02-18-2014 at 02:24 PM.

  16. #16
    Senior Member+ MichaelMeissner's Avatar
    Join Date
    Nov 2012
    Location
    Ayer Massachussetts
    Posts
    3,831
    If you go to the big photo stores, they sell various flash modifiers to soften light. Some diffusers are hard plastic, but many are flexible. You could buy some, and just cut them up. For example: http://www.bhphotovideo.com/c/produc...i_Softbox.html or http://www.bhphotovideo.com/c/produc...non_Nikon.html.

Posting Permissions

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