Color Changing Fiber Optic Fabric




At about $150 a yard and with plenty of cutting limitations, fiber optic fabric on the market isn't the most accessible material. But with your own fiber optic filament, tulle, and LEDs, you can create your own in any shape for a fraction of the price.

Step 1: Materials

  • Tulle
  • .75mm fiber optic filament (see Step 2 for more details)
  • Addressable RGB LEDs
  • Sewable microcontroller of your choice (I used a Gemma)
  • Electrical tape
  • Mini rubber bands
  • Battery pack
  • Hair straightener
  • Heat shrink tubing (optional)

My cost was around $80 total: $15 for a 500 foot spool of fiber optics, $14 for a string of ~60 LEDs (I only needed ~18), $10 for the Gemma, $15 for the lithium battery, and $25 for fabric. Your mileage will vary depending on the length of your design, type of fabric, cost of LEDs, and availability of microcontrollers/battery packs.

The time to completion was around 30 hours, with at least 10 of those going towards weaving the fibers into the tulle.

Step 2: Crunch the Numbers

Fiber optics

The wider your fiber optic filament, the more light can pass through, and the sturdier the tube will be. I found .75mm to be perfect for weaving through tulle. Narrower filaments are cheaper and more flexible, but you'll require more of them to achieve the same glow.

I purchased a 500 foot spool and used about 350 feet in the creation of a long circle skirt, with my fibers laying .5cm - 1cm apart at the inner radius. To calculate roughly the amount of fiber you'll need, divide the width of your fabric by the amount of space you would like between filaments. Multiply this number by the length of your fabric plus 6 inches.

Cut your fibers about 6 inches longer than the length of your fabric. The excess will be bundled and attached to the LEDs.


You will need RGB LEDs to change the color of the fabric. You will also need to attach the fibers perpendicular to the light source, as shown in step 7, so NeoPixel strips are not the best candidate. Finally, if designing for clothing, you'll need something that lies relatively flat against the body. With all these parameters in mind, I chose individually addressable bulb-like LEDs connected by flexible wire.


The tulle and fiber optic combination in this Instructable is very translucent. The simplest way to add it to a project would be as a top layer over a more opaque fabric. When designing your project, remember that your fiber tips will all need to feed into a light source, and most light will be emitted at the opposite end. As long as you can design something with enough support for the lights and battery pack, and ensure that the fibers have a light source, you can create any size and shape you want!

Step 3: Straighten the Fibers

Most fiber optic filament will come tightly curled around a spool. Don't fret! A hair straightener works wonders. I did not have any success with an iron; heat from both sides seemed to be essential.

Cut your filaments to the desired length and bundle them together in groups of 5-10. Secure one end with a rubber band. Wet a washclosh slightly and use it to insulate the fibers as you slowly drag the straightener down the length of the filament. This will protect both your iron and the filaments from the direct heat. Repeat as many times as necessary to get the filaments nice and straight.

Step 4: Weave

By taking advantage of tulle's natural netting structure, you can keep your fibers in place while avoiding the need for hand sewing or individual channels.

Subdivide your tulle into halves, quarters, and so on to give yourself benchmarks for inserting fibers. It may be helpful to layer your tulle over a giant sheet of graph paper or pre-drawn parallel lines. Once you've guaranteed that the first few fibers are inserted perfectly parallel, they are easier to use as a guideline for the rest.

Begin weaving by poking a single strand of filament into the netting. Avoid tearing new holes; try to use the structure already there. Continue to weave the filament through the tulle every few inches. When weaving, favor one side of the fabric over the other; keeping the majority of your filament on one side will make it easier to sand later.

You may want to intersperse some fibers that are shorter than the full length of your fabric, too. This will spread specks of light more evenly throughout your project. See step 9 for ways to even out the light distribution.

Step 5: Bundle Fibers

Subdivide your fibers into groups (just one group is shown in the leftmost picture). For my 0.8 cm LED heads, bundles of about 20 fibers worked well. A few inches beyond the edge of the fabric, gently guide the fibers together and secure them together with a mini rubber band. Try to prevent your fibers from going more than 3 inches past the edge of your fabric.

Step 6: Sew

After your fibers are secured, sew your tulle/optic hybrid however you'd like. I layered mine over several skirts. Once the LEDs are attached to your fabric, it will become too ungainly to put under a sewing machine, so plan to hand sew anything after this step.

Design ahead to accommodate the LEDs, microcontroller, and battery pack. I chose to have my LEDs in a giant waistband that got covered by the dress bodice.

Step 7: Attach LEDs

Now it's time to attach the LEDs! This will likely require some experimentation based on the shape of your bulb.


Electrical tape is your friend.

My first attempt involved several layers of heat shrink tubing, which was not very effective since the bundle of fibers was much smaller than the radius of the LED. If you choose to use heat shrink, test your heat gun on a throwaway bundle of fibers first -- too much heat will melt them.

While super glue will keep your fibers from budging, it significantly dulled the light in my test bundle, and dissolved the rubber band. I wouldn't recommend it.


Ultimately, my most effective method was face-to-face electrical tape.

Start by trimming your fiber bundles just beyond the rubber band. A nice even surface will help the light shine into all fibers equally. Cut two pieces of electrical tape long enough to cover the LED as well as the fibers up to the rubber band. Sandwich your LED and fiber bundle between these two pieces of electrical tape as tightly as possible, and repeat for each LED in your fabric. If your LEDs still have exposed surfaces, use more electrical tape to prevent light from leaking.

Step 8: Add Microcontroller

Solder power, ground, and data lines between your microcontroller and your LEDs. I used a Gemma since it's flat, lightweight, and easy to power.

Now it's time to decide how you'd like your fabric to cycle through colors. If you're adding any sensor-triggered effects, now is the time to solder those components as well. I used Adafruit's rainbow() NeoPixel function, which you can find here. Remember to change the parameters at the top to match your data pin number and number of LEDs.

Step 9: Sand the Fibers

Now for the fun part: coaxing more light out of your fibers wherever you'd like. Nicking the fiber optic casing allows some light to escape. My two most successful tools for this were sandpaper and an open pair of scissors. For sandpaper, you can choose to sand at random intervals, or "strip" the ends 1-2 cm from the tip for a gradual glow. For scissors, open them wide and use a single blade to repeatedly tap the fiber. I recommend doing this in a dark room with the LEDs on so you can see your progress.

Left photo: sanded fiber (top); unsanded fiber (bottom).

Right photo: All fibers sanded about 2cm from the tips.

Step 10: Power Up!

I'm a big fan of the Gemma's JST battery plugin. I directly plugged in a lithium 3.7V 2500mAh battery that sits in the back waistband of the dress. Consider the weight, lifetime, and size of your battery in relation to your project.

Power up your board, turn out the lights, and watch your fabric sparkle!

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    24 Discussions


    Question 4 months ago on Step 1

    This looks amazing! I'm trying to do something similar... Do you know where you got your fiber optic material from? I'm looking online and not seeing anything close to $15! If you could provide a link from where you got yours that would be greatly appreciated! Thanks! :)


    Question 5 months ago

    Im working on a similar project in school right now but I have some questions.
    Could you use a complete set of Led's? So you dont have to buy a battery pack and everything else extra

    And do you think leds like to one on the picture would work aswell?

    and could you sand the filaments before weaving them into the fabric?

    Thank you!

    1 answer

    Answer 5 months ago

    Hello! A complete set of LEDs should work just fine. I think you would need much larger LEDs than the ones in the picture, though. If you want all the fibers to light up, every strand needs to have a light shining directly into it. It seems like you'd only be able to get 1-2 fibers attached to each LED with those, but if you choose wider lights, you might be able to get bundles of 10 or more fibers attached to each light. You can definitely sand the filaments before weaving them in! Seeing the light shining through the filaments might change your decision about where to sand and how much, though, so consider that. Let me know if you have any more questions!


    Question 6 months ago on Step 6

    Oh my goodness, this is AWESOME! I'm a high school costumer and really want to jazz up the Fairy Godmother for our upcoming Cinderella.

    Would it work to sew my garment and then weave the optic strands through afterwards? Was thinking of a white satin layer, covering every panel in tulle, and then weaving (of course keeping in mind connection points etc.

    Also, if we add a powerful enough battery/driver and I sand the fibers will they be visible under stage lighting? I want a subtle effect, doesn't have to be super bright. But I also don't want to go to all this trouble and have it not show up!


    3 answers

    Answer 6 months ago

    This would look so magical for your Fairy Godmother! My biggest concern would be the lighting you mentioned. I found that the fiber optics are really only noticeably bright in almost complete darkness (the last two pictures were in a darker environment than it seems). If there will still be a fair amount of light on stage, I would consider something like this instructable :
    which uses much more powerful lighting. I've made a similar version that is quite bright even in full lighting, feel free to send me any questions you might have about adapting this to your needs.

    If you do go with my fiber optic version, keep in mind that your lights and battery will need to live on the same side of the fabric as the fibers. So if you weave the filament on the outer tulle layer, the lights would need to be covered up by extra panels on the bodice / a large waistband.

    This is a great idea for your costume, please don't hesitate with any future questions! :)


    Reply 6 months ago

    Thanks so much for your prompt reply! Really appreciate it :-)
    I should have added I'm a parent costumer, not a student!
    I looked at the skirt you suggested. My only issue is you can still see the individual bulbs, which I was trying to avoid so the effect was more "magical".
    My husband is in tech and has access to "lots of the things". He has some ultra bright LEDs that he thought might provide enough light to show some glow under stage lights. Do you have any thoughts on this? Or were you already using ultrabrights?

    I can also ask our lighting designer to assist with perhaps dimming that part of the stage while the Fairy Godmother does her thing. My husband suggested he could put some sort of servo switch in her wand to activate the skirt while she's casting her spells. Sounds complicated to me!



    Reply 6 months ago

    I agree that the fiber optics look much more magical than the LED strips! I did not have ultra bright LEDs, so that would be a step in the right direction. Keep in mind that the amount of light you can output is bounded by the diameter of the fiber tube, though. If you have the time to weave the tubes more densely, that would be very helpful, too — mine were anywhere between a quarter inch and an inch apart, which is not as dense as I would’ve liked. If you have the budget, I would recommend buying a spool of fiber optics and holding them up to your LEDs to get a feel for how much light you’ll get.

    I also want to give you plenty of notice that the electrical tape method of attachment wasn’t super effective. The fiber bundles kept popping out when I was transporting the dress. Superglue had a tendency to melt my rubber bands. You might have some success with heat shrink tubing, depending on the shape of your LEDs.

    With some experimentation, I think you’ll have a stunning dress! It may seem daunting but the results are worth it :)


    Question 11 months ago

    This looks so cute. Where did you incorporate the battery pack?

    1 answer

    Reply 11 months ago

    Thank you! :) It's sitting in the back by the zipper, right above the waist. There's a small pocket so it can sit between the dress lining and the skin.


    1 year ago

    Lovely!! What would you imagine was the total cost in time and in materials?

    4 replies

    Reply 1 year ago

    Thank you! And thanks for reminding me, I'll add that to the materials step. My estimate is around 30 hours, with at least 10 of those going towards weaving the fibers into the tulle. The cost was around $80 total: $15 for a 500 foot spool of fiber optics, $14 for a string of ~60 LEDs (I only needed ~18), $10 for the Gemma, $15 for the lithium battery, and $25 for fabric. Your milage will vary a lot depending on the length of your design. The long skirt and fancier fabric added a fair amount to the price tag, but a short skirt or dress could be pretty reasonable.


    Reply 1 year ago

    This is awesome! What was the square footage of the fabric that got fibers woven through it? Thanks you!!


    Reply 1 year ago

    Thank you! :) It was a circle skirt of tulle roughly 44" in radius at the widest part, made from roughly 3 yards of 60" fabric if I recall correctly.


    1 year ago

    lovely! not washable, which could be a problem eventually. parties and outdoor music festivals where trippy light displays after dark are popular are known for occasional spillage, or falling down in the dirt when you're tripping hard. um, over stuff laying on the ground - yeah, that's what I meant :)

    perhaps if the tulle / fiber optic layer could be made removable so the underlying fabric skirt could be laundered, this could have a longer lifespan.

    maybe make the big waistband be just a 'cover/envelope' closed with some small velcro tabs or snaps, so the whole control & power supply part can come out along with the tulle overlay...

    2 replies

    Reply 1 year ago

    It's probably dry-cleanable as is or with just some minor mods.

    Great looking skirt, by the way.


    Reply 1 year ago

    I completely agree, thanks for the suggestion! If the LEDs are small enough and the waistband is large enough, the tulle layer could be snapped/zippered/velcroed on top and then just covered up. That would also help the look convert to daytime wear -- I was a little sad that my sparkly organza was covered up by the plastic cables in full lighting.


    Question 1 year ago

    Where did you source fibre filament?

    1 answer

    1 year ago

    Good call using this style of LED with small bundles of fibers - the effect can actually be seen in a lighted room! The other problem with using flat lensed LEDs to illuminate fibers is that most of the light is wasted because it is radiated beyond the narrow acceptance angle of the fibers.