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How to Put an LED in a Bead

Modern light-emitting diodes (LEDs) are one of the most efficient light sources. They create their light by sending electrons through finely structured material, giving energy to the electrons that then emit very well controlled light. But, as with any microcircuit, the fine features only retain their function if they're protected from environmental contamination, physical damage and chemical degradation. So the LED die must be encapsulated in a protective material. There are two common types of encapsulants: epoxy-based and silicone-based, but both are applied the same way.

Things You'll Need

Bare LED die
Epoxy or silicone resin
Thin latex (surgical) gloves
Syringe

Instructions

- 1
  Create a clean environment for your work. You don't want to open a bare LED die package in your woodshop, or any other environment filled with dust. Ideally, you will have a closed room where you can run a HEPA filter to keep the dust under control.
- 2
  Put the gloves on and place a few CCs of encapsulant in the syringe. Mix an epoxy resin according to the directions, paying attention to the working time. Don't mix it until you're ready to apply it. The silicone resin does not need premixing.
- 3
  Hold the syringe upright and push a few drops of resin out, getting rid of air trapped in the syringe. Have a paper towel ready to catch the excess resin.
- 4
  Inject the resin into the well surrounding the LED die. The LED will be at the bottom of a small recess, holding just a few milliliters of resin.

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