Each of the frames is lit with a string of LEDs. Both the frame and the LEDs are available from IKEA. Installing the LEDs is very easy with a drill. The photos here capture the process:
- Tape template to back of frame
- Drill holes with 5/32″ bit in all of the circles
- Insert LEDs
- Put back back onto frame
The whole process is expanded a little bit in my Evenly backlit IKEA frame with LEDs Instructable. It only takes about 5-10 minutes for each frame.