An accessory device designed to be worn on a leg or arm could greatly benefit from this sort of power generation, and could lengthen the amount of time between charging.

FORBES: Apple Patent For Solar Watch Could Fire Up Stock Again

The tape is designed to increase the spreading of light in the light guide from each LED, which greatly increases the allowable LED spacing.

ENGADGET: 3M Uniformity Tape improves lighting quality on LED edge-lit LCDs, lowers production costs