Light-emitting diode light extraction layer having graded index of refraction

Abstract

A light-emitting diode display including a substrate having a driving circuitry and a plurality of light emitting diode structures disposed on the substrate. Each light-emitting diode structure has a light emitting diode with a light emission zone having a planar portion, and a pigmentless light extraction layer of a UV-cured ink disposed over the light-emitting diode. The light extraction layer has a gradient in index of refraction along an axis normal to the planar portion, and the index of refraction of the light extraction layer decreases with distance from the planar portion.

Dependencies are inferred from the claim text.