In an epitaxial structure of a solid state lighting system, electrical
current injection into the active layer is used to excite the photon
emission. The present invention employs a unique waveguide layer in the
epitaxial structure for trapping the light generated by the active layer
in the fundamental waveguide mode. Multiple photonic crystal regions
located either outside or inside one or more current injection regions
extract photons from the waveguide layer(s). This novel design optimizes
the interplay of electrical pumping, radiation and optical extraction to
increase the optical output to several times that of conventional LEDs. A
transparent and conductive ITO layer is added to the surface of an
epitaxial structure to reduce the interface reflection in addition to
functioning as a current spreading layer. The present invention creates
solid state lighting with high optical output and high power efficiency.