Patent ID: 7521727

Claim:
A light emitting device comprising: a) a multi-layer stack comprising: an n-doped layer; a light-generating layer; and a p-doped layer, wherein said multi-layer stack has a luminous stack surface; and b) an encapsulant layer comprising: a proximal patterned encapsulant region comprising: a first recess set comprising at least one first recess comprising first recess filler; optionally, a second recess set comprising at least one second recess comprising a second recess filler; and a proximal patterned encapsulant surface disposed upon said luminous stack surface; and wherein at least one of said first recess set and said second recess set has a pattern wherein: said pattern is a periodic pattern, said pattern has a feature size, in at least one lateral dimension, of at least 5 nanometers and no more than 5,000 microns; said periodic pattern has a period, in at least one lateral dimension, of at least 10 nanometers and no more than 5,000 microns; said first recess has a maximum recess depth of at least 25 nanometers and no more than 10,000 microns; and said second recess has a maximum recess depth of at least 25 nanometers and no more than 10,000 microns; wherein at least one of said first recess and said second recess has a recess opening coincident with said proximal patterned encapsulant surface; and optionally, an unpatterned encapsulant region comprising an encapsulant material; wherein said first recess filler differs in refractive index from at least one of second recess filler and said encapsulant material by at least 0.001 and no more than 3.0; and wherein at least one of said first recess filler, said second recess filler, and said encapsulant material has a mean density of at least 0.03 g/cm 3 and no more than 0.60 g/cm 3 .