Patent ID: 8761346

Claim:
A multilayer optic device having an input face and an output face, the optic device comprising: a high-index material layer having a first real refractive index 1−δ 1 and a first absorption coefficient β 1 ; a low-index material layer having a second real refractive index 1−δ 2 and a second absorption coefficient β 2 ; and a grading zone disposed between the high-index material layer and the low-index material layer, the grading zone comprising a grading layer having a third real refractive index 1−δ 3 and a third absorption coefficient β 3 , such that 1−δ 1 >1−δ 3 >1−δ 2 , wherein at least a portion of one or more of the high-index material layer, the grading zone and the low-index layer comprise one or more corrugations along a first direction, and wherein at least a portion of one or more of the high-index material layer, the grading zone and the low-index layer comprises one or more non-corrugation portions along a first direction.