Patent ID: 6363188
Filing Date: 2002-03-26
Classification: G02B,H01S

Abstract:
An apparatus, comprising:a first layer having a refractive index; a second layer having a first portion and a second portion, said second layer having a refractive index greater than the refractive index of said first layer; a third layer having a refractive index greater than the refractive index of said second layer, said third layer having a co-directional grating, the first portion of said second layer being disposed between said first layer and said third layer; a fourth layer having a first portion and a second portion, said fourth layer having the refractive index of said second layer, said third layer being disposed between the first portion of said second layer and the first portion of said fourth layer; and a fifth layer having the refractive index of said first layer, the first portion of said fourth layer being disposed between said third layer and said fifth layer, the second portion of said fourth layer being disposed between said fifth layer and the second portion of said second layer.