| CPC G02B 6/14 (2013.01) [G02B 6/1228 (2013.01); G02B 2006/12061 (2013.01)] | 23 Claims |

|
1. An apparatus, comprising:
a first optical waveguide; and
a second optical waveguide disposed partially within the first optical waveguide comprising:
a first portion having a first cross-section, in a first plan view, having a first about trapezoidal configuration and a second cross-section, substantially orthogonal to the first cross-section in a second plan view, having a second about trapezoidal configuration,
wherein the apparatus is configured to expand an optical signal propagating from the second optical waveguide to the first optical waveguide.
|