Patent ID: 7397987
Filing Date: 2008-07-08
Classification: G02B

Abstract:
1. A grating coupler comprising: a first waveguide having an axis, wherein the first waveguide guides light in a direction parallel to the axis of the waveguide; and a first grating associated with the waveguide, the first grating comprising a first plurality of grates and a second plurality of grates separated by a first distance from the first plurality of grates, said first distance being controllable in accordance with a profile of light to be input into the waveguide or extracted from the waveguide, wherein the first plurality of grates, the second plurality of grates and the first distance are selected so that at least one between the first plurality of grates and the second plurality of grates acts both as a reflective element and a coupler, wherein the reflective element is such that light parallel to the axis of the waveguide is reflected in a direction parallel to the axis, and wherein the grates are curved grates.