Disclosed herein are an optical device, such as a connector or mode
enlarger, and a method of fabricating the device. The disclosed device
includes an optical medium having a first face for, e.g., permanent
attachment to a waveguide, a second face for, e.g., a non-permanent
connection, and a region between the first and second faces. A non-fiber,
connector waveguide is disposed in the region to propagate the
single-mode signal from the first face to the second face. The connector
waveguide is optically matched to the waveguide at the first face to
receive the single-mode signal carried by the waveguide. The connector
waveguide includes a taper section such that the connector waveguide is
enlarged at the second face to support an expanded beam of the
single-mode signal for propagation through the non-permanent connection.
In some cases, the taper section receives the single-mode signal from an
input section of the connector waveguide to generate an expanded or
narrowed beam of the single-mode signal via discrete modulation of
waveguide cross-section. An output section of the connector waveguide
then supports the propagation of the expanded or narrowed beam of the
single-mode signal through the non-permanent connection.