OPTICAL WAVEGUIDE WITH ENSCAPSULATED LIQUID UPPER CLADDING

摘要

An optical device includes a planar substrate (10) on top of which is deposited a layer of waveguide material (13). A waveguide circuit (11, 12) is etched into the waveguide material (13). A cover (40) selectively encapsulates the substrate (10) around the waveguide circuit while leaving space to provide a gap above the waveguide circuit (404). A liquid material (30) having a lower index of refraction than the waveguide material is filled into the gap above the waveguide circuit such that the liquid acts as the upper cladding for the waveguide circuit. The cover may be in the form of a substrate on which are formed optical modifying elements (22) for modifying light signals propagating in the waveguide circuit.