Patent ID: 9684129
Date: 2017-06-20
CPC Classifications: G02B

Claim:
1. A waveguide device, comprising: a termination structure comprised of a light blocking material, the light blocking material bounding a passageway extending longitudinally thereinto to an end face; a waveguide having a terminal end comprising a taper portion with a waveguide width decreasing toward a terminal point, the taper portion having a taper angle that is substantially equal to or smaller than a critical angle at which adiabatic transition occurs, the terminal end of the waveguide being positioned within the passageway, a gap being formed by the passageway longitudinally between the terminal point of the waveguide and the end face of the passageway; wherein light from the waveguide enters the light blocking material through the end face of the passageway at an oblique incidence angle, and wherein a width of the passageway is constant at least in a region corresponding to the taper portion of the waveguide.