Patent ID: 11921298
Assignee: II-VI DELAWARE, INC.
Field: Optics (Instruments)
Classification: CPC G  H | IPC G  H

Claim 20:
21. An optical system, comprising:
an active optical element that includes an active layer configured to convert electrical current to light or to convert light to electrical current and a spot-size converter, the spot-size converter comprising:
a first waveguide structure that extends longitudinally along a waveguide axis from a first end to a second end, the first waveguide structure configured to support a first optical mode at the first end; and
a second waveguide structure formed within the first waveguide structure, wherein:
the second waveguide structure extends longitudinally between the first end and the second end;
the second waveguide structure is configured to support a second optical mode at the second end;
the second optical mode has a different diameter than the first optical mode;
the second waveguide structure includes a waveguide core that has a first cross-sectional area in a first plane normal to the waveguide axis at the first end and a second cross-sectional area in a second plane normal to the waveguide axis at the second end; and
the second cross-sectional area is larger than the first cross-sectional area,, the waveguide core clad by a multi-surfaced clad structure and optically coupled at the second end to the active layer of the active optical element, wherein at least one surface of the multi-surfaced clad structure is clad by air
the multi-surfaced clad structure is spaced apart from a substrate by an index step material layer;
the multi-surfaced clad structure includes indium phosphide with a first refractive index; and
the index step material layer includes doped indium phosphide with a second refractive index that is less than the first refractive index.