Free-space coupler devices are disclosed. In one embodiment, a free-space coupler device comprises a waveguide structure including a waveguide grating, and an out-of-plane coupler separated from and in optical communication with the waveguide grating. The waveguide grating and the out-of-plane coupler are separated by a distance that will yield an optical resonance at a desired operating frequency or wavelength of an optical signal, thereby maximizing a diffraction power of the optical signal at the out-of-plane coupler while minimizing a reflection power of the optical signal at the out-of-plane coupler.

Processes and apparatuses described herein reduce the manufacturing time, the cost of parts, and the cost of assembly per laser for photonic interconnects incorporated into computing systems. An output side of a laser assembly is placed against an input side of a silicon interposer (SiP) such that each pad in a plurality of pads positioned on the output side of the laser assembly is in contact with a respective solder bump that is also in contact with a corresponding pad positioned on the input side of the SiP. The laser assembly is configured to emit laser light from the output side into an input grating of the SiP. The solder bumps are heated to a liquid phase. Capillary forces of the solder bumps realign the laser assembly and the SiP while the solder bumps are in the liquid phase. The solder bumps are then allowed to cool.

Processes and apparatuses described herein reduce the manufacturing time, the cost of parts, and the cost of assembly per laser for photonic interconnects incorporated into computing systems. An output side of a laser assembly is placed against an input side of a silicon interposer (SiP) such that each pad in a plurality of pads positioned on the output side of the laser assembly is in contact with a respective solder bump that is also in contact with a corresponding pad positioned on the input side of the SiP. The laser assembly is configured to emit laser light from the output side into an input grating of the SiP. The solder bumps are heated to a liquid phase. Capillary forces of the solder bumps realign the laser assembly and the SiP while the solder bumps are in the liquid phase. The solder bumps are then allowed to cool.

Optical alignment of an optical connector to input/output couplers of a photonic integrated circuit can be achieved by first actively aligning the optical connector successively to two loopback alignment features formed in the photonic chip of the PIC, optically unconnected to the PIC, and then moving the optical connector, based on precise knowledge of the positions of the loopback alignment features relative to the input/output couplers of the PIC, to a position aligned with the input/output couplers of the PIC and locking it in place.

A method for on-wafer testing of optical structures of photonic chips that include edge couplers as input/out ports includes defining, in test a test area of the wafer, an edge coupler pair formed of two edge couplers separated by a test gap, which may have a width that is close to the width of a chip-fiber gap during normal operation of the photonic chips. Test areas may include chains of different numbers of the edge coupler pairs for determining coupling loss per edge coupler.

A method for on-wafer testing of optical structures of photonic chips that include edge couplers as input/out ports includes defining, in test a test area of the wafer, an edge coupler pair formed of two edge couplers separated by a test gap, which may have a width that is close to the width of a chip-fiber gap during normal operation of the photonic chips. Test areas may include chains of different numbers of the edge coupler pairs for determining coupling loss per edge coupler.

Free-space coupler devices are disclosed. In one embodiment, a free-space coupler device comprises a waveguide structure including a waveguide grating, and an out-of-plane coupler separated from and in optical communication with the waveguide grating. The waveguide grating and the out-of-plane coupler are separated by a distance that will yield an optical resonance at a desired operating frequency or wavelength of an optical signal, thereby maximizing a diffraction power of the optical signal at the out-of-plane coupler while minimizing a reflection power of the optical signal at the out-of-plane coupler.

Free-space coupler devices are disclosed. In one embodiment, a free-space coupler device comprises a waveguide structure including a waveguide grating, and an out-of-plane coupler separated from and in optical communication with the waveguide grating. The waveguide grating and the out-of-plane coupler are separated by a distance that will yield an optical resonance at a desired operating frequency or wavelength of an optical signal, thereby maximizing a diffraction power of the optical signal at the out-of-plane coupler while minimizing a reflection power of the optical signal at the out-of-plane coupler.

An optical apparatus including a substrate and a refractive element formed above the substrate. The refractive element including a surface with a predetermined radius of curvature, and a group of periodic structures formed on the surface configured to refract or to filter one or more wavelengths of an incident light.

An optical apparatus including a substrate and a refractive element formed above the substrate. The refractive element including a surface with a predetermined radius of curvature, and a group of periodic structures formed on the surface configured to refract or to filter one or more wavelengths of an incident light.