A mode converter provided in the present invention includes an input multimode waveguide, an output multimode waveguide, and a first conversion waveguide, where the input multimode waveguide is configured to receive a first signal which mode is a first mode; the first conversion waveguide has an input coupling waveguide with a first effective refractive index, and has an output coupling waveguide with a second effective refractive index; the first conversion waveguide is configured to perform, by using the input coupling waveguide, evanescent wave coupling on the first signal that is in the first mode and that is transmitted in the input multimode waveguide, and couple the first signal to the second mode of the output multimode waveguide by using the output coupling waveguide, so as to obtain the first signal in the second mode; and the output multimode waveguide is configured to output the first signal in the second mode.

According to one example, the present application discloses an optical circuit comprising a grating to receive input light of mixed polarizations and output light of a same polarization to a first waveguide and a second waveguide. The first waveguide and second waveguide are optically coupled to a plurality of resonators that are coupled to a plurality of gratings that are to output light of mixed polarizations.

According to one example, the present application discloses an optical circuit comprising a grating to receive input light of mixed polarizations and output light of a same polarization to a first waveguide and a second waveguide. The first waveguide and second waveguide are optically coupled to a plurality of resonators that are coupled to a plurality of gratings that are to output light of mixed polarizations.

An integrated optical beam steering system includes a photonic crystal nanostructure having a plurality of nanoelements, an input surface to receive light from an imager, and a concave output surface which maintains a desired field of view with suitable coupling efficiency. Parameters of the nanoelements are configured to give rise to a photonic bandgap for a predetermined range of wavelengths. Waveguides are disposed in the nanostructure which comprise negative space formed by the absence of nanoelements and are employed to generate a propagating band within the photonic bandgap. The respective waveguides have inputs disposed on the input surfaces of the nanostructure where light propagates in a respective waveguide in total internal reflection. The respective waveguides further have outputs that have paths with curved portions located in the nanostructure and the outputs are configured normal to the concave output surface.

An integrated optical beam steering system includes a photonic crystal nanostructure having a plurality of nanoelements, an input surface to receive light from an imager, and a concave output surface which maintains a desired field of view with suitable coupling efficiency. Parameters of the nanoelements are configured to give rise to a photonic bandgap for a predetermined range of wavelengths. Waveguides are disposed in the nanostructure which comprise negative space formed by the absence of nanoelements and are employed to generate a propagating band within the photonic bandgap. The respective waveguides have inputs disposed on the input surfaces of the nanostructure where light propagates in a respective waveguide in total internal reflection. The respective waveguides further have outputs that have paths with curved portions located in the nanostructure and the outputs are configured normal to the concave output surface.

In a light deflection device and a lider device, a parallel operation can be realized with a simple constitution, so as to avoid enlargement or complication of a system. The reflection angle of the light deflection device depends on a wavelength and a refractive index, so that light beams with respective wavelengths different from each other are simultaneously and parallelly deflected in directions of deflection angles each defined by the wavelength and the refractive index. The light beams with the plural wavelengths different from each other are deflected at the different deflection angles each defined by each wavelength and the refractive index, so that they can be deflected simultaneously and parallelly. The plural deflected light beams can be distinguished from each other based on the difference in the wavelength and the deflection angle of the light, even in the simultaneous and parallel operation.

In a light deflection device and a lider device, a parallel operation can be realized with a simple constitution, so as to avoid enlargement or complication of a system. The reflection angle of the light deflection device depends on a wavelength and a refractive index, so that light beams with respective wavelengths different from each other are simultaneously and parallelly deflected in directions of deflection angles each defined by the wavelength and the refractive index. The light beams with the plural wavelengths different from each other are deflected at the different deflection angles each defined by each wavelength and the refractive index, so that they can be deflected simultaneously and parallelly. The plural deflected light beams can be distinguished from each other based on the difference in the wavelength and the deflection angle of the light, even in the simultaneous and parallel operation.

Methods and systems for optoelectronics transceivers integrated on a CMOS chip are disclosed and may include receiving optical signals from optical fibers via grating couplers on a top surface of a CMOS chip, which may include a guard ring. Photodetectors may be integrated in the CMOS chip. A CW optical signal may be received from a laser source via optical couplers, and may be modulated using optical modulators, which may be Mach-Zehnder and/or ring modulators. Circuitry in the CMOS chip may drive the optical modulators. The modulated optical signal may be communicated out of the top surface of the CMOS chip into optical fibers via grating couplers. The received optical signals may be communicated between devices via waveguides. The photodetectors may include germanium waveguide photodiodes, avalanche photodiodes, and/or heterojunction diodes. The CW optical signal may be generated using an edge-emitting and/or a vertical-cavity surface emitting semiconductor laser.

Methods and systems for optoelectronics transceivers integrated on a CMOS chip are disclosed and may include receiving optical signals from optical fibers via grating couplers on a top surface of a CMOS chip, which may include a guard ring. Photodetectors may be integrated in the CMOS chip. A CW optical signal may be received from a laser source via optical couplers, and may be modulated using optical modulators, which may be Mach-Zehnder and/or ring modulators. Circuitry in the CMOS chip may drive the optical modulators. The modulated optical signal may be communicated out of the top surface of the CMOS chip into optical fibers via grating couplers. The received optical signals may be communicated between devices via waveguides. The photodetectors may include germanium waveguide photodiodes, avalanche photodiodes, and/or heterojunction diodes. The CW optical signal may be generated using an edge-emitting and/or a vertical-cavity surface emitting semiconductor laser.

Methods and systems for partial integration of wavelength division multiplexing and bi-directional solutions are disclosed and may include, an optical transceiver on a silicon photonics integrated circuit coupled to a planar lightwave circuit (PLC). The silicon photonics integrated circuit may include a first modulator and first light source that operates at a first wavelength and a second modulator and second light source that operates at a second wavelength. The transceiver and PLC are operable to modulate a first continuous wave (CW) optical signal from the first light source utilizing the first modulator and modulate a second CW optical signal from the second light source utilizing the second modulator. The modulated signals may be communicated from the modulators to the PLC utilizing a first pair of grating couplers in the IC and combined in the PLC.