Abstract: An optical coupler for use in optical communication includes a buried layer, a support layer, a waveguide layer, and an upper cladding layer. In a height direction, the support layer is located between the buried layer and the waveguide layer, and the waveguide layer is located between the support layer and the upper cladding layer. In a width direction, the waveguide layer and the support layer are located inside the upper cladding layer. A material of the waveguide layer is different from a material of the support layer. The support layer is located inside the upper cladding layer such that two sides of the support layer include the upper cladding layer.

Abstract: A multi-wavelength laser is provided, including a reference wavelength-tunable laser, N?1 secondary wavelength-tunable lasers, N beam splitters, a phase modulator, and N?1 frequency difference detection apparatuses. The reference wavelength-tunable laser is connected to one beam splitter which includes two output ports, and one of the output ports is connected to the phase modulator. The phase modulator is separately connected to the N?1 frequency difference detection apparatuses. The N?1 secondary wavelength-tunable lasers one-to-one correspond to remaining N?1 beam splitters and the N?1 frequency difference detection apparatuses. The secondary wavelength-tunable laser is connected to a corresponding beam splitter, the corresponding beam splitter includes two output ports, and one of the output ports is connected to a corresponding frequency difference detection apparatus. N is a positive integer not less than 2.

Abstract: An optical signal sending apparatus includes an optical modulator, a differential driver, and a phase modulator. The optical modulator includes an optical input end, a first modulation region, a connection region, a second modulation region, and an optical output end. The first modulation region includes a first modulation arm and a second modulation arm. The second modulation region includes a third modulation arm and a fourth modulation arm. Each modulation arm includes an optical waveguide and electrodes on two sides of the optical waveguide. A differential drive signal is used to drive the two modulation regions, so that photoelectric signal modulation is implemented. The modulation arms are arranged in a stacked manner, so that a size of the optical modulator can be greatly reduced, thereby facilitating miniaturization.

Abstract: An optical frequency comb light source and an optical frequency comb generation method, where the light source includes a laser diode, a coupler, a Kerr nonlinear device, a beam splitter, and a phase shifter. The laser diode is connected to one input port of the coupler, and the other input port of the coupler is connected to an output port of the phase shifter. An output port of the coupler is connected to an input port of the Kerr nonlinear device. An output port of the Kerr nonlinear device is connected to an input port of the beam splitter. One output port of the beam splitter is connected to an input port of the phase shifter. The other output port of the beam splitter is configured to output a plurality of optical frequency combs. A multi-wavelength light source with relatively high power may be provided.

Abstract: An optical modulator includes a waveguide layer, an electro-optical material layer, and electrodes. The waveguide layer includes a sub-wavelength waveguide; the electro-optical material layer is disposed on a surface of the sub-wavelength waveguide, and the sub-wavelength waveguide is configured to diffuse a light field at the waveguide layer into the electro-optical material layer; the electrodes are disposed on a surface of the electro-optical material layer, and a connection line between the electrodes is parallel to a plane on which the electro-optical material layer is located, or the electrodes are disposed on two sides of the electro-optical material layer, and a connection line between the electrodes intersects with a plane on which the electro-optical material layer is located; and the electrodes are configured to apply an electrical signal to the electro-optical material layer.

Abstract: An optical frequency comb light source and an optical frequency comb generation method, where the light source includes a laser diode, a coupler, a Kerr nonlinear device, a beam splitter, and a phase shifter. The laser diode is connected to one input port of the coupler, and the other input port of the coupler is connected to an output port of the phase shifter. An output port of the coupler is connected to an input port of the Kerr nonlinear device. An output port of the Kerr nonlinear device is connected to an input port of the beam splitter. One output port of the beam splitter is connected to an input port of the phase shifter. The other output port of the beam splitter is configured to output a plurality of optical frequency combs. A multi-wavelength light source with relatively high power may be provided.

Abstract: A multi-wavelength laser includes a reference wavelength-tunable laser, N?1 secondary wavelength-tunable lasers, N beam splitters, a phase modulator, and N?1 frequency difference detection apparatuses. The reference wavelength-tunable laser is connected to one beam splitter, the beam splitter includes two output ports, and one of the output ports is connected to the phase modulator. The phase modulator is separately connected to the N?1 frequency difference detection apparatuses. The N?1 secondary wavelength-tunable lasers one-to-one correspond to remaining N?1 beam splitters and the N?1 frequency difference detection apparatuses. The secondary wavelength-tunable laser is connected to a corresponding beam splitter, the corresponding beam splitter includes two output ports, and one of the output ports is connected to a corresponding frequency difference detection apparatus. N is a positive integer not less than 2.