A waveguide structure is provided. A silicon substrate layer, a silicon waveguide layer, a first silicon dioxide layer, a silicide waveguide layer, and a second silicon dioxide layer are stacked in sequence, the silicon waveguide layer is a conical waveguide layer, the silicon waveguide layer and the silicide waveguide layer are coupled by using an evanescent wave, the silicide waveguide layer includes multiple first waveguide blocks and multiple second waveguide blocks, a material of the first waveguide blocks is the same as a material of the silicide waveguide layer, and a refractive index of a material of the second waveguide blocks is lower than a refractive index of the material of the first waveguide blocks. By using the waveguide structure, a waveguide flare size can be increased, so as to match a mode size of a fiber core of an optical fiber.

Multilevel leaky-mode optical elements, including reflectors, polarizers, and beamsplitters. Some of the elements have a plurality of spatially modulated periodic layers coupled to a substrate. For infrared applications, the optical elements may have a bandwidth larger than 600 nanometers.

Multilevel leaky-mode optical elements, including reflectors, polarizers, and beamsplitters. Some of the elements have a plurality of spatially modulated periodic layers coupled to a substrate. For infrared applications, the optical elements may have a bandwidth larger than 600 nanometers.

Devices and systems to perform optical alignment by using one or more liquid crystal layers to actively steer a light beam from an optical fiber to an optical waveguide integrated on a chip. An on-chip feedback mechanism can steer the beam between the fiber and a grating based waveguide to minimize the insertion loss of the system.

A photoelectric conversion device includes a substrate having a first surface and a second surface that is an opposite side of the first surface, wherein one of the first and second surfaces is a light incidence surface, a photodiode (PD) formed in the first surface of the substrate, a reflective layer formed on one of the first and second surfaces of the substrate, which is the opposite side of the light incidence surface, and a microlens formed on the light incidence surface of the substrate.

In order to prevent non-uniformity in emission wavelength among different sites along an optical axis direction, provided is a resonator portion including: a waveguide which includes a first area and a second area being adjacent to the first area; and diffraction gratings formed along an optical axis direction. The effective refraction index in the first area is larger than the one in the second area, and the thickness in the first area is larger than the one in the second area. A pitch at the adjacent diffraction gratings at a boundary between the first area and the second area is narrower both than pitches of the diffraction gratings that are formed in the first area and than pitches of the diffraction gratings that are formed in the second area.

In order to prevent non-uniformity in emission wavelength among different sites along an optical axis direction, provided is a resonator portion including: a waveguide which includes a first area and a second area being adjacent to the first area; and diffraction gratings formed along an optical axis direction. The effective refraction index in the first area is larger than the one in the second area, and the thickness in the first area is larger than the one in the second area. A pitch at the adjacent diffraction gratings at a boundary between the first area and the second area is narrower both than pitches of the diffraction gratings that are formed in the first area and than pitches of the diffraction gratings that are formed in the second area.

A photonic radiator used for a photonic phased array antenna includes a waveguide including a waveguide clad and a waveguide core that uses semiconductor materials, and a grating that radiates an output light wave to a space by using scattering of an input light wave incident in a direction of the waveguide.

A photonic radiator used for a photonic phased array antenna includes a waveguide including a waveguide clad and a waveguide core that uses semiconductor materials, and a grating that radiates an output light wave to a space by using scattering of an input light wave incident in a direction of the waveguide.

An optical coupling may involve orienting a waveguide and a lens such that light rays are focused on a surface. The lens may involve the use of a material having a variable refractive index to focus rays of light along first axis and a curved surface to focus the rays of light along a second axis.