An optical interconnect for optically coupling at least a first optical integrated circuit and a second optical integrated circuit. The optical interconnect comprises at least two layers of optically transparent material. There is a first optical waveguide arranged along a surface of a first one of the at least two layers of optically transparent material. There is further a first non-guided optical path extending from the first optical waveguide through the at least two layers of optically transparent material. A first reflective element is arranged to receive light from at least one of the first non-guided optical path and the first optical waveguide and direct the light to the other of the first non-guided optical path and the first optical waveguide. At least one lens is arranged at a boundary between two of the at least two layers of optically transparent material. The at least one lens is arranged to receive and focus light travelling along the first non-guided optical path.

To provide a multiplexer that makes it possible to achieve a reduction in size and that minimizes the influence of the expansion of laser light on a multiplexing unit. A multiplexer is provided with a plurality of waveguides, multiplexing units that are provided at an intermediate location within the waveguides, and laser light sources, wherein: the first multiplexing unit is arranged at a position that is closest to the laser light sources; and the laser light sources that have an optical axis at a position that is separated from the transmission axis of the visible light that is introduced into the first multiplexing unit are arranged so that the optical axis is inclined with respect to the transmission axis and the outer periphery of laser light that expands at a predetermined expansion angle passes in front of the first multiplexing unit.

To provide a multiplexer that makes it possible to achieve a reduction in size and that minimizes the influence of the expansion of laser light on a multiplexing unit. A multiplexer is provided with a plurality of waveguides, multiplexing units that are provided at an intermediate location within the waveguides, and laser light sources, wherein: the first multiplexing unit is arranged at a position that is closest to the laser light sources; and the laser light sources that have an optical axis at a position that is separated from the transmission axis of the visible light that is introduced into the first multiplexing unit are arranged so that the optical axis is inclined with respect to the transmission axis and the outer periphery of laser light that expands at a predetermined expansion angle passes in front of the first multiplexing unit.

An integrated circuit (IC) device includes an optical IC substrate, a local trench inside the optical IC substrate, and a photoelectronic element including a photoelectric conversion layer buried inside the local trench. The photoelectric conversion layer is buried inside the local trench in the optical IC substrate to form the photoelectronic element. Thus, the IC device may inhibit warpage of the optical IC substrate.

An integrated circuit (IC) device includes an optical IC substrate, a local trench inside the optical IC substrate, and a photoelectronic element including a photoelectric conversion layer buried inside the local trench. The photoelectric conversion layer is buried inside the local trench in the optical IC substrate to form the photoelectronic element. Thus, the IC device may inhibit warpage of the optical IC substrate.

A photonic integrated circuit chip includes a substrate and a wafer on the substrate. The wafer itself includes a photonic grating coupler with a taper portion and grating features. The grating features extend from the taper portion toward the substrate.

A photonic integrated circuit chip includes a substrate and a wafer on the substrate. The wafer itself includes a photonic grating coupler with a taper portion and grating features. The grating features extend from the taper portion toward the substrate.

An example device includes a nanovoided polymer element, a first electrode, and a second electrode. The nanovoided polymer element may be located at least in part between the first electrode and the second electrode. In some examples, the nanovoided polymer element may include anisotropic voids. In some examples, anisotropic voids may be elongated along one or more directions. In some examples, the anisotropic voids are configured so that a polymer wall thickness between neighboring voids is generally uniform. Example devices may include a spatially addressable electroactive device, such as an actuator or a sensor, and/or may include an optical element. A nanovoided polymer layer may include one or more polymer components, such as an electroactive polymer.

An optical density measuring apparatus for measuring density of a gas or a liquid to be measured includes a light source capable of irradiating light into a core layer, a detector capable of receiving light propagated through the core layer, and an optical waveguide that includes a substrate and the core layer. The core layer includes a light propagation unit and a first diffraction grating unit that receives light from the light source and guides the light to the light propagation unit, which includes a propagation channel capable of propagating light in an extending direction of the light propagation unit. The first diffraction grating unit is disposed near to and facing a light-emitting surface of the light source. The first diffraction grating unit includes first diffraction gratings, at least two of which receive light emitted from the same light-emitting surface of the light source.

Disclosed are apparatuses for optical coupling and a system for communication. In one embodiment, an apparatus for optical coupling including a substrate and a grating coupler is disclosed. The grating coupler is disposed on the substrate and includes a plurality of coupling gratings arranged along a first direction, wherein effective refractive indices of the plurality of coupling gratings gradually decrease along the first direction.