An optofluidic photoreactor including an optical waveguide having an input, characterized by an evanescent optical field confined along an outer surface of the optical waveguide produced by radiation propagating in the optical waveguide, means for inputting light to the input of the optical waveguide, and a photoactive material disposed substantially only within the evanescent field. A method for optically activating a photoactive material in an optofluidic photoreactor to convert carbon dioxide and water into other molecules that may be useful as a fuel or a chemical feedstock.

A method for producing a semiconductor optical device includes the steps of bonding a semiconductor chip to an SOI substrate having a waveguide, the semiconductor chip having an optical gain and including a first cladding layer, a core layer, and a second cladding layer that contain III-V group compound semiconductors and are sequentially stacked in this order, forming a covered portion with a first insulating layer on the second cladding layer, etching partway in the thickness direction the second cladding layer exposed from the first insulating film, forming a second insulating film covering from the covered portion to a part of a remaining portion of the second cladding layer, and forming a first tapered portion that is disposed on the waveguide and tapered along the extending direction of the waveguide by etching the core layer and the second cladding layer exposed from the second insulating film.

Example embodiments relate to imaging systems and methods for acquisition of multi-spectral images. One example imaging system includes a detector that includes an array of light sensitive elements arranged in rows and columns. Each light sensitive element is configured to generate a signal dependent on an intensity of light incident onto the light sensitive element. The imaging system also includes a plurality of wavelength separating units. Each wavelength separating unit is configured to spatially separate incident light within a wavelength range into a number of wavelength bands distributed along a line. The line is a straight line. Each wavelength band along the line is associated with a mutually unique light sensitive element. Further, the imaging system includes a processing unit configured to define a number of mutually unique clusters of light sensitive elements for summing signals from the light sensitive elements within the respective clusters.

An optical phase shifter may include a waveguide core that has a top surface, and a semiconductor contact that is laterally displaced relative to the waveguide core and is electrically connected to the waveguide core. A top surface of the semiconductor contact is above the top surface of the waveguide core. The waveguide core may include a p-type core region and an n-type core region. A p-type semiconductor region may be in physical contact with the n-type core region of the waveguide core, and an n-type semiconductor region may be in physical contact with the p-type core region of the waveguide core. A phase shifter region and a light-emitting region may be disposed at different depth levels, and the light-emitting region may emit light from a phase shifter region that is in a position adjacent to the light-emitting region.

An all fiber wavelength selective coupler provides wavelength selective transfer of optical energy between two or more separated waveguides. The coupler includes signal cores that are separated enough that they can be fusion spliced to standard fibers as lead-in and lead-out pigtails. A bridge between the signal cores facilitates transfer of the optical energy through a process of evanescent coupling. In one example, the bridge is formed of a series of graded index cores.

The present disclosure relates to semiconductor structures and, more particularly, to waveguide attenuators and methods of manufacture. The structure includes: a main bus waveguide structure; a first hybrid waveguide structure evanescently coupled to the main bus waveguide structure and comprising a first geometry of material; and a second hybrid waveguide structure evanescently coupled to the main bus waveguide structure and comprising a second geometry of the material.

A wavelength demultiplexing device configured so as to spatially distributing the spectral contributions of an incident light beam, when in use, and which includes a linear waveguide and a planar waveguide, formed in a coplanar way and adapted to be optically coupled with one another along a coupling line, by evanescent coupling. Such a device may further include diffraction gratings located in the planar waveguide, to extract light out of the latter.

A compact collimator or projector includes a waveguide having a slab core structure supporting at least two lateral modes of propagation. A light beam coupled into a first mode propagates to an edge of the waveguide where it is reflected by a reflector to propagate back. Upon propagation back and forth, the light is converted into a second mode. An out-coupling region, such as an evanescent coupler, is provided to out-couple the light propagating in the second mode. The reflector may have focusing power to collimate the out-coupled light beam. The light beam may be converted from the first to the second mode without being reflected from a reflector.

Optical apparatus and methods of manufacture thereof An optical apparatus (20) for evanescently coupling an optical signal across an (interface (30) is described. The optical apparatus (20) comprises a first substrate (22) and a second substrate (24). The optical signal is evanescently coupled between a first waveguide (26) formed by laser inscription of the first substrate (22) and a second waveguide (28) of the second substrate (22). The first waveguide (26) comprises a curved section (34) configured to provide evanescent coupling of the optical signal between the first and second waveguides (26, 28) via the interface (30).

The present disclosure relates to semiconductor structures and, more particularly, to waveguide attenuators and methods of manufacture. The structure includes: a main bus waveguide structure; a first hybrid waveguide structure evanescently coupled to the main bus waveguide structure and comprising a first geometry of material; and a second hybrid waveguide structure evanescently coupled to the main bus waveguide structure and comprising a second geometry of the material.