A waveguide illuminator includes an input waveguide, a waveguide splitter coupled to the input waveguide, and a waveguide array coupled to the waveguide splitter. The waveguide array includes an array of out-couplers out-coupling portions of the split light beam to form an array of out-coupled beam portions for illuminating a display panel. To reduce optical interference, the waveguide illuminator may have two interlaced waveguide arrays energized by two different light sources. Output polarizations of neighboring light pixels of a display illuminated with such waveguide illuminator may be orthogonal to each other. The frames to be displayed may be broken down into sequentially displayed sub-frames with interleaved pixels.

An integrated mode converter and multiplexer (/demultiplexer) combines a multimode interference coupler, at least one phase-shifter and a symmetrical Y-junction. The dispersion of the multimode interference coupler is engineered through subwavelength structures in order to achieve a very wide bandwidth. Several phase-shifter topologies for further bandwidth enhancement are disclosed, as well as architectures for multiplexing a greater number of optical modes.

An integrated mode converter and multiplexer (/demultiplexer) combines a multimode interference coupler, at least one phase-shifter and a symmetrical Y-junction. The dispersion of the multimode interference coupler is engineered through subwavelength structures in order to achieve a very wide bandwidth. Several phase-shifter topologies for further bandwidth enhancement are disclosed, as well as architectures for multiplexing a greater number of optical modes.

A manufacturing system performs a deposition of an etch-compatible film over a substrate. The etch-compatible film includes a first surface and a second surface opposite to the first surface. The manufacturing system performs a partial removal of the etch-compatible film to create a surface profile on the first surface with a plurality of depths relative to the substrate. The manufacturing system performs a deposition of a second material over the profile created in the etch-compatible film. The manufacturing system performs a planarization of the second material to obtain a plurality of etch heights of the second material in accordance with the plurality of depths in the profile created in the etch-compatible film. The manufacturing system performs a lithographic patterning of a photoresist deposited over the planarized second material to obtain the plurality of etch heights and one or more duty cycles in the second material.

A manufacturing system performs a deposition of an etch-compatible film over a substrate. The etch-compatible film includes a first surface and a second surface opposite to the first surface. The manufacturing system performs a partial removal of the etch-compatible film to create a surface profile on the first surface with a plurality of depths relative to the substrate. The manufacturing system performs a deposition of a second material over the profile created in the etch-compatible film. The manufacturing system performs a planarization of the second material to obtain a plurality of etch heights of the second material in accordance with the plurality of depths in the profile created in the etch-compatible film. The manufacturing system performs a lithographic patterning of a photoresist deposited over the planarized second material to obtain the plurality of etch heights and one or more duty cycles in the second material.

In an example embodiment, a system includes a first grating-coupled laser (GCL) that includes a first laser cavity optically coupled to a first transmit grating coupler configured to redirect horizontally-propagating first light, received from the first laser cavity, vertically downward and out of the first GCL. The system also includes a second GCL that includes a second laser cavity optically coupled to a second transmit grating coupler configured to transmit second light vertically downward and out of the second GCL. The system also includes a photonic integrated circuit (PIC) that includes a first receive grating coupler optically coupled to a first waveguide and configured to receive the first light and couple the first light into the first waveguide. The PIC also includes a second receive grating coupler optically coupled to a second waveguide and configured to receive the second light and couple the second light into the second waveguide.

In an example embodiment, a system includes a first grating-coupled laser (GCL) that includes a first laser cavity optically coupled to a first transmit grating coupler configured to redirect horizontally-propagating first light, received from the first laser cavity, vertically downward and out of the first GCL. The system also includes a second GCL that includes a second laser cavity optically coupled to a second transmit grating coupler configured to transmit second light vertically downward and out of the second GCL. The system also includes a photonic integrated circuit (PIC) that includes a first receive grating coupler optically coupled to a first waveguide and configured to receive the first light and couple the first light into the first waveguide. The PIC also includes a second receive grating coupler optically coupled to a second waveguide and configured to receive the second light and couple the second light into the second waveguide.

A semiconductor structure including a semiconductor substrate, a first patterned dielectric layer, a grating coupler and a waveguide is provided. The semiconductor substrate includes an optical reflective layer. The first patterned dielectric layer is disposed on the semiconductor substrate and covers a portion of the optical reflective layer. The grating coupler and the waveguide are disposed on the first patterned dielectric layer, wherein the grating coupler and the waveguide are located over the optical reflective layer.

A semiconductor structure including a semiconductor substrate, a first patterned dielectric layer, a grating coupler and a waveguide is provided. The semiconductor substrate includes an optical reflective layer. The first patterned dielectric layer is disposed on the semiconductor substrate and covers a portion of the optical reflective layer. The grating coupler and the waveguide are disposed on the first patterned dielectric layer, wherein the grating coupler and the waveguide are located over the optical reflective layer.

Structures including a grating coupler and methods of forming a structure that includes a grating coupler. The grating coupler includes segments that are spaced along a longitudinal axis. Each segment is inclined relative to the longitudinal axis. Each segment includes a first curved section having a first curvature and a second curved section having a second curvature that is inverted relative to the first curvature.