An optical connector system includes: an optical path-changing device including a fiber-holding part that holds a single-mode optical fiber along a first direction, and a reflection surface that reflects an optical signal; and a relay device on a substrate. The substrate includes a grating coupler for inputting/outputting an optical signal in a second direction that is inclined with respect to a direction perpendicular to a surface of the substrate. The optical path-changing device and the relay device each have an input/output surface to/from which the optical signal is inputted/outputted. A first convex lens is disposed on the input/output surface of the optical path-changing device. A second convex lens is disposed on the input/output surface of the relay device.

Embodiments of the disclosure are generally directed to systems and methods for switchable electroactive devices for head-mounted displays (HMDs). In particular, a method may include (1) applying an electric field to an electroactive element of an electroactive device via electrodes of the electroactive device that are electrically coupled to the electroactive element to compress the electroactive element, which comprises a polymer material defining nanovoids, such that an average size of the nanovoids is decreased and a density of the nanovoids is increased in the electroactive element, wherein the electroactive device is positioned at a distance from a user's eye, and (2) emitting image light from an emissive device positioned such that at least a portion of the image light is incident on a surface of the electroactive device facing the user's eye.

A Distributed light projection device, including: one or a plurality of waveguides; and above each waveguide, a plurality of extraction cells coupled to distinct portions of the guide, each extraction cell including first and second stacked diffraction gratings.

A wafer includes a number of die, with each die including electronic integrated circuits and optical devices. The wafer has a top surface and a bottom surface and a base layer. The bottom surface of the wafer corresponds to a bottom surface of the base layer. A wafer support system is attached to the top surface of the wafer. A thickness of the base layer is removed to expose a target layer within the wafer and to give the wafer a new bottom surface. A replacement handle structure is attached to the new bottom surface of the wafer. The replacement handle structure includes a first thickness region and a second thickness region. The first thickness region is positioned closest to the new bottom surface. The first thickness region is formed of an optical cladding material that mitigates optical coupling between optical devices within the die and the replacement handle structure.

A device disclosed herein includes a display alignment sensing assembly positioned to receive a first signal output from a first display assembly and a second signal output from a second display assembly. A waveguide directs the second signal from the output of the second display assembly to the display alignment sensing assembly where the first signal and the second signal are merged into a combined signal received at an optical sensor. A display alignment tracker detects a positioning disparity between the first signal and the second signal within the combined signal and outputs a rendering position adjustment instruction to correct for the detected positioning disparity.

A grating coupler having first and second ends for coupling a light beam to a waveguide of a chip includes a substrate configured to receive the light beam from the first end and transmit the light beam through the second end, the substrate having a first refractive index n1, a grating structure having curved grating lines arranged on the substrate, the grating structure having a second refractive index n1, wherein the curved grating lines have line width w and height d and are arranged by a pitch Λ, wherein the second refractive index n2 is less than first refractive index n1, and a cladding layer configured to cover the grating structure, wherein the cladding layer has a third refractive index n3. The curves of the grating lines are constructed such that the emitting beam is shaped for efficient coupling to another optical component. The curves can also be tilted to reduce coupling back into the waveguide.

A grating coupler having first and second ends for coupling a light beam to a waveguide of a chip includes a substrate configured to receive the light beam from the first end and transmit the light beam through the second end, the substrate having a first refractive index n1, a grating structure having curved grating lines arranged on the substrate, the grating structure having a second refractive index n1, wherein the curved grating lines have line width w and height d and are arranged by a pitch Λ, wherein the second refractive index n2 is less than first refractive index n1, and a cladding layer configured to cover the grating structure, wherein the cladding layer has a third refractive index n3. The curves of the grating lines are constructed such that the emitting beam is shaped for efficient coupling to another optical component. The curves can also be tilted to reduce coupling back into the waveguide.

A method of fabricating a multilayer dielectric (MLD) diffraction grating by providing a multilayer stack having a grating layer, and anisotropically etching the grating layer to form grating lines having an initial lineheight, an initial linewidth, and an initial grating duty cycle, that are greater than a target lineheight, a target linewidth, and a target grating duty cycle, respectively. An isotropic wet etch solution is then used to etch back the grating lines to the target lineheight, the target linewidth, and the target grating duty cycle so as to minimize electric field intensities and maximize diffraction efficiency for a given set of MLD illumination conditions.

Structures including a waveguide core and methods of fabricating a structure including a waveguide core. The structure comprises a substrate, a waveguide core, and a grating disposed in a vertical direction between the waveguide core and the substrate. The grating includes a first plurality of layers and a second plurality of layers that alternate in the vertical direction with the first plurality of layers. The first plurality of layers comprise a first material having a first refractive index, and the second plurality of layers comprise a second material having a second refractive index that is greater than the first refractive index.

Structures including a waveguide core and methods of fabricating a structure including a waveguide core. The structure comprises a substrate, a waveguide core, and a grating disposed in a vertical direction between the waveguide core and the substrate. The grating includes a first plurality of layers and a second plurality of layers that alternate in the vertical direction with the first plurality of layers. The first plurality of layers comprise a first material having a first refractive index, and the second plurality of layers comprise a second material having a second refractive index that is greater than the first refractive index.