Structures for a photonics chip, testing methods for a photonics chip, and methods of forming a structure for a photonics chip. A photonics chip includes a first waveguide, a second waveguide, an optical tap coupling the first waveguide to the second waveguide, and a photodetector coupled to the second waveguide. A laser is attached to the photonics chip. The laser is configured to generate laser light directed by the first waveguide to the optical tap.

An optical grating coupler defining an axis and configured to couple light between a planar waveguide and an optical fiber, including first and second entry surfaces and a plurality of scattering regions symmetric to the axis and arranged such scattering strength presented to incoming light by the plurality of scattering regions changes from weak to strong along a beam path of the incoming light to match a Gaussian mode profile of the optical fiber.

The disclosed projector device may include (1) a first monochromatic emitter array having a plurality of emitters of a first color disposed in a two-dimensional configuration and (2) a second monochromatic emitter array having a plurality of emitters of a second color disposed in a two-dimensional configuration. The first and second monochromatic emitter arrays may be configured to emit images of the first and second colors into a waveguide configuration, and the first color may be different than the second color. Associated display systems and methods are also provided.

An optical bandpass filter includes an optical splitter having at least four ports, one of the ports being designated as an input port and one of the ports being designated as an output port. First and second reflectors couple with respective third and fourth ones of the ports. The splitter directs portions of the input light from the input port, into the third and fourth ports, such that the portions of the input light propagate toward the respective first and second reflectors. The first and second reflectors reflect light having wavelengths within a predetermined wavelength range, back toward the splitter, as wavelength-selected light, and transmit light having wavelengths that are outside of the predetermined wavelength range, away from the splitter. The splitter directs at least a portion of the wavelength-selected light that propagates back toward the splitter, into the output port, as output light.

The disclosed projector device may include (1) a first monochromatic emitter array having a plurality of emitters of a first color disposed in a two-dimensional configuration and (2) a second monochromatic emitter array having a plurality of emitters of a second color disposed in a two-dimensional configuration. The first and second monochromatic emitter arrays may be configured to emit images of the first and second colors into a waveguide configuration, and the first color may be different than the second color. Associated display systems and methods are also provided.

According to one embodiment, a display device includes a first arrangement layer and a second arrangement layer. The first layer includes a first pixel, a second pixel, and a third pixel are arranged periodically in one direction. The second layer is opposed to the first layer, and the second layer includes a first element, a second element, and a third element which are arranged periodically to correspond to the first pixel, the second pixel, and the third pixel, respectively, and separate emission light to light of wavelength corresponding to a first color, light of wavelength corresponding to a second color, and light of wavelength corresponding to a third color to be emitted on the first pixel, the second pixel, and the third pixel, respectively.

A semiconductor optical device includes a substrate containing silicon and including terraces, a waveguide, and a diffraction grating in different regions in plan view; and a semiconductor device formed of a III-V compound semiconductor and having an optical gain, the semiconductor device being joined to the diffraction grating and the terraces and being in contact with an upper surface of the substrate. The waveguide is optically coupled to the diffraction grating in a direction in which the waveguide extends. The terraces are located on both sides of the waveguide and the diffraction grating in a direction crossing the direction in which the waveguide extends. The substrate has a groove between each of the terraces and the waveguide. The diffraction grating is continuously connected to the terraces in the direction crossing the direction in which the waveguide extends.

A display system comprises a waveguide having light incoupling or light outcoupling optical elements formed of a metasurface. The metasurface is a multilevel (e.g., bi-level) structure having a first level defined by spaced apart protrusions formed of a first optically transmissive material and a second optically transmissive material between the protrusions. The metasurface also includes a second level formed by the second optically transmissive material. The protrusions on the first level may be patterned by nanoimprinting the first optically transmissive material, and the second optically transmissive material may be deposited over and between the patterned protrusions. The widths of the protrusions and the spacing between the protrusions may be selected to diffract light, and a pitch of the protrusions may be 10-600 nm.

A screen includes a transparent base body with a front face and a rear face, and an image sensor. The base body includes a coupling-in region and a coupling-out region at a distance therefrom in a first direction. The coupling-in region includes a diffractive structure which deflects only part of the radiation incident on the front face and originating from an object to be detected, such that the deflected part is propagated as coupled-in radiation in the base body by reflection, until it reaches the coupling-out region and is incident on said coupling-out region, and the coupling-out region deflects at least part of said incident coupled-in radiation, such that the deflected part exits the base body via the front face or the rear face and is incident on the image sensor.

A display system comprises a waveguide having light incoupling or light outcoupling optical elements formed of a metasurface. The metasurface is a multilevel (e.g., bi-level) structure having a first level defined by spaced apart protrusions formed of a first optically transmissive material and a second optically transmissive material between the protrusions. The metasurface also includes a second level formed by the second optically transmissive material. The protrusions on the first level may be patterned by nanoimprinting the first optically transmissive material, and the second optically transmissive material may be deposited over and between the patterned protrusions. The widths of the protrusions and the spacing between the protrusions may be selected to diffract light, and a pitch of the protrusions may be 10-600 nm.