Abstract: An optical coupling device can couple incident light from a fiber into waveguides, but can reduce the coupling of return light from the waveguides into the fiber. A Faraday rotator layer can rotate by forty-five degrees, with a first handedness, respective planes of polarization of incident beams, and can rotate by forty-five degrees, with a second handedness opposite the first handedness, respective planes of polarization of return beams. A redirection layer can include at least one grating coupler that can redirect an incident beam of one polarization so that the redirected path extends within the redirection layer toward a first waveguide, and can redirect an incident beam of an opposite polarization so that the redirected path extends within the redirection layer toward a second waveguide. An optional birefringent layer can spatially separate incident beam having different polarizations, so that two single-polarization grating couplers can be used.

Abstract: Measurement apparatuses and methods are disclosed for generating high-precision and -accuracy gas concentration maps that can be overlaid with 3D topographic images by rapidly scanning one or several modulated laser beams with a spatially-encoded transmitter over a scene to build-up imagery. Independent measurements of the topographic target distance and path-integrated gas concentration are combined to yield a map of the path-averaged concentration between the sensor and each point in the image. This type of image is particularly useful for finding localized regions of elevated (or anomalous) gas concentration making it ideal for large-area leak detection and quantification applications including: oil and gas pipeline monitoring, chemical processing facility monitoring, and environmental monitoring.

Abstract: Novel small-footprint integrated photonics optical gyroscopes disclosed herein can provide ARW in the range of 0.05°/?Hr or below (e.g. as low as 0.02°/?Hr), which makes them comparable to fiber optic gyroscopes (FOGs) in terms of performance, at a much lower cost. The low bias stability value in the integrated photonics optical gyroscope corresponds to a low bias estimation error (in the range of 1.5°/Hr or even lower) that is crucial for safety-critical applications, such as calculating heading for autonomous vehicles, drones, aircrafts etc. The integrated photonics optical gyroscopes may be co-packaged with mechanical gyroscopes into a hybrid inertial measurement unit (IMU) to provide high-precision angular measurement for one or more axes.

Abstract: An integrated photonics optical gyroscope fabricated on a silicon nitride (SiN) waveguide platform comprises (SiN) waveguide-based optical components that constitute a front-end chip to launch light into and receive light from the rotation sensing element, that can be a fiber spool. The SiN waveguide-based components can be distributed between multiple layers that are stacked together to have a multi-layer configuration vertically and evanescently coupled with each other. External elements (e.g., laser, detectors, phase shifter) may be made of different material platform than SiN and can be hybridly integrated or otherwise coupled to the SiN waveguide platform. The phase shifters can be made of electro-optic material, or piezo-electric material or can be thermal phase shifters.

Abstract: A luminaire for providing configurable static lighting or dynamically-adjustable lighting. The luminaire uses an array of focusing elements that act on light provided via a corresponding array of sources or via an edge-lit lightguide. Designs are provided for adjusting the number of distinct beams produced by the luminaire, as well as the angular width, angular profile, and pointing angle of the beams. Designs are also provided for systems utilizing the adjustable luminaires in various applications.

Abstract: A device and system for non-invasively measuring wavelength-dependent changes in optical absorption of brain tissue damaged by CTE, TBI, concussion, repetitive trauma, and/or Lou Gehrig's disease in comparison to signals from healthy normal tissue for a subject in vivo. The brain, tissues, and fluids superficial to the brain are trans-cranially illuminated by light source(s) in low-absorption spectral windows for tissue in the visible and/or near-infrared parts of the spectrum. Optode(s) are disposed at predetermined radial distance(s) from a light output to collect the scattered and/or deflected signal from the surface of the head. The predetermined radial distance from the light output to the optode is correlated with the depth of tissue penetration for the light collected by the optode. A spectrometer and computer analyze the collected light for characteristic optical signatures of the brain tissue damage utilizing the absorbance and/or reflectance and/or transmission spectra generated as a result.

Abstract: Disclosed herein are configurations and methods to produce very low loss waveguide structures, which can be single-layer or multi-layer. These waveguide structures can be used as a sensing component of a small-footprint integrated optical gyroscope. By using pure fused silica substrates as both top and bottom cladding around a SiN waveguide core, the propagation loss can be well below 0.1 db/meter. Low-loss waveguide-based gyro coils may be patterned in the shape of a spiral (circular or rectangular or any other shape), that may be distributed among one or more of vertical planes to increase the length of the optical path while avoiding the increased loss caused by intersecting waveguides in the state-of-the-art designs. Low-loss adiabatic tapers may be used for a coil formed in a single layer where an output waveguide crosses the turns of the spiraling coil.

Abstract: The present disclosure relates to integrated photonics-based optical gyroscopes with silicon nitride (SiN) waveguide-based microresonators. SiN microresonators are fabricated either on a fused silica platform or on a silicon substrate with oxide cladding. A narrow linewidth high-Q laser is hybridly integrated on a silicon photonics platform. The laser is tuned with a first SiN microresonator, and the rotational sensing component of the gyroscope comprises another SiN microresonator. The silicon photonics front-end chip has components for a balanced detection scheme to cancel noise in the optical signal coming back from the rotational sensing component.

Abstract: Described herein are methods, systems, and apparatuses to utilize an electro-optic modulator including one or more heating elements. The modulator can utilize one or more heating elements to control an absorption or phase shift of the modulated optical signal. At least the active region of the modulator and the one or more heating elements of the modulator are included in a thermal isolation region comprising a low thermal conductivity to thermally isolate the active region and the one or more heating elements from a substrate of the PIC.

Abstract: Space division multiplexers can include adapters between multicore fibers with different core patterns and/or add-drop multiplexers for multicore fibers.

Abstract: Examples of FMCW laser radar systems and methods described herein may segment the processing of a broader bandwidth frequency chirp into multiple shorter-duration (e.g., lower bandwidth) frequency chirps. This segmentation may have the benefits in some examples of improving the measurement duty cycle and range resolution, and/or allowing for more flexible processing, and/or enabling improved detection of more distant objects.

Abstract: A method for generating frequency converted laser radiation is disclosed. The disclosure provides a method enabling generation of a frequency converted wavelength division multiplexed light source that is easy to implement at low cost. Adjustment of the center frequency and the mode spacing in a frequency converted wavelength division multiplexed light source is also disclosed.

Abstract: The wavelength response of an arrayed waveguide grating can be tuned, in accordance with various embodiments, using a beam sweeper including one or more heaters to shift a lateral position of light focused by the beam sweeper at an interface of the beam sweeper with an input free propagation region of the arrayed waveguide grating.

Abstract: Described herein are optical sensing devices for photonic integrated circuits (PICs). A PIC may comprise a plurality of waveguides formed in a silicon on insulator (SOI) substrate, and a plurality of heterogeneous lasers, each laser formed from a silicon material of the SOI substrate and to emit an output wavelength comprising an infrared wavelength. Each of these lasers may comprise a resonant cavity included in one of the plurality of waveguides, and a gain material comprising a non-silicon material and adiabatically coupled to the respective waveguide. A light directing element may direct outputs of the plurality of heterogeneous lasers from the PIC towards an object, and one or more detectors may detect light from the plurality of heterogeneous lasers reflected from or transmitted through the object.

Abstract: A system for reading and reporting data from a production of an alcoholic beverage includes a data capture device having a sensor end for placement within a liquid. The sensor end has at least two sensors for measuring data related to the liquid. A transmitter located within the data capture device is coupled to the at least two sensors and the transmitter periodically transmits the data related to the liquid. Color transmission or reflection of the liquid is used to measure clarity, color of the liquid, and relative sugar content.

Abstract: Optical switch trees are commonly used to route light from one input channel to multiple possible output channels one at a time. As the number of output channels increases, the number of wire-bonding pads increases and the drive electronics becomes more complicated. The optical switch tree comprises an array of optical switches arranged in a plurality of rows of optical switches, each connected by a row bus, which are connected to a first multiplexer and a common power source; and a plurality of columns of optical switches, each connected by a column bus, which are connected to a second multiplexer and a common ground. A control processor selects one of the plurality of columns of optical switches to connect to the common ground, and selects one of the plurality of rows of optical switches to connect to the common power source, thereby selecting a single optical switch in the array of optical switches to activate.

Abstract: Methods, devices, and systems for double-sided cooling of laser diodes are provided. In one aspect, a laser diode assembly includes a first heat sink, a plurality of submounts spaced apart from one another on the first heat sink, a plurality of laser diodes, and a second heat sink on top sides of the plurality of laser diodes. Each laser diode includes a corresponding active layer between a first-type doped semiconductor layer and a second-type doped semiconductor layer. A bottom side of each laser diode is positioned on a different corresponding submount of the plurality of submounts. The plurality of laser diode are electrically connected in series.

Abstract: A display system for a welding helmet that includes a darkening filter layer, a high-dynamic range (HDR) camera system to capture an HDR light field, and an optical image stabilization subsystem. Captured images are displayed on an HDR electronic display within the welding helmet without risk of overexposure of ultraviolet radiation to the operator. In some examples, dual electronic displays are used to display different HDR images to each eye of the operator.

Abstract: A light emitting device and a manufacturing method thereof are provided. The light emitting device includes a light emitting unit, a fluorescent layer, a reflective layer, and a light-absorbing layer. The light emitting unit has a top surface, a bottom surface opposite to the top surface, and a side surface located between the top surface and the bottom surface. The light emitting unit includes an electrode disposed at the bottom surface. The fluorescent layer is disposed on the top surface of the light emitting unit. The reflective layer covers the side surface of the light emitting unit. The light-absorbing layer covers the reflective layer, so that the reflective layer is located between the side surface of the light emitting unit and the light-absorbing layer.