Abstract: Configurations for display stacks of an electronic device and methods for mitigating crosstalk are disclosed. The display stack may include a transceiver module, which may be located under or behind the display. The transceiver module may include a transmitter module, which may provide polarized light from the transmitter that may suppress module crosstalk. The transceiver module also may include a receiver module, which may include polarization control elements and an analyzer for differentiating between a target signal and a crosstalk signal. The polarization control on both the transmitter module and receiver module sides may suppress the crosstalk signals, which may be due to the reflections between and within the elements of the display stack and resulting from positioning the transceiver module behind the display.

Abstract: A wearable device includes a device housing configured to be worn on a first surface of a user, a set of one or more SMI sensors, and a processor. The set of one or more SMI sensors is mounted within the device housing and configured to emit a set of one or more beams of electromagnetic radiation, with each beam emitted in a different direction extending away from the first surface. The set of one or more SMI sensors is also configured to generate a set of one or more SMI signals containing information about a relationship between the device housing and a second surface. The processor is configured to extract the relationship between the device housing and the second surface from digitized samples of the set of one or more SMI signals.

Abstract: Disclosed herein are structures, devices, and systems for detecting touch and force inputs at multiple sensing locations on a surface of an electronic device using waveguide-based interferometry. A laser light source, such as a VCSEL, inserts light into a waveguide positioned adjacent to the sensing locations, and an input at a sensing location alters the inserted light in the waveguide allowing for determination of the input's touch or force at the sensing location. Wavelength modulation of the inserted light allows isolation in frequency of the signals from each sensing location. Optical phase locking can be used to lock an absolute distance beat frequency corresponding to a stationary reference point in the waveguide.

Abstract: A photovoltaic device includes a first contact and a hybrid absorber layer. The hybrid absorber layer includes a chalcogenide layer and a semiconductor layer in contact with the chalcogenide layer. A buffer layer is formed on the absorber layer, and a transparent conductive contact layer is formed on the buffer layer.

Abstract: A sensor system includes a self-mixing interferometry sensor; a drive circuit configured to apply a modulated drive signal to an input of the self-mixing interferometry sensor; a mixer circuit configured to mix a modulated output of the self-mixing interferometry sensor with a local oscillator signal that is orthogonal to the modulated drive signal over a period of time; an integrator circuit configured to integrate an output of the mixer circuit over the period of time; and a processor configured to determine, using an output of the integrator circuit, at least one of a round-trip propagation time of electromagnetic radiation emitted by the self-mixing interferometry sensor and reflected back into the self-mixing interferometry sensor by an object or medium, or a velocity of the object or medium.

Abstract: An electronic device includes a housing and a display. The housing defines an interior cavity and includes an optically-transmissive housing component. The display is disposed in the interior cavity and is viewable through the optically-transmissive housing component. An optoelectronic component is disposed in the interior cavity. An optical fiber extends between a first end positioned adjacent the optoelectronic component and a second end positioned adjacent the optically-transmissive housing component. The optical fiber defines a non-linear optical path between the first end and the second end. At least a portion of the optical fiber is laterally offset from a lateral edge of the display.

Abstract: In some embodiments, a device includes a light-emitting display, and an optical emitter positioned behind the light-emitting display. The optical emitter is configured to emit light through the light-emitting display. A processor is configured to synchronize a first illumination timing of the optical emitter and a second illumination timing of the light-emitting display. In some embodiments, a device includes an optical transceiver processor and a display processor. The display processor is configured to output timing information to a light-emitting display and to the optical transceiver processor, and the optical transceiver processor is configured to cause an optical transceiver to emit or receive light in synchronization with the timing information output by the display processor.

Abstract: A finger device may be worn on a user's finger and may serve as a controller for a head-mounted device or other electronic device. The finger device may have a housing having an upper housing portion that extends across a top of the finger and first and second side housing portions that extend down respective first and second sides of the finger. Displacement sensors in the side housing portions may measure movements of the sides of the finger as the finger contacts an external surface. To account for variations in skin compliance, the finger device and/or the electronic device may store calibration data that maps displacement values gathered by the displacement sensors to force values. The calibration data may be based on calibration measurements gathered while the user's finger wearing the finger device contacts a force sensor in an external electronic device.

Abstract: A sensor system includes a self-mixing interferometry sensor; a drive circuit configured to apply a modulated drive signal to an input of the self-mixing interferometry sensor; a mixer circuit configured to mix a modulated output of the self-mixing interferometry sensor with a local oscillator signal that is orthogonal to the modulated drive signal over a period of time; an integrator circuit configured to integrate an output of the mixer circuit over the period of time; and a processor configured to determine, using an output of the integrator circuit, at least one of a round-trip propagation time of electromagnetic radiation emitted by the self-mixing interferometry sensor and reflected back into the self-mixing interferometry sensor by an object or medium, or a velocity of the object or medium.

Abstract: Configurations for display stacks of an electronic device and methods for mitigating crosstalk are disclosed. The display stack may include a transceiver module, which may be located under or behind the display. The transceiver module may include a transmitter module, which may provide polarized light from the transmitter that may suppress module crosstalk. The transceiver module also may include a receiver module, which may include polarization control elements and an analyzer for differentiating between a target signal and a crosstalk signal. The polarization control on both the transmitter module and receiver module sides may suppress the crosstalk signals, which may be due to the reflections between and within the elements of the display stack and resulting from positioning the transceiver module behind the display.

Abstract: Disclosed herein are electronic devices having touch input surfaces. A user's touch input or press on the touch input surface is detected using a set of lasers, such as vertical-cavity surface-emitting lasers (VCSELs) that emit beams of light toward the touch input surface. The user's touch causes changes in the self-mixing interference within the VCSEL of the emitted light with reflected light, such as from the touch input surface. Deflection and movement (e.g., drag motion) of the user's touch is determined from detected changes in the VCSELs' operation due to the self-mixing interference.

Abstract: An optical sensing system can be integrated into a camera module. In particular, an optical element of an optical sensing system can be disposed entirely or partly within a barrel of a camera module. The optical element can be oriented toward a reflective surface, such as an infrared cut filter, such that an optical path is defined between free space and the optical element via at least one reflection off the reflective surface.

Abstract: An electronic watch includes a housing, a user-operable watch crown mounted to the housing, an electromagnetic radiation source emitting a beam of electromagnetic radiation toward a watch crown surface, and a sensor. The beam of electromagnetic radiation depends on a coherent mixing of electromagnetic radiation within a resonant cavity of the electromagnetic radiation source. The coherent mixing includes a mixing of a first amount of electromagnetic radiation generated by the electromagnetic radiation source and a second amount of electromagnetic radiation redirected into the resonant cavity by the watch crown surface. The sensor measures a first parameter of the beam of electromagnetic radiation and determines, using the measurement of the first parameter, a value of a second parameter characterizing movement of the watch crown. The second parameter may include a direction of rotation or speed of rotation of the watch crown, or other parameters.

Abstract: An electronic device includes a housing and a display. The housing defines an interior cavity and includes an optically-transmissive housing component. The display is disposed in the interior cavity and is viewable through the optically-transmissive housing component. An optoelectronic component is disposed in the interior cavity. An optical fiber extends between a first end positioned adjacent the optoelectronic component and a second end positioned adjacent the optically-transmissive housing component. The optical fiber defines a non-linear optical path between the first end and the second end. At least a portion of the optical fiber is laterally offset from a lateral edge of the display.

Abstract: Disclosed herein are electronic devices having touch input surfaces. A user's touch input or press on the touch input surface is detected using a set of lasers, such as vertical-cavity surface-emitting lasers (VCSELs) that emit beams of light toward the touch input surface. The user's touch causes changes in the self-mixing interference within the VCSEL of the emitted light with reflected light, such as from the touch input surface. Deflection and movement (e.g., drag motion) of the user's touch is determined from detected changes in the VCSELs' operation due to the self-mixing interference.

Abstract: An optical sensing system can be integrated into a camera module. In particular, an optical element of an optical sensing system can be disposed entirely or partly within a barrel of a camera module. The optical element can be oriented toward a reflective surface, such as an infrared cut filter, such that an optical path is defined between free space and the optical element via at least one reflection off the reflective surface.

Abstract: An optical sensing system includes a transmitter side and a receiver side, and is configured to be positioned below a display of an electronic device. The transmitter side includes a light emitter, a temperature sensor, and a photodiode. The receiver side includes a photodiode and a temperature sensor. The optical sensing system includes an application-specific integrated circuit that leverages the temperature sensors, the photodiodes, and one or more signal filters such as a high-pass filter to perform multiple field calibrations of the optical sensing system, thereby improving accuracy and precision thereof.

Abstract: In some embodiments, a device includes a light-emitting display, and an optical emitter positioned behind the light-emitting display. The optical emitter is configured to emit light through the light-emitting display. A processor is configured to synchronize a first illumination timing of the optical emitter and a second illumination timing of the light-emitting display. In some embodiments, a device includes an optical transceiver processor and a display processor. The display processor is configured to output timing information to a light-emitting display and to the optical transceiver processor, and the optical transceiver processor is configured to cause an optical transceiver to emit or receive light in synchronization with the timing information output by the display processor.

Abstract: Aspects of the subject technology relate to an apparatus for self-mixing particulate-matter sensing using a vertical-cavity surface-emitting laser (VCSEL) with extrinsic photodiodes. The apparatus includes a dual-emitting light source disposed on a first chip and to generate a first light beam and a second light beam. The first light beam illuminates a particulate matter (PM), and a light detector extrinsic to the first chip measures the second light beam and variations of the second light beam and generates a self-mixing signal. The variations of the second light beam are caused by a back-scattered light resulting from back-scattering of the first light beam from the PM. The light detector is coupled to the dual-emitting light source. The direction of the second light beam is opposite to the direction of the first light beam, and the second light beam is directed to a sensitive area of the light detector.

Abstract: In some embodiments, a display stack includes a set of light-emitting elements, and a display backplane that includes a set of conductors and is electrically coupled to the set of light-emitting elements. A conductor in the set of conductors has a length, and a curved edge extending along at least a portion of the length. In some embodiments, a display stack includes a set of light-emitting elements; a set of transistors, electrically coupled to the set of light-emitting elements; and a set of conductors, electrically coupled to the set of transistors. The set of transistors may be electrically coupled to the set of conductors at a set of conductive pads. A plurality of conductive pads in the set of conductive pads is coupled to a single conductor in the set of conductors. The single conductor approaches different conductive pads in the plurality of conductive pads at different angles.