Abstract: This technology relates to a display mounted messaging system. The display mounted messaging system may include a light emitting diode (LED) display attached to a housing of a sensor. The housing of the sensor may rotate. The display mounted messaging system may also include an LED controller which is configured to selectively activate and deactivate at least one LED in the LED display, to provide a message in the direction of an intended recipient.

Abstract: Example embodiments relate to controlling detection time in photodetectors. An example embodiment includes a device. The device includes a substrate. The device also includes a photodetector coupled to the substrate. The photodetector is arranged to detect light emitted from a light source that irradiates a top surface of the device. A depth of the substrate is at most 100 times a diffusion length of a minority carrier within the substrate so as to mitigate dark current arising from minority carriers photoexcited in the substrate based on the light emitted from the light source.

Abstract: The present disclosure relates to optical systems and methods of their operation. An example optical system includes an optical component and one or more light sources configured to emit a light signal. The light signal interacts with the optical component so as to provide an interaction light signal. The optical system also includes a detector configured to detect at least a portion of the interaction light signal as a detected light signal. The optical system additionally includes a controller configured to carry out operations including causing the one or more light sources to emit the light signal and receiving the detected light signal from the detector. The operations also include determining, based on the detected light signal, that one or more defects are associated with the optical component.

Abstract: Example embodiments relate to calibration systems for light detection and ranging (lidar) devices. An example calibration system includes a calibration target that includes a surface having at least one characterized reflectivity. The surface is configured to receive one or more calibration signals emitted by a lidar device along one or more optical axes when the lidar device is separated from the calibration target by an adjustable distance. The calibration system also includes at least one lens that modifies the one or more calibration signals. In addition, the system includes an adjustable attenuator configured to attenuate each of the one or more calibration signals to simulate, in combination with the at least one lens, a distance that is greater than the adjustable distance. Further, the system includes a calibration controller configured to analyze data associated with detected reflections of the one or more calibration signals.

Abstract: A light detection and ranging (LIDAR) device includes a light emitter configured to emit light pulses into a field of view and a detector configured to detect light in the field of view. The light emitter emits a first light pulse. The detector detects, during a first measurement period, at least one reflected light pulse that is indicative of reflection by a retroreflector based on a shape of a reflected light pulse, a magnitude of a reflected light pulse, and/or a time separation between two reflected light pulses. In response to detecting the at least one reflected light pulse indicative of reflection by a retroreflector, the light emitter is deactivated for one or more subsequent measurement periods. Additionally, the LIDAR device may inform one or more other LIDAR devices by transmitting to a computing device information indicative of the retroreflector being within the field of view of the light emitter.

Abstract: Example embodiments relate to communication links, computing systems, and methods for their use. An example embodiment includes a communication link. The communication link includes a low-voltage differential signaling (LVDS) driver. The LVDS driver is configured to provide a differential signal that is based on a digital bit stream. The digital bit stream includes a series of digital bits that are temporally arranged based on a nominal bit period. The communication link also includes a controllable delay device. The controllable delay device is configured to provide a delay signal to the LVDS driver so as to cause a rising edge or a falling edge of respective digital bits to vary in time with respect to the nominal bit period based on a predetermined sequence of delay amounts. The delay amounts represent positive and negative differences in time from the nominal bit period.

Abstract: A method includes applying, by a switching circuit, pulses of an input voltage to an input of an inductor. The method includes charging, in accordance with an off state of a switch, a charge storage device through the inductor using the pulses of the input voltage such that the circuit node develops a charge voltage that is greater than the input voltage. The method includes discharging, in accordance with an on state of the switch, the charge storage device such that a first portion of the charge voltage is applied to a light emitter and a second portion of the charge voltage is applied to parasitic inductance. The method includes controlling, by a controller, a timing of the pulses of the input voltage applied by the switching circuit based on a parasitic inductance from a previous charging cycle of the charge storage device, so as to control the charge voltage.

Abstract: In one example, a LIDAR device includes a light sources that emits light and a transmit lens that directs the emitted light to illuminate a region of an environment with a field-of-view defined by the transmit lens. The LIDAR device also includes a receive lens that focuses at least a portion of incoming light propagating from the illuminated region of the environment along a predefined optical path. The LIDAR device also includes an array of light detectors positioned along the predefined optical path. The LIDAR device also includes an offset light detector positioned outside the predefined optical path. The LIDAR device also includes a controller that determines whether collected sensor data from the array of light detectors includes data associated with another light source different than the light source of the device based on output from the offset light detector.

Abstract: Example embodiments relate to controlling detection time in photodetectors. An example embodiment includes a device. The device includes a substrate. The device also includes a photodetector coupled to the substrate. The photodetector is arranged to detect light emitted from a light source that irradiates a top surface of the device. A depth of the substrate is at most 100 times a diffusion length of a minority carrier within the substrate so as to mitigate dark current arising from minority carriers photoexcited in the substrate based on the light emitted from the light source.

Abstract: A light detection and ranging (LIDAR) system can emit light toward an environment and detect responsively reflected light to determine a distance to one or more points in the environment. The reflected light can be detected by a plurality of plurality of photodiodes that are reverse-biased using a high voltage. Signals from the plurality of reverse-biased photodiodes can be amplified by respective transistors and applied to an analog-to-digital converter (ADC). The signal from a particular photodiode can be applied to the ADC by biasing a respective transistor corresponding to the particular photodiode while not biasing transistors corresponding to other photodiodes. The gain of each photodiode/transistor pair can be controlled by adjusting the bias voltage applied to each photodiode using a digital-to-analog converter. The gain of each photodiode/transistor pair can be controlled based on the detected temperature of each photodiode.

Abstract: The present disclosure relates to devices, lidar systems, and vehicles that include optical redirectors. An example lidar system includes a transmitter and a receiver. The transmitter includes at least one light-emitter device configured to transmit emission light into an environment. The receiver is configured to detect return light from the environment and includes a plurality of apertures, a plurality of photodetectors, and a plurality of optical redirectors. Each optical redirector is configured to optically couple a respective portion of return light from a respective aperture to at least one photodetector of the plurality of photodetectors. Each optical redirector also has a rotational orientation relative to other optical redirectors such that the redirection paths of optical redirectors that correspond to adjacent apertures are not coplanar with one another.

Abstract: Example embodiments relate to crosstalk reduction for light detection and ranging (lidar) devices using wavelength locking. An example embodiment includes a lidar device. The lidar device includes a first light emitter configured to emit a first light signal and a second light emitter configured to emit a second light signal. The lidar device also includes a first light guide and a second light guide. In addition, the lidar device includes a first light detector and a second light detector. Further, the lidar device includes a first wavelength-locking mechanism configured to use a portion of the first light signal to maintain a wavelength of the first light signal and a second wavelength-locking mechanism configured to use a portion of the second light signal to maintain a wavelength of the second light signal. The wavelengths of the first light signal and the second light signal are different.

Abstract: One example device comprises a plurality of emitters including at least a first emitter and a second emitter. The first emitter emits light that illuminates a first portion of a field-of-view (FOV) of the device. The second emitter emits light that illuminates a second portion of the FOV. The device also comprises a controller that obtains a scan of the FOV. The controller causes each emitter of the plurality of emitters to emit a respective light pulse during an emission time period associated with the scan. The controller causes the first emitter to emit a first-emitter light pulse at a first-emitter time offset from a start time of the emission time period. The controller causes the second emitter to emit a second-emitter light pulse at a second-emitter time offset from the start time of the emission time period.

Abstract: Described herein is a LIDAR device that may include a transmitter, first and second receivers, and a rotating platform. The transmitter may be configured to emit light having a vertical beam width. The first receiver may be configured to detect light at a first resolution while scanning the environment with a first FOV and the second receiver may be configured to detect light at a second resolution while scanning the environment with a second FOV. In this arrangement, the first resolution may be higher than the second resolution, the first FOV may be at least partially different from the second FOV, and the vertical beam width may encompass at least a vertical extent of the first and second FOVs. Further, the rotating platform may be configured to rotate about an axis such that the transmitter and first and second receivers each move based on the rotation.

Abstract: Example implementations are provided for an arrangement of co-aligned rotating sensors. One example device includes a light detection and ranging (LIDAR) transmitter that emits light pulses toward a scene according to a pointing direction of the device. The device also includes a LIDAR receiver that detects reflections of the emitted light pulses reflecting from the scene. The device also includes an image sensor that captures an image of the scene based on at least external light originating from one or more external light sources. The device also includes a platform that supports the LIDAR transmitter, the LIDAR receiver, and the image sensor in a particular relative arrangement. The device also includes an actuator that rotates the platform about an axis to adjust the pointing direction of the device.

Abstract: This technology relates to a display mounted messaging system. The display mounted messaging system may include a light emitting diode (LED) display attached to a housing of a sensor. The housing of the sensor may rotate. The display mounted messaging system may also include an LED controller which is configured to selectively activate and deactivate at least one LED in the LED display, to provide a message in the direction of an intended recipient.

Abstract: An example circuit includes a light detector and a biasing capacitor having (i) a first terminal that applies to the light detector an output voltage that can either bias or debias the light detector and (ii) a second terminal for controlling the output voltage. The circuit includes a first transistor connected to the second terminal of the biasing capacitor and configured to drive the output voltage to a first voltage level above a biasing threshold of the light detector and thereby biasing the light detector. The circuit includes a second transistor connected to the second terminal of the biasing capacitor and configured to drive the output voltage to a second voltage level below the biasing threshold of the light detector and thereby debiasing the light detector. The second voltage is a non-zero voltage that corresponds to a charge level of the biasing capacitor.

Abstract: The present disclosure relates to limitation of noise on light detectors using an aperture. One example embodiment includes a system. The system includes a lens disposed relative to a scene and configured to focus light from the scene onto a focal plane. The system also includes an aperture defined within an opaque material disposed at the focal plane of the lens. The aperture has a cross-sectional area. In addition, the system includes an array of light detectors disposed on a side of the focal plane opposite the lens and configured to intercept and detect diverging light focused by the lens and transmitted through the aperture. A cross-sectional area of the array of light detectors that intercepts the diverging light is greater than the cross-sectional area of the aperture.

Abstract: A laser diode firing circuit for a light detection and ranging device is disclosed. The firing circuit includes a laser diode coupled in series to a transistor, such that current through the laser diode is controlled by the transistor. The laser diode is configured to emit a pulse of light in response to current flowing through the laser diode. The firing circuit includes a capacitor that is configured to charge via a charging path that includes an inductor and to discharge via a discharge path that includes the laser diode. The transistor controlling current through the laser diode can be a Gallium nitride field effect transistor.