Abstract: In one embodiment, a lidar system includes a light source configured to emit (i) local-oscillator light and (ii) pulses of light, where each emitted pulse of light is coherent with a corresponding portion of the local-oscillator light. The lidar system also includes a receiver configured to detect the local-oscillator light and a received pulse of light, the received pulse of light including light from one of the emitted pulses of light that is scattered by a target located a distance from the lidar system. The local-oscillator light and the received pulse of light are coherently mixed together at the receiver. The lidar system further includes a processor configured to determine the distance to the target based at least in part on a time-of-arrival for the received pulse of light.

Abstract: A lidar system includes one or more light sources configured to generate a first beam of light and a second beam of light, a scanner configured to scan the first and second beams of light across a field of regard of the lidar system, and a receiver configured to detect the first beam of light and the second beam of light scattered by one or more remote targets. The scanner includes a rotatable polygon mirror that includes multiple reflective surfaces angularly offset from one another along a periphery of the polygon mirror, the reflective surfaces configured to reflect the first and second beams of light to produce a series of scan lines as the polygon mirror rotates. The scanner also includes a pivotable scan mirror configured to (i) reflect the first and second beams of light and (ii) pivot to distribute the scan lines across the field of regard.

Abstract: In one embodiment, a lidar system includes a wavelength-tunable light source configured to emit pulses of light, each emitted pulse of light having a particular wavelength of multiple different wavelengths. The lidar system also includes a scanner configured to scan the emitted pulses of light across a field of regard of the lidar system. The scanner includes (i) a beam deflector configured to angularly deflect each emitted pulse of light along a first scan axis according to the particular wavelength of the emitted pulse of light and (ii) a scan mirror configured to scan the emitted pulses of light along a second scan axis different from the first scan axis. The lidar system further includes a receiver configured to detect a received pulse of light that includes a portion of one of the emitted pulses of light scattered by a target located a distance from the lidar system.

Abstract: To dynamically control power in a lidar system, a controller identifies a triggering event and provides a control signal to a light source in the lidar system adjusting the power of light pulses emitted by the light source. The triggering event includes identifying a particular type of object within a threshold distance of the lidar system. In some scenarios, the power is adjusted to address eye-safety concerns.

Abstract: In one embodiment, a method for dynamically varying receiver characteristics in a lidar system includes emitting light pulses by a light source in a lidar system. The method further includes detecting, by a receiver in the lidar system, light from one of the light pulses scattered by one or more remote targets to identify a return light pulse. The method also includes determining an atmospheric condition at or near a geolocation of a vehicle that includes the lidar system. The method further includes providing a control signal to the receiver adjusting one or more characteristics of the receiver to compensate for attenuation or distortion of the return light pulses associated with the atmospheric condition.

Abstract: In one embodiment, a lidar system includes a light source configured to emit pulses of light and a scanner configured to scan the emitted pulses of light along a high-resolution scan pattern located within a field of regard of the lidar system. The scanner includes one or more scan mirrors configured to (i) scan the emitted pulses of light along a first scan axis to produce multiple scan lines of the high-resolution scan pattern, where each scan line is associated with multiple pixels, each pixel corresponding to one of the emitted pulses of light and (ii) distribute the scan lines of the high-resolution scan pattern along a second scan axis. The high-resolution scan pattern includes one or more of: interlaced scan lines and interlaced pixels.

Abstract: To dynamically control power in a lidar system, a controller identifies a triggering event and provides a control signal to a light source in the lidar system adjusting the power of light pulses provided by the light source. Triggering events may include exceeding a threshold speed, being within a threshold distance of a person or other object, an atmospheric condition, identifying residue on a surface of a window of the lidar system, etc. In some scenarios, the power is adjusted to address eye-safety concerns.

Abstract: A lidar system includes one or more light sources configured to generate a first beam of light and a second beam of light, a scanner configured to scan the first and second beams of light across a field of regard of the lidar system, and a receiver configured to detect the first beam of light and the second beam of light scattered by one or more remote targets. The scanner includes a rotatable polygon mirror that includes multiple reflective surfaces angularly offset from one another along a periphery of the polygon mirror, the reflective surfaces configured to reflect the first and second beams of light to produce a series of scan lines as the polygon mirror rotates. The scanner also includes a pivotable scan mirror configured to (i) reflect the first and second beams of light and (ii) pivot to distribute the scan lines across the field of regard.

Abstract: In one embodiment, a lidar system includes a light source configured to emit pulses of light and a scanner configured to scan the emitted pulses of light across a field of regard of the lidar system. The scanner includes (i) a beam deflector configured to direct each emitted pulse of light along a first scan axis and (ii) a scan mirror configured to scan the emitted pulses of light along a second scan axis different from the first scan axis. The lidar system also includes a receiver that includes a one-dimensional detector array that includes multiple detector elements arranged along a direction corresponding to the first scan axis. The receiver is configured to (i) detect a received pulse of light that includes a portion of one of the emitted pulses of light scattered by a target and (ii) determine a time of arrival of the received pulse of light.

Abstract: A system includes a first lidar sensor and a second lidar sensor, where each lidar sensor includes a scanner configured to direct a set of pulses of light along a scan pattern and a receiver configured to detect scattered light from the set of light pulses. The scan patterns are at least partially overlapped in an overlap region. The system further includes an enclosure, where the first lidar sensor and the second lidar sensor are contained within the enclosure. Each scanner includes one or more mirrors, and each mirror is driven by a scan mechanism.

Abstract: Scanning lidar systems and methods for performing a redundant beam scan to reduce data loss resulting from obscurants are presented. An example system comprises a first light source and a second light source having a spatial displacement relative to the first light source. The example system also includes a mirror assembly and an optical window configured to transmit the light pulses emitted from the light sources, wherein the spatial displacement of the second light source relative to the first light source is such that the first and second light pulses produce two pixels corresponding to a same portion of an image. The example system also includes a receiver configured to receive the light pulses when scattered by one or more targets, the receiver including two or more detectors configured to detect at least one of the light pulses and output an electric signal for generating the two pixels.

Abstract: In one embodiment, a lidar system includes a light source configured to emit pulses of light, where each emitted pulse of light includes a spectral signature of multiple different spectral signatures. The lidar system also includes a receiver configured to detect a received pulse of light, the received pulse of light including light from one of the emitted pulses of light scattered by a target located a distance from the lidar system. The emitted pulse of light includes one of the spectral signatures. The receiver includes a detector configured to produce a photocurrent signal corresponding to the received pulse of light, a frequency-detection circuit configured to determine, based on the photocurrent signal, a spectral signature of the received pulse of light, and a pulse-detection circuit configured to determine, based on the photocurrent signal, a time-of-arrival of the received pulse of light.

Abstract: A machine vision system comprises a camera configured to generate one or more images of a field of regard of the camera, a lidar system, and a processor. The lidar system includes a laser configured to emit light, where the emitted light is directed toward a region within the field of regard of the camera and a receiver configured to detect light returned from the emitted light. The processor is configured to receive an indication of a location based on the returned light and determine, based on the one or more images generated by the camera, whether the indication of the location is associated with a spurious return.

Abstract: A lidar system includes one or more light sources configured to generate a first beam of light and a second beam of light, a scanner configured to scan the first and second beams of light across a field of regard of the lidar system, and a receiver configured to detect the first beam of light and the second beam of light scattered by one or more remote targets. The scanner includes a rotatable polygon mirror that includes multiple reflective surfaces angularly offset from one another along a periphery of the polygon mirror, the reflective surfaces configured to reflect the first and second beams of light to produce a series of scan lines as the polygon mirror rotates. The scanner also includes a pivotable scan mirror configured to (i) reflect the first and second beams of light and (ii) pivot to distribute the scan lines across the field of regard.

Abstract: A lidar system for scanning a field of regard is described having first and second light beams and first and second detectors. The light beams pass through a lateral beam shifting device prior to being directed to a beam scanner. The lateral beam shifting device reduces the overall size of the emitted and returned light beams thus reducing the size of scanner components. Lateral beam shifting devices may be a single rhomboid prism, a pair of rhomboid prisms, a pair of mirrors, or a single mirror or prism.

Abstract: In one embodiment, a lidar system includes a light source configured to emit multiple optical signals directed into a field of regard of the lidar system. The optical signals include a first optical signal and a second optical signal, where the second optical signal is emitted a particular time interval after the first optical signal is emitted. The lidar system also includes a receiver configured to detect a received optical signal that includes a portion of the emitted first or second optical signal that is scattered by a target located a distance from the lidar system. The received optical signal is detected after the second optical signal is emitted. The receiver includes a first detector configured to detect a first portion of the received optical signal and a second detector configured to detect a second portion of the received optical signal.

Abstract: In one embodiment, a lidar system includes a light source configured to emit pulses of light. The emitted pulses of light include one or more series of standard-resolution pulses alternating with one or more series of high-resolution pulses. Each series of the standard-resolution pulses includes multiple pulses having a standard pulse period, and each series of the high-resolution pulses includes multiple pulses having a high-resolution pulse period. The standard pulse period is greater than or equal to a round-trip time associated with a maximum range of the lidar system, and the high-resolution pulse period is less than the standard pulse period. The lidar system also includes a scanner configured to scan at least a portion of the emitted pulses of light across a field of regard.

Abstract: In one embodiment, a lidar system includes a light source configured to emit (i) local-oscillator light and (ii) pulses of light. The lidar system also includes a receiver configured to detect the local-oscillator light and a received pulse of light, the received pulse of light including a portion of one of the emitted pulses of light scattered by a target located a distance from the lidar system. The receiver includes a detector configured to produce a photocurrent signal corresponding to a coherent mixing of the local-oscillator light and the received pulse of light. The detector includes a first input side and a second input side located opposite the first input side, where the received pulse of light is incident on the first input side of the detector, and the local-oscillator light is incident on the second input side of the detector.

Abstract: In one embodiment, a lidar system includes a light source configured to emit (i) local-oscillator light and (ii) pulses of light, where each emitted pulse of light is coherent with a corresponding portion of the local-oscillator light. The light source includes a seed laser configured to produce seed light and the local-oscillator light. The light source also includes a pulsed optical amplifier configured to amplify temporal portions of the seed light to produce the emitted pulses of light, where each amplified temporal portion of the seed light corresponds to one of the emitted pulses of light. The lidar system also includes a receiver configured to detect the local-oscillator light and a received pulse of light, the received pulse of light including light from one of the emitted pulses of light that is scattered by a target located a distance from the lidar system.

Abstract: A lidar system identifies anomalous optical pulses received by the lidar system. The lidar system includes a light source configured to output a plurality of transmitted pulses of light, each transmitted pulse of light having one or more representative characteristics, a scanner configured to direct the plurality of transmitted pulses of light to a plurality of locations within a field of regard, and a receiver configured to detect a plurality of received pulses of light from the field of regard. The lidar system is configured to identify an anomalous pulse amongst the plurality of received pulses of light based on its having at least one characteristic that does not correspond to the one or more representative characteristics of the plurality of transmitted pulses of light.