Abstract: A lidar system includes a light source, a scanner, and a receiver and is configured to detect remote targets located up to RMAX meters away. The receiver includes a detector with a field of view larger than the light-source field of view. The scanner causes the detector field of view to move relative to the instantaneous light-source field of view along the scan direction, so that (i) when a pulse of light is emitted, the instantaneous light-source field of view is approximately centered within the detector field of view, and (ii) when a scattered pulse of light returns from a target located RMAX meters away, the instantaneous light-source field of view is located near an edge of the field of view of the detector and is contained within the field of view of the detector.

Abstract: To decrease the likelihood of a false detection when detecting light from light pulses scattered by remote targets in a lidar system, a receiver in the lidar system includes a photodetector and a pulse-detection circuit having a gain circuit with a varying amount of gain over time. The gain circuit operates in a low-gain mode for a time period T1 beginning with time t0 when a light pulse is emitted to prevent the receiver from detecting return light pulses during the threshold time period T1. Upon expiration of the threshold time period T1, the gain circuit operates in a high-gain mode to begin detecting return light pulses until a subsequent light pulse is emitted.

Abstract: A lidar system comprises a light source configured to emit light, a scanner configured to direct the emitted light to scan a field of regard of the lidar system in accordance with a scan pattern, a receiver configured to detect the light scattered by one or more remote targets, and a controller configured to control motion of at least the second mirror to modify the scan pattern. The scanner includes a rotatable polygon mirror having a block having a first wall, a second wall, and reflective surfaces extending between the first and second walls, the reflective surfaces being angularly offset from one another along a periphery of the block. The scanner also includes a polygon mirror axle extending into the block through at least one of the first and second walls, about which the block rotates, and a second mirror pivotable along an axis orthogonal to the polygon mirror axle.

Abstract: In one embodiment, a lidar system includes a light source configured to emit pulses of light and a scanner configured to scan at least a portion of the emitted pulses of light across a field of regard. The lidar system also includes a receiver configured to detect at least a portion of the scanned pulses of light scattered by a target located a distance from the lidar system.

Abstract: A lidar system with improved signal-to-noise ratio in the presence of solar background noise. The lidar system can comprise a light source to emit light toward a target. The light source can have an operating wavelength which lies within a band that delineates a relative maximum in atmospheric absorption. The lidar system can also include a detector to detect scattered light from the target and a processor to determine a characteristic of the target based on a characteristic of the scattered light received at the detector.

Abstract: A lidar system includes a transmitter that encodes successive transmit pulses with different pulse characteristics and a receiver that detects the pulse characteristics of each received (scattered or reflected) pulse and that distinguishes between the received pulses based on the detected pulse characteristics. The lidar system thus resolves range ambiguities by encoding pulses of scan positions in the same or different scan periods to have different pulse characteristics, such as different pulse widths or different pulse envelope shapes. The receiver includes a pulse decoder configured to detect the relevant pulse characteristics of the received pulse and a resolver that determines if the pulse characteristics of the received pulse matches the pulse characteristics of the current scan position or that of a previous scan position.

Abstract: A lidar system can include a light source that emits a pulse of light and a splitter that splits the pulse of light into two or more pulses of angularly separated light. The lidar system can also include a scanner configured to scan pulses of light along a scanning direction across a plurality of pixels located downrange from the lidar system. The lidar system can also include a detector array with a first detector and a second detector. The first and second detectors can be separated by a detector-separation distance along a direction corresponding to the scanning direction of the light pulses. The first detector can be configured to detect scattered light from the first pulse of light and the second detector can be configured to detect scattered light from the second pulse of light.

Abstract: A lidar system can include a solid-state laser to emit pulses of light. The solid-state laser can include a Q-switched laser having a gain medium and a Q-switch. The lidar system can also include a scanner configured to scan the emitted pulses of light across a field of regard and a receiver configured to detect at least a portion of the scanned pulses of light scattered by a target located a distance from the lidar system. The lidar system can also include a processor configured to determine the distance from the lidar system to the target based at least in part on a round-trip time of flight for an emitted pulse of light to travel from the lidar system to the target and back to the lidar system.

Abstract: A lidar system includes a light source configured to emit light, a scanner configured to scan a field of regard of the lidar system using (i) a first output beam that includes at least a portion of the emitted light and has a first amount of power and (ii) a second output beam that includes at least a portion of the emitted light and has a second amount of power different from the first amount of power, with an angular separation between the first output beam and the second output beam along a vertical dimension of the field of regard, and a receiver configured to detect light associated with the first output beam and light associated with the second output beam scattered by one or more remote targets.

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: To compensate for the uneven distribution of data points around the periphery of a vehicle in a lidar system, a light source transmits light pulses at a variable pulse rate according to the orientation of the light pulses with respect to the lidar system. A controller may communicate with a scanner in the lidar system that provides the orientations of the light pulses to the controller. The controller may then provide a control signal to the light source adjusting the pulse rate based on the orientations of the light pulses. For example, the pulse rate may be slower near the front of the lidar system and faster near the periphery. In another example, the pulse rate may be faster near the front of the lidar system and slower near the periphery.

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: A lidar system can include a solid-state laser to emit pulses of light. The solid-state laser can include a Q-switched laser having a gain medium and a Q-switch. The lidar system can also include a scanner configured to scan the emitted pulses of light across a field of regard and a receiver configured to detect at least a portion of the scanned pulses of light scattered by a target located a distance from the lidar system. The lidar system can also include a processor configured to determine the distance from the lidar system to the target based at least in part on a round-trip time of flight for an emitted pulse of light to travel from the lidar system to the target and back to the lidar system.

Abstract: In one embodiment, a lidar system includes a light source configured to emit a ranging pulse of light that is directed into a field of regard of the lidar system. The lidar system also includes a fiber-optic splitter configured to split off a portion of the ranging pulse of light to produce a trigger pulse of light that is directed to a receiver of the lidar system. The receiver is configured to detect, at a first time, at least a portion of the trigger pulse of light; and detect, at a second time subsequent to the first time, a portion of the ranging pulse of light scattered by a target located a distance from the lidar system. The lidar system further includes a processor configured to determine the distance from the lidar system to the target based at least in part on the first time and the second time.

Abstract: An optical scanner includes a rotatable polygon mirror and a second mirror. The rotatable polygon mirrors includes a block having a first wall, a second wall, and reflective surfaces extending between the first and second walls, the reflective surfaces being angularly offset from one another along a periphery of the block; a polygon mirror axle extending into the block through at least one of the first and second walls, about which the block rotates; a motor driving rotation of the block; and chamfers in the block, each of the chamfers being bounded by a pair of adjacent reflective surfaces and the second wall. The second mirror is pivotable along an axis orthogonal to the polygon mirror axle and more proximate to the second wall of the block than the first wall of the block.

Abstract: A lidar system includes one or more light sources configured to generate a first and second beams of light, a scanner configured to synchronously scan a field of regard of the lidar system using the two beams, and a receiver configured to detect light of the two beams scattered by one or more remote targets. The scanner includes a rotatable polygon mirror having a block having a first wall, a second wall, and reflective surfaces extending between the first and second walls, the reflective surfaces being angularly offset from one another along a periphery of the block; a polygon mirror axle extending into the block, about which the block rotates; optical elements configured to direct the first and second beams of light respectively to two adjacent reflective surfaces of the rotatable polygon mirror; and a second mirror pivotable along an axis orthogonal to the polygon mirror axle.

Abstract: An optical scanner includes a rotatable polygon mirror and a second mirror. The rotatable polygon mirrors includes a block having a first wall, a second wall, and reflective surfaces extending between the first and second walls, the reflective surfaces being angularly offset from one another along a periphery of the block; a polygon mirror axle extending into the block through at least one of the first and second walls, about which the block rotates; a motor driving rotation of the block; and chamfers in the block, each of the chamfers being bounded by a pair of adjacent reflective surfaces and the second wall. The second mirror is pivotable along an axis orthogonal to the polygon mirror axle and more proximate to the second wall of the block than the first wall of the block.

Abstract: A lidar system includes one or more light sources configured to generate a first and second beams of light, a scanner configured to synchronously scan a field of regard of the lidar system using the two beams, and a receiver configured to detect light of the two beams scattered by one or more remote targets. The scanner includes a rotatable polygon mirror having a block having a first wall, a second wall, and reflective surfaces extending between the first and second walls, the reflective surfaces being angularly offset from one another along a periphery of the block; a polygon mirror axle extending into the block, about which the block rotates; optical elements configured to direct the first and second beams of light respectively to two adjacent reflective surfaces of the rotatable polygon mirror; and a second mirror pivotable along an axis orthogonal to the polygon mirror axle.

Abstract: A lidar system comprises a light source configured to emit light, a scanner configured to direct the emitted light to scan a field of regard of the lidar system in accordance with a scan pattern, a receiver configured to detect the light scattered by one or more remote targets, and a controller configured to control motion of at least the second mirror to modify the scan pattern. The scanner includes a rotatable polygon mirror having a block having a first wall, a second wall, and reflective surfaces extending between the first and second walls, the reflective surfaces being angularly offset from one another along a periphery of the block. The scanner also includes a polygon mirror axle extending into the block through at least one of the first and second walls, about which the block rotates, and a second mirror pivotable along an axis orthogonal to the polygon mirror axle.

Abstract: A lidar system is disclosed. The lidar system can include a light source to produce first and second sets of pulses of light. The system can also include a first lidar sensor with a first scanner to scan the first set of pulses of light along a first scan pattern, and a first receiver to detect scattered light from the first set of pulses of light. The system can also include a second lidar sensor with a second scanner to scan the second set of pulses of light along a second scan pattern, and a second receiver to detect scattered light from the second set of pulses of light. The first scan pattern and the second scan pattern can be at least partially overlapped in an overlap region. The lidar system can also include an enclosure to contain the light source, the first lidar sensor, and the second lidar sensor.