Patent classifications
G01S7/4876
READOUT CIRCUIT AND METHOD FOR TIME-OF-FLIGHT IMAGE SENSOR
A time-of-flight device comprises a pixel array including an array of pixel circuits, wherein a column of the array includes: a first pixel circuit including a first photodiode, a first capacitor and a second capacitor coupled to the first photodiode, and a second pixel circuit including a second photodiode, a third capacitor and a fourth capacitor coupled to the second photodiode, a first signal line coupled to the first capacitor, a second signal line coupled to the second capacitor, a third signal line coupled to the third capacitor, a fourth signal line coupled to the fourth capacitor, a first switch circuitry, a second switch circuitry, a first comparator coupled to the first signal line and the third signal line through the first switch circuitry, and a second comparator coupled to the second signal line and the fourth signal line through the second switch circuitry.
LIDAR data acquisition and control
Methods and systems for performing three dimensional LIDAR measurements with an integrated LIDAR measurement device are described herein. In one aspect, a return signal receiver generates a pulse trigger signal that triggers the generation of a pulse of illumination light and data acquisition of a return signal, and also triggers the time of flight calculation by time to digital conversion. In addition, the return signal receiver also estimates the width and peak amplitude of each return pulse, and samples each return pulse waveform individually over a sampling window that includes the peak amplitude of each return pulse waveform. In a further aspect, the time of flight associated with each return pulse is estimated based on a coarse timing estimate and a fine timing estimate. In another aspect, the time of flight is measured from the measured pulse due to internal optical crosstalk and a valid return pulse.
TIME-OF-FLIGHT IMAGING CIRCUITRY, TIME-OF-FLIGHT IMAGING SYSTEM, AND TIME-OF-FLIGHT IMAGING METHOD
The present disclosure generally pertains to time-of-flight imaging circuitry configured to: control a set of readout channels for an imaging element for obtaining a set of events representing a set of light pulses captured in the imaging element, wherein the controlling includes: a first detection of the set of events in a first readout channel of the set of readout channels; and a second detection in a second readout channel, wherein the second detection starts a predetermined time after a start of the first detection for detecting a subset of the events.
A SENSING SYSTEM
A sensing system comprising an emitter configured to emit electromagnetic radiation, a detector configured to detect electromagnetic radiation and an electronic component configured to interact with a circuitry of the sensing system. The electronic component is located at least partially between the emitter and the detector. The electronic component reduces an amount of electromagnetic radiation propagating from the emitter to the detector. The electronic component advantageously reduces the unwanted detection of electromagnetic radiation that would otherwise propagate directly from the emitter to the detector without leaving the sensing system, thereby reducing a measurement noise and improving an accuracy of the sensing system. The sensing system may form part of a time-of-flight sensing system or a proximity sensing system. The sensing system may form part of an electronic device such as a mobile phone.
LIGHT WAVE DISTANCE METER
The light wave distance meter is disclosed, including: a distance measuring light-emitting unit; a light-receiving signal generating unit; and a control arithmetic unit. A light-receiving signal includes a first intermittent light-receiving signal corresponding to a first distance measuring light, a second intermittent light-receiving signal corresponding to a second distance measuring light, a third intermittent light-receiving signal corresponding to a third distance measuring light, and a fourth intermittent light-receiving signal corresponding to a fourth distance measuring light. The control arithmetic unit executes an error determination control to acquire a shift signal generated by shifting at least a phase of any one of the first to fourth intermittent light-receiving signals by 2π.Math.n−π/2 or 2π.Math.n+π/2, and compares the phase of the shift signal and the phase of the intermittent light-receiving signal at least between either the first frequencies or between the second frequencies.
ADDRESSING REDUNDANT MEMORY FOR LIDAR PIXELS
Techniques described herein provide memory redundancy. For example, the memory block for each pixel can be partitioned into multiple memory bins, and the number of memory bins can be larger than the number of time bins. Once a faulty memory cell is identified, an address associated with the memory bin that has the faulty memory cell can be skipped by an address generator. As such, the faulty memory cell is not used to store time-of-fight (ToF) information.
PROJECTOR WITH SPATIAL LIGHT MODULATION
A time of flight based depth detection system is disclosed that includes a projector configured to sequentially emit multiple complementary illumination patterns. A sensor of the depth detection system is configured to capture the light from the illumination patterns reflecting off objects within the sensor's field of view. The data captured by the sensor can be used to filter out erroneous readings caused by light reflecting off multiple surfaces prior to returning to the sensor.
INTERFERENCE POINT DETERMINING METHOD AND APPARATUS, STORAGE MEDIUM, AND MULTI-CHANNEL LIDAR
An interference point determining method is provided. The method includes: obtaining a target point cloud corresponding to a highly reflective object from a target channel; obtaining a to-be-determined point cloud at the same pixel position as the target point cloud from each channel other than the target channel based on the target point cloud; based on a distance value and a reflectivity of each to-be-determined point cloud, and distance values and reflectivities respectively corresponding, to other point clouds in a neighborhood of each to-be-determined point cloud, determining whether each to-be-determined point cloud is a suspected interference point; and based on a variance between distance values of the other point clouds in the neighborhood of one to-be-determined point cloud and the one to-be-determined point cloud, or based on an interference point range determined for the one to-be-determined point cloud, determining whether the one to-be-determined point cloud is the interference point.
LIDAR SYSTEMS WITH REDUCED INTER-CHIP DATA RATE
A light detection and ranging (LiDAR) system may include a laser and a array of single photon avalanche diodes (SPADs) that are triggered by laser light that reflects off a target scene. The LiDAR system may use the array of SPADs to assemble a raw histogram data. A histogram valid peak detector can be used to filter the raw histogram data to extract only valid histogram peak signals exceeding a threshold value. The histogram valid peak detector may include a raw histogram sum counter, a non-zero bins counter, a background noise floor generator, summing circuits, comparators, and a gating circuit, all controlled by a sequencing circuit. By filtering out noise signals in the raw histogram while only transferring the valid peak signals, data transfer rate requirements between different chips in the overall LiDAR system can be dramatically reduced.
MULTI-SENSOR LIDAR
A light detection and ranging system can have a camera sensor connected to an optical sensor and a controller with the optical sensor consisting of a light source coupled to a emitter and a detector for identifying downrange targets with photons. The camera sensor consisting of a lens for capturing a downrange image. The controller can track downrange targets with the camera sensor at a different frame rate than the optical sensor.