Abstract: A distance from an apparatus to at least one object is determined by generating a first signal and generating light modulated by the first signal to be emitted from the apparatus. Light reflected by the at least one object is detected using a Time-of-flight detector array, wherein each array element of the Time-of-flight detector array generates an output signal from a series of photon counts over a number of consecutive non-overlapping time periods. The output signals are compared to the first signal to determine at least one signal phase difference. From this at least one signal phase difference a distance from the apparatus to the at least one object is determined.

Abstract: An electronic device includes laser emitters, and a laser driver generating a laser drive signal for the laser emitters based upon a feedback control signal. A steering circuit selectively steers the laser drive signal to a different selected one of the plurality of laser emitters and prevents the laser drive signal from being steered to non-selected ones of the plurality of laser emitters, during each of a plurality of time periods. Control circuitry senses a magnitude of a current of the laser drive signal and generates the feedback control signal based thereupon. The feedback control signal is generated so as to cause the laser driver to generate the laser drive signal as having a current with a substantially constant magnitude.

Abstract: A ranging system includes a first ranging unit with a first laser driver, a first control circuit generating a first trigger signal, and a first data interface with a first trigger transmitter transmitting the first trigger signal over a first data transmission line and a first calibration receiver receiving a first calibration signal over a second data transmission line. A second ranging unit includes a second laser driver, a second data interface with a second trigger receiver receiving the first trigger signal and a second calibration transmitter transmitting the first calibration signal, and a second control circuit generating the first calibration signal in response to receipt of the first trigger signal. The first control circuit determines an elapsed time between transmission of the first trigger signal and receipt of the first calibration signal. The determined elapsed time is used to synchronize activation of the first and second laser drivers.

Abstract: The present disclosure is directed to a diode including a first doped structure, doped with a first type of material and forming at least part of an isolation structure for the diode; at least one contact structure located within the first doped structure, the at least one contact structure forming one of the cathode or anode of the diode; a second doped structure, doped with a second type of material, and forming at least one depletion region or PN junction with the first doped structure; at least one second contact structure located within the second doped structure, the at least one second contact structure forming the other of the anode or the cathode of the diode; at least one further contact structure, doped with the first type of material, the at least one further contact structure forming at least one further depletion region or further PN junction, such that the at least one further depletion region is configured to steer charge from the at least one depletion region and thus decrease the sensitivity

Abstract: In an embodiment, a TDC includes: a clock input configured to receive a reference clock that is synchronized with a first event; a clock generation circuit configured to generate a first clock at a first output of the clock generation circuit based on the reference clock, the first clock having a second frequency lower than the reference clock; a data input configured to receive an input stream of pulses, where the input stream of pulses is based on the first event; a sampling circuit having an input register, the sampling circuit coupled to the data input, the sampling circuit configured to continuously sample the input stream of pulses into the input register based on the reference clock; and output terminals configured to stream time stamps based on the input stream of pulses at the second frequency, where the stream of time stamps is synchronized with the first clock.

Abstract: In an embodiment of the present invention, a method for controlling a voltage across a single photon avalanche diode includes: providing an output based on a current flowing through the single photon avalanche diode; and controlling the voltage applied across the single photon avalanche diode based on the provided output.

Abstract: An apparatus includes a single photon avalanche diode pixel that includes a single photon avalanche diode and an output transistor configured to provide an analog output current from the single photon avalanche diode. The single photon avalanche diode pixel is configured to operate in a first mode to output a digital single photon detection event. The single photon avalanche diode pixel is further configured to operate in a second mode to output the analog output current indicating a level of illumination of the pixel.

Abstract: In one embodiment, an imaging device includes a light-emitting device, a driving circuit, a return single-photon avalanche diode (SPAD) array and readout circuitry. The driving circuit generates a driving signal, and the light-emitting device generates an optical pulse based on the driving signal. The return SPAD array is configured to receive a first portion of the optical pulse that is reflected by an object in an image scene. The readout circuitry receives a signal indicative of the received first portion of the optical pulse, and a signal indicative of the driving signal, and determines a distance between the imaging device and the object based on a difference between a time of receiving the signal indicative of the received first portion of the optical pulse and a time of receiving the signal indicative of the driving signal.

Abstract: An apparatus can be used for detecting pile-up within circuitry associated with photodetectors. The apparatus includes an input terminal configured to receive a plurality of photodetector outputs. An OR-tree is coupled in parallel with the circuitry associated with the photodetectors. The OR-tree has an input coupled to the input terminal and is configured to combine the photodetector outputs. A counter is configured to count an output of the OR-tree. A comparator is configured to compare an output of the counter to a determined threshold value, wherein the comparator is configured to output an indicator indicating pile-up within the circuitry associated with photodetectors based on the output of the counter being greater than or equal to the determined threshold value.

Abstract: One or more embodiments are directed to charge pump overload detection circuits which may be employed in imaging devices including one or more SPAD arrays, such as proximity sensors and time of flight sensors. One embodiment is directed to a charge pump overload detection circuit that includes a charge pump, a charge pump supply regulation device, a charge pump voltage regulation feedback loop and a charge pump overload detection comparator. The charge pump supplies an output voltage to a load, and the charge pump supply regulation device supplies a regulated voltage to an input of the charge pump. The charge pump voltage regulation feedback loop includes a feedback voltage generator that generates a feedback voltage based on the charge pump output voltage, and an amplifier that generates and provides a charge pump regulation control signal to the charge pump supply regulation device based on a difference between the feedback voltage and a reference voltage.

Abstract: An optical sensor includes at least one photodetector configured to be reverse biased at a voltage exceeding a breakdown voltage by an excess bias voltage. At least one control unit is configured to adjust the reverse bias of the at least one photodetector. A method of operating an optical sensor is also disclosed.

Abstract: A ranging apparatus includes an array of light sensitive detectors configured to receive light from a light source which has been reflected by an object. The array includes a number of different zones. Readout circuitry including at least one read out channel is configured to read data output from each of the zones. A processor operates to process the data output to determine position information associated with the object.

Abstract: In one embodiment, an imaging device includes a light-emitting device, a driving circuit, a return single-photon avalanche diode (SPAD) array and readout circuitry. The driving circuit generates a driving signal, and the light-emitting device generates an optical pulse based on the driving signal. The return SPAD array is configured to receive a first portion of the optical pulse that is reflected by an object in an image scene. The readout circuitry receives a signal indicative of the received first portion of the optical pulse, and a signal indicative of the driving signal, and determines a distance between the imaging device and the object based on a difference between a time of receiving the signal indicative of the received first portion of the optical pulse and a time of receiving the signal indicative of the driving signal.

Abstract: A distance sensing apparatus includes a light source configured to emit polarized light. A light sensitive detector detects light emitted by said light source and reflected from a target. The light sensitive detector is configured to substantially prevent polarized light reflected from a target with a relatively high reflectance from being detected.

Abstract: In an embodiment, a TDC includes: a clock input configured to receive a reference clock that is synchronized with a first event; a clock generation circuit configured to generate a first clock at a first output of the clock generation circuit based on the reference clock, the first clock having a second frequency lower than the reference clock; a data input configured to receive an input stream of pulses, where the input stream of pulses is based on the first event; a sampling circuit having an input register, the sampling circuit coupled to the data input, the sampling circuit configured to continuously sample the input stream of pulses into the input register based on the reference clock; and output terminals configured to stream time stamps based on the input stream of pulses at the second frequency, where the stream of time stamps is synchronized with the first clock.

Abstract: An apparatus includes an illumination source configured to emit light when driven with a current greater than a threshold current and driver circuitry configured to drive the illumination source with a controllable current. The driver circuit controlled by at least a first input value. At least one illumination detector is configured to detect light emitted by the illumination source and monitor circuitry is configured to receive an output from the illumination detector and provide the first input value.

Abstract: An embodiment circuit includes a diode having a first terminal coupled to a first reference voltage; a first controllable switch coupled between a second terminal of the diode and a second reference voltage; and a capacitive element having a first terminal coupled to the first reference voltage and a second terminal controllably coupled to the second terminal of the diode.

Abstract: The present disclosure includes a method that includes generating a decoded output signal that corresponds to reflected light received by a plurality of single photon avalanche diodes (SPAD) by removing ambient light from a plurality of SPAD array output signals. The removing of ambient light including synchronizing the plurality of SPAD array output signals by using a plurality of parallel time to digital converters, each time to digital converter outputting a synchronized SPAD array output signal, determining a plurality of flexible thresholds for each one of the synchronized SPAD array output signals, comparing current data on the synchronized SPAD array output signals with the respective ones of the flexible threshold in a filter, and outputting the first output signal.

Abstract: Photoluminescence from a sample detector is detected using an array of photo-sensitive detectors. At least one first photo-sensitive detector of the array is provided with a first type of linear polarization filter and at least one second photo-sensitive detector is provided with a second type of linear polarization filter. The first type of linear polarization filter has a plane of polarization which is at angled with respect to a plane of polarization of said second type of polarization filter.

Abstract: An embodiment circuit includes a diode having a first terminal coupled to a first reference voltage; a first controllable switch coupled between a second terminal of the diode and a second reference voltage; and a capacitive element having a first terminal coupled to the first reference voltage and a second terminal controllably coupled to the second terminal of the diode.