Abstract: A depth map sensor includes a first array of first pixels, each first pixel having a first photodetector associated with a pixel circuit that comprises a plurality of first bins for accumulating events. A clock source is configured to generate a plurality of phase-shifted clock signals. A first circuit has a plurality of first output lines coupled to the first array of first pixels. The first circuit is configured to receive the plurality of phase-shifted clock signals. The first circuit includes a first block and a second block. The first block is configured to propagate the plurality of phase-shifted clock signals to the second block during a first period determined by a first enable signal and the second block configured to select to which of the plurality of first output lines each of the plurality of phase-shifted clock signals is applied.

Abstract: A time-of-flight (TOF) imaging system includes illumination circuitry, such as a laser, one or more sensors, such as SPAD arrays, and image processing circuitry. The illumination circuitry illuminates one or more objects in an environment around the TOF imaging system. The sensors generate an image data stream based on reflections from the one or more illuminated objects, and possibly based on reflections from one or more reflectors. The image processing circuitry generates counts associated with distances based on the image data stream and possibly a reflection data stream and stores the generated counts in a histogram using a plurality of bins. Each of the plurality of bins stores counts associated with a respective distance range. A size of a bin in the plurality of bins is a function of the respective distance range, and may be based on a logarithmic function of the distance associated with the bin.

Abstract: A method of processing a visible light communication (VLC) signal using a single-photon avalanche diode (SPAD) includes detecting photons of a VLC signal at a SPAD detector, counting the photons detected by the SPAD detector to generate a combined VLC signal comprising a data signal and an ambient signal, extracting the ambient signal from the combined VLC signal, subtracting the ambient signal from the combined VLC signal to generate the data signal, and outputting the data signal as a bitstream.

Abstract: A time-of-flight ranging system disclosed herein includes a receiver asserting a photon received signal in response to detection of light that has reflected off a target and returned to the time-of-flight ranging system. A first latch circuit has first and second data inputs receiving a first pair of differential timing references, the first latch circuit latching data values at its first and second data inputs to first and second data outputs based upon assertion of the photon received signal. A first counter counts latching events of the first latch circuit during which the first data output is asserted, and a second counter counts latching events of the first latch circuit during which the second data output is asserted. Processing circuitry determines distance to the target based upon counted latching events output from the first and second counters.

Abstract: A method of processing a visible light communication (VLC) signal using a single-photon avalanche diode (SPAD) includes detecting photons of a VLC signal at a SPAD detector, counting the photons detected by the SPAD detector to generate a combined VLC signal comprising a data signal and an ambient signal, extracting the ambient signal from the combined VLC signal, subtracting the ambient signal from the combined VLC signal to generate the data signal, and outputting the data signal as a bitstream.

Abstract: In an embodiment, a method includes: providing a gray-coded time reference to a time-to-digital converter (TDC); receiving an event from an event signal; latching the gray-coded time reference into a memory upon reception of the event signal; and updating a time-of-flight (ToF) histogram based on the latched gray-coded time reference.

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 embodiment method of operating an imaging device including a sensor array including a plurality of pixels, includes: capturing a first low-spatial resolution frame using a subset of the plurality of pixels of the sensor array; generating, using a processor coupled to the sensor array, a first depth map using raw pixel values of the first low-spatial resolution frame; capturing a second low-spatial resolution frame using the subset of the plurality of pixels of the sensor array; generating, using the processor, a second depth map using raw pixel values of the second low-spatial resolution frame; and determining whether an object has moved in a field of view of the imaging device based on a comparison of the first depth map to the second depth map.

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: A combining network for an array of SPAD devices includes: synchronous sampling circuits, wherein each synchronous sampling circuit is coupled to an output of a corresponding SPAD device and is configured to generate a pulse or an edge each time an event is detected; and a summation circuit coupled to an output of each of the synchronous sampling circuits and configured to count a number of pulses or edges to generate a binary output value.

Abstract: In some embodiments, a ToF sensor includes an illumination source module, a transmitter lens module, a receiver lens module, and an integrated circuit that includes a ToF imaging array. The ToF imaging array includes a plurality of SPADs and a plurality of ToF channels coupled to the plurality of SPADs. In a first mode, the ToF imaging array is configured to select a first group of SPADs corresponding to a first FoV. In a second mode, the ToF imaging array is configured to select a second group of SPADs corresponding to a second FoV different than the first FoV.

Abstract: An embodiment method of operating an imaging device including a sensor array including a plurality of pixels, includes: capturing a first low-spatial resolution frame using a subset of the plurality of pixels of the sensor array; generating, using a processor coupled to the sensor array, a first depth map using raw pixel values of the first low-spatial resolution frame; capturing a second low-spatial resolution frame using the subset of the plurality of pixels of the sensor array; generating, using the processor, a second depth map using raw pixel values of the second low-spatial resolution frame; and determining whether an object has moved in a field of view of the imaging device based on a comparison of the first depth map to the second depth map.

Abstract: In some embodiments, a ToF sensor includes an illumination source module, a transmitter lens module, a receiver lens module, and an integrated circuit that includes a ToF imaging array. The ToF imaging array includes a plurality of SPADs and a plurality of ToF channels coupled to the plurality of SPADs. In a first mode, the ToF imaging array is configured to select a first group of SPADs corresponding to a first FoV. In a second mode, the ToF imaging array is configured to select a second group of SPADs corresponding to a second FoV different than the first FoV.

Abstract: A sensor has plurality of pixels arranged in a plurality of rows and columns with row control circuitry for controlling which one of said rows is activated and column control circuitry for controlling which of said pixels in said activated row is to be activated. The column circuitry has memory configured to store information indication as to which of the pixels are defective, wherein each of the pixels has a photodiode and a plurality of transistors which control the activation of the photodiode. A first transistor is configured to be controlled by a column enable signal while a second transistor is configured to be controlled by a row select signal.

Abstract: A laser diode driver circuit includes a first pair of contacts and connectors coupled to an anode of the laser diode. An inductance of each of the first pair of contacts and connectors is the same. A second pair of contacts and connectors are coupled to a cathode of the laser diode. An inductance of each of the second pair of contacts and connectors is the same. The laser diode driver circuit also includes current driving circuitry.

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: A method can be used for controlling pixel scanning within a range detector. A spatially controllable point light source generates a first series of light source pulses associated with a first spatial direction. The first series of light source pulses are generated during a first time period. The spatially controllable point light source generates a second series of light source pulses associated with a second spatial direction. The second series of light source pulses are generated during a second time period that overlaps with the first time period so that the second series of light source pulses are started during the first series of light source pulses.

Abstract: SPADs detect photons of a return light pulse and output corresponding pulse signals. First and second counters, when enabled in response to phase measurement value, are configured to count the pulse signals. The phase measurement value is set for a subsequent iteration of the return light pulse in response to processing of first and second count values of the first and second counters, respectively, for a current iteration. If the first count value exceeds the second count value by more than a difference threshold limit, the phase measurement value is decremented for the subsequent iteration. Otherwise, the phase measurement value is incremented for the subsequent iteration. If the difference threshold limit is not satisfied, the phase measurement value may be maintained for the subsequent iteration, but one of the counters is preloaded for the subsequent iteration with a value equal to a magnitude of the difference between the count values.

Abstract: An embodiment method of operating an imaging device including a sensor array including a plurality of pixels, includes: capturing a first low-spatial resolution frame using a subset of the plurality of pixels of the sensor array; generating, using a processor coupled to the sensor array, a first depth map using raw pixel values of the first low-spatial resolution frame; capturing a second low-spatial resolution frame using the subset of the plurality of pixels of the sensor array; generating, using the processor, a second depth map using raw pixel values of the second low-spatial resolution frame; and determining whether an object has moved in a field of view of the imaging device based on a comparison of the first depth map to the second depth map.

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.