Abstract: A single photon avalanche diode (SPAD) has a cathode coupled to a high voltage supply and an anode coupled to a first node. A photodetection circuit includes: a first n-channel transistor having a drain coupled to the first node, a source coupled to ground, and a gate coupled to a third node; a second n-channel transistor having a drain coupled to the first node, a source coupled to ground, and a gate coupled to a second node; and an inverter having an input coupled to the first node and an output coupled to an intermediate node. A current starved inverter has an input coupled to the intermediate node and an output coupled to the second node, a logic gate has inputs coupled to the intermediate node and the second node, and an output coupled to the third node.

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: An imaging sensor includes a pixel array containing photodiodes, the photodiodes being isolated from one another by full thickness deep trench isolations. Row control circuitry controls which rows of the pixel array operate in an imaging mode and which rows of the pixel array operate in an energy harvesting mode, on a row-by-row basis. Switch circuitry selectively connects different groups of photodiodes in rows operating in the energy harvesting mode into forward biased series configurations between a voltage output line and a ground line, or into forward biased parallel configurations between the voltage output line and the ground line. In the forward biased series configurations, the cathode of at least one photodiode of a given group of photodiodes is directly electrically connected to ground.

Abstract: An apparatus comprises an array of vertical-cavity surface-emitting lasers. Each of the vertical-cavity surface-emitting lasers is configured to be a source of light. The apparatus also comprises an optical arrangement configured to receive light from a plurality of the vertical-cavity surface-emitting lasers and to output a plurality of light beams.

Abstract: An embodiment method of measuring ambient light comprises generating, by an ambient light sensor associated with a screen which alternates between first phases in which light is emitted and second phases in which no light is emitted by the screen, a first signal representative of an intensity of light received by the ambient light sensor during the first and second phases; comparing the first signal with a threshold intensity value; and controlling a timing of an ambient light measurement by the light sensor based on the comparison.

Abstract: Disclosed herein is a method of optical pulse emission including three phases. During a first phase, a capacitor is charged from a supply voltage node. During a second phase, a voltage stored on the capacitor is boosted, and then the capacitor is at least partially discharged through a light emitting device. During a third phase, the capacitor is further discharged by bypassing the light emitting device. The third phase may begin prior to an end of the second phase.

Abstract: Described herein is an electronic device, including a pixel and a turn-off circuit. The pixel includes a single photon avalanche diode (SPAD) having a cathode coupled to a high voltage node and an anode selectively coupled to ground through an enable circuit, and a clamp diode having an anode coupled to the anode of the SPAD and a cathode coupled to a turn-off voltage node. The turn-off circuit includes a sense circuit coupled between the turn-off voltage node and ground and configured to generate a feedback voltage, and a regulation circuit configured to sink current from the turn-off voltage node to ground based upon the feedback voltage such that a voltage at the turn-off voltage node maintains generally constant.

Abstract: Disclosed herein is a time of flight sensing module that includes a reflected laser light detector formed on a printed circuit board, and a plurality of laser modules positioned about a periphery of the reflected laser light detector. Each laser module includes an interposer substrate vertically spaced apart from the printed circuit board, at least one laser diode carried by the interposer substrate, and a diffuser spaced apart from the interposer substrate and over the at least one laser diode. A lens may be positioned over the reflected laser light detector, and the plurality of laser modules are positioned about the periphery of the lens.

Abstract: Described herein is an electronic device, including a pixel and a turn-off circuit. The pixel includes a single photon avalanche diode (SPAD) having a cathode coupled to a high voltage node and an anode selectively coupled to ground through an enable circuit, and a clamp diode having an anode coupled to the anode of the SPAD and a cathode coupled to a turn-off voltage node. The turn-off circuit includes a sense circuit coupled between the turn-off voltage node and ground and configured to generate a feedback voltage, and a regulation circuit configured to sink current from the turn-off voltage node to ground based upon the feedback voltage such that a voltage at the turn-off voltage node maintains generally constant.

Abstract: A method includes dividing a field of view into a plurality of zones and sampling the field of view to generate a photon count for each zone of the plurality of zones, identifying a focal sector of the field of view and analyzing each zone to select a final focal object from a first prospective focal object and a second prospective focal object.

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: An imaging sensor includes a pixel array containing photodiodes, the photodiodes being isolated from one another by full thickness deep trench isolations. Row control circuitry controls which rows of the pixel array operate in an imaging mode and which rows of the pixel array operate in an energy harvesting mode, on a row by row basis. Switch circuitry selectively connects different groups of photodiodes in rows operating in the energy harvesting mode into forward biased series configurations between a voltage output line and a ground line, or into forward biased parallel configurations between the voltage output line and the ground line.

Abstract: In an embodiments, a method for operating a time-of-flight (ToF) ranging array includes: illuminating a field-of-view (FoV) of the ToF ranging array with radiation pulses; receiving reflected radiation pulses with a plurality of single photon avalanche diodes (SPADs) in a region of interest (ROI) of the ToF ranging array, the plurality of SPADs arranged in a plurality of SPAD clusters; determining an ambient count of ambient light events generated by SPADs of a first SPAD cluster of the plurality of SPAD clusters; and gating an output of the first SPAD cluster based on the ambient count.

Abstract: A photonic device includes a PCB having an integrated circuit mounted thereon, with a cap mounted to the PCB and carrying a lens positioned over the integrated circuit. The cap is formed by: an outer wall mounted to the PCB, extending upwardly from the PCB, and surrounding a portion of the integrated circuit; a first retention structure extending inwardly from the outer wall and across the integrated circuit, the first retention structure having a hole defined therein; and a second retention structure having a hole defined therein, the second retention structure being affixed within the first retention structure such that the hole in the second retention structure is axially aligned with the hole in the first retention structure. The lens is mechanically constrained within the cap between the first retention structure and the second retention structure.

Abstract: A method for modulating a signal including operating a circuit in a first arrangement during a first operating interval and switching the circuit between the first arrangement and a second arrangement during a first modulation interval to vary a load on the circuit to produce a first amplitude shift keying (ASK) signal. The method further includes detecting a voltage on the circuit crossing a threshold level and operating the circuit in the second arrangement during a second operating interval. The method also includes switching the circuit between the second arrangement and the first arrangement during a second modulation interval to vary the load on the circuit to produce a second ASK signal.

Abstract: A method includes emitting a pattern of transmitted light into a three-dimensional environment from an optical transmitter and receiving reflected light from the pattern of transmitted light at an optical receiver. The method includes identifying light-sensitive pixels of that are stimulated by from the pattern of reflected light and generating an up-sampled matrix with subsections that correspond to light-sensitive pixels. The method includes sparsely populating subsections of the up-sampled matrix with a pattern of non-zero entries and imaging the three-dimensional environment.

Abstract: Various embodiments provide optical lenses that include phase shift layers that transmit incident light with four or more distinct phase quantizations. In one embodiment, a lens includes a substrate, a first immersion material layer on the substrate, and a plurality of anti-reflective phase shift layers on the first immersion material layer. The phase shift layers define a first anti-reflective phase shift region that transmits received light without a phase shift, a second anti-reflective phase shift region configured to transmit the received light with a first phase shift, a third anti-reflective phase shift region configured to transmit the received light with a second phase shift, and a fourth anti-reflective phase shift region configured to transmit the received light with a third phase shift. The first, second, and third phase shifts are different from one another.

Abstract: A lens is positioned to be received by a lens holder. The lens includes a first electrical trace and the lens holder includes a second electrical trace. The first and second electrical traces form electrodes of a sense capacitor. A capacitance of the sense capacitor is sensed. From the sensed capacitance, a determination is made as to whether the lens is present and properly positioned in the lens holder.

Abstract: A ToF sensor includes an array of pixels having first and second subsets of pixels, first and second pluralities of TDCs, a routing bus having first and second pluralities of bus drivers, and a controller configured to: when the first subset of pixels is active and the second subset of pixels is not active, control the first plurality of bus drivers to route events from half of the pixels of the first subset to the first plurality of TDCs and control the first and second pluralities of bus drivers to route events from the other half of the pixels of the first subset to the second plurality of TDCs, and when the first subset of pixels is not active and the second subset of pixels is active, control the first plurality of bus drivers to route events from the second subset of pixels to the first plurality of TDCs.

Abstract: Disclosed herein is an array of pixels. Each pixel includes a single photon avalanche diode (SPAD) and a transistor circuit. The transistor circuit includes a clamp transistor configured to clamp an anode voltage of the SPAD to be no more than a threshold clamped anode voltage, and a quenching element in series with the clamp transistor and configured to quench the anode voltage of the SPAD when the SPAD is struck by an incoming photon. Readout circuitry is coupled to receive the clamped anode voltage from the transistor circuit and to generate a pixel output therefrom, the threshold clamped anode voltage being below a maximum voltage rating of transistors forming the readout circuitry.