An electronic device may include a proximity sensor for detecting whether an external object is in the vicinity of the device. The proximity sensor may have a light detector and a light source that can be reused for data communications. The light detector may be coupled to optical receiver circuitry, whereas the light source may be coupled to optical transmitter circuitry. The optical transmitter circuitry may include encoding circuits configured to convert electrical signals to optical signals. The optical receiver circuitry may include decoding circuits configured to convert optical signals to electrical signals. The optical signals can be encoded and decoded using pulse width modulation schemes or amplitude modulation schemes.

An electronic device may include a proximity sensor for detecting whether an external object is in the vicinity of the device. The proximity sensor may have a light detector and a light source that can be reused for data communications. The light detector may be coupled to optical receiver circuitry, whereas the light source may be coupled to optical transmitter circuitry. The optical transmitter circuitry may include encoding circuits configured to convert electrical signals to optical signals. The optical receiver circuitry may include decoding circuits configured to convert optical signals to electrical signals. The optical signals can be encoded and decoded using pulse width modulation schemes or amplitude modulation schemes.

Apparatus and method for adaptively adjusting amplifier gain based on detected distance to a target in a light detection and ranging (LiDAR) system. In some embodiments, the amplifier amplifies detected pulses obtained from a photodetector, and the gain is adjusted from among at least two selectable gain modes responsive to a measured time of flight (ToF) for the pulses. A first range of gain levels can be used for targets that are within a first maximum distance range, and a second range of gain levels can be used for targets that are beyond the first maximum distance range. Each mode can extend from a minimum to a maximum value along a selected linear slope. A gain adjustment circuit can use a Gilbert Cell or a multiplier and fully differential amplifier arrangement.

Apparatus and method for adaptively adjusting amplifier gain based on detected distance to a target in a light detection and ranging (LiDAR) system. In some embodiments, the amplifier amplifies detected pulses obtained from a photodetector, and the gain is adjusted from among at least two selectable gain modes responsive to a measured time of flight (ToF) for the pulses. A first range of gain levels can be used for targets that are within a first maximum distance range, and a second range of gain levels can be used for targets that are beyond the first maximum distance range. Each mode can extend from a minimum to a maximum value along a selected linear slope. A gain adjustment circuit can use a Gilbert Cell or a multiplier and fully differential amplifier arrangement.

Method and apparatus for enhancing resolution in a light detection and ranging (LiDAR) system. In some embodiments, an emitter is used to emit light pulses at a first resolution within a baseline, first field of view (FoV). A specially configured optical element, such as a refractive optical lens, is activated responsive to an input signal to direct at least a portion of the emitted light pulses to an area of interest characterized as a second FoV within the first FoV. The second FoV is provided with a higher, second resolution. In some cases, all of the light pulses are directed through the optical element to the second FoV. In other cases, the first FoV continues to be scanned at a reduced resolution. A rotatable polygon, micromirrors and/or solid state array mechanisms can be used to divert the pulses to the optical element.

Method and apparatus for enhancing resolution in a light detection and ranging (LiDAR) system. In some embodiments, an emitter is used to emit light pulses at a first resolution within a baseline, first field of view (FoV). A specially configured optical element, such as a refractive optical lens, is activated responsive to an input signal to direct at least a portion of the emitted light pulses to an area of interest characterized as a second FoV within the first FoV. The second FoV is provided with a higher, second resolution. In some cases, all of the light pulses are directed through the optical element to the second FoV. In other cases, the first FoV continues to be scanned at a reduced resolution. A rotatable polygon, micromirrors and/or solid state array mechanisms can be used to divert the pulses to the optical element.

The present invention is directed to electrical circuits and methods. According to a specific embodiment, the present invention provides a voltage compensation mechanism for one or more single-phone avalanche diodes (SPADs). A reference voltage is generated based at least on an operating voltage of the SPADs. The reference voltage is coupled to a charge pump that generates a compensation voltage for the diodes. There are other embodiments as well.

A light detection and ranging (LiDAR) device and an operating method thereof include irradiating a laser light toward an object; outputting a laser reflection light signal by detecting the laser light reflected from the object; measuring a pulse width corresponding to a period in which the laser reflection light signal is saturated from the laser reflection light signal and changing at least one of a laser light intensity to be irradiated by the laser light irradiator or a gain of an amplifier according to the analyzed pulse width; and controlling the laser light irradiator to irradiate an adjusted laser light corresponding to the changing.

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.

A circuit for filtering a signal corresponding to a time of flight (TOF) of light from a laser reflected off an object to a photo detector, the circuit includes a preamplifier, a DC cancelation loop, and an AC cancelation loop. The preamplifier may be configured to receive the signal from the photo detector corresponding to an output of the laser reflected off an object remote from the laser and photo detector. The DC cancelation loop includes a current feedback DC servo loop. The AC cancelation loop includes a feedback network driven by a floating class AB output stage, and the preamplifier configured to drive the floating class AB output stage, wherein the preamplifier is driven by an error signal of the feedback network and creates an AC signal path with the feedback network and floating class AB output stage.