Abstract: A method for multipath error compensation comprises an unstructured light source (142) illuminating a scene during a plurality of consecutive time frames. A structured light source (144) illuminates the scene concurrently, the illumination by the structured source (144) occurring during predetermined frames of the plurality of consecutive time frames. An array of photodetectors (102) each generate a set of signals in response to irradiation with light reflected from the scene according to an indirect time of flight calculation technique to yield a plurality of sets of signals. An error estimate is derived (130) from the plurality of sets of signals generated during a selected time frame of the plurality of consecutive time frames when structured illumination takes place and another time frame temporally about the selected time frame when both structured and unstructured illumination takes place. The error estimate is applied in a range calculation with respect to the scene.

Abstract: A method of generating a time domain echo waveform comprises: a triggered source of pulsed electromagnetic radiation (108) emitting (202) a plurality of electromagnetic radiation pulses (132). A plurality of reflected pulses (134) irradiates an electromagnetic radiation detector cell (116), the detector (116) generating a plurality of stored electrical measurements in response thereto. The method also comprises generating a time-varying mixing signal and respectively applying (204, 206) phase-shifted variations thereof to the detector (116) while generating the plurality of electrical measurements. A signal pre-processor (126) reads out (210) the plurality of electrical measurements from the detector (116). A signal reconstruction unit (128) and then generates (300, 302, 500, 502) a spectrum (404, 604) in respect of the electrical measurements and a spectrum (406, 606) of the mixing signal.

Abstract: A pixel circuit wherein a pixel arrangement comprises a pixel comprising a photodetector, an integrator for accumulating a signal from the photodetector, a source following output transistor for amplifying the integrated signal, and a current source for applying a readout current through the output transistor, a voltage regulating circuit comprising an amplifier, a replica transistor dimensioned substantially the same as the output transistor, and a replica current source for providing substantially the readout current through each replica transistor, a gate of the replica transistor is connected with an output node of the amplifier connected with the pixel arrangement, and a source of the replica transistor is connected with a negative input of the amplifier, and with the replica current source, a predefined reference voltage is applicable to a positive input.

Abstract: A photonic mixer device for multiplying an impinging optical signal with a reference electrical signal includes: a semiconductor substrate of a first conductivity type; two detector regions of a second conductivity type different from the first conductivity type; two biasing regions of the first conductivity type with a higher dopant concentration than the dopant concentration of the semiconductor substrate, each biasing region positioned near one of the respective detector regions, wherein an electrical field can be formed in the semiconductor substrate by applying a voltage bias between the biasing regions; two bias electrodes, which are isolated from the substrate and the biasing regions, wherein each bias electrode is only locally, partially or completely, covering an outer edge of one of the respective biasing regions.

Abstract: A depth mapping system includes a time of flight ranging system including structured and unstructured light sources, an optical sensor unit and a signal processing unit. The system time employs first and second time of flight ranging technique in respect of the optical sensor unit. The first and second time of flight techniques measure respective first and second distance ranges over a first and a second respective field of view. Measurement of the first and second distance ranges are respectively at a first angular resolution and a second angular resolution greater than the first angular resolution. The structured and unstructured light sources respectively operate in respect of the first and second time of flight techniques. First and second regions of the optical sensor unit respectively have the first and second fields of view associated therewith, and the structured source has a greater emission radiant intensity than the unstructured source.

Abstract: A depth mapping system comprises a time of flight ranging system (200) comprising structured and unstructured light sources (116, 118), an optical sensor unit (202) and a signal processing unit (206). The system time multiplexes use of first and second time of flight ranging technique in respect of the optical sensor unit (202). The first and second time of flight techniques measure respective first and second distance ranges over a first and a second respective field of view. Measurement of the first and second distance ranges are respectively at a first angular resolution and a second angular resolution greater than the first angular resolution. The structured and unstructured light sources (116, 118) respectively operate in respect of the first and second time of flight techniques. First and second regions of the optical sensor unit (202) respectively have the first and second fields of view associated therewith.

Abstract: A method for multipath error compensation comprises an unstructured light source (142) illuminating a scene during a plurality of consecutive time frames. A structured light source (144) illuminates the scene concurrently, the illumination by the structured source (144) occurring during predetermined frames of the plurality of consecutive time frames. An array of photodetectors (102) each generate a set of signals in response to irradiation with light reflected from the scene according to an indirect time of flight calculation technique to yield a plurality of sets of signals. An error estimate is derived (130) from the plurality of sets of signals generated during a selected time frame of the plurality of consecutive time frames when structured illumination takes place and another time frame temporally about the selected time frame when both structured and unstructured illumination takes place. The error estimate is applied in a range calculation with respect to the scene.

Abstract: A phase angle error calculation apparatus (100) comprising a light source (102) that emits light according to an indirect time of flight (iToF) measurement technique. A photonic mixer cell (104) generates and stores a plurality of electrical output signals corresponding to a plurality of predetermined phase offset values. A signal processing circuit processes the electrical output signals according to the iToF measurement technique in order to calculate a reference vector and a reference phase angle therefrom. The output signals correspond to measurement at a first level of precision. The circuit processes a subset of output signals according to the iToF measurement technique and calculates a measurement vector and a measurement phase angle therefrom. The subset of the output signals corresponds to measurement at a second level of precision lower than the first level of precision. The circuit calculates a phase angle correction value using the reference phase angle and the measurement phase angle.

Abstract: A multi-channel light detection and ranging system includes a plurality of active channels, each comprising a photosensitive element arranged to be exposed to light and an analog front end circuit arranged for receiving a signal from the photosensitive element. A compensation channel comprises a compensation element and an analog front end circuit arranged for receiving signals from the compensation capacitor. A processing unit arranged for receiving signals from the active channels and the compensation channel, deriving at a compensation signal from the signal received from the compensation channel, and compensating for the crosstalk interference and/or the interference common to the analog front end circuits of the active channels, using the compensation signal.

Abstract: A signal peak detection apparatus (122) comprises an analogue signal source input and a plurality of analogue temporary storage units (140) operably coupled to the analogue signal source input. Each analogue temporary storage unit is configured in successive time-window relation to a preceding analogue temporary storage unit of the plurality of analogue temporary storage units (140). A gradient direction measurement unit (146) is operably coupled to the plurality of analogue temporary storage units (140) and configured to cooperate with the plurality of analogue temporary storage units (140) to provide waveform portion-specific gradient data in an n-bit digital output format. The apparatus (122) also comprises a waveform analyser (152) comprising a bitstream state change detector (154) and an m-bit input operably coupled thereto, the m-bit input being operably coupled to the gradient direction measurement unit (146).

Abstract: A sample and hold system, for capturing and reading a sequence of traces of an input signal. The sample and hold system comprising a readout device, a controller, and a sample and hold array of unit cells. The controller is configured for controlling the sample and hold system, such that during an acquisition phase a trace of samples is taken from the input signal in an original sample order and such that the samples are held in the unit cells wherein the samples are assigned to the unit cells in an acquisition order, such that during a consecutive readout phase the samples are read out from the unit cells wherein the order in which the unit cells are read out corresponds with a readout order, and such that the acquisition order and/or the readout order differs from trace to trace.

Abstract: A pixel circuit for performing Time of Flight measurements comprises at least one optical sensor arranged for receiving a reference modulation signal and a light signal and arranged for outputting a photocurrent signal depending on the light signal and on a phase shift corresponding to a phase difference between the light signal and the reference modulation signal, and an integrator circuit comprising an integration capacitor, an amplifier, and switching mean. The switching means is arranged for resetting the integration capacitor in a reset mode, for connecting the integration capacitor between the at least one optical sensor and a voltage reference signal in a passive mode. The negative feedback loop is fed with the photocurrent signal of the at least one optical sensor, and for connecting a signal output by the integrator circuit to an output bus in a readout mode.

Abstract: A method of generating a time domain echo waveform comprises: a triggered source of pulsed electromagnetic radiation (108) emitting (202) a plurality of electromagnetic radiation pulses (132). A plurality of reflected pulses (134) irradiates an electromagnetic radiation detector cell (116), the detector (116) generating a plurality of stored electrical measurements in response thereto. The method also comprises generating a time-varying mixing signal and respectively applying (204, 206) phase-shifted variations thereof to the detector (116) while generating the plurality of electrical measurements. A signal pre-processor (126) reads out (210) the plurality of electrical measurements from the detector (116). A signal reconstruction unit (128) and then generates (300, 302, 500, 502) a spectrum (404, 604) in respect of the electrical measurements and a spectrum (406, 606) of the mixing signal.

Abstract: A semiconductor pixel unit for sensing near-infrared light, and for optionally simultaneously sensing visible light. The pixel unit comprises a single substrate with a first semiconductor region and a second semiconductor region electrically separated by an insulating region, for example a buried oxide layer. The pixel unit is adapted for generating a lateral electrical field in the second region for facilitating transport of photoelectrons generated in the second region by near-infrared light passing through the first region and the insulating region.

Abstract: A pixel circuit wherein a pixel arrangement comprises a pixel comprising a photodetector, an integrator for accumulating a signal from the photodetector, a source following output transistor for amplifying the integrated signal, and a current source for applying a readout current through the output transistor, a voltage regulating circuit comprising an amplifier, a replica transistor dimensioned substantially the same as the output transistor, and a replica current source for providing substantially the readout current through each replica transistor, a gate of the replica transistor is connected with an output node of the amplifier connected with the pixel arrangement, and a source of the replica transistor is connected with a negative input of the amplifier, and with the replica current source, a predefined reference voltage is applicable to a positive input.

Abstract: A sample and hold system, for capturing and reading at least one input signal. The system comprises a readout device, a controller, an array of segments comprising a plurality of unit cells and a dummy unit cell, and segment switches between the segments and the readout device. The controller is adapted for controlling the system such that: during an acquisition phase a trace of samples is taken from the input signal and held in the unit cells; during a readout phase the samples in the unit cells or in the dummy unit cells of a segment are read out by readout device; after opening or closing the segment switches the dummy unit cell, is the first cell which is read out by the readout device.

Abstract: A semiconductor pixel unit for sensing near-infrared light, and for optionally simultaneously sensing visible light. The pixel unit comprises a single substrate with a first semiconductor region and a second semiconductor region electrically separated by an insulating region, for example a buried oxide layer. The pixel unit is adapted for generating a lateral electrical field in the second region for facilitating transport of photoelectrons generated in the second region by near-infrared light passing through the first region and the insulating region.

Abstract: A method for noise reduction in an imaging device comprises a 4T pixel in operation, whereby the 4T pixel comprises a pinned photodiode and a floating diffusion node. The method includes the steps of: detecting a signal impinging on the 4T pixel of the imaging device and integrating the charge of the detected signal simultaneously in the photodiode potential well and the potential well of the floating diffusion node; deriving a linear signal proportional to the detected signal from the charge in the photodiode potential well; deriving a compressed signal from the charge in the potential well of the floating diffusion node, while keeping the compressed signal separate from the linear signal, and the compressed signal being a non-linear function of the detected signal; and summing the linear signal and a linearized version of the compressed signal and performing a non-linear conversion on the summation signal to fit the imaging device's output range.

Abstract: A pixel circuit for performing Time of Flight measurements comprises at least one optical sensor arranged for receiving a reference modulation signal and a light signal and arranged for outputting a photocurrent signal depending on the light signal and on a phase shift corresponding to a phase difference between the light signal and the reference modulation signal, and an integrator circuit comprising an integration capacitor, an amplifier, and switching mean. The switching means is arranged for resetting the integration capacitor in a reset mode, for connecting the integration capacitor between the at least one optical sensor and a voltage reference signal in a passive mode. The negative feedback loop is fed with the photocurrent signal of the at least one optical sensor, and for connecting a signal output by the integrator circuit to an output bus in a readout mode.

Abstract: A semiconductor pixel unit for sensing near-infrared light, and for optionally simultaneously sensing visible light. The pixel unit comprises a single substrate with a first semiconductor region and a second semiconductor region electrically separated by an insulating region, for example a buried oxide layer. The pixel unit is adapted for generating a lateral electrical field in the second region for facilitating transport of photoelectrons generated in the second region by near-infrared light passing through the first region and the insulating region.