Abstract: A computing device includes a system that authenticates a user of the computing device. A first sensor obtains a first representation of a physical characteristic of the user that is compared to a registered representation of the physical characteristic of the user. A first level of access to the computing device is enabled based on the first representation of the physical characteristic matching the second representation of the physical characteristic. A second sensor obtains a first representation of a liveness characteristic of the user that indicates that the user is alive. The first representation of the liveness characteristic is compared to a registered representation of the liveness characteristic of the user. A second level of access to the computing device is enabled based on the first representation of the liveness characteristic of the user matching the second representation of the liveness characteristic of the user.

Abstract: A time-resolving sensor includes a single-photon avalanche diode (SPAD), a logic circuit and differential time-to-charge converter (DTCC) circuit. The SPAD is responsive to a shutter signal to generate an output signal based on detecting an incident photon. The logic circuit generates first and second enable signals. The DTCC includes a capacitor device, first and second switching devices, and an output circuit. The first switching device is responsive to the first enable signal to transfer a charge on the capacitor device to the first floating diffusion. The second switching device is responsive to the second enable signal to transfer a remaining charge on the capacitor device to the second floating diffusion. The output circuit outputs a first voltage that is based on the first charge on the first floating diffusion and a second voltage that is based on the second charge on the second floating diffusion.

Abstract: A pixel of an image sensor includes a pinned photodiode (PPD), a switching device and an output circuit. A first terminal of the switching device is coupled to the PPD. A second terminal of the switching device is coupled to a floating diffusion (FD). A third terminal of the switching device is coupled to a first enable signal and a second enable signal. The switching device is responsive to the first enable signal to transfer a first charge on the PPD to the FD, and responsive to the second enable signal to transfer a second charge on the PPD to the FD. The output circuit outputs a first voltage based on the first charge and outputs a second voltage based on the second charge in which the first voltage corresponds to a time of flight of one or more detected photons and the second voltage corresponds to a greyscale image.

Abstract: A system and a method determines a traveling time for a light pulse between a light pulse source and a pixel of a light sensor array based on a “Find Frequent Items in a Data Steam” technique. In one embodiment, raw timestamp data output from a pixel as a data stream may be temporarily stored, processed twice and then discarded to provide an exact determination of a traveling time estimate. In another embodiment, the raw timestamp data is processed once and discarded to provide an approximate determination of a traveling time estimate. The traveling time estimate may be updated during processing and the most-frequently occurring timestamp is available when processing the data stream is complete. There is no need to keep the raw data in a memory, thereby reducing the memory requirement associated with determining the traveling time of a light pulse.

Abstract: Using the same image sensor to capture both a two-dimensional (2D) image of a three-dimensional (3D) object and 3D depth measurements for the object. A laser point-scans the surface of the object with light spots, which are detected by a pixel array in the image sensor to generate the 3D depth profile of the object using triangulation. Each row of pixels in the pixel array forms an epipolar line of the corresponding laser scan line. Timestamping provides a correspondence between the pixel location of a captured light spot and the respective scan angle of the laser to remove any ambiguity in triangulation. An Analog-to-Digital Converter (ADC) in the image sensor generates a multi-bit output in the 2D mode and a binary output in the 3D mode to generate timestamps. Strong ambient light is rejected by switching the image sensor to a 3D logarithmic mode from a 3D linear mode.

Abstract: A Time-of-Flight (TOF) technique is combined with analog amplitude modulation within each pixel in a pixel array using multiple Single Photon Avalanche Diodes (SPADs) in conjunction with a single Pinned Photo Diode (PPD) in each pixel. A SPAD may be shared among multiple neighboring pixels. The TOF information is added to the received light signal by the analog domain-based single-ended to differential converter inside the pixel itself. The spatial-temporal correlation among outputs of multiple, adjacent SPADs in a pixel is used to control the operation of the PPD to facilitate recording of TOF values and range of an object. Erroneous range measurements due to ambient light are prevented by stopping the charge transfer from the PPD—and, hence, recording a TOF value—only when two or more SPADs in the pixel are triggered within a pre-defined time interval. An autonomous navigation system with multi-SPAD pixels provides improved vision for drivers under difficult driving conditions.

Abstract: A Dynamic Vision Sensor (DVS) pose-estimation system includes a DVS, a transformation estimator, an inertial measurement unit (IMU) and a camera-pose estimator based on sensor fusion. The DVS detects DVS events and shapes frames based on a number of accumulated DVS events. The transformation estimator estimates a 3D transformation of the DVS camera based on an estimated depth and matches confidence-level values within a camera-projection model such that at least one of a plurality of DVS events detected during a first frame corresponds to a DVS event detected during a second subsequent frame. The IMU detects inertial movements of the DVS with respect to world coordinates between the first and second frames. The camera-pose estimator combines information from a change in a pose of the camera-projection model between the first frame and the second frame based on the estimated transformation and the detected inertial movements of the DVS.

Abstract: Using the same image sensor to capture both a two-dimensional (2D) image of a three-dimensional (3D) object and 3D depth measurements for the object. A laser point-scans the surface of the object with light spots, which are detected by a pixel array in the image sensor to generate the 3D depth profile of the object using triangulation. Each row of pixels in the pixel array forms an epipolar line of the corresponding laser scan line. Timestamping provides a correspondence between the pixel location of a captured light spot and the respective scan angle of the laser to remove any ambiguity in triangulation. An Analog-to-Digital Converter (ADC) in the image sensor generates a multi-bit output in the 2D mode and a binary output in the 3D mode to generate timestamps. Strong ambient light is rejected by switching the image sensor to a 3D logarithmic mode from a 3D linear mode.

Abstract: Using the same image sensor to capture both a two-dimensional (2D) image of a three-dimensional (3D) object and 3D depth measurements for the object. A laser point-scans the surface of the object with light spots, which are detected by a pixel array in the image sensor to generate the 3D depth profile of the object using triangulation. Each row of pixels in the pixel array forms an epipolar line of the corresponding laser scan line. Timestamping provides a correspondence between the pixel location of a captured light spot and the respective scan angle of the laser to remove any ambiguity in triangulation. An Analog-to-Digital Converter (ADC) in the image sensor generates a multi-bit output in the 2D mode and a binary output in the 3D mode to generate timestamps. Strong ambient light is rejected by switching the image sensor to a 3D logarithmic mode from a 3D linear mode.

Abstract: A method is disclosed to determine a traveling time for a plurality of received light pulses that reflected and returned from an object. Each returned light pulse is associated with a timestamp indicating a time between a transmission time of a corresponding light pulse and a time of arrival of the returned light pulse. For each timestamp, a number C is determined of time stamps that are subsequent to the timestamp and within a predetermined time window after the timestamp. A maximum number C is determined, and an index i is determined for the maximum number C. A traveling time is determined for the plurality of light pulses as an average of the timestamp having a same index as the maximum number C and timestamps that are within the predetermined time window after the timestamp having the same index as the maximum number C.

Abstract: Using the same image sensor to capture both a two-dimensional (2D) image of a three-dimensional (3D) object and 3D depth measurements for the object. A laser point-scans the surface of the object with light spots, which are detected by a pixel array in the image sensor to generate the 3D depth profile of the object using triangulation. Each row of pixels in the pixel array forms an epipolar line of the corresponding laser scan line. Timestamping provides a correspondence between the pixel location of a captured light spot and the respective scan angle of the laser to remove any ambiguity in triangulation. An Analog-to-Digital Converter (ADC) in the image sensor generates a multi-bit output in the 2D mode and a binary output in the 3D mode to generate timestamps. Strong ambient light is rejected by switching the image sensor to a 3D logarithmic mode from a 3D linear mode.

Abstract: A method is disclosed to determine a traveling time for a plurality of received light pulses that reflected and returned from an object. Each returned light pulse is associated with a timestamp indicating a time between a transmission time of a corresponding light pulse and a time of arrival of the returned light pulse. For each timestamp, a number C is determined of time stamps that are subsequent to the timestamp and within a predetermined time window after the timestamp. A maximum number C is determined, and an index i is determined for the maximum number C. A traveling time is determined for the plurality of light pulses as an average of the timestamp having a same index as the maximum number C and timestamps that are within the predetermined time window after the timestamp having the same index as the maximum number C.

Abstract: An apparatus and a method are provided. The apparatus includes a light source configured to project light in a changing pattern that reduces the light's noticeability; collection optics through which light passes and forms an epipolar plane with the light source; and an image sensor configured to receive light passed through the collection optics to acquire image information and depth information simultaneously. The method includes projecting light by a light source in a changing pattern that reduces the light's noticeability; passing light through collection optics and forming an epipolar plane between the collection optics and the light source; and receiving in an image sensor light passed through the collection optics to acquire image information and depth information simultaneously.

Abstract: A time-resolving sensor includes a single-photon avalanche diode (SPAD), a logic circuit and differential time-to-charge converter (DTCC) circuit. The SPAD is responsive to a shutter signal to generate an output signal based on detecting an incident photon. The logic circuit generates first and second enable signals. The DTCC includes a capacitor device, first and second switching devices, and an output circuit. The first switching device is responsive to the first enable signal to transfer a charge on the capacitor device to the first floating diffusion. The second switching device is responsive to the second enable signal to transfer a remaining charge on the capacitor device to the second floating diffusion. The output circuit outputs a first voltage that is based on the first charge on the first floating diffusion and a second voltage that is based on the second charge on the second floating diffusion.

Abstract: A range sensor and a method thereof. The range sensor includes a light source configured to project a plurality of sheets of light at an angle within a field of view (FOV); an image sensor, wherein the image sensor is offset from the light source; collection optics; and a controller connected to the light source, the image sensor, and the collection optics, and configured to simultaneously determine a range of a distant object based on direct time-of-flight (TOF) and a range of a near object based on triangulation.

Abstract: The Time-of-Flight (TOF) technique is combined with analog amplitude modulation within each pixel in an image sensor. The pixel may be a two-tap pixel or a one-tap pixel. Two photoelectron receiver circuits in the pixel receive respective analog modulating signals. The distribution of the received photoelectron charge between these two circuits is controlled by the difference (or ratio) of the two analog modulating voltages. The differential signals generated in this manner within the pixel are modulated in time domain for TOF measurement. Thus, the TOF information is added to the received light signal by the analog domain-based single-ended to differential converter inside the pixel itself. The TOF-based measurement of range and its resolution are controllable by changing the duration of modulation. An autonomous navigation system with these features may provide improved vision for drivers under difficult driving conditions like low light, fog, bad weather, or strong ambient light.

Abstract: A Dynamic Vision Sensor (DVS) pose-estimation system includes a DVS, a transformation estimator, an inertial measurement unit (IMU) and a camera-pose estimator based on sensor fusion. The DVS detects DVS events and shapes frames based on a number of accumulated DVS events. The transformation estimator estimates a 3D transformation of the DVS camera based on an estimated depth and matches confidence-level values within a camera-projection model such that at least one of a plurality of DVS events detected during a first frame corresponds to a DVS event detected during a second subsequent frame. The IMU detects inertial movements of the DVS with respect to world coordinates between the first and second frames. The camera-pose estimator combines information from a change in a pose of the camera-projection model between the first frame and the second frame based on the estimated transformation and the detected inertial movements of the DVS.

Abstract: An imaging unit includes a light source and a pixel array. The light source projects a line of light that is scanned in a first direction across a field of view of the light source. The line of light oriented in a second direction that is substantially perpendicular to the first direction. The pixel array is arranged in at least one row of pixels that extends in a direction that is substantially parallel to the second direction. At least one pixel in a row is capable of generating two-dimensional color information of an object in the field of view based on a first light reflected from the object and is capable of generating three-dimensional (3D) depth information of the object based on the line of light reflecting from the object. The 3D-depth information includes time-of-flight information.

Abstract: An image sensor includes a time-resolving sensor and a processor. The time-resolving sensor outputs a first signal and a second signal pair in response detecting one or more photons that have been reflected from an object. A first ratio of a magnitude of the first signal to a sum of the magnitude of the first signal and a magnitude of the second signal is proportional to a time of flight of the one or more detected photons. A second ratio of the magnitude of the second signal to the sum of the magnitude of the first signal and the magnitude of the second signal is proportional to the time of flight of the one or more detected photons. The processor determines a surface reflectance of the object where the light pulse has been reflected based on the first signal and the second signal pair and may generate a grayscale image.

Abstract: An apparatus and a method are provided. The apparatus includes a light source configured to project light in a changing pattern that reduces the light's noticeability; collection optics through which light passes and forms an epipolar plane with the light source; and an image sensor configured to receive light passed through the collection optics to acquire image information and depth information simultaneously. The method includes projecting light by a light source in a changing pattern that reduces the light's noticeability; passing light through collection optics and forming an epipolar plane between the collection optics and the light source; and receiving in an image sensor light passed through the collection optics to acquire image information and depth information simultaneously.