Abstract: A time-of-flight (ToF) camera is configured to illuminate a subject with IR light. For each sensor of a sensor array, camera space coordinates of a locus of the subject are determined based on the measured IR light. The camera space coordinates include a phase difference between emitted IR light and reflected IR light. A plurality of candidate positions of the locus of the subject are determined in world space based on the camera space coordinates. Each candidate position corresponds to a different phase wrapping of the phase difference. A phase wrapping is determined based on performing a searching algorithm on the different candidate positions. A depth value for the sensor is calculated based on the phase difference and the phase wrapping determined from performing the searching algorithm. A matrix of pixels is outputted from the camera. Each pixel of the matrix includes a depth value.

Abstract: A camera includes a time-of-flight illuminator configured to emit active IR light and a plurality of spectral illuminators, each spectral illuminator configured to emit active spectral light in a different spectral light sub-band. The camera further includes a sensor array that includes a plurality of differential sensors. Each differential sensor is configured to differentially measure both 1) the active IR light, and 2) the active spectral light in each of the different spectral light sub-bands. The camera further includes an output machine operatively connected to the sensor array. The output machine is configured to output a matrix of pixels based on time-multiplexed measurements of the sensor array. Each pixel of the matrix includes 1) a depth value, and 2) a plurality of spectral values. Each of the plurality of spectral values corresponds to a spectral light sub-band of one of the plurality of spectral illuminators.

Abstract: A camera includes an optical filter for a sensor array of the camera. The optical filter includes a plurality of liquid crystal layers switchable between a reflection state and a transmission state. Each liquid crystal layer is configured to block spectral light in a different spectral light sub-band and transmit spectral light outside of the spectral light sub-band in the reflection state, and to transmit spectral light in the spectral light sub-band in the transmission state. An active illuminator of the camera is configured to emit active light in a selected spectral light sub-band. One or more of the plurality of liquid crystal layers is switched from the transmission state to the reflection state to tune the optical filter to block spectral light in all but the selected spectral light sub-band. The sensors of the sensor array are addressed to measure spectral light in the selected spectral light sub-band.

Abstract: A camera is configured to output a test depth+multi-spectral image including a plurality of pixels. Each pixel corresponds to one of the plurality of sensors of a sensor array of the camera and includes at least a depth value and a spectral value for each spectral light sub-band of a plurality of spectral illuminators of the camera. An object recognition machine is previously trained with a set of labeled training depth+multi-spectral images having a same structure as the test depth+multi-spectral image. The object recognition machine is configured to output a confidence value indicating a likelihood that the test depth+multi-spectral image includes a specified object.

Abstract: Features of the present disclosure implement an analytical formalism to calculate a time of flight (ToF) for a signal in order to identify the distance between the ToF imaging system and a target object. The features of the present disclosure allow a flexible, fast, and accurate solution for phase unwrapping in ToF imaging system. Such techniques minimize the memory usage, accounts for the factors that generally contribute to differences in the performance of the selected modulation frequencies, and mitigates the unwrapping errors that occur in low signal to noise areas.

Abstract: A time-of-flight (ToF) system disclosed herein provides a method of separating a direct component of light collected by a time of flight (ToF) detector from a global component of light collected by the ToF detector by acquiring a first image represented by a first matrix in response to illuminating a target with a light source using a first spatial pattern, acquiring a second image represented by a second matrix in response to illuminating the target with the light source using a second spatial pattern, the second spatial pattern being different than the first spatial pattern, and determining one or more parameters of the direct component of light and the global component of light based on analysis of the first matrix and the second matrix.