A 3D imaging system includes an optical modulator for modulating a returned portion of a light pulse as a function of time. The returned light pulse portion is reflected or scattered from a scene for which a 3D image or video is desired. The 3D imaging system also includes an element array receiving the modulated light pulse portion and a sensor array of pixels, corresponding to the element array. The pixel array is positioned to receive light output from the element array. The element array may include an array of polarizing elements, each corresponding to one or more pixels. The polarization states of the polarizing elements can be configured so that time-of-flight information of the returned light pulse can be measured from signals produced by the pixel array, in response to the returned modulated portion of the light pulse.