Image sensor with optical filters having alternating polarization for 3D imaging

An imaging system for three-dimensional (“3D”) imaging, the system comprising:

• a first channel for generating a first view of a 3D object;
• a second channel for generating a second view of the 3D object;
• a beam splitter coupled to the first and second channels to combine the first and second views to output polarization-encoded light having a first polarization corresponding to the first view of the 3D object and a second polarization corresponding to the second view of the 3D object;
• and
• an image sensor coupled to receive the polarization-encoded light, the image sensor including:
• a pixel array comprising a plurality of pixel units arranged in rows and columns, each pixel unit including four imaging pixels arranged into a Bayer pattern;
• and
• a polarizer array optically coupled to the pixel array to filter the polarization-encoded light, the polarizer array comprising a plurality of polarizing filters wherein each pixel unit in the pixel array is optically coupled to a corresponding polarizing filter in the polarizer array, and wherein the polarizations of all polarizing filters in the polarizer array are selected from a set of two orthogonal polarizations consisting of the first polarization and the second polarization;
• wherein each imaging pixel comprises:
• a photosensing region disposed in a semiconductor layer of the image sensor;
• a color filter disposed on the light-incident side of the image sensor;
• and
• a microlens disposed on the light incident side to focus incident light to the photosensing region.