A magneto photonic encoder, in plane, includes a set of periodic structures of magneto photonic crystals for rotating a polarization of a beam of light responsive to a controllable magnetic field as it is transmitted through the periodic structures. The rotated polarization, in cooperation with a non-reciprocal-mode conversion device produces an encoded signal without use of crossed polarizers. Path optics guide the light beam into the periodic structures for polarization rotation and then to direct the modified beam of light into the non-reciprocal-mode conversion device. Depending upon the implementation, the encoded output may serve as display image primitive precursor to produce an image constituent signal.