Patent ID: 8885111

Claim:
An optical node device comprising: a light receiving/emitting portion comprising an input port into which a signal beam is incident and an output port that emits a signal beam of a selected wavelength; a chromatic dispersion device that scatters spatially the signal beam depending on the wavelength of the signal beam; an optical coupler that focuses, onto a two-dimensional plane, beams dispersed by the chromatic dispersion device; a spatial light modulating element arranged so as to receive incident light deployed on an xy plane made up of an x-axis direction deployed according to wavelength and a y-axis direction orthogonal to the x-axis direction, and comprising a plurality of pixels arranged in a lattice on the xy plane; and a spatial light modulating element driving portion that drives electrodes of individual pixels of the plurality of pixels arranged in the xy axial directions in the spatial light modulating element so as to either reflect or transmit each of the beams having an individual wavelength in a respective direction; the plurality of pixels comprising: a liquid crystal element in which a liquid crystal layer is interposed between a mutually facing pixel electrode and common electrode; a first sampling circuit that samples a positive polarity pixel signal and holds it for a specific time period; a second sampling circuit that samples a negative polarity pixel signal and holds it for the specific time period; and a switching circuit that switches alternatingly a positive polarity signal voltage and a negative polarity signal voltage, stored respectively by the first and second sampling circuits, to the pixel electrode by switching, with a predetermined frequency that is higher than a vertical scanning frequency.