Patent ID: 8463125

Claim:
An optically variable filter array apparatus comprising: an entrance/exit section for a plurality of channels arranged along a direction of a y axis, which receives WDM signal light beams of a first to m-th channels, each of which is composed of multi-wavelength light, and allows exit of optical signals of selected multiplex wavelengths on a channel to channel basis; a wavelength dispersion element which spatially disperses said WDM signal light beams of different channels according to their wavelengths; a light condensing element which condenses the WDM light beams of different channels dispersed by said wavelength dispersion element on a two-dimensional xy plane; a wavelength selection element which has a multiplicity of pixels that are arranged in a direction of an x axis according to wavelength, are placed so as to receive incoming light beams of m channels arranged at different positions with respect to the y axis so as to be developed over the xy plane, and are arranged in a lattice pattern on the xy plane, and which selects light in a desired number of wavelength bands with respect to a desired number of said light beams by changing reflection characteristics of each of the pixels arranged in a two-dimensional fashion; and a wavelength selection element driving unit which drives an electrode of each of the pixels arranged in the x-y directions of said wavelength selection element to control light reflection characteristics of a pixel lying at a predetermined position in the x-axis direction as well as in the y-axis direction.