1. An interactive input system comprising: a bezel at least partially surrounding a region of interest, a surface of said bezel facing said region of interest having a plurality of generally parallel, longitudinally extending bands thereon with all adjacent bands having different optical properties and wherein said bands comprise at least one band that reflects illumination and at least one band that absorbs illumination, all of said longitudinally extending bands being adapted to be disposed above a display surface within the region of interest; at least one imaging device looking into said region of interest in a direction substantially orthogonal to the plane of the surface of said longitudinally extending bands and seeing the surface of said at least one bezel so that images acquired by said at least one imaging device comprise regions corresponding to said bands; and processing structure processing pixels corresponding to the adjacent bands having different optical properties to detect the existence of a pointer in said region of interest, wherein during said processing, said processing structure determines differences between pixel intensity profiles calculated for each of said adjacent bands and compares the pixel intensity profile of each of said adjacent bands to detect at least one discontinuity between adjacent bands.