An illuminator system comprising an illuminator array positioned adjacent to an image bearing surface, the illuminator array comprising a plurality of discrete illuminator elements spaced in a linear arrangement, the illuminating elements each being configured to emit a light beam for transmission to the image bearing surface at an incidence angle; a light diffuser comprising a plurality of rounded lenslets having convex or concave configuration positioned between the illuminator array and the image bearing surface, the rounded lenslets being positioned with respect to the illuminator array to receive the light beams emitted by the illuminator elements and to diffuse the light beams being transmitted to the image bearing surface in the linear direction of the illuminator array; and a linear sensor array comprising a plurality of sensors positioned adjacent to the image bearing surface such that the light beams reflecting off the image bearing surface at a reflectance angle are received by the sensors.