A system and sensor for measuring, inspecting, characterizing, evaluating and/or controlling optical lithographic equipment and/or materials used therewith, for example, photomasks. In one embodiment, the system and sensor measures, collects and/or detects an aerial image (or portion thereof) produced or generated by the interaction between the photomask and lithographic equipment. An image sensor unit may measure, collect, sense and/or detect the aerial image in situ—that is, the aerial image at the wafer plane produced, in part, by a production-type photomask (i.e., a wafer having integrated circuits formed therein/thereon) and/or by associated lithographic equipment used, or to be used, to manufacture of integrated circuits. A processing unit, coupled to the image sensor unit, may generate image data which is representative of the aerial image by, in one embodiment, interleaving the intensity of light sampled by each sensor cell at the plurality of location of the platform. Notably, there are many inventions/embodiments disclosed herein.