1. An exposure apparatus that exposes an object with a pattern image, the apparatus comprising: a pattern image generation device which generates a pattern image corresponding to an input of a design data; a detection system which photoelectrically detects at least a part of the pattern image that has been generated or image generated and formed on the object; and a correction device which corrects the design data that should be input to the pattern image generation device based on results of the detection, wherein the pattern image generation device generates the pattern image via a variable shaped mask that spatially modulates at least one of an amplitude, a phase, and a state of polarization of light according to the input of the design data.