Patent ID: 7319507

Claim:
An apparatus comprising: an original stage configured to hold an original and to move in a scan direction; an illumination optical system configured to illuminate the original held by said original stage with exposure light; a substrate stage configured to hold a substrate and to move in a scan direction; a projection optical system configured to project a pattern of the original onto the substrate with the exposure light; and an irradiation unit configured to irradiate the original held by said original stage with light of which wavelength is different from wavelength of the exposure light, wherein said irradiation unit irradiates the original held by said original stage while the original is moved in the scan direction by said original stage so as to remove contaminant on the original, and wherein while said illumination optical system illuminates a first area on the original with the exposed light, said irradiation unit irradiates a second area on the original different from the first area.