Patent ID: 7656503

Claim:
An exposure apparatus, comprising: an illumination optical system configured to illuminate an original, with exposure light of plural wavelengths, from a light source; a projection optical system configured to project an image of a pattern of the original onto a substrate; an original-side reference pattern provided at an original side of said projection optical system; a substrate-side reference pattern provided at a substrate side of said projection optical system; and image plane detecting means configured so that the original-side reference pattern is illuminated with the exposure light or light equivalent to the exposure light with respect to a wavelength component rate whereby an image of the original-side reference pattern is projected onto the substrate-side reference pattern through said projection optical system, and that an image plane position of said projection optical system is detected on the basis of a quantity of light transmitted through or reflected by the substrate-side reference pattern, wherein the original-side reference pattern and the substrate-side reference pattern to be used with said image plane detecting means for detection of the image plane position at an axial image height of said projection optical system comprises a plurality of slit-like patterns arrayed in a sagittal direction of said projection optical system and a plurality of slit-like patterns arrayed in a meridional direction of said projection optical system, wherein the original-side reference pattern and the substrate-side reference pattern to be used with said image plane detecting means for detection of the image plane position in the sagittal direction at an abaxial image height of said projection optical system comprises a plurality of slit-like patterns arrayed in the sagittal direction, and wherein the image plane position in the meridional direction at the abaxial image height is calculated based on (i) a predetermined relationship between an amount of change of the image plane in the sagittal direction and that in the meridional direction, and (ii) the image plane position in the sagittal direction at the abaxial image height as detected by said image plane detecting means.