An exposure apparatus and method to expose an object with an illumination beam
irradiated on a mask from a light source disposes an optical unit between the light
source and an optical integrator of an illumination optical system to illuminate
the mask with an illumination beam, of which an intensity distribution on a Fourier
transform plane with respect to a pattern on the mask has an increased intensity
portion apart from the optical axis relative to a portion of the intensity distribution
on the optical axis.