US Patent 7423740 Reticle and optical characteristic measuring method

A reticle having a test pattern for measurement of an optical characteristic of a projection optical system has a pattern adapted so that a high frequency component of a spectrum at a pupil plane of the projection optical system is reduced or suppressed. Illumination light is projected to the test pattern of the reticle in one direction or plural directions, and positions of images of the test pattern, formed by the projections in the plural directions, are detected and, based thereon, the optical characteristic of the projection optical system is measured.