METROLOGY SYSTEM, AND APPARATUS INCLUDING PRIMARY MIRROR

A metrology system measures an amount of displacement of a structure of apparatus including primary mirror, the apparatus including primary mirror including a primary mirror portion including a primary mirror and a primary mirror supporting portion, an elevation axis structural body supporting the primary mirror portion, and being rotatable around an elevation axis, an azimuth mount being rotatable around an azimuth axis allowing an azimuth angle in the orientation direction to be changed, and to support the elevation axis structural body, and a pedestal portion supporting the azimuth mount, and the metrology system includes an elevation axis base portion provided along the elevation axis, passing through a position where the elevation axis and the azimuth axis intersect, and being fixed to the azimuth mount, and an inclinometer that is disposed at a position of the elevation axis base portion through which the azimuth axis passes and measures an inclination angle.