LITHOGRAPHY PROJECTION APPARATUS COMPRISING MEASUREMENT SYSTEM WHICH MEASURES PROJECTED SYSTEM TO REFERENCE FRAME AND HAS SENSORS, PREPARATION METHOD OF DEVICE, AND ANGLE ENCODER

PURPOSE: Provided are a lithography projection apparatus which has an improved structure to measure the position of a projection system, a method for preparing a device and an angle encoder which is used to measure the rotation of a projection system with a center of a light axis line. CONSTITUTION: The lithography projection apparatus comprises a radiation source which provides a radiation projected beam; a support structure which supports a patterning means for patterning the projected beam according to a desired pattern; a substrate table which holds the substrate; a projection system which projects the patterned beam on the target region of the substrate; a reference frame; a first measurement system which measures the position and/or displacement of the substrate table to the reference frame; and a second measurement system which measures the position and/or displacement of the projection system to the reference frame, wherein the first measurement system comprises a plurality of first sensors provided with each measuring axis line and located on the reference frame, the second measurement system comprises a plurality of second sensors provided with each measuring axis line and located on the reference frame, and at least one sensor of the second measurement system has measuring axis lines(Sx, Sy, Xz1, Sz2, S_Rz) passing through the invariant point(ip1) of the projection system.