This paper discusses the technical progress to date in 157 nm full field scanners, which are in the process of final tuning. The high NA projection optics was designed to meet accelerating demands for smaller geometries. A catadioptric system with a line-selected laser was chosen to solve the problem of chromatic aberrations. Wavefront aberration of the catadioptric system was measured using a 157 nm PMI, based on which the projection optics has been tuned up to achieve the target performance. The exposure results show that 60 nm L&S were resolved in accordance with λ/NA improvement, demonstrating the basic potentials of 157 nm lithography. CD uniformity within the wafer is comparable to KrF and ArF systems while the purge system, the main body, and the resist process have been confirmed to be stable. When compared to ArF, local flare increases significantly. However, it has been confirmed that local flare can be greatly mitigated by improving lens surface accuracy. Further reduction in local flare, needed for commercialization of 157 nm tools, is expected to be achieved by extending the current improvement as the CaF2 performance has rapidly approached next generation specifications over the past year.