With the rapid development of extreme ultraviolet (EUV) light sources, such as plasma-based light source and FreeElectron Laser (FEL), it provides unprecedented powerful ultra-short EUV radiations. These extremely high intenseultra-short pulses of radiation bring great challenges to the optical components utilized for steering these light beams,especially the radiation damage issues. However, more studies on the EUV damage mechanisms on optical materials arestill quite desired because of limited beamtime provided by FEL facilities.In this study, we present a table-top focused EUV optical system built at the Institute of Precision Optical Engineering(IPOE) for performing EUV damage tests on optical materials. This setup consists of a laser-plasma light source, amodified Schwarzschild objective and an EUV energy attenuator. With a large numerical aperture of 0.44 and ademagnification of 11, the Schwarzschild objective is composed of two annular spherical mirrors coated with Mo/Simultilayers. By using the Zirconium filter and Mo/Si multilayers, this setup can generate the focused radiation with anenergy density of 2.27 J/cm~2 at the wavelength of 13.5 nm on the image plane of the objective with ～8.3 ns pulseduration. The EUV energy can be changed using a gas attenuator by varying the gas pressure of Helium or Nitrogeninside the chamber. The performance and potentials of this setup are demonstrated by the single-shot or multi-shotdamage tests on some samples, such as Au thin film, CaF_2 and Mo/Si multilayer mirror. The damage thresholds weredetermined and the possible damage mechanisms are discussed together with available experimental results.
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