Reflection and refraction optical system and projection exposure apparatus using the same

A projection exposure apparatus comprising:

• an illumination system for illuminating an original with light from an excimer laser, the excimer laser providing light having a wavelength less than 300 nm;
• and
• a projection optical system for projecting a pattern of the original onto a substrate, the projection optical system including:
• (i) a polarization beam splitter;
• (ii) a quarter waveplate;
• (iii) a reflection mirror;
• and
• (iv) polarization plane changing means comprising a rotatable half waveplate,
• wherein a beam from the original is projected by way of said polarization beam splitter and of said quarter waveplate upon said reflection mirror, wherein the projected beam is reflected by said reflection mirror and is projected by way of said quarter waveplate and said polarization beam splitter upon the substrate, and wherein said polarization plane changing means is disposed between said polarization beam splitter and the substrate to change the plane of polarization of the beam from said beam splitter.