  We report on a reflective wave-plate system utilizing phase-shifting mirrors
(PSM) for a continuous variation of elliptical polarization without changing
the beam position and direction. The scalability of multilayer optics to large
apertures and the suitability for high-intensity broad-bandwidth laser beams
make reflective wave-plates an ideal tool for experiments on relativistic
laser-plasma interaction. Our measurements confirm the preservation of the
pulse duration and spectrum when a 30-fs Ti:Sapphire laser beam passes the
system.
