An optical system for the generation of a beam with a variable and controllable polarization status has been designed,
realized and tested. The system is based on an interferometric set up, consisting of a splitting system, a phase delay
system and a recombination system. By controlling the optical path, it is possible to obtain every polarization status:
linear, elliptical and circular. The system can be realized with an all reflective scheme and it can work in a wide spectral
band of the electromagnetic spectrum, from the near-infrared down to the extreme ultraviolet. The system can be
integrated in different optical setups in order to enhance their versatility, such as in laser devices, optical
instrumentations, synchrotron lines or free electron lasers beam transport system. Finally it can be also used to test
optical device and for calibration of optical components.