This paper reports on the performances of a test prototype mirror, based on the Piezoelectric Bimorph Mirror technology, which has been designed and manufactured (in collaboration with the French optical company SESO) for the national Japanese 8 GeV storage ring SPring-8. The device consists of two 150 mm long modules assembled sideby-side. It exhibits superior surface quality with respect to previously manufactured long piezoelectric bimorph mirrors, as the junctions between modules do not introduce any distortion on the reflecting surface. The mirror can effectively compensate low frequency components of the figure error/waviness left by polishing. Two different simple optimisation methods have been validated: "ex-situ" in the metrology lab (Adaptive Optics correction & control algorithm) and, for the first time, "in-situ" at the beamline (Hartmann test). After optimisation with coherent x-rays at the 1 km long SPring-8 beamline, elliptical shaping was achieved with sub prad level precision for the slope error rms. The associated height error is as small as 8 nm rms. over 200 mm illuminated length. An extremely sharp and gaussian 8 im FWHM wide spot size was obtained by vertically demagnifying the undulator source. It has also been demonstrated that it is possible to bend the mirror to an arbitrary, user-defined, shape; i.e. sinusoidal.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations鈥揷itations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.