The next generation of major US X-ray missions has a default goal to get an effective area at least 10 times larger than the Chandra X-ray Observatory (CXO), a similar angular resolution (i.e., <1 arc-second), and lower cost and mass per effective area. The effective area of the Chandra High Resolution X-ray Mirror Assembly (CHXMA) was, however, about 400 cm2 and the effective area per unit mass was about 0.5 cm2/kg. Thus, a boost of about 10 times in area requires so much costly smooth (<0.5 nm) surface as to require a replication process to bring down the mirror fabrication cost. Furthermore, the low ratio of effective area to mass of the CHXMA translates into an unacceptably high launch cost, even if the fabrication costs for Chandra-like mirrors could be reduced significantly. Hence, thin and lightweight replicated optics are called for. However, as the mirror quality of replicated mirrors may be less than desired, post fabrication processes have been explored to correct the mirror figure in order to bring the mirror quality to within specifications of figure accuracy and mass/unit area. These post fabrication processes have included the use of piezoelectric materials, magnetic smart materials (MSMs) and ion implantation.
USPTO Backgrounds
USPTO Backgrounds