Schemes for Segmenting the Main Reflector of the FAST

Acting as a pilot of the Square Kilometer Array(SKA), a Five-hundred-meter Aperture Spherical Telescope(FAST)project puts forward many innovative ideas, among which the design of the active main ref lect r shows fascinating potential.The main spherical reflector is to be composed of thousands of small spherical panels, which can be adjusted to fit a paraboloid of revolution in real time.For the construction and performance, the rms of the fit must be optimized, and so appropriate dimensional limits for the panels need to be determined.The issue of how to divide the spherical reflector mathematically is addressed in this paper.The advantages and drawbacks of various segmenting methods are discussed and an optimum one is suggested.