New Developments in Linear Colliders Final Focus Systems
  The length, complexity and cost of the present Final Focus designs for linear colliders grows very quickly with the beam energy. In the paper, a novel final focus system is presented and compared with the one proposed for NLC. This new design is simpler, shorter and cheaper, with comparable bandwidth, tolerances and tunability. Moreover, the length scales slower than linearly with energy allowing for a more flexible design which is applicable over a much larger energy range. 
P.Raimondi, A. Seryi