Air bearing guideway systems in all axes ensure wear-free operation and optimal guide characteristics in the LH Gantry.The same thermal performance in all axes is guaranteed by means of a base plate, bridge and Z ram made of dark grantie. The rigid construction together with the dual drive of the Y-axis also guarantees the best possible dynamics shile maintaining stability. In summary the machine frame forms an inherently stable, homogeneous unit with can be configured to special size and accessoried which active dampening on line temperature compensation and high resolution optical scales.