Bean, S.J. De Andrade, V. Deriy, A. Fezzaa, K. Graber, T. Matus, J. Preissner, C.A. Shu, D. JACoW Publishing Geneva, Switzerland 2673-5520 978-3-95450-229-5 10.18429/JACoW-MEDSI2020-TUPC15 English 211-214 focusing optics synchrotron photon interface Contribution to a conference proceedings 2021 2021-10 https://doi.org/10.18429/JACoW-MEDSI2020-TUPC15 https://jacow.org/medsi2020/papers/tupc15.pdf A new nano-computed tomography projection microscope (n-CT) is being designed as part the Advanced Photon Source Upgrade (APS-U) beamline enhancement at sector 32-ID. The n-CT will take advantage of the APS-U source and provide new capabilities to the imaging program at 32-ID. A Kirkpatrick and Baez (KB) mirror-based nanofocusing optics [1,2] will be implemented in this design. To meet the n-CT imaging goals, it is the desire to have sub 10 nanometer vibrational and thermal drift stability over 10-minute measurement durations between the optic and the sample. In addition to the stability requirements, it is desired to have a variable length sample projection axis of up to 450 mm. Such stability and motion requirements are challenging to accomplish simultaneously due to performance limitations of traditional motion mechanics and present a significant engineering challenge. To overcome these limitations, the proposed n-CT design incorporates granite air bearing concepts initially used in the Velociprobe [3]. These types of granite stages have been incorporated into many designs at APS [4] and at other synchrotron facilities [5]. Utilizing the granite air bearing concept, in tandem with other design aspects in the instrument, the requirements become reachable. A novel multi-degree of freedom wedge configuration is also incorporated to overcome space limitations. The design of this instrument is described in this paper.