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Abstract. The energy range above 60 keV is important for the study of many open problems inhigh energy astrophysics such as the role of Inverse Compton with respect to synchrotron or thermal processes in GRBs, non thermal mechanisms in SNR, the study of the high energy cut-offs in AGN spectra, and the detection of nuclear and annihilation lines. Recently the development of high energy Laue lenses with broad energy bandpasses from 60 to 600 keV have been proposed for a Hard X ray focusing Telescope (HAXTEL) in order to study the X-ray continuum of celestial sources. The required focal plane detector should have high detection efficiency over the entire operative range, a spatial resolution of about 1 mm, an energy resolution of a few keV at 500 keV and a sensitivity to linear polarization. We describe a possible configuration of the focal plane detector based on several CdTe/CZT pixelated layers stacked together to achieve the required detection efficiency at high energy. Each layer can operate both as a separate position sensitive detector and polarimeter or work with other layers to increase the overall photopeak efficiency.Each layer has a hexagonal shape in order to minimize the detector surface required to cover the lens field of view. The pixels would have the same geometry so as to provide the best coupling with the lens point spread function and to increase the symmetry for polarimetric studies. Laue lenses for high energy X-RaysThe energy band > 60 keV is of key importance in the study the radiation emission mechanisms of the celestial sources, their nature, their evolution with time and their contribution to the Cosmic X-ray Background (CXB). The development of focusing optics at these energies is necessary to increase the statistical quality of the high energy spectra of weak celestial sources. Recently high energy Laue lenses [Von Ballmoos P. and Smither R. K., 1994;Pisa et al., 2005] with broad energy band-passes from 60 to 600 keV have been proposed for use in a Hard X ray focusing Telescope (HAXTEL): a multi-lens configuration appears the most efficient and compact solution. To extend the telescope band-pass to lower energies, multilayer optics and/or coded mask telescopes, depending on the science goals, can complement the lenses.