Anderhub, H.Backes, M.Biland, A.Boller, A.Braun, I.Bretz, T.Commichau, S.Commichau, V.Domke, M.Dorner, D.Gendotti, A.Grimm, O.Hildebrand, D.Horisberger, U.Köhne, J.-H.Krähenbühl, T.Kranich, D.Krumm, B.Lorenz, E.Lustermann, W.Mannheim, K.Neise, D.Pauss, F.Renker, D.Rhode, W.Ribordy, M.Rissi, M.Röser, U.Stark, L. S.Stucki, J.-P.Tibolla, O.Viertel, G.Vogler, P.von Gunten, H.Warda, K.Weitzela, Q.2012-03-052012-03-052011-01-01http://hdl.handle.net/2003/2937110.17877/DE290R-4294Geiger-mode Avalanche Photodiodes (G-APD) bear the potential to significantly improve the sensitivity of Imaging Air Cherenkov Telescopes (IACT). We are currently building the First G-APD Cherenkov Telescope (FACT) by refurbishing an old IACT with a mirror area of 9.5 square meters and are constructing a new, fine-pixelized camera using novel G-APDs. The main goal is to evaluate the performance of a complete system by observing very high energy gamma-rays from the Crab Nebula. This is an important field test to check the feasibility of G-APD-based cameras to replace at some time the PMT-based cameras of planned future IACTs like AGIS and CTA. In this article, we present the basic design of such a camera as well as some important details.enElsevierNuclear Instruments and Methods in Physics Research A ; Volume 639, Issue 1Cherenkov telescopeGeiger-mode avalanche photodiode (G-APD)ground-based gamma-ray astronomyinstrumentation004article (journal)