A Test of Bell’s Inequality with Spacelike Separation

This is a description of the experimental apparatus and methods used for a long‐distance test of Bell’s inequality, whose main results were published in G. Weihs, T. Jennewein, C. Simon, H.Weinfurter, and A. Zeilinger, Phys. Rev. Lett. 81, 5039 (1998). A brief discussion of recent attempts at analyzing our measurement data is included.