[en] A light ion focal plane detector of 1.2 m length using single wire proportional detectors and cathode readout is described. Focal plane reconstruction and vertical position determination is achieved. Good background reduction and 0.6 mm FWHM detector resolution has been obtained with standard electronic setup. In operation with the spectrograph a 2.7 keV linewidth has been observed for elastic scattering of 20 MeV deuterons from a 50 μg/cm² Au-strip target, 0.5 mm wide. (orig.)