Development of the preshower detector prototypes for LHCb experiment

We present results of the development and experimental study of the preshower detector prototypes for LHCb experiment in the test beam of SPS accelerator (CERN). The preshower detector consists of two identical layers of scintillator pads and a layer of lead converter in between. The light from pads is readout by means of wave-length shifting fiber coiled and glued inside a circular groove in the scintillator body. The study of prototypes allowed performing an optimal choice of the light collection and mechanical design of the preshower detector modules.