Abstract: In the electromagnetic calorimeter,longitude light collection uniformity of crystal scintillator has certain influence on the energy resolution.Monte Carlo (MC) method (using Litrani software package) is used to simulate the process of light transmission and collection in the long lead tungstate (PbWO₄ or PWO) crystal.Discussion focused on the influence of the absorption length and the face management on the light collection is presented.And comparison between anisotropic simulation and isotropic simulation is made.

Key words: lead tungstate crystal, light collection, anisotropic medium, absorption length, face management