APPARATUS AND METHOD FOR BARRIER LAYER EXISTENCE DETERMINATION USING FLUORESCENCE MEASUREMENTS

摘要

A fabrication method is provided for forming a multilayer preform with a barrier layer and determining the existence of the barrier layer in the multilayer preform. The barrier layer may consist essentially of a polymeric material without any optical brighteners. The multilayer preform may be illuminated with ultra-violet (UV) light. The fluorescence caused by the interaction of the UV light with the multilayer preform may be measured to generate a fluorescence signal. Based on the fluorescence signal, the existence of the barrier layer in the multilayer preform may be determined.