Opacity Sensor Based on Photovoltaic Effect of Ferroelectric PLZT Ceramic With Pt Wire Implant

This work reports the formation of a ferroelectric poled bulk ceramic structure as opacity sensor (OPS) and the improved photovoltaic output of the lead lanthanum zirconate titanate (PLZT) employed. This ceramic was implanted during its fabrication with a platinum wire (Pt-wire) which works as an internal electrode. Photovoltaic current have been measured in PLZT with Pt-wire under chopped LASER beam illumination. This photovoltaic current was measured on the upper face of a sensor in order to obtain a characterization curve. Different thin materials were put on the OPS in order to determine its opacity according to their thickness and viscosity. Opacity is a condition in which a material partially or completely impedes the passage of light beam. The results indicated that the photovoltaic current response was less than 700 pA at 160 mW/cm² maximum power of illumination; 2-D scans were obtained from fruit tissues, vegetal oils and thin materials at 160 mW/cm² of illumination in order to get a representation of opacity images.