A Flexible Polymer Sensor for Light Point Localization

We present a flexible polymer sensor for light point localization based on the pyroelectric polymer poly(vinylidene fluoride) (PVDF) in combination with large area resistive electrodes. This large area sensor is simple in design; a division of the sensor surface into an array of individual sensor elements as used in active matrix technology is avoided. Electronic circuitry is placed only at the edges of the device. We have fabricated a flexible sensor strip with a length of 12 cm and a width of 1.6 cm according to the proposed concept. The position sensitive output signals of the sensor strip have been measured in response to the intensity-modulated light of a red laser diode. Two model-based normalization procedures have been developed in order to increase the quality of the measurement signals. The results indicate that the sensor strip can be treated mathematically analogous to a transmission line. Calculations based on the solutions of the telegrapher's equations under the appropriate boundary conditions are in good agreement with the experimental results, proving the suitability of the proposed concept for position sensitive detection.