Fully Printable, Flexible, Large Area Organic Optothermal Sensors for Human-Machine-Interfaces
ABSTRACT Pyroelectric sensors presented in this work are based on polymers from the PVDF family which are comprised of a piezo- and/or pyroelectric polymer thin film capacitor, integrated with high performance organic thin film transistors operating at low voltages and acting as impedance converters, signal amplifiers and conditioners. For flexible integration with diverse electronic devices, large area processes applicable for industrial partners such as screen printing have been used for the fabrication of the sensors. With respect to the intended purpose for detection of human body radiation the absorbance of the impinging IR-light is dramatically increased by the application of printed carbon top electrodes, hence meeting the requirements for low-cost large area processability. Here we present good working integrated sensor devices based on two components, being an organic thin film transistor with a high-k-nanocomposite gate dielectric and a PVDF- copolymer based sensor. Besides, the integration of printed electrochemical transistors with printed sensors for large area applications has been realized successfully.
Full-textDOI: · Available from: Martin Zirkl, Jul 01, 2015
- SourceAvailable from: Gerda Buchberger[Show abstract] [Hide abstract]
ABSTRACT: Functional materials such as piezoelectric and pyroelectric polymers or organic photodiodes are promising candidates for flexible sensor surfaces; combining thin films of these materials with large-area resistive electrodes leads to position-sensitivity for passive touch- or light-point localization, respectively. However, this type of large-area sensors for passive stimulus-localization lacks a general theoretical description, which is necessary to understand the physics underlying the sensor concept.To this end we present a one-dimensional, theoretical model for these sensors; the model is based on the solutions of the telegrapher’s equations under the appropriate boundary conditions. We specify the applied boundary conditions, list approximate solutions for certain parameter ranges and present two model-based normalization procedures. These normalization procedures allow for stimulus localization independently of its magnitude and significantly increase the quality of the measurement signals. Experimental results agree well with theoretical findings, proving the suitability of the presented theoretical models.Sensors and Actuators A Physical 02/2013; 202:37-43. DOI:10.1016/j.sna.2013.02.016 · 1.94 Impact Factor
Conference Paper: A Flexible Polymer Sensor for Light Point Localization[Show abstract] [Hide abstract]
ABSTRACT: 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.26th European Conference on Solid-State Transducers, EUROSENSOR 2012, Krakow; 09/2012