Patent ID: 6762050
Filing Date: 2004-07-13
Classification: B01J,B41J,C12Q,C40B,G01N

Abstract:
A sensor device comprising:a substrate; resistance sensors formed on the substrate, each of the resistance sensors comprising: (a) a pair of electrodes; and (b) an electro-conductive polymer deposited on and between the pair of electrodes, wherein the electro-conductive polymer absorbs aromatic molecules and changes an electrical resistance by absorbing the aromatic molecules inside the electro-conducting polymer; and a transducer circuit for transducing the change in the electrical resistance of the electro-conductive polymer into an electric signal, each of the transducer circuits comprising: (a) a source of electric current electrically connected to the resistance sensor; (b) a source of an offset voltage; (c) a differential amplifier electrically connected to the resistance sensor, the differential amplifier outputting a difference between a voltage provided with the resistance sensor and the offset voltage; and (d) a high-gain amplifier that amplifies a voltage output from the differential output, wherein the source of electric current, the source of the offset voltage, the differential amplifier, and the high-gain amplifier comprise thin-film transistors; and the electro-conductive polymer includes at least one of polypyrrol, polymethylpyrrol, polythiophen, polymethylthiophen, polyaniline, and polyphenylene vinylene.