Abstract: A pollen sensor and method for detecting pollen which discriminates pollen particles floating in air from other particles on a real time basis. The pollen sensor includes an illumination position for generating a light beam, a first receiver for measuring the intensity (I) or (Ip) of a light beam scattered by floating particles in a detection zone, a second receiver for measuring the intensity (Is) of a polarized light beam in a direction perpendicular to light illuminated by the light beam and means for measuring the degree of polarization of the particles for distinguishing pollen particles from other particles.

Abstract: A gas sensor includes a pair of electrodes printed on an electrically insulating substrate, a sensitive layer deposited on tip portions of the electrodes and a part of the substrate adjacent to the tip portions and bridging the space between the electrodes at the tip portion, and a protective film deposited on the electrodes and a part of the substrate adjacent to the tip portion so that a part of each electrode covered with the sensitive layer is free of the protective film. The sensitive layer is formed by depositing titanium oxide by plasma spraying on the substrate, and then heat-treating the deposited titanium oxide, so as to provide a diffusion reactive layer between the sensitive layer and the substrate and to form fine grooves on the surface of the sensitive layer.

Abstract: A humidity sensor as well as a humidity detection circuit are disclosed, the former employing a humidity sensitive material the electric resistance of which varies in response to the variance of humidity in an atmosphere and the latter employing such humidity sensitive material. The humidity sensor comprises a base plate made of alumina or the like with a humidity sensitive material formed on the base plate so as to form a film of a high molecular polymer unit which contains a reactive cationic monomer unit, is capable of detecting humidity over a wide range, shows little variance in nature in a high humidity atmosphere of organic gas, and has a long life. The humidity detection circuit comprises an oscillation circuit, a pair of electrodes which are connected by means of the humidity snesor and to one of which is supplied the output of the oscillation circuit as an input, and an amplifier circuit which is connected to the other one of the pair of electrodes.

Abstract: A humidity sensor as well as a humidity detection circuit are disclosed, the former employing a humidity sensitive material the electric resistance of which varies in response to the variance of humidity in an atmosphere and the latter employing such humidity sensitive material. The humidity sensor comprises a base plate made of aluminum or the like with a humidity sensitive material formed on the base plate so as to form a film of a high molecular polymer unit which contains a reactive cationic monomer unit, is capable of detecting humidity over a wide range shows little variance in nature in a high humidity atmosphere of organic gas, and has a long life. The humidity detection circuit comprises an oscillation circuit, a pair of electrodes which are connected by means of the humidity sensor and to one of which is supplied the output of the oscillation circuit as an input, and an amplifier circuit which is connected to the other one of the pair of electrodes.

Abstract: A sensor having an n-type oxide semiconductor layer and a p-type oxide semiconductor layer spaced from and electrically connected in series with each other and two fixed resistors connected in series with each other, wherein the two semiconductor layers and two resistors are connected to construct a four-arm bridge.