抄録
In this paper, discrimination of material and detection of the thickness and distance between the sensor and the material are presented by the proposed sensor. The proposed sensor uses a pair of CdS cells as the electrodes of the plane type capacitance sensor and measures capacitance by changing the strength of emission of the light emitting diode (LED). Several capacitance values are obtained by the proposed sensor because the resistance of CdS changes. Accordingly, the optical and electrical properties of the object are obtained from capacitance values. In this experiment, discrimination of two kinds of sample materials and detection of the thickness and distance between the sensor and the material were demonstrated by the proposed sensor. As a result, it was suggested that discrimination of insulating and conductive materials including detection of the thickness between 2 mm and 10 mm and the distance between 1 mm and 4 mm were possible by the proposed sensor.
