| 摘要 |
PURPOSE:To improve the measuring sensitivity and the measuring system, by disposing two electrode plates opposing to an object to be measured and detecting a high frequency current flowing between the electrode plates as electric charges. CONSTITUTION:A detector 5 consists of electrode plates 1, 2, a shield case 3, and a shield plate 4 and is disposed opposingly to an object 20 to be measured. A high frequency oscillator 10 is connected to the electrode plate 2 and a coil 30 is connected to the plate 1. A voltage corresponding to the amount of change of a distance (l) between the detector 5 and the object 20 is produced in the coil 30 to obtain an output voltage/current proportional to the distance (l) with a linearizer 24 via an amplifier 21, a filter 22 and a detection amplifier 23. Since the distance (l) is measured by using the resonance phenomenon of RLC, the measuring sensitivity can be improved and the measuring distance can be taken larger. |
