The measurement apparatus for capacitive membrane sensor using mechanical resonance characteristics of membrane and the method thereof

摘要

The present invention relates to a measuring apparatus and method for a capacitor type membrane sensor using a mechanical resonance characteristic of a membrane, and more particularly, to a membrane sensor for detecting a change in a capacitance of the membrane, an AC signal (AC voltage or current The present invention relates to a device for measuring capacitance of a membrane type sensor using a mechanical resonance characteristic of a membrane according to the present invention, and more particularly, to a device and a method for increasing a measurement accuracy of a capacitor type membrane sensor by maximizing a displacement of a sensing electrode by applying a direct current An AC signal having a mechanical resonance frequency of a magnitude sufficient to vibrate the sensing electrode of the membrane sensor can be obtained by using the principle that the membrane has a mechanical resonance frequency equal to the mechanical resonance frequency of the membrane, After applying to the membrane sensor, The change in the mass of the sensing electrode is measured using the change in the mechanical resonance frequency or the coefficient of performance (Q-factor) of the sensing electrode depending on whether or not the sensing material applied to the electrode is reacted with the specific substance, A signal supplying means for supplying an AC signal having a mechanical resonance frequency of a sensing electrode to a condenser type membrane sensor or supplying an AC signal containing a DC component to the sensing electrode; A condenser type membrane sensor in which the mass of the sensing electrode is changed by the reaction of the substance to change the capacitance of the condenser or the capacitance of the condenser is changed by the pressure applied to the sensing electrode, A signal measuring unit for measuring the signal supplied from the signal supply unit, And a frequency spectrum for displaying frequency-dependent signal intensity using the digital value output from the signal measuring unit. Thus, when the sensing electrode of the capacitor-type membrane sensor reacts with a specific substance, And a control and signal processing means for measuring a mass of a specific substance reacted with the sensing electrode or a pressure applied to the sensing electrode using a change in mechanical resonance frequency or Q-factor when the sensing electrode is not used. According to the present invention having such a configuration, it is possible to more precisely measure the mass change of the sensing electrode or the pressure applied to the sensing electrode, dramatically reduce the parasitic capacitor effect of the membrane sensor, It can be analyzed.