One embodiment provides a technique of adjusting a gate voltage to be applied to at least one MOS capacitor and an amount of electric charge to be stored in the MOS capacitor so as to determine sensitivity of a change in the amount of electric charge stored in the MOS capacitor, and exposing the MOS capacitor to an electric field for a predetermined amount of time and then reading an electron inflow or outflow result due to the electric field so as to interpret the intensity and the direction of the electric field, thereby measuring the intensity and the direction of the electric field.