| 摘要 |
PROBLEM TO BE SOLVED: To provide a physical quantity measurement device capable of continuously measuring a desired physical quantity such as viscosity of liquid, in a state in which the environmental resistance is high, the device is stable for a long term, and the influence of temperature variation is small.SOLUTION: The physical quantity measurement device measures a desired physical quantity on the basis of the resonance frequency of a sensor. The physical quantity measurement device includes: a first phase synchronization loop including the sensor; a second phase synchronization loop including the sensor; and an adder for adding an output signal of a voltage-control-type oscillator of the first phase synchronization loop to an output signal of a voltage-control-type oscillator of the second phase synchronization loop. The two phase synchronization loops are operated in parallel.SELECTED DRAWING: Figure 1 |
