薄膜电容湿度传感器工作原理：Water vapour penetrates the upper electrode and reaches the active polymer film. 水蒸汽穿过上部电极 , 到达活性聚合物薄膜。

How much water vapour is absorbed into the film depends on the ambient relative humidity. 多少水蒸汽被薄膜吸收取决于周围环境的相对湿度。

Because the sensor is small and the polymer film thin , the sensor responds quickly to changes in ambient humidity. 因为传 感器尺寸小和聚合物薄膜很薄，所以传感器可以对周围环境的湿度变化作出快速反应。

The water vapor absorbed in the film changes the dielectric properties of the sensor: the capacitance of the sensor changes. 聚合物中吸收的水蒸汽 改变了传感器的电介质特性 ：传感器的电容值改变。 The change in the sensor's capacitance is measured with measurement electronics . 传感器电容的改变通过测量电路来测量。