Sensor sensitivity and resolution

Date:2021-09-15 00:00

  sensor sensitivity

  Sensitivity refers to the ratio of the output change △y to the input change △x under the steady state working condition of the sensor. It is the slope of the output-input characteristic curve. If there is a linear relationship between the sensor output and the input, the sensitivity S is a constant. Otherwise, it will vary with the amount of input. The dimension of sensitivity is the ratio of the dimensions of output and input. For example, for a displacement sensor, when the displacement changes by 1mm, the output voltage changes by 200mV, then its sensitivity should be expressed as 200mV/mm. When the dimensions of the output and input of the sensor are the same, the sensitivity can be understood as the magnification. Improve the sensitivity, can get higher measurement accuracy. However, the higher the sensitivity, the narrower the measurement range and the worse the stability.

  the resolution of the sensor

  Resolution refers to the ability of a sensor to perceive the smallest change in the measurand. That is, if the input quantity changes slowly from some non-zero value. When the input change value does not exceed a certain value, the output of the sensor will not change, that is, the sensor cannot distinguish the change of the input quantity. Its output changes only when the input quantity changes by more than the resolution. Usually the resolution of each point in the full-scale range of the sensor is not the same, so the maximum change value in the input quantity that can produce a step change in the output quantity in the full-scale range is often used as an index to measure the resolution. If the above indicators are expressed as a percentage of full scale, it is called resolution. Resolution has a negative correlation with the stability of the sensor.