In order to achieve high accuracy, sensitivity, and high-temperature stability in dusty working environments, magnetometers become a top-priority option in the industrial field. By detecting the change in magnetic flux caused by the displacement of the slide rail during the operation, the magnetometers then measure the movement distance of the slide rail for the next turn. Features such as high-temperature stability, self-temperature calibration, and high-accuracy data the product provides substantially enhance the working efficiency.