Electronic thermometer and mercury thermometer compared, should be more accurate mercury thermometer. Because the mercury thermometer working principle, is due to the thermal expansion of mercury is proportional to the temperature to work, and mercury is more stable, in the closed thermometer thermal expansion coefficient is constant. Electronic thermometer is through the thermal sensor, the generated thermoelectric potential to discern the temperature level. Since the thermal sensor has the problem of zero-point drift and cold-end compensation, temperature distortion can occur if an electronic thermometer of insufficient grade or quality is used. Clinically, patients are recommended to use mercury thermometers, and only if they cannot find a mercury thermometer will they use an electronic thermometer as a way to take their temperature.