The difference between the digital thermometer and pointer thermometer

Digital thermometer USES the temperature sensitive element is the temperature sensor ( Such as platinum resistance, thermocouple, semiconductor, thermistor, etc. ) Would change, the change of temperature into electrical signals, the electrical signal can be used in adc circuit that AD conversion circuit converts analog signals to digital signals, the digital signal to send to processing unit, processing unit through internal software calculation will be linked to the digital signal and temperature, temperature can be displayed value, and then through the display unit, display observation to the person. And pointer thermometer is around into threaded thermal bimetallic strip as thermal devices, and put it in a protective sleeve tube, one end is fixed, known as the fixed end, on the other end of the connection in a thin axis, become a free end. Spool at the free end is equipped with a pointer. When the temperature changes, the resulting thermal devices the free end of the rotation, drive the thin axis from the Angle of the pointer changes, the corresponding temperature indicator on the dial; Straight table by steering transmission mechanism drive the pointer changes.