To amplify sensors output signal. This becomes critical if the sensor is located far away from the instrumentation or if there is electrical noise that distorts the sensor output. To improve the functionality of temperature measurement. Thin film element is manufactured by using highly sophisticated technology called photolithography. This technology enables sensing element to be more rugged, smaller in size, more accurate, and more cost affective then traditional wire-wound elements.
Element is the component, which actually does the measuring.
Junction is a point where two dissimilar metals are joined. A grounded junction puts the junction in contact with the packaging, protecting, metal case. This allows for a faster response time, however, a grounded tip is susceptible to electromotive forces in the environment, which might cause potential errors in the measurement. An ungrounded junction, therefore, is one without a contact with the metal case. Thus, have slower response time, but is less likely to provide erroneous readings.