How does a digital thermometer work?

You might have felt that mercury thermometer is being replaced by a digital thermometer at clinics and hospitals.

Digital Thermometer

It is due to the ease of taking a reading and now it is common to measure temperature with electronics.

"The most common sensor used in the digital thermometer is thermoresistor (or thermistor)"

How it works?

Digital thermometers use a thermistor (inside the tip ). which is temperature-sensitive. This sensor changes its resistance with changes in temperature. A computer or other circuit measures the resistance and converts it to a temperature to display.

• They are equipped with beep alarm& memory function.
• Can read temperature between 94°F and 105°F (35°C and 42°C).
• The battery used to power the thermometer is called a button cell (LR41).

Tip of Thermometer

The tip is said as the heart of the thermometer as a thermistor is equipped in this tip which is responsible for converting the physical temperature into electrical signals.