Answer: if it is used for the first time, please follow the following steps:

Step 1: place the thermometer in a stable ambient temperature for more than 30 minutes;

Step 2: use a traditional mercury thermometer or electronic thermometer to measure someone, assuming a temperature of 36.8 degrees Celsius;

Step 3: use a non-contact infrared thermometer to measure the same person. Pay attention to the measurement distance and measurement method: keep the distance between the thermometer and the forehead between 1-3cm, and remove any obstacles that may affect the measurement, such as hair and sweat. If the same temperature is 36.8 ℃, the thermometer is set normally and can be used normally, If you get a lower reading of 36.4 degrees Celsius with a difference of 0.4 degrees Celsius, you can set F1 to "0.4 degrees Celsius". On the contrary, if there is more than 0.4 degrees Celsius, you can set F1 to "- 0.4 degrees Celsius"