All infrared thermometers must know the room temperature, and so all manufacturers suggest to wait for a certain time (usually from 10 to 30 minutes or more depending on the difference of the temperature) before using the thermometer when you come from another room at a different temperature then the room where the thermometer is used. With Thermofocus, you do not need for waiting, thanks to 2 exclusives patented systems for quick stabilization: the AQCS and the MQCS.