The temperature may be measured by a thermocouple or a pyrometer.
Pretest temperatures were also taken using a suction pyrometer.
While the pyrometer measures the sample's surface temperature, the interior temperature is the real subject of concern.
Either device must be equipped with an indicating pyrometer which is positioned in the working area at the operator's eye level.
Another temperature monitoring method is to use a contact pyrometer.
Optical pyrometer techniques were eliminated because viewing ports are not typically available.
British Dictionary definitions for pyrometer
an instrument for measuring high temperatures, esp by measuring the brightness (optical pyrometer) or total quantity (radiation pyrometer) of the radiation produced by the source. Other types include the resistance thermometer and the thermocouple