Temperature measurement is a critical variable for microwave power control and recipe conformance. A preliminary comparison between an IR detector and a fiberoptic measurement also showed similar differences. However, those tests were conducted under atmospheric pressure. The discrepancy may be attributed to the fogging effect on the IR detector in the presence of steam. Nevertheless, it does raise concerns as to how reliably the IR detector measures under a vacuum.
Infrared technology allows temperature sensing from a distance.
However, it can be error-prone if not carefully calibrated or focused appropriately. The best available technology is fiberoptic probes. Following are brief descriptions of these two technologies. However, an IR detector has certain limitations. Only surface temperature is measured, and the correlation with internal temperature may be difficult to determine, particularly in the presence of berry skin or protective membranes.