Infrared Imaging Systems for Human Fever Screening
Studies have shown that there is a correlation between internal core temperature and facial skin temperature. The maximum temperature measured between the eyes usually provides the best correlation with Internal Core Temperature for the following reasons:
- The ophthalmic artery is located in this area and provides increased blood flow, and heat transfer, to the skin surface.
- The lachrymal duct provides a thermally conductive path to deeper, warmer, tissue.
- The skin is thin in this area, decreasing the skin’s insulating affect.
- The inside corners of the eyes are inset and are less affected by the ambient environment.
Due to the skin’s insulating affect and the difference between internal core and ambient air temperature, the temperature measured between the eyes is lower than internal core temperature. The software settings used to estimate this difference is called skin offset (see figure below).
The difference between facial skin temperature and internal core temperature depends on many factors, however in many cases it depends primarily on the ambient air temperature to which subjects have most recently been exposed. Higher ambient temperatures result in higher facial skin temperature that is closer to internal core temperature. Lower ambient temperatures result in lower facial skin temperature.
This product is currently for export only. Optotherm is currently undergoing the US FDA Premarket Notification (510k) submission process for medical devices. As soon as Thermoscreen has been cleared, this product will be available for purchase in the US.