Method and apparatus for measuring internal body temperature utilizing infrared emissions

摘要

A hand held probe unit has an infrared sensitive thermopile mounted in a metal housing kept at a constant reference temperature by a regulator circuit. A waveguide tube, surrounded by a thermally insulative probe, directs infrared emissions to the thermopile. The thermopile and regulator circuit of the probe unit are electrically connected to processing circuitry in a chopper unit. Prior to taking a patient's temperature, the probe unit is mated with the chopper unit so that the thermopile detects infrared emissions from a reference target which is also kept at a constant reference temperature by another regulator circuit. The processing circuitry repeatedly acquires the output level of the thermopile and stores calibration data. The probe unit is then removed from the chopper unit, the probe is covered with an IR transparent, disposable speculum, and is inserted in the patient's external ear canal. The processing circuitry then determines the patient's core temperature by comparing the stored calibration data to the maximum output of the thermopile during a succession of ear canal samplings.