Multiple Sensor Optical Thermometry System for Application in Clinical Hyperthermia

The thermometry system described is based upon the temperature dependence of the band edge absorption of infrared light in GaAs crystal. The design of the thermometry was completed, and the system was subjected to an extensive evaluation, including testing with tissue phantoms and microwave applicators. The system has up to 12 temperature sensors which are packaged in two basic probe coinfigurations: a single-sensor probe with a length of 1.2 m and a diameter of 0.6 mm; and a four-sensor linear array probe with a length of 1.2 m, diameter of 1.1 mm, and spacing of 1.5 cm between adjacent sensors. Results of thermometry evaluation are presented, including data on automatic calibration, temperature accuracy and stability, and EMI protection.