Temperature distribution measurement based on ML-EM using square type ultrasonic CT system

In this paper, a measurement method for cross-sectional temperature distributions is considered. A novel method based on an acoustic computed tomography (CT) technique is proposed. Specifically, the temperature distributions are estimated using the time of flight (ToF) of multidirectional ultrasonic propagation paths. Maximum Likelihood - Expectation Maximization (ML-EM) method and the Median Filter are introduced to reconstruct the temperature distributions in a square area properly. The effectiveness of the proposed reconstruction method is confirmed experimentally.