Temperature Field Optical Detection and Reconstruction: Methods, Principles and Applications

ABSTRACT The temperature field constitutes a core parameter for thermal‐process analysis and equipment optimization. Traditional contact‐based temperature‐field measurement techniques suffer from flow‐field interference and single‐point‐detection limitations and cannot satisfy high‐precision measurement requirements within complex high‐temperature environments. This paper systematically reviews the physical principles, detection methods, and reconstruction algorithms of non‐contact optical temperature measurement and temperature field reconstruction. The physical principles include radiation temperature measurement, passive spectral temperature measurement, interference deflection temperature measurement, and optical fiber temperature measurement. The detection methods are divided into passive radiation detection and active laser illumination detection, and their system architectures and application scenarios are analyzed respectively. Optical fiber temperature measurement is classified as contact‐based optical measurement due to the need for physical connection or thermal coupling with the measured object, serving as a supplement to noncontact technologies. The reconstruction algorithms are summarized from classical analytical methods to iterative regularization methods. Finally, issues such as the contradiction of spatial and temporal resolution, multi‐source interference, and the trade‐off between 3D reconstruction accuracy and real‐time performance are discussed, and future development trends are presented, including multimodal fusion, AI‐driven end‐to‐end reconstruction, and system integration.