# Color CCD High-Temperature Measurement Method Based on Matrix Searching  
[PERSON]  
1 School of Mechanical Engineering, Nanjing University of Science and Technology, Nanjing 210094, China; 1 [EMAIL_ADDRESS] (C.L.)12 School of Mechanical Engineering, Nanjing University of Science and Technology, Nanjing 210094, China; 1 [EMAIL_ADDRESS] (C.  
temperature measurement study based on CCD devices [12]. In this method, the ratio of the thermal radiation signal intensity of two similar wavelength positions is used to eliminate the influence of emissivity, which effectively ensures the accuracy of temperature measurement. However, this method is greatly affected by dual-channel wavelength selection, and the temperature calculation is different in the case of different channel calculations. In addition, the method is combined with Wien approximation and needs to be completed by solving the logarithmic equation of the pixel grayscale so that the accuracy of the solution is affected. Based on this study, in 2010, [PERSON], [PERSON] et al. carried out a three-channel broadband temperature measurement method based on color CCD cameras, which is called spectral color temperature measurement [13]. In this method, the CCD detector based on Bayer color filtering technology is used to collect the thermal radiation signal of RGB three channels to realize temperature inversion. Meanwhile, the measurement performance evaluation is studied, and the measurement method is further improved [14]. This method puts forward a new idea of temperature inversion from chromaticity information, but the linear emissivity model used in the research still cannot meet the application. In recent years, [PERSON], [PERSON] et al. have carried out a three-channel spectral band colorimetric temperature measurement method to neutralize the effect of emissivity [15], [PERSON], [PERSON] et al. combined multispectral temperature measurement with CCD temperature measurement methods and developed a multispectral image temperature measurement method to avoid the influence of calibration parameters and spectral emissivity [16; 17]. However, there are also problems in the study, such as the long solution time and the great influence of the selection of central wavelength on the temperature calculation. It is easy to understand that for the current high-temperature measurement research, the more difficult problem lies in the process of solving and obtaining the emissivity. The main reason is that the solution process cannot meet the closed condition due to the existence of emissivity in the process of solving the inverse temperature problem. The emissivity model that is more complex and in line with the actual situation will increase the difficulty of solving the equation, if the complex algorithm is used, it will increase the amount of calculation, and increase the convergence time [18; 19], and reduce the measurement efficiency. Meanwhile, the nonlinear acquisition effect of the device, i.e., the gamma correction process, is neglected in the above study to reduce the complexity of the solution [20], and the thermal radiation signal absorbed by the transmission medium is ignored, which affects the measurement accuracy to a certain extent.  
In this paper, the study of the color CCD high-temperature measurement method based on the matrix search process is carried out, and the reverse solution process of high-temperature measurement is transformed into a forward mapping matrix search process. By introducing the actual spectral emissivity data, the absorption model of the transmission medium, and the nonlinear acquisition process of equipment, a temperature measurement method that is more in line with the actual temperature measurement is established. The temperature visualization procedure based on the mapping matrix search are designed, and the performances of the solution method under different situations is discussed, which provides a new idea for CCD temperature measurement.