Research On Temperature. Measurement Technology Of Infrared Focal Plane Thermal Imager

The infrared temperature measurement technology is the most advanced non-contact temperature measurement technology developed in recent decades. Through this technology, the temperature change on object surface can by reflected through the infrared ray emitted from object, thus it’s has relative great advantage compared to the traditional temperature measurement technologies. In this thesis, based on the infrared thermal lighting equipment and advanced digital signal processing equipment provided in our laboratory, we discuss the infrared temperature measurement function, apply it to the rescue work in fire fighting field, which has great theoretical and realistic significance.In this thesis, we will firstly discuss the basic principle of infrared temperature measurement technology, introduce the theoretical basis for infrared temperature measurement technologies:blackbody radiation law, and deduce the relationship between object temperature and infrared radiation intensity through formula. Then we will introduce two mathematical modeling methods for infrared temperature measurement technology:the mathematical model based on the calibration constant and the mathematical model based on the reference temperature that we will adopt in this system. In the last section of this chapter, we will introduce the temperature measurement calibration method of least square method, including the principle for curve-fitting through least square method, which will processed in Chapter6Experimental Data.Second, we will introduce the construction of hardware platform of infrared temperature measurement system, which mainly includes the following models:first, LVDS signal switching and processing model. This part is mainly used for to switch the LVDS signal outputted from the thermal imaging system into TTL signal to facilitate the subsequent digital signal processing. Second, the FPGA image single primary processing model, this model will receive the TTL signal outputted from the LVDS signal switching model and primarily process the signal to prepare for the nest ARM processing. Last, the man-machine interaction model, in this part, we adopt the duel core processor as the core processing unit to process the outputted digital video signal, receive the signal outputted by the user and indicate the temperature at relevant point. In this chapter, we specially introduce the concrete processing procedure of the hardware platform from the principle and introduce the process in detail, in the last of this chapter, we will introduce the type selection of blackbody furnace and the infrared thermal imaging system adopted in this system, then construct the hardware platform to prepare for the further software arrangement.Third, we will introduce the software framework of the infrared temperature measurement technology. To enhance the transportability and reusability of the software, we will adopt the Linux operating system, which has developed into an rather strong and stable operating system through over20years of development at present. It supports multi-user, multi-process, multithreading and the real-time performance has constantly improved. In this thesis, we will relevant introduce the transplantation of embedded Linux operating system, the compilation of I/O port driver and the fulfillment of key technologies of application program.Last, we will introduce the method to obtain the temperature measurement curve, the experimental procedures and obtained data in detail. The data obtained in the experiment will be fitted into the most proper curve through Matlab software and least square method and this curve will be imputed into the embedded system for the switching from grayscale to temperature.