Development of a miniature area blackbody source with excellent temperature uniformity based on aluminum substrate

• Developing a miniature area blackbody source with advantages of low cost, simple structure, strong portability. • Integrating an exponential function into the layout of the heating resistor to improve temperature uniformity. • Enhance temperature uniformity of the ROI to less than 0.032°C. Area blackbody as the standard radiation source was essential for calibrating infrared detection device. Temperature uniformity was a key performance index for blackbody, and enhancing temperature uniformity was crucial for increasing the accuracy of infrared detection system. This paper discussed the development of an area blackbody radiation source based on aluminum substrate with the area of φ30 and the temperature range from ambient to 200°C. Unlike others, the blackbody combined the characteristics of low cost, simple structure, strong portability and easy processing in addition to excellent temperature uniformity. Through thermodynamic simulation, we firstly explored how the thickness of the aluminum substrate and the spacing and width of the heating resistor affected the temperature uniformity of the radiation surface. Then a novel layout of heating resistor was proposed to improve temperature uniformity, which for the first time integrated an exponential function into the layout of the resistor. The heating resistor layouts of φ45 and φ60 were also designed and simulated to verify the feasibility of the non-equidistant heating resistor layout. The results demonstrated significant improvements: for the φ30 heating resistor layout, temperature uniformity was completely enhanced to less than 0.032°C; Similarly, temperature uniformity of φ45 and φ60 layout are improved maximumly to 0.047°C and 0.068°C, respectively, all within the temperature range from ambient to 200°C. The non-equidistant heating resistor layout improved significantly the temperature uniformity of aluminum substrate, and laid a theoretical and application foundation for the realization of high temperature uniformity of the area blackbody source.