Zhao Huijie, Ji Zheng, Li Na, Gu Jianrong, Li Yansong
School of Instrumentation Science & Opto-Electronics Engineering, Beihang University, 37 Xueyuan Road, Haidian District, Beijing 100191, China.
Sensors (Basel). 2016 Dec 29;17(1):56. doi: 10.3390/s17010056.
When detecting a target over the diurnal cycle, a conventional infrared thermal sensor might lose the target due to the thermal crossover, which could happen at any time throughout the day when the infrared image contrast between target and background in a scene is indistinguishable due to the temperature variation. In this paper, the benefits of using a multispectral-based infrared sensor over the diurnal cycle have been shown. Firstly, a brief theoretical analysis on how the thermal crossover influences a conventional thermal sensor, within the conditions where the thermal crossover would happen and why the mid-infrared (3~5 μm) multispectral technology is effective, is presented. Furthermore, the effectiveness of this technology is also described and we describe how the prototype design and multispectral technology is employed to help solve the thermal crossover detection problem. Thirdly, several targets are set up outside and imaged in the field experiment over a 24-h period. The experimental results show that the multispectral infrared imaging system can enhance the contrast of the detected images and effectively solve the failure of the conventional infrared sensor during the diurnal cycle, which is of great significance for infrared surveillance applications.
在昼夜周期内检测目标时，传统的红外热传感器可能会因热交叉而丢失目标，这种情况可能在一天中的任何时候发生，此时场景中目标与背景之间的红外图像对比度由于温度变化而难以区分。本文展示了在昼夜周期内使用基于多光谱的红外传感器的优势。首先，对热交叉在何种条件下会影响传统热传感器以及中红外（3~5μm）多光谱技术为何有效的情况进行了简要理论分析。此外，还描述了该技术的有效性以及如何采用原型设计和多光谱技术来帮助解决热交叉检测问题。第三，在野外实验中设置了多个目标并在24小时内进行成像。实验结果表明，多光谱红外成像系统可以增强检测图像的对比度，并有效解决传统红外传感器在昼夜周期中的失效问题，这对红外监视应用具有重要意义。
