摘要
凝视阵列型热像仪的空间噪声制约着热像仪对远距离目标的探测、分辨、跟踪性能。为解决热像仪空间噪声实际测量问题,分析了热像仪的空间噪声测量原理,给出了热像仪基于信号传递函数的空间噪声测量数学模型,介绍了热像仪某一组、某一区域或全部像素如何剔除时间域NETD,再通过统计计算得到其空间NETD的数学模型。对制冷型MCT320×256凝视列阵热像仪的SiTF和空间NETD进行测量,当背景黑体温度为5℃时,FOV区域中心信号传递函数(SiTF)为27.29 mV/℃,NETD为0.128℃,20℃时FOV区域中心SiTF为29.03℃,NETD为0.121℃。测量结果表明:该方法可评估空间噪声对热像仪性能的影响。
The spatial noise on staring array thermal imager restricts its capability in detecting , distinguishing and tracking the long distance targets .To solve the problem in measuring the thermal imager spatial noise ,its measuring theory was analyzed and the mathematical model for measuring the spatial noise based on signal transfer function (SiTF) was presented .After removing the temporal noise equivalent temperature difference (NETD) from the noise of a certain group or district or the whole pixels in thermal imager ,the spatial NETD model was calculated through analyzing statistically the noise of those pixels .In measuring the SiT F and spatial NETD of cooled MCT320 × 256 thermal imager ,when the temperature of the back‐ground blackbody is 5 ℃ ,the SiTF of central district in field of view(FOV) is 27 .29 mV/℃ , and the spatial NETD is 0 .128 ℃ .When the temperature of the background blackbody is 20 ℃ ,the SiTF of central district in FOV is 29 .03 mV/℃ ,and the spatial NETD is 0 .121 ℃ .The measuring results show that the measuring method can evaluate the influence of spatial noise on the perform‐ance of thermal imager .
出处
《应用光学》
CAS
CSCD
北大核心
2014年第6期1094-1098,共5页
Journal of Applied Optics
基金
国防科技工业技术基础科研项目
关键词
红外热像仪
空间噪声
固定模式噪声
时间噪声
NETD
infrared thermal imager
spatial noise
fixed pattern noise
temporal noise
noise equivalent temperature difference
