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红外CCD在线温度场测量误差分析 总被引:3,自引:2,他引:1
红外CCD是通过采集高于绝对零度物体发出红外线并转化为图像来进行在线温度场测量的,得到的图像与物体的本身有一定的对应关系.由于受到很多干扰因素的影响,得到的温度场信息并不完全准确.造成的误差有很多,包括光学系统的误差、CCD器件本身带来的误差,还有就是红外辐射的干扰.对于前两者通过图像处理方法可以消除一部分误差,而红外辐射的干扰随机性比较大,利用一般的图像处理不能够完全解决.采用预埋热电偶的方法实时监测几个固定点的温度,然后利用这几个点的温度与CCD测的温度相比较,从而实时来校准系统的发射率.并利用修正后的系统发射率来计算被测物体的温度场分布,为了防止温度只是由于突然改变的系统的发射率发生突变.由此设计了温度场实时校准数学模型和修正系统,消除了部分温度场在线测量误差和突变,实现了红外CCD在线温度场的准确测量.实验结果表明,利用温度场实时修正系统来消除红外CCD温度场实时测量误差是可行的. 相似文献
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A self-powered sensitive ultraviolet photodetector based on epitaxial graphene on silicon carbide
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A self-powered graphene-based photodetector with high performance is particularly useful for device miniaturization and to save energy.Here,we report a graphene/silicon carbide(SiC)-based self-powered ultraviolet photodetector that exhibits a current responsivity of 7.4 m A/W with a response frequency of over a megahertz under 325-nm laser irradiation.The built-in photovoltage of the photodetector is about four orders of magnitude higher than previously reported results for similar devices.These favorable properties are ascribed to the ingenious device design using the combined advantages of graphene and SiC,two terminal electrodes,and asymmetric light irradiation on one of the electrodes.Importantly,the photon energy is larger than the band gap of SiC.This self-powered photodetector is compatible with modern semiconductor technology and shows potential for applications in ultraviolet imaging and graphene-based integrated circuits. 相似文献
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利用频率的定义推导了非相对论情形下及相对论情形下的多普勒效应公式,并用此推导过程解答了两个问题.主旨在于从本质上去理解多普勒效应的实质,更加深刻地理解多普勒效应的机制. 相似文献
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