A coupled-mode theory for infrared and submillimeter wave detectors
A coupled-mode theory for infrared and submillimeter wave detectors
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红外和亚毫米波探测器的耦合模式理论
DOI：
10.1117/12.671942
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发表时间：
2006
影响因子：
5.7
通讯作者：
M. Hobson
中科院分区：
文献类型：
--
作者：
G. Saklatvala;S. Withington;M. Hobson
我们提出了一个新的理论描述的检测器的模式。虽然该理论是非常普遍的，它预计将特别用于远红外和亚毫米仪器的建模。这种理论是必要的，因为在远红外频率，光学系统和探测器都表现出部分相干行为。也就是说，即使当仪器被非相干光源照射时，检测器处的合成场也是部分相干的，并且检测器本身对场的相干特性敏感，而不仅仅是强度。我们以前开发了一个模式的描述光学系统在远红外波长，在这里，我们描述了一个模式理论的探测器本身。这些理论可以结合起来，提供一个完整的远红外仪器的模态描述。这里提出的理论同样适用于脉冲或遍历辐射，并纳入偏振效应。我们还展示了如何检测器输出的统计可以从理论上确定。这对于测辐射热计等仪器很重要，因为探测器的内部噪声非常低，主要是天空噪声或来自光学部件的辐射。我们说明了我们的工作与一些模拟，显示不同的检测器类型的信噪比，我们展示了如何将理论应用到阵列的堆积密度问题。
We present a new theory for the description of detectors in terms of modes. Although the theory is very general, it is expected to be of particular use in the modelling of far-infrared and submillimeter instruments. Such a theory is needed because at far-infrared frequencies, both optical systems and detectors show partially coherent behaviour. That is to say, even when the instrument is illuminated by an incoherent source, the resultant field at the detector is partially coherent, and the detector itself is sensitive to the coherence properties of the field and not just the intensity. We have previously developed a modal description of optical systems at far-infrared wavelengths; here we describe a modal theory for the detectors themselves. The theories can be combined to provide a complete modal description of far-infrared instruments. The theory presented here applies equally well to pulsed or ergodic radiation, and incorporates polarisation effects. We also show how the statistics of the detector output can be determined from the theory. This is important for instruments such as bolometers, where the internal noise of the detector is very low, and either sky noise or radiation from the optical components dominate. We illustrate our work with a number of simulations, showing signal to noise ratios for different detector types, and we show how how the theory may be applied to the array packing density problem.