School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138, USA.
Sci Rep. 2013;3:2460. doi: 10.1038/srep02460.
Multispectral imaging is a powerful tool that extends the capabilities of the human eye. However, multispectral imaging systems generally are expensive and bulky, and multiple exposures are needed. Here, we report the demonstration of a compact multispectral imaging system that uses vertical silicon nanowires to realize a filter array. Multiple filter functions covering visible to near-infrared (NIR) wavelengths are simultaneously defined in a single lithography step using a single material (silicon). Nanowires are then etched and embedded into polydimethylsiloxane (PDMS), thereby realizing a device with eight filter functions. By attaching it to a monochrome silicon image sensor, we successfully realize an all-silicon multispectral imaging system. We demonstrate visible and NIR imaging. We show that the latter is highly sensitive to vegetation and furthermore enables imaging through objects opaque to the eye.
多光谱成像是一种强大的工具，可以扩展人眼的能力。然而，多光谱成像系统通常昂贵且庞大，并且需要多次曝光。在这里，我们报告了一种使用垂直硅纳米线实现滤光片阵列的紧凑型多光谱成像系统的演示。使用单一材料（硅），在单个光刻步骤中同时定义了覆盖可见到近红外（NIR）波长的多个滤光功能。然后对纳米线进行刻蚀并嵌入到聚二甲基硅氧烷（PDMS）中，从而实现具有八个滤光功能的器件。通过将其附着到单色硅图像传感器上，我们成功地实现了全硅多光谱成像系统。我们演示了可见和近红外成像。我们表明，后者对植被非常敏感，并且可以通过人眼无法看到的物体进行成像。
