高光譜影像(Hyperspectral imaging)在許多領域都有重要的應用，例如物質辨識、遙測(telemetry)等領域，而過去已開發的高光譜成像儀有些需要掃描並無法進行即時拍攝，或是因為高光譜成像儀需要使用到大量的光學元件導致重量過重，無法應用於太空遙測中。為了解決以上問題，本論文利用多波長共振與斜向超穎聚焦鏡的技術開發出具有即時快照(snapshot)與輕薄的平面式透鏡成像元件。
本論文利用多層膜反射鏡基板與銀金屬結構產生多波長共振，可以同時產生多個高品質因子的共振峰值，並且利用基板與銀棒間的介電質厚度可以控制共振波長的位置。結合幾何相位調製方式，可以在所有共振波段產生高效率圓偏振轉換效率並同時控制所有波長的相位，搭配斜聚焦鏡的相位設計原理，設計出在不同共振波長會有不同出射角度的斜向超穎聚焦鏡。由於離散的共振峰值與小NA的透鏡設計，在斜向聚焦平面上可以找到讓所有共振峰值都同時成像並且幾乎不重疊的影像平面。此研究成果展現出將超穎聚焦鏡於快照式高光譜影像發展與應用的可行性。

In this paper, an array of Ag nanoantennas standing on a distributed Bragg reflector (DBR) substrate are used to generate multi-wavelength resonance, which can bring multiple high-Q factor resonance peaks across the spectrum of interested. The spectral position of the resonance wavelengths can be adjusted by tuning the dielectric spacer thickness between the plasmonic nanoantennas and DBR substrate. Combined with the geometric phase method, the multi-resonant metasurface is capable of modulating the phase shift at individual wavelengths with high circular polarization conversion efficiency. With the design of geometric phase based multi-resonant metasurface, an off-axis meta-mirror is realized. Multiple focal spots can be obtained on a tilted focal plane when a broadband light source is illuminated, which is originally from the intrinsic dispersion effect of the metasurface. Due to the discrete resonant peaks and the small numerical aperture (NA) lens design, a color image is spectrally and spatially separated on the focal plane. We emphasize that the multi-imaging channels are realized by using noninterleaved metasurfaces, which can significantly improve the working efficiency and reduce the fabrication/design complexity. With the benefit of compact and easy to fabricate, the reported meta-imager paves a way for multispectral imaging and implementation of advanced optical systems.

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