Compact nano-void spectrometer based on a stable engineered scattering system
Compact nano-void spectrometer based on a stable engineered scattering system
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DOI：
10.1364/prj.465322
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发表时间：
2022-10-01
影响因子：
7.6
通讯作者：
Beresna, Martynas
中科院分区：
文献类型：
--
作者：
Sun, Qi;Falak, Przemyslaw;Beresna, Martynas
无序介质中光的随机散射可用于高灵敏度的基于散斑的波长计和光谱仪。然而，在紧凑空间内折叠长光路的多重散射事件也使得此类设备对振动和对无序介质的小干扰极其敏感。在这里，我们展示了如何设计散射，使其可用于对环境因素基本上不敏感的紧凑型计算光谱仪。我们设计并制造了散射效率为 62% 的三维伪随机纳米空隙图案。受控的多重散射量确保了 100 pm 目标分辨率的足够长的光程，并具有最佳的长期稳定性。 200 微米厚的散射二氧化硅基板与低成本相机传感器集成在一个紧凑的组件中。全光谱测量实现了目标分辨率，而单波长则可以以 50 pm 的分辨率确定。这种定制的散射系统可以改善计算光谱仪中成本、尺寸、稳定性和光谱分辨率之间的权衡。
Random scattering of light in disordered media can be used for highly sensitive speckle-based wavemeters and spectrometers. However, the multiple scattering events that fold long optical paths within a compact space also make such devices exceedingly sensitive to vibrations and small disturbances to the disordered media. Here, we show how scattering can be engineered so that it can be used for a compact computational spectrometer that is largely insensitive to environmental factors. We designed and fabricated a three-dimensional pseudo-random nano-void pattern with 62% scattering efficiency. The controlled amount of multiple scattering ensured a sufficiently long optical path for the target resolution of 100 pm, with optimal long-term stability. The 200-mu m-thick scattering silica substrate was integrated in a compact assembly with a low-cost camera sensor. The target resolution was achieved for full spectrum measurements while single wavelengths could be determined with 50 pm resolution. Such tailored scattering systems can improve the trade-off among cost, size, stability, and spectral resolution in computational spectrometers.