Andersson David, Bao Yupan, Kornienko Vassily, Popović Dean, Kristensson Elias
Division of Combustion Physics, Department of Physics, Lund University, Professorsgatan 1, 22363, Lund, Sweden.
Institute of Physics, Bijenička cesta 46, 10000, Zagreb, Croatia.
Sci Rep. 2024 Jul 12;14(1):16116. doi: 10.1038/s41598-024-66386-2.
The study of rapid and stochastic events that involve multiple species, such as chemical reactions and plasma dynamics, requires means to capture multispectral information in two dimensions at both high temporal- and spatial resolution. Commercially available cameras that provide high temporal resolution are based on either signal intensification or rapid data acquisition. Intensified cameras provide extremely short acquisition times using intensification by means of micro channel plates, but the conversion between electrons and photons makes these cameras inherently monochrome. In contrast, high-speed cameras can achieve color-sensitivity through integrated Bayer filters but suffer from a reduced light collection efficiency and a fixed spectral composition. In this article we present a non-integrated optical arrangement for instantaneous multispectral imaging based on FRAME image multiplexing. By spectrally separating the signal using lossless dichroic mirrors, a 16-fold increase in light-collection efficiency is gained (compared to past solutions), resulting in an equivalent increase in temporal resolution. This improvement provides new avenues for multispectral imaging of rapid events. We demonstrate the system's versatility and suitability for studies of such processes by applying it for (i) temperature mapping using a high-resolution CCD camera, (ii) high-speed videography up to 10 kHz at four spectral channels and (iii) dual-species visualization in a plasma discharge using an intensified sCMOS camera.
对涉及多种物质的快速随机事件（如化学反应和等离子体动力学）的研究，需要在高时间和空间分辨率下在二维空间中获取多光谱信息的手段。市售的提供高时间分辨率的相机基于信号增强或快速数据采集。增强型相机通过微通道板进行增强，可提供极短的采集时间，但电子与光子之间的转换使这些相机本质上是单色的。相比之下，高速相机可通过集成的拜耳滤镜实现颜色敏感度，但存在光收集效率降低和光谱组成固定的问题。在本文中，我们展示了一种基于帧图像复用的用于瞬时多光谱成像的非集成光学装置。通过使用无损二向色镜对信号进行光谱分离，光收集效率提高了16倍（与过去的解决方案相比），从而使时间分辨率得到同等提高。这一改进为快速事件的多光谱成像提供了新途径。我们通过将该系统应用于：（i）使用高分辨率CCD相机进行温度映射；（ii）在四个光谱通道上以高达10kHz的速度进行高速摄像；以及（iii）使用增强型sCMOS相机在等离子体放电中进行双物种可视化，证明了该系统在此类过程研究中的通用性和适用性。
