Schonbrun Ethan, Steinvurzel Paul E, Crozier Kenneth B
School of Engineering and Applied Science, Harvard University, Cambridge, MA 02138, USA.
Opt Express. 2011 Jan 17;19(2):1385-94. doi: 10.1364/OE.19.001385.
We demonstrate an opto-fluidic detection system based on an array of astigmatic diffractive microlenses integrated into a microfluidic flow focus device. Each astigmatic microlens produces a line excitation across the channel and collects fluorescence emission from the linear detection regions. The linear excitation spot results in uniform excitation across the channel and high time resolution in the direction of the flow. Collected fluorescence from each integrated microlens is relayed to a sub-region on a fast CMOS camera. By analyzing the signal from individual microlenses, we demonstrate counting and resolution of 500 nm and 1.1 μm beads at rates of up to 8,300 per second at multiple locations. In addition, a cross-correlation analysis of the signals from different microlenses yields the velocity dispersion of beads traveling through the channel at peak speeds as high as 560 mm/s. Arrays of specifically designed diffractive optics promise to increase the resolution and functionality of opto-fluidic analysis such as flow cytometry and fluorescence cross-correlation spectroscopy.
我们展示了一种基于散光衍射微透镜阵列的光流检测系统，该阵列集成在微流体流动聚焦装置中。每个散光微透镜在通道上产生一条线激发，并收集来自线性检测区域的荧光发射。线性激发光斑可在整个通道上实现均匀激发，并在流动方向上具有高时间分辨率。从每个集成微透镜收集的荧光被中继到快速CMOS相机上的一个子区域。通过分析来自单个微透镜的信号，我们展示了在多个位置以高达每秒8300个的速率对500 nm和1.1 μm珠子进行计数和分辨。此外，对来自不同微透镜的信号进行互相关分析，可得出珠子以高达560 mm/s的峰值速度通过通道时的速度色散。专门设计的衍射光学阵列有望提高光流分析（如流式细胞术和荧光互相关光谱）的分辨率和功能。
