Illumination and scattered light detection using a light source consisting of sub-micrometer defect arrays formed on a extremely flat light waveguide core
Illumination and scattered light detection using a light source consisting of sub-micrometer defect arrays formed on a extremely flat light waveguide core
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使用由在极其平坦的光波导芯上形成的亚微米缺陷阵列组成的光源进行照明和散射光检测
DOI：
10.1007/s00542-014-2132-9
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发表时间：
2014
期刊：
影响因子：
--
通讯作者：
Yoshikazu Yoshida
中科院分区：
文献类型：
--
作者：
Toshifumi Ohkubo;Nobuyuki Terada;Yoshikazu Yoshida
我们以前认为，光学传感器结合全分析系统（TAS）是实现“无处不在的人类医疗保健”系统所需的不可或缺的功能组件之一。为了实现这一目标，我们提出了一种基本结构，用于使用平坦波导构造来照射沿沿着微流体通道运行的微小细胞或颗粒。这是可取的，TAS光源应尽可能接近试样流，以获得必要的光学性能，因此，人工缺陷上形成的平面光波导的表面上被认为是一个有前途的候选人，实现任意形状的光源的高功能的光学TAS结构。基于这一思想，我们制作了一种结构，即由亚微米尺寸的矩形固体组成的平面和方形光源，具有1 μm厚和12 μm宽的光波导芯。我们成功地试制了一种具有14 × 10 μm横截面的流体通道和极其平坦的光波导芯的光学TAS芯片。我们反复证实，当小心地引入650 nm波长的激光功率时，缺陷阵列可以作为近似方形的光源。在此基础上，提出了一种基于时域有限差分法和光束传播法的混合数值计算方法。利用这种混合方法，我们评估的光学响应时，一个粒子运行在整个光源，同时改变遮光罩的孔径长度，以获得具有更高的强度和更短的半峰全宽的信号。将数值结果与使用图像采集系统获得的实验结果进行了比较，并表现出良好的定性雅阁一致性。
We have previously argued that an optical sensor combined total analysis system (TAS) is one of the indispensable functional components needed to realize a “ubiquitous human healthcare” system. To achieve this goal, we have proposed a fundamental structure for illuminating a minute cell or particle running along a microfluidic channel using a flat waveguide construction. It is desirable that the TAS light source should be arranged as close to the specimen flow as possible in order to acquire the necessary optical properties; hence, artificial defects formed on the surface of a flat light waveguide are considered to be a promising candidate for realizing the arbitrary-shaped light source for a highly functional optical TAS structure. Based on this idea, we fabricated a structure, constructing a flat and square light source consisting of rectangular solids, sub-micrometer in size, with a 1-μm thick and a 12-μm wide light waveguide core. We successfully trial-manufactured an optical TAS chip with a fluidic channel containing a 14 × 10-μm cross section, and an extremely flat light waveguide core. We repeatedly confirmed that the defect array could function as an approximately square light source when a 650-nm wavelength laser power was carefully introduced. Furthermore, we developed a hybrid numerical calculation method base on the finite-difference, time-domain method together with the beam propagation method. Utilizing this hybrid method, we evaluated the optical response when a particle runs across the light source while changing the aperture length of a shading mask to obtain signals with both higher intensity and shorter full width at half maximum. The numerical results were compared with experimental results obtained using an image acquisition system, and demonstrated good qualitative accord.