Yang Songlin, Wang Fengge, Ye Yong-Hong, Xia Yang, Deng Yun, Wang Jianguo, Cao Yurong
Opt Express. 2017 Oct 30;25(22):27551-27558. doi: 10.1364/OE.25.027551.
The imaging properties of BaTiO glass (BTG) microspheres in the diameter range of 5-50 µm which are fully immersed in a polydimethylsiloxane layer are experimentally studied. Our experimental results show that for both Blu-ray disc samples and the single-layer hexagonally close-packed microsphere array samples, with the increase of the diameter of BTG microspheres, the range of focal image positions (RFIP) increases linearly. When the diameter of BTG microspheres increases from 5 to 50 μm, the RFIP changes from 4 to 25 μm. For the microsphere array samples, Talbot effect is observed, and both the position of Talbot images and the Talbot distance depend on the diameter of BTG microspheres. Numerical simulations indicate that the length of the photonic nanojet changes from 2.9 to 7.1 μm when the BTG microsphere size increases from 5 to 50 μm, and the calculated RFIP is between 6 and 24 μm. The calculated RFIPs match well with the experimental ones. Our researches reveal that the RFIP depends on the length of the photonic nanojet of the BTG microsphere.
对完全浸没在聚二甲基硅氧烷层中的直径范围为5 - 50 µm的钛酸钡玻璃（BTG）微球的成像特性进行了实验研究。我们的实验结果表明，对于蓝光光盘样品和单层六方密堆积微球阵列样品，随着BTG微球直径的增加，聚焦图像位置范围（RFIP）呈线性增加。当BTG微球的直径从5 µm增加到50 µm时，RFIP从4 µm变化到25 µm。对于微球阵列样品，观察到了塔尔博特效应，塔尔博特图像的位置和塔尔博特距离都取决于BTG微球的直径。数值模拟表明，当BTG微球尺寸从5 µm增加到50 µm时，光子纳米射流的长度从2.9 µm变化到7.1 µm，计算得到的RFIP在6 µm到24 µm之间。计算得到的RFIP与实验结果吻合良好。我们的研究表明，RFIP取决于BTG微球的光子纳米射流的长度。
