Hefei National Laboratory for Physical Sciences at the Microscale, Advanced Laser Technology Laboratory of Anhui Province, Department of Optics and Optical Engineering, University of Science and Technology of China, 230026, Hefei, Anhui, China.
College of Science, Guilin University of Technology, 541004, Guilin, Guangxi, China.
Nat Commun. 2021 Nov 25;12(1):6835. doi: 10.1038/s41467-021-27231-6.
A limitation of standard brightfield microscopy is its low contrast images, especially for thin specimens of weak absorption, and biological species with refractive indices very close in value to that of their surroundings. We demonstrate, using a planar photonic chip with tailored angular transmission as the sample substrate, a standard brightfield microscopy can provide both darkfield and total internal reflection (TIR) microscopy images with one experimental configuration. The image contrast is enhanced without altering the specimens and the microscope configurations. This planar chip consists of several multilayer sections with designed photonic band gaps and a central region with dielectric nanoparticles, which does not require top-down nanofabrication and can be fabricated in a larger scale. The photonic chip eliminates the need for a bulky condenser or special objective to realize darkfield or TIR illumination. Thus, it can work as a miniaturized high-contrast-imaging device for the developments of versatile and compact microscopes.
标准明场显微镜的一个局限性是其对比度低的图像，特别是对于弱吸收的薄标本，以及折射率非常接近周围环境的生物物种。我们使用具有定制角度传输的平面光子芯片作为样品基底来证明，标准明场显微镜可以在一种实验配置下提供暗场和全内反射（TIR）显微镜图像。在不改变标本和显微镜配置的情况下，增强了图像对比度。这种平面芯片由几个具有设计光子带隙的多层部分和一个带有介电纳米粒子的中心区域组成，它不需要自上而下的纳米制造，并且可以在更大的规模上制造。光子芯片消除了对笨重聚光器或特殊物镜的需求，以实现暗场或 TIR 照明。因此，它可以作为一种小型化的高对比度成像设备，用于开发多功能和紧凑的显微镜。
