Zdańkowski Piotr, Winnik Julianna, Patorski Krzysztof, Gocłowski Paweł, Ziemczonok Michał, Józwik Michał, Kujawińska Małgorzata, Trusiak Maciej
Warsaw University of Technology, Institute of Micromechanics and Photonics, 8 Św. A. Boboli st., 02-525 Warsaw, Poland.
These authors contributed equally to this work.
Biomed Opt Express. 2021 Jun 18;12(7):4219-4234. doi: 10.1364/BOE.428828. eCollection 2021 Jul 1.
In this work we propose an open-top like common-path intrinsically achromatic optical diffraction tomography system. It operates as a total-shear interferometer and employs Ronchi-type amplitude diffraction grating, positioned in between the camera and the tube lens without an additional 4f system, generating three-beam interferograms with achromatic second harmonic. Such configuration makes the proposed system low cost, compact and immune to vibrations. We present the results of the measurements of 3D-printed cell phantom using laser diode (coherent) and superluminescent diode (partially coherent) light sources. Broadband light sources can be naturally employed without the need for any cumbersome compensation because of the intrinsic achromaticity of the interferometric recording (holograms generated by -1 and +1 conjugated diffraction orders are not affected by the illumination wavelength). The results show that the decreased coherence offers much reduced coherent noise and higher fidelity tomographic reconstruction especially when applied nonnegativity constraint regularization procedure.
在这项工作中，我们提出了一种类似开顶式共光路的本征消色差光学衍射层析成像系统。它作为全剪切干涉仪运行，采用Ronchi型振幅衍射光栅，置于相机和管透镜之间，无需额外的4f系统，可产生具有消色差二次谐波的三光束干涉图。这种配置使所提出的系统成本低、结构紧凑且不受振动影响。我们展示了使用激光二极管（相干）和超发光二极管（部分相干）光源对3D打印细胞模型进行测量的结果。由于干涉记录的本征消色差特性（由 -1和 +1共轭衍射级产生的全息图不受照明波长影响），无需任何繁琐补偿即可自然地使用宽带光源。结果表明，降低的相干性可大大降低相干噪声，并提高层析重建的保真度，特别是在应用非负约束正则化程序时。
