Mertz J, Gasecka A, Daradich A, Davison I, Coté D
Boston University, Department of Biomedical Engineering, 44 Cummington St., Boston, MA 02215 USA.
Centre de Recherche Université Laval Robert-Giffard (CRULRG), Université Laval, Québec, Qc, G1J 2G3, Canada ; Centre dOptique, Photonique et Laser (COPL), Université Laval, Québec, Qc, G1V 0A6, Canada.
Biomed Opt Express. 2014 Jan 8;5(2):407-16. doi: 10.1364/BOE.5.000407. eCollection 2014 Feb 1.
It is well known that the principle of reciprocity is valid for light traveling even through scattering or absorptive media. This principle has been used to establish an equivalence between conventional widefield microscopes and scanning microscopes. We make use of this principle to introduce a scanning version of oblique back-illumination microscopy, or sOBM. This technique provides sub-surface phase-gradient and amplitude images from unlabeled tissue, in an epi-detection geometry. That is, it may be applied to arbitrarily thick tissue. sOBM may be implemented as a simple, cost-effective add-on with any scanning microscope, requiring only the availability of an extra input channel in the microscope electronics. We demonstrate here its implementation in combination with two-photon excited fluorescence (TPEF) microscopy and with coherent anti-Stokes Raman scattering (CARS) microscopy, applied to brain or spinal cord tissue imaging. In both cases, sOBM provides information on tissue morphology complementary to TPEF or CARS contrast. This information is obtained simultaneously and is automatically co-registered. Finally, we show that sOBM can be operated at video rate.
众所周知，互易原理对于光在散射或吸收介质中的传播同样适用。这一原理已被用于建立传统宽视场显微镜和扫描显微镜之间的等效关系。我们利用这一原理引入了一种斜向背照式显微镜的扫描版本，即扫描斜向背照式显微镜（sOBM）。该技术在落射检测几何结构中，能从未标记组织获取亚表面相梯度和振幅图像。也就是说，它可应用于任意厚度的组织。sOBM可以作为一个简单、经济高效的附加组件与任何扫描显微镜结合使用，仅需显微镜电子设备中有一个额外的输入通道即可。我们在此展示了它与双光子激发荧光（TPEF）显微镜以及相干反斯托克斯拉曼散射（CARS）显微镜结合的实现方式，应用于脑或脊髓组织成像。在这两种情况下，sOBM都能提供与TPEF或CARS对比度互补的组织形态信息。这些信息是同时获取的，并且会自动配准。最后，我们表明sOBM可以以视频速率运行。
