Chang Robert C, Johnson Peter, Stafford Christopher M, Hwang Jeeseong
Biomed Opt Express. 2012 Jun 1;3(6):1326-39. doi: 10.1364/BOE.3.001326. Epub 2012 May 9.
We report on a novel fabrication approach to build multilayered optical tissue phantoms that serve as independently validated test targets for axial resolution and contrast in scattering measurements by depth-resolving optical coherent tomography (OCT) with general applicability to a variety of three-dimensional optical sectioning platforms. We implement a combinatorial bottom-up approach to prepare monolayers of light-scattering microspheres with interspersed layers of transparent polymer. A dense monolayer assembly of monodispersed microspheres is achieved via a combined methodology of polyelectrolyte multilayers (PEMs) for particle-substrate binding and convective particle flux for two-dimensional crystal array formation on a glass substrate. Modifications of key parameters in the layer-by-layer polyelectrolyte deposition approach are applied to optimize particle monolayer transfer from a glass substrate into an elastomer while preserving the relative axial positioning in the particle monolayer. Varying the dimensions of the scattering microspheres and the thickness of the intervening transparent polymer layers enables different spatial frequencies to be realized in the transverse dimension of the solid phantoms. Step-wise determination of the phantom dimensions is performed independently of the optical system under test to enable precise spatial calibration, independent validation, and quantitative dimensional measurements.
我们报告了一种新型的制造方法，用于构建多层光学组织模型，这些模型可作为轴向分辨率和散射测量中对比度的独立验证测试目标，通过深度分辨光学相干断层扫描（OCT）进行散射测量，普遍适用于各种三维光学切片平台。我们采用一种自下而上的组合方法来制备具有散布透明聚合物层的光散射微球单层。通过用于颗粒与底物结合的聚电解质多层膜（PEMs）和用于在玻璃底物上形成二维晶体阵列的对流颗粒通量的组合方法，实现了单分散微球的致密单层组装。在逐层聚电解质沉积方法中对关键参数进行修改，以优化颗粒单层从玻璃底物转移到弹性体中，同时保持颗粒单层中的相对轴向定位。改变散射微球的尺寸和中间透明聚合物层的厚度，可以在固体模型的横向维度上实现不同的空间频率。模型尺寸的逐步确定独立于被测光学系统进行，以实现精确的空间校准、独立验证和定量尺寸测量。
