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Vitreous collagen structure plays an important role in ocular mechanics, but capturing this structure with existing vitreous imaging methods is hindered by loss of sample position and orientation, low resolution, or small field of view. The objective of this study was to evaluate confocal reflectance microscopy as a solution to these limitations. The use of intrinsic reflectance avoids staining and optical sectioning eliminates the requirement for thin sectioning, minimizing processing for optimal preservation of natural structure. We developed a sample preparation and imaging strategy usingex vivogrossly sectioned porcine eyes. Imaging revealed a network of uniform diameter crossing fibers (1.1 ± 0.3 μm for a typical image) with generally poor alignment (alignment coefficient = 0.40 ± 0.21 for a typical image). To test the utility of our approach for detecting differences in fiber spatial distribution, we imaged eyes every 1 mm along an anterior-posterior axis originating at the limbus and quantified the number of fibers in each image. Fiber density was higher anteriorly near the vitreous base, regardless of imaging plane. These data demonstrate that confocal reflectance microscopy addresses the previously unmet need for a robust, micron-scale technique to map features of collagen networksin situacross the vitreous.

A hyper-lens with planar object/image surfaces and uniform magnification factor is designed based on directional projecting property of optic-null medium (ONM). The proposed planar hyper-lens only requires one homogeneous anisotropic medium, i.e. ONM. We use metallic plates inside ϵ-near-zero medium to realize the proposed hyper-lens. 0.191λ 0 resolution is observed (0.238λ 0 can be clearly resolved) in experimental measurement, which consists very well with 3D numerical simulations and verifies the performance of the proposed planar hyper-lens. The planar hyper-lens with uniform pre-designed magnification factor may have some applications in super-resolution imaging technology.