Electrical Engineering Department, University of California, Los Angeles, Los Angeles, CA 90095, USA. Department of Bioengineering, University of California, Los Angeles, Los Angeles, CA 90095, USA. California NanoSystems Institute, University of California, Los Angeles, Los Angeles, CA 90095, USA.
Department of Bioengineering, University of California, Los Angeles, Los Angeles, CA 90095, USA.
Sci Transl Med. 2014 Dec 17;6(267):267ra175. doi: 10.1126/scitranslmed.3009850.
Optical examination of microscale features in pathology slides is one of the gold standards to diagnose disease. However, the use of conventional light microscopes is partially limited owing to their relatively high cost, bulkiness of lens-based optics, small field of view (FOV), and requirements for lateral scanning and three-dimensional (3D) focus adjustment. We illustrate the performance of a computational lens-free, holographic on-chip microscope that uses the transport-of-intensity equation, multi-height iterative phase retrieval, and rotational field transformations to perform wide-FOV imaging of pathology samples with comparable image quality to a traditional transmission lens-based microscope. The holographically reconstructed image can be digitally focused at any depth within the object FOV (after image capture) without the need for mechanical focus adjustment and is also digitally corrected for artifacts arising from uncontrolled tilting and height variations between the sample and sensor planes. Using this lens-free on-chip microscope, we successfully imaged invasive carcinoma cells within human breast sections, Papanicolaou smears revealing a high-grade squamous intraepithelial lesion, and sickle cell anemia blood smears over a FOV of 20.5 mm(2). The resulting wide-field lens-free images had sufficient image resolution and contrast for clinical evaluation, as demonstrated by a pathologist's blinded diagnosis of breast cancer tissue samples, achieving an overall accuracy of ~99%. By providing high-resolution images of large-area pathology samples with 3D digital focus adjustment, lens-free on-chip microscopy can be useful in resource-limited and point-of-care settings.
光学检查病理切片中的微观特征是诊断疾病的金标准之一。然而，由于传统的光学显微镜成本相对较高、透镜光学器件笨重、视场（FOV）较小以及需要横向扫描和三维（3D）焦点调整，其应用受到一定限制。我们展示了一种基于计算的无透镜、芯片上全息显微镜的性能，该显微镜使用强度传输方程、多高度迭代相位恢复和旋转场变换来对病理样本进行大视场成像，其图像质量可与传统的基于透镜的透射显微镜相媲美。在不进行机械焦点调整的情况下，全息重建的图像可以在物体 FOV 内的任何深度进行数字聚焦（在图像捕获后），并且还可以对由于样本和传感器平面之间不受控制的倾斜和高度变化引起的伪影进行数字校正。使用这种无透镜芯片上显微镜，我们成功地对人乳腺切片中的浸润性癌细胞、巴氏涂片显示的高级别鳞状上皮内病变以及镰状细胞贫血血涂片进行了成像，其 FOV 为 20.5mm(2)。由于病理学家对乳腺癌组织样本进行了盲法诊断，证明了这些宽场无透镜图像具有足够的图像分辨率和对比度，达到了约 99%的总体准确性。通过提供具有 3D 数字焦点调整的大面积病理样本的高分辨率图像，无透镜芯片上显微镜可在资源有限和即时护理环境中发挥作用。
