We report an angle-tilted, wavelength-multiplexed ptychographic modulation approach for multispectral lensless on-chip microscopy. In this approach, we illuminate the specimen with lights at five wavelengths simultaneously. A prism is added at the illumination path for spectral dispersion. Thus, lightwaves at different wavelengths hit the specimen at slightly different incident angles, breaking the ambiguities in mixed-state ptychographic reconstruction. At the detection path, we place a thin diffuser between the specimen and the monochromatic image sensor for encoding the spectral information into 2D intensity measurements. By scanning the sample to different $x\!-\!y$ positions, we acquire a sequence of monochromatic images for reconstructing the five complex object profiles at the five wavelengths. An up-sampling procedure is integrated into the recovery process to bypass the resolution limit imposed by the imager pixel size. We demonstrate a half-pitch resolution of 0.55 µm using an image sensor with 1.85 µm pixel size. We also demonstrate quantitative and high-quality multispectral reconstructions of stained tissue sections for digital pathology applications.

中文翻译：

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超分辨多光谱无透镜显微镜，通过倾斜角度，波长复用的谱图调制进行。

我们报告了多光谱无透镜片上显微镜的倾斜角度，波长复用谱图调制方法。在这种方法中，我们用五个波长的光同时照射样品。在照明路径上添加了一个棱镜，以实现光谱色散。因此，不同波长的光波以略微不同的入射角击中样本，打破了混合状态谱图重建中的歧义。在检测路径上，我们在样品和单色图像传感器之间放置了一个薄扩散板，用于将光谱信息编码为2D强度测量值。通过将样本扫描到其他$ x \！-\！y $位置，我们获取了一系列单色图像，用于在五个波长处重建五个复杂的对象轮廓。恢复过程中集成了上采样过程，以绕过成像器像素大小所施加的分辨率限制。我们使用像素尺寸为1.85 µm的图像传感器演示了0.55 µm的半间距分辨率。我们还演示了用于数字病理学应用的染色组织切片的定量和高质量多光谱重建。