Superresolution lensfree microscopy

标题：超分辨率无透镜显微镜显微镜对研究生物系统、天然材料和人造设备很重要。使用可见光的光学显微镜传统上无法分辨小于一半波长的物体，这是一个通常比细菌小，但比病毒大的尺寸。对超分辨率显微镜的研究使更小的物体得以可视化，可用于在医学测试中识别病毒，了解细胞的内部生物机制如何运作，量化空气和水中的纳米级污染物，或对合成纳米材料进行表征，以确保它们按预期制造。一种特殊类型的光学显微镜，即无透镜显微镜，依靠计算算法从相机传感器上记录的阴影图案重建显微图像。它比传统显微镜更紧凑、更具成本效益，并提供更大的视野。这个项目的目标是用无透镜显微镜实现超分辨率，以可视化超小物体，同时保持无透镜显微镜的上述优势。除了研究生，本科生和高中生都参与了这个项目，一个新的教学模块正在创建中。无透镜显微镜的分辨率极限取决于各种因素，包括信噪比、相干性和衍射。相干无透镜显微镜以前达到了衍射限制的分辨率，而非相干无透镜显微镜(例如荧光成像)以前显示的分辨率比衍射极限差了好几倍。在这个项目中，超分辨率无透镜显微镜是通过在未知物体的消逝视场中放置一个纳米结构的掩膜来实现的。该掩模可以编码关于通常会由于绕射而丢失的对象的高分辨率信息(以稍后可解码的方式)。通过系统地扫描掩模的几何参数，研究团队正在产生关于分辨率提高可能达到的范围的知识。噪音的影响正在被量化。比较了不同重建算法的速度和分辨率。超分辨掩模几何估计的光学方法正在测试中。这些知识可以为理论模型提供信息，这些模型随后将用于指导未来改进的参数选择，这些改进可以通过紧凑和便携的设备以及快速的计算重建时间来实现更好的分辨率。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

Title: Superresolution Lensfree MicroscopyMicroscopy is important for studying biological systems, natural materials, and human-made devices. Optical microscopes that use visible light are traditionally incapable of resolving objects smaller than one-half the wavelength of the light, which is a size scale generally smaller than bacteria, but larger than viruses. Research into superresolution microscopy enables visualization of even smaller objects, which can be used to identify viruses in medical testing, learn how the inner biological mechanisms of cells operate, quantify nanoscale pollutants in air and water, or characterize synthesized nanomaterials to ensure that they are being manufactured as desired. A specific type of optical microscopy, lensfree microscopy, relies on computational algorithms to reconstruct microscopic images from shadow patterns recorded on a camera sensor. It is more compact and cost-effective than traditional microscopes and offers a larger field of view. The objective of this project is to achieve superresolution with lensfree microscopes to visualize ultra-small objects while maintaining the aforementioned advantages of lensfree microscopy. In addition to graduate students, undergraduates and high schoolers are involved in the project, and a new teaching module is being created.The resolution limit in lensfree microscopy depends on a variety of factors, including signal-to-noise ratio, coherence, and diffraction. Coherent lensfree microscopy has previously achieved diffraction-limited resolution, while incoherent lensfree microscopy (e.g., fluorescence imaging) has previously demonstrated resolution that is several times worse than the diffraction limit. In this project, superresolution lensfree microscopy is being achieved by positioning a nanostructured mask within the evanescent field of an unknown object. This mask can encode high resolution information (in a way that is later decodable) about the object that would normally be lost due to diffraction. By systematically sweeping geometric parameters of the mask, the research team is generating knowledge of what range of resolution boost is possible. The impact of noise is being quantified. The speed and resolution performance of different reconstruction algorithms are being compared. Optical methods of superresolved mask geometry estimation are being tested. This knowledge can inform theoretical models that will then be used to guide parameter choices for future improvements that can enable better resolution with compact and portable equipment and fast computational reconstruction times.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.