Quantitative phase microscopy of thick objects

厚物体的定量相位显微镜

基本信息

批准号：
EP/N019563/1
负责人：
ANDREW MICHAEL MAIDEN
金额：
$ 12.62万
依托单位：
University of Sheffield
依托单位国家：
英国
项目类别：
Research Grant
财政年份：
2016
资助国家：
英国
起止时间：
2016 至无数据
项目状态：
已结题

来源：
https://gtr.ukri.org/projects?ref=EP%2FN019563%2F1
关键词：
Quantitative phase microscopy thick objects

项目摘要

Microscopes have always had trouble imaging thick specimens. The problem is that when the microscopist tries to focus on a plane deep within such objects, the image is swamped by out-of-focus background generated by the rest of the sample - and the higher the resolution required the worse this problem gets. The simplest solution is to physically slice the specimen very thinly, but this is time consuming and disruptive, destroying the sample's native state. The aim of this research is to investigate computational methods for achieving the same slicing effect, without the need to physically alter the specimen. We hypothesise that this can be achieved using a relatively new technique called ptychography, in combination with the sample rotation idea and algorithms from tomography. By unravelling the complex, multiple-scattering interaction of an illumination source with a thick specimen, we hope to stretch the 3D imaging capabilities of this hybrid approach beyond the limits imposed upon the conventional forms of these two techniques. Potential applications for the research stretch across the spectrum of microscope modalities. At infrared wavelengths detecting small defects in semiconductor wafers is an exciting application, currently beyond the reach of existing light-based inspection devices - the end result would be improved understanding of the lithographic process and better yields. For visible light, a primary example is the imaging of thick tissue specimens, a long-standing bugbear for biologists, who would benefit greatly from the ability to perform stain-free in vivo imaging at micron-scale resolutions. At the X-ray end of the spectrum, applications include the imaging of the lacuna-canalicular network of bone fragments and soft X-ray whole cell imaging, where both accuracy and achievable resolution will be greatly improved if the thickness limit inherent to the current imaging methods can be surpassed. For electrons, our research could improve the imaging of key material properties of semiconductors, such as doping concentrations and magnetic fields, measurement of which is vital to the development of future electronic devices.

显微镜在对厚样本成像时总是遇到困难。问题在于，当显微镜学家试图聚焦在此类物体深处的平面上时，图像会被样本其余部分产生的失焦背景所淹没 - 并且所需的分辨率越高，这个问题就越严重。最简单的解决方案是将样本物理切成非常薄的薄片，但这既耗时又具有破坏性，会破坏样本的自然状态。本研究的目的是研究实现相同切片效果的计算方法，而无需对样本进行物理改变。我们假设这可以通过使用一种称为叠层摄影的相对较新的技术，结合样本旋转思想和断层扫描算法来实现。通过揭示照明源与厚样本之间复杂的多重散射相互作用，我们希望将这种混合方法的 3D 成像能力扩展到这两种技术传统形式的限制之外。该研究的潜在应用涵盖了显微镜模式的各个领域。在红外波长下检测半导体晶圆中的小缺陷是一项令人兴奋的应用，目前超出了现有基于光的检测设备的范围 - 最终结果将是提高对光刻工艺的理解并提高产量。对于可见光，一个主要的例子是厚组织样本的成像，这是生物学家长期以来的一个难题，如果能够以微米级分辨率进行免染色体内成像，生物学家将受益匪浅。在 X 射线光谱端，应用包括骨碎片的腔隙-小管网络成像和软 X 射线全细胞成像，如果当前固有的厚度限制，则精度和可实现的分辨率都将大大提高成像方法是可以超越的。对于电子，我们的研究可以改善半导体关键材料特性的成像，例如掺杂浓度和磁场，这些测量对于未来电子设备的开发至关重要。