Simple, cost effective, and electronically-controlled condensers to increase the resolution and contrast of near-infrared microscopes

摘要非技术：当聚光镜被安装到光学显微镜中时，它会在被研究的样品上产生一个倾斜的锥形照明，从而提高成像分辨率。然而，现有的聚光器通常由多个透镜（或反射镜）和隔膜组成，应该进行机械调节。为了简化显微镜的使用和进一步提高成像分辨率，提出了一种新型光学聚光镜，它不需要移动部件，透镜或反射镜。这种新型光学聚光器是由一个中空的半球组成的，其内部表面含有大量的近红外发光二极管（led）。这种方法被称为电子控制聚光镜（ECC），允许多个倾斜照明角度，并将显微镜的分辨率提高一倍。所提出的ECC简单且具有成本效益，对于近红外成像显微镜特别重要。红外显微镜在检测，计量和可靠性分析方面具有广泛的应用，是半导体，光电和光子工业的宝贵诊断评估。在这项工作中提出的研究活动将为研究生和本科生在模拟，光学，高级显微镜，纳米和微制造领域提供优秀的跨学科培训。在这项努力下取得的成果将通过期刊出版物和会议发言加以传播。技术：ECC中每个近红外LED的独立电子控制将允许实现各种照明配置，包括但不限于明暗场显微镜，全方位，倾斜和圆形照明，红外层析成像和直接傅立叶光学滤波技术。此外，led在近红外中发射不同波长的可用性将使ECCs能够发射准单色或多色照明，其中波长选择由特定的近红外显微镜应用决定。提出的下一代远场近红外显微镜聚光镜的其他重要特性包括实时和无光栅图像，它免除了成像后处理重建的需要，并且使用简单且成本有效。这项工作包括模拟、制造、大阵列led的时空电子控制和变革性成像概念的研究，以实现简单的宽视场近红外亚波长分辨率。本提案下的研究涵盖了科学和工程领域广泛的技术和教育问题，并解决了重要的应用。本提案确定了四个主要研究重点：1。模拟：将进行模拟，以确定各种照明配置对应的最佳空间光强分布和分辨率极限。2. 空间和时间滤波：将对各种空间和时间照明方案下的图像分辨率和对比度进行全面研究，这些方案通过直接电子控制ECC中的单个或组led来实现。3. 制造：将制造控制纳米结构，以验证各种照明安排的分辨率限制。4. 成像程序：将研究半导体和光子工业中常用的各种样品的最佳成像照明程序。当这些研究结合起来时，将产生一种简单实用的近红外亚波长分辨率技术。具有多种空间和时间照明配置的ECCs代表了近红外显微镜领域的一种变革性技术。该研究将进一步加深对分辨率限制的理解，并将显著推动近红外显微成像技术的发展。

Title: Simple, cost effective, and electronically-controlled condensers to increase the resolution and contrast of near-infrared microscopesAbstractNon-technical: When a condenser is incorporated into an optical microscope, it produces a cone of inclined illumination incident on the sample under study resulting in improved imaging resolution. However, existing condensers typically comprises multiple lenses (or mirrors) and diaphragms that should be mechanically adjusted. In order to simplify the use of microscopes and further improve imaging resolution a novel optical condenser, which does not require moving parts, lenses, or mirrors, is proposed. The new optical condenser is formed by a hollow hemisphere containing a large number of near-infrared light emitting diodes (LEDs) in its internal surface. This approach, named as Electronic-Controlled Condenser (ECC), allows for multiple inclined illumination angles and doubles the resolution of the microscope. The proposed ECC is simple and cost-effective and will be particularly important for near-infrared imaging microscopy. Infrared microscopy has broad applications in inspection, metrology, and reliability analysis which are invaluable diagnostic assessments for the semiconductor, optoelectronic, and photonic industries. The research activities proposed in this effort will provide excellent interdisciplinary training for graduate and undergraduate students in the areas of simulation, optics, advanced microscopy, and nano- and micro-fabrication. Results obtained under this effort will be disseminated through journal publications and conference presentations. Technical: Independent electronic control of each near-infrared LED in an ECC will allow the implementation of a large variety of illumination configurations, which includes but are not limited to, bright and dark field microscopy, omni-directional, inclined, and circular illumination, infrared tomography, and direct Fourier optics filtering techniques. In addition, the availability of LEDs emitting at different wavelengths in the near-infrared will enable the realization of ECCs emitting quasi-monochromatic or polychromatic illumination where the wavelength selection is determined by specific near-infrared microscopy applications. Other important attributes of the proposed next generation condensers for far-field near-infrared microscopy include real-time and raster-free images, it dispenses the need of imaging post-processing reconstruction, and it is simple to use and cost effective. This effort encompasses research on simulations, fabrication, spatial and temporal electronic control of a large array of LEDs, and transformative imaging concepts to achieve simple wide-field near-infrared subwavelength resolution. Research under this proposal spans a broad range of technical and educational issues in science and engineering, and addresses important applications. Four major research thrusts were identified in this proposal: 1. Simulations: simulations will be performed to determine optimum spatial light intensity distribution and resolution limit corresponding to various illumination configurations. 2. Spatial and temporal filtering: a comprehensive study will be carried out on image resolution and contrast under a variety of spatial and temporal illumination schemes implemented by direct electronic control of individual or groups of LEDs in an ECC. 3. Fabrication: control nanostructures will be fabricated to verify the resolution limit for the various illumination arrangements. 4. Imaging procedures: the optimum imaging illumination procedures for a variety of samples commonly used in the semiconductor and photonic industries will be investigated. When integrated, these studies will result in a simple and practical subwavelength resolution technique in the near-infrared. ECCs with multiple spatial and temporal illumination configurations represents a transformative technology in the area of near-infrared microscopy. The proposed research will further the understanding on the resolution limits and will significantly advance the state of the art of near-infrared microscopy imaging.