Microscale concave interfaces for structural reflective coloration

用于结构反射着色的微尺度凹面界面

• 批准号: 2111056
• 负责人: Chi Zhou
• 金额: $ 38.14万
• 依托单位: SUNY at Buffalo
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-09-01 至 2024-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2111056&HistoricalAwards=false
• 关键词: Microscale; concave; interfaces; structural; reflective

In everyday life, humans and machines rely on different colors to process important information. As modern physics advanced, our understanding of color generation expanded greatly, and different coloration phenomena were able to be characterized; some of which include optical dispersion (e.g. prism-induced rainbows), spectrally selective absorption (e.g. chemical pigments and resonant photonic structures), and thin-film interference (e.g. bubble and oil membranes). Structural colors in particular rely on optimizing their geometry to produce color, rather than utilize pigments or dyes. These structural coloration strategies have attracted considerable scientific and industrial interests because of their unique ability to manipulate the flow of light. In particular, a total internal reflection (TIR) interference introduced by microscale concave interfaces (MCI) was recently proposed, different from conventional coloration processes. It was believed that the incorporation of this new color creation mechanism into large scale displays and sensors is exciting but challenging to achieve. This NSF project will first perform a combined fundamental and experimental research to clarify the physical mechanism of this MCI. The major focus is to explore unambiguous physical mechanism of this new MCI structure, which will be validated through fabrication and systematic experimental characterization. Building upon these new optical interface structures, hybrid visible and infrared display technologies will be explored for light detection and ranging (LIDAR) applications. Realization of this new reflective coloration strategies is expected to yield important technological breakthroughs in information and display applications. The proposed micro-optics structure will foster the research and development with the broader impact on traffic safety, national security and sustaining the global leadership in photonics technologies. This research will be closely integrated with educational programs at University at Buffalo (UB). The research will inform development of new courses on Green Optoelectronic Devices and Senior Design Implementation. The research and current and future technology trends will be presented to a broader audience including K-12 teachers and students, and the general public.The investigator’s team developed a new MCI structure that can realize a unique reflective structural color, i.e., under different external optical illumination conditions, it can realize colorful retroreflection and iridescent reflection, respectively. It was believed that this type of structural coloration platform is different from conventional physical processes and can enable the exploration of new color display technologies and applications. Although it is generally agreed that this new reflective color is introduced by TIR inside the concave interface, a complete and accurate explanation to the coloration mechanism is still missing. This NSF project will first perform a combined fundamental and experimental research to clarify the physical mechanism of this MCI using thorough theoretical modeling and experimental validation. A combined ray-tracing and light coherent superposition modeling strategy will be developed to reveal the optical interference mechanism of the MCI structure. The color tunability by controlling the geometric and refractive index parameters will be investigated systematically using this combined modeling. Building upon the fundamental understanding of the new coloration mechanism, the investigator will develop traffic sign samples to explore smart signs for future remote sensing/imaging for autopilot systems. In particular, the time-of-flight of the laser from the LIDAR system will be characterized systematically to reveal the potential of the MCI in future autopilot applications. Due to the TIR-induced retroreflection feature, this type of new structure is especially suitable for low light environment (e.g. night-time traffic signs, advertisement boards, darkroom decoration for entertainment, etc.) and is promising to address the robust physical-world attacks on current deep learning visual classification used in LIDAR systems.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.

在日常生活中，人类和机器依靠不同的颜色来处理重要信息。随着现代物理学的发展，我们对颜色产生的理解大大扩展，并且能够表征不同的颜色现象。其中一些包括光学色散（例如棱镜引起的彩虹），光谱选择性吸收（例如化学色素和谐振光子结构）和薄膜干扰（例如，气泡和油膜）。尤其是结构上的颜色依靠优化其几何形状来产生颜色，而不是使用颜料或染料。这些结构性颜色策略吸引了被认为是科学和工业利益，因为它们具有独特的操纵光流。特别是，最近提出了由微观凹界面（MCI）引入的总内反射（TIR）干扰，与常规着色过程不同。人们认为，将这种新的颜色创造机制纳入大规模显示器和传感器是令人兴奋的，但要实现挑战。该NSF项目将首先执行一项组合的基本和实验研究，以阐明该MCI的物理机制。主要重点是探索这种新的MCI结构的明确的物理机制，该结构将通过制造和系统的实验表征来验证。将在这些新的光学接口结构的基础上，将探索混合可见和红外显示技术，以进行光检测和范围（LIDAR）应用。预计这种新的反思着色策略将在信息和显示应用程序中产生重要的技术突破。拟议的微观启发结构将促进研究和发展，对交通安全，国家安全和维持光子学技术的全球领导力产生更大的影响。研究将与布法罗大学（UB）大学的教育计划紧密融合。该研究将为开发有关绿色光电设备和高级设计实施的新课程。研究以及当前和未来的技术趋势将呈现给包括K-12教师和学生以及公众的更广泛的受众。人们认为，这种类型的结构颜色平台与常规的物理过程不同，并且可以探索新的彩色展示技术和应用程序。尽管通常认为这种新的反射颜色是在凹面界面内部引入的，但仍缺少对颜色机构的完整而准确的解释。该NSF项目将首先执行一项组合的基本和实验研究，以使用彻底的理论建模和实验验证来阐明该MCI的物理机制。将制定合并的射线追踪和光相干叠加建模策略，以揭示MCI结构的光学干扰机理。通过控制几何和折射率参数来控制颜色可密钉性，将使用此组合建模进行系统研究。在对新的着色机制的基本理解的基础上，研究人员将开发流量标志样本，以探索自动驾驶系统的未来遥感/成像的智能标志。特别是，从激光雷达系统的激光器的飞行时间将被系统地表征，以揭示MCI在未来的自动驾驶应用中的潜力。由于TIR引起的重新置换功能，这种新的结构特别适合弱光环境（例如，夜间交通标志，广告板，娱乐室的装饰等），并有望解决对当前对当前深度学习的强大的物理世界攻击的攻击。审查标准。

项目成果

Enhanced Schlieren System for In Situ Observation of Dynamic Light–Resin Interactions in Projection-Based Stereolithography Process

用于在基于投影的立体光刻工艺中对动态光与树脂相互作用进行原位观察的增强型纹影系统

• DOI: 10.1115/1.4062218
• 发表时间: 2023
• 期刊: Journal of Manufacturing Science and Engineering
• 作者: Chivate, Aditya;Zhou, Chi
• 通讯作者: Zhou, Chi

Multiple concentric rainbows induced by microscale concave interfaces for reflective displays

• DOI: 10.1016/j.apmt.2021.101146
• 发表时间: 2021-09
• 期刊: 2022 Conference on Lasers and Electro-Optics (CLEO)
• 作者: Jacob Rada;H. Hu;Lyu Zhou;Jing Zeng;Haomin Song;Xie Zeng;Shakil Shimul;Wen Fan;Q. Zhan

Microscale concave interfaces for reflective displays generate concentric rainbows

用于反射式显示器的微尺度凹面界面可产生同心彩虹

• DOI: 10.1364/fio.2022.jtu5b.49
• 发表时间: 2022
• 作者: Rada, Jacob;Hu, Haifeng;Zhou, Lyu;Zeng, Jing;Song, Haomin;Zeng, Xie;Shimul, Shakil;Fan, Wen;Zhan, Qiwen;Li, Wei
• 通讯作者: Li, Wei