图形化纳米结构色器件角敏机理及其色域拓展方法研究

Nano-structural color（NSC）will be the attractive replacements for colorant pigment employed by the display technologies. They will have great potential applications in flat-panel display，nano-printing, bionic, and optical security devices. However, the NSC are featured by its narrow viewing-angle. The observed colors change with the viewing-angle. Morever, the coverage rate of the color gamut is low leading to loss of color, and the graphical means is limited to the electron beam lithography. The above problems extremely limit the application of the NSC devices. In this work, we intend to improve the angle-independence of NSC devices through the nano-cavity resonance effect in the composite metal-dielectric nano-structure and complete angle-insensitive graphical sample production with high color gamut coverage. The maincontents of the project are as follows: i) Analysis of the near-field and far-field optical properties, including the oscillation of the free electrons in the metal film,the energy conversion between the photons and free electrons in the process of light transmission, the influence of the resonant mode (cavity modes, surface plasmon modes, etc.) on the angle-indendence, and the optimization of the structural parameters to achieve the spectral response with 80-100nm bandwidth almost unchanged until the viewing-angle increased to 45 degree; ii) Construct the mapping relationship between the color palettes with the spectral response and the structural parameters, set up and verify the color gamut expansion method; iii) Fabrication of the pixelated nanostructures based on the "Hybrid Lithography with UV pulsed laser" and directional evaporation process of metal film on the nanostructures with high duty cycle. The implementation of this project will provide new ideas, new solutions and new technologies for the NSC devices with angle-insensitive, wide color gamut,and arbitrary colored images.

纳米结构色有望替代颜料/染料，在新型平板显示、绿色纳米印刷、仿生和安全防伪等领域有重要应用，然而目前纳米结构色角度敏感、色域覆盖率低，在实现图形化颜色显示时，加工手段仅限于电子束光刻。本项目拟构建金属-介质纳米结构，利用纳米腔提升角敏性能，并以此实现低角敏、广色域、图形化的纳米结构色器件。主要研究内容包括：（1）近场和远场光学特性，重点研究金属中的自由电子震荡、光波传输过程中光子和自由电子的能量转换、存在的共振模式（谐振腔、表面等离子体波等）及其耦合对角敏性能的影响，优化获得±45度、宽带（80-100nm）滤光输出；（2）色品图与光谱响应、纳米腔的结构参数之间的映射关系，建立和验证颜色调色板形成方案；（3）基于“紫外脉冲激光混合光刻”技术的像素化纳米结构制作方法和高占宽比纳米结构定向蒸镀工艺研究。本项目的开展将为纳米结构色器件的设计、制备及应用提供新思路、新方案和新技术。

纳米结构色有望替代颜料/染料，在新型平板显示、绿色纳米印刷、仿生和安全防伪等领域有重要应用。低角敏、色域覆盖率低和高昂的成本是阻碍纳米结构色发展的主要瓶颈。本项目构建了金属-介质纳米结构，利用纳米腔提升角敏性能，并以此实现了低角敏、广色域、图形化的纳米结构色器件。主要研究内容包括：（1）近场和远场光学特性，重点研究金属中的自由电子震荡、光波传输过程中光子和自由电子的能量转换、存在的共振模式（谐振腔、表面等离子体波等）及其耦合对角敏性能的影响，优化获得±45度、宽带（80-100nm）滤光输出。（2）色品图与光谱响应、纳米腔的结构参数之间的映射关系，建立和验证了颜色调色板形成方案。颜色信息编码在二维金属纳米结构的尺寸参数中。调谐二维金属纳米结构的纳米腔共振决定了单个像素的颜色。我们的色彩映射策略产生的图像具有鲜明的色彩变化和精细的色调变化，适合大面积制备。（3）掌握了基于“紫外脉冲激光混合光刻”技术的像素化纳米结构制作方法。本项目实现了柔性、大面积和低成本的纳米结构色，在显示器、成像器件等表面弯曲或折叠，具有潜在应用前景。该项目的实施将为低角敏、宽色域、图形化的纳米结构色提供新的思路、新的解决方案和新技术。