Zhang Xuehua, Xie Jingwei, Zhang Yaqi, Sun Rui, Liu Shun, Zhang Wei, Zhang Xinwen, Hu Fangren
Appl Opt. 2022 Feb 1;61(4):868-874. doi: 10.1364/AO.435517.
Poly (methyl methacrylate) (PMMA)-doped organic-inorganic composite films are prepared on flexible substrates through a combination of the sol-gel technique and the spin-coating method. Circular and hexagonal microlens arrays (MLAs) are then built into the composite films by using ultraviolet nanoimprint technology. Atomic force microscope and ultraviolet spectrophotometer characterization results of the films show that the films have low surface roughness and good optical transmittance. A scanning electron microscope is used to observe the surface morphology of the MLAs, and the results show that the prepared MLAs are regular and neat. The surface profiles of the MLAs are also measured by using a surface profiler. Optical microscopy results show that the prepared MLAs have good optical imaging properties. Finally, the MLAs are applied on the green organic light-emitting diodes (OLEDs), and the influence of the shape and diameter of the MLAs on the luminance and current efficiency of the OLEDs is discussed. Results indicate that there is a relatively high enhancement of the current efficiency and luminance for the OLEDs with hexagonal MLAs and a single microlens height of 9 µm, where the luminance can reach 10611/, and the current efficiency can be enhanced by about 20.1%. Furthermore, there is a higher enhancement of the luminance and current efficiency for the OLEDs with PMMA-doped MLAs than that of the OLEDs with no PMMA-doped MLAs. Based on these results, we believe that the obtained PMMA-doped composite film MLAs on flexible substrates have important applications in the flexible OLEDs displays areas.
通过溶胶-凝胶技术和旋涂法相结合，在柔性基板上制备了聚甲基丙烯酸甲酯（PMMA）掺杂的有机-无机复合薄膜。然后利用紫外纳米压印技术在复合薄膜中构建圆形和六边形微透镜阵列（MLA）。薄膜的原子力显微镜和紫外分光光度计表征结果表明，薄膜具有低表面粗糙度和良好的光学透过率。使用扫描电子显微镜观察MLA的表面形貌，结果表明所制备的MLA规则且整齐。还使用表面轮廓仪测量了MLA的表面轮廓。光学显微镜结果表明，所制备的MLA具有良好的光学成像特性。最后，将MLA应用于绿色有机发光二极管（OLED），并讨论了MLA的形状和直径对OLED的亮度和电流效率的影响。结果表明，对于具有六边形MLA且单个微透镜高度为9 µm的OLED，电流效率和亮度有较高的提高，其中亮度可达到10611/，电流效率可提高约20.1%。此外，与未掺杂PMMA的MLA的OLED相比，掺杂PMMA的MLA的OLED的亮度和电流效率有更高的提高。基于这些结果，我们认为在柔性基板上获得的掺杂PMMA的复合薄膜MLA在柔性OLED显示领域具有重要应用。
