Abstract

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 ${{10611}}\;{\rm{cd/c}}{{\rm{m}}^2}$, 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.

© 2022 Optical Society of America

Fabrication of microlens arrays with high filling factors by combining a thermal reflow and parylene CVD technique and the applications on OLEDs

Rui Sun, Xuehua Zhang, Yaqi Zhang, Xinwen Zhang, and Fangren Hu
Appl. Opt. 61(11) 3048-3053 (2022)

Patterned microlens array for efficiency improvement of small-pixelated organic light-emitting devices

Hoang-Yan Lin, Yu-Hsuan Ho, Juin-Haw Lee, Kuan-Yu Chen, Jheng-Hao Fang, Sheng-Chih Hsu, Mao-Kuo Wei, Hung-Yi Lin, Jen-Hui Tsai, and Tung-Chuan Wu
Opt. Express 16(15) 11044-11051 (2008)

Random Al₂O₃ nanoparticle-based polymer composite films as outcoupling layers for flexible organic light-emitting diodes

Chur-Hyun Shin, Gunel Huseynova, Eunhye Kim, Jonghee Lee, Seunghyup Yoo, Yoonseuk Choi, and Jae-Hyun Lee
Opt. Express 28(18) 26170-26179 (2020)

Enhanced light out-coupling of organic light-emitting diode using metallic nanomesh electrodes and microlens array

Yu-Hsuan Ho, Kuan-Yu Chen, Kai-Yu Peng, Ming-Chih Tsai, Wei-Cheng Tian, and Pei-Kuen Wei
Opt. Express 21(7) 8535-8543 (2013)

Titanium content influence on the optical response characteristics of TiO₂/ormosils composite films doped with azobenzene

Xuehua Zhang, Shun Liu, Chu Xue, Wei Zhang, Rui Sun, and Fangren Hu
Appl. Opt. 60(19) 5581-5587 (2021)