Abstract
Microlens arrays film fabricated by UV roll-to-roll nanoimprinting lithography is introduced on glass substrate to improve the out-coupling efficiency of organic light-emitting devices. The microlenses suppress wave guiding loss in the substrate and a theoretical model, based on Monto-Carlo model, is developed to simulate the enhancement effects. The numerical results show that ellipsoidal-like microlens array can increase the efficiency by a factor of more than 35% and the luminance density distribution along the orthogonal directions can be compressed by 10 degree. Such a microlens array mold is fabricated by a combination of DMD-based laser direct writing lithography and thermal reflow method, followed by electroforming for transferring the surface structure to a nickel plate. The obtained mold is wrapped on a roller for the mass production of microlens array film by UV roll-to-roll nanoimprinting process. OLED attached with such microlens array film with a maximum increase of 35% in efficiency is achieved and directional out-coupling phenomenon can be observed experimentally. Such a directional out-coupling microlens array film can be used to OLED to enhance the luminous intensity efficiency and save power consumption for future lighting and display application.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have