P‐152: Emitter‐Apodization‐Dependent Angular Luminance Enhancement of Microlens‐Array Film Attached OLED Devices

Abstract

Taking organic emitter apodization calculated from electromagnetic theory as input, the angular luminance enhancement of a microlens-array-film (MAF) attached OLED (organic light-emitting device) can be further evaluated by raytracing approach. First, we assumed artificial emitters and revealed that not every OLED with MAF has luminance enhancement. Then, the OLEDs of different Alq 3 thickness were fabricated and their angular luminance measurement validated simulation results. Mode analyses for different layers were performed to estimate the enhancement potential of the MAF attached devices. In conclusion, the organic emitters with higher off-axis-angle luminous intensity cause lower out-coupling efficiency but gain higher enhancement after the MAF attached.

Device‐dependent angular luminance enhancement and optical responses of organic light‐emitting devices with a microlens‐array film

“…By increasing the normalized isotropic offset which implies broader apodization or higher off-axis viewing-angle intensity into the substrate, the relative luminous power and relative luminance in the normal direction (relative to that of each device without MAF) increases. 18 The relative luminance in the normal direction, relative luminous power, and the normalized isotropic offset of the four OLEDs of different Alq 3 thicknesses with MAF attachment are shown in Table 1. The normalized isotropic offset from large to small were for Alq 3 thicknesses of 140, 100, 20, and 60 nm; thereby the relative luminance in the normal direction and relative luminous power from large to small were for those of 140, 100, 20, and 60 nm, both numerically and experimentally.…”