Improved out-coupling efficiency from a green microcavity OLED with a narrow band emission source

A highly efficient green microcavity organic light emitting diode was developed using a tetradentate cyclometalated platinum complex, PtN1N, with an intrinsically narrow emission spectral band (FWHM = 18 nm). Devices employing the narrow band emitter in MOLEDs consisting of a single pair of a high index dielectric, Ta2O5, and low index dielectric, SiO2, exhibited a high peak external quantum efficiency of 33.7% compared to a standard OLED in the same device architecture with a peak external quantum efficiency of 25.6%. We have also found in our study that narrow band emission sources in tuned microcavity OLEDs exhibit larger enhancements in light out-coupling efficiency accompanied by small changes in color with respect to viewing angle compared to broad band emitters which is advantageous in display applications. (C) 2016 Elsevier B.V. All rights reserved.