Light extraction enhancement from organic light-emitting diodes with randomly scattered surface fixture

Characterization of irregularly micro-structured surfaces related to their wetting properties

“…It has been known that the irregular surface roughness was effective in improving the light extraction in light-emitting diodes [13][14]. Moreover, it influenced the scattering light [15][16].…”

Optical Tunneling to Improve Light Extraction in Quantum Dot and Perovskite Light-Emitting Diodes

“…To extract this part of the lights from the substrate to air, thus contributing to the useful radiation, the external light extraction structure (EES) on the substrate is sufficient. Fortunately, a lot of research has been done on EES like prisms [43], micro-lens array [21], [22], roughened surface [44], [45] on substrates to extract a large fraction of lights from the substrate to air. These methods are not only low cost and convenient, but also avoid interruption of the internal device structure.…”

Lithographic convex pattern as a wavelength-independent light extraction structure for efficient organic light-emitting diodes

“…The challenges in realizing efficient OLEDs have triggered extensive efforts to develop efficient and practical concepts for light extraction. Typical strategies to extract the light trapped in the substrate mode include the application of microlens arrays, 14,15 volumetric scattering layers, 16,17 wrinkled films, 18,19 and a hemispherical lens 20,21 on the backside of the glass substrate. Although these external light extraction structures can boost device efficiency by a factor of 1.1–1.5, around 60% of internally generated photons remain trapped in thin-film waveguide modes and surface plasmons at the metal cathode.…”