Completely Hazy and Transparent Films by Embedding Air Gaps for Elimination of Angular Color Shift in Organic Light-Emitting Diodes.

Red, green, and blue top-emission organic light-emitting diodes (RGB TOLEDs) suffer from white color change with viewing angle due to the microcavity effect, called white angular dependence (WAD). Great efforts are devoted by applying various kinds of hazy films, but they suffer from poor mechanical stability and optical transmittance. Herein, we introduce an air-gap-embedded hazy film (AEHF) to solve these problems and suppress WAD in RGB TOLEDs.

Air-gap-embedded robust hazy films to reduce the screen-door effect in virtual reality displays.

We report a way to make an air-gap-embedded flexible film to reduce the screen-door effect (SDE) in virtual reality (VR) displays. Oxygen plasma was treated with a polyethylene terephthalate substrate to produce wavelength-scale micropatterns. These micropatterns induce an effective haze, but it is easily destroyed by a very small external scratch.

Optical Enhancement in Optoelectronic Devices Using Refractive Index Grading Layers.

We enhanced the optical transmittance of a multilayer barrier film by inserting a refractive index grading layer (RIGL). The result indicates that the Fresnel reflection, induced by the difference of refractive indices between Si(x)N(y) and SiO2, is reduced by the RIGL. To eliminate the Fresnel reflection while maintaining high transmittance, the optimized design of grading structures with the RIGL was conducted using an optical simulator.

Extracting optical modes of organic light-emitting diodes using quasi-periodic WO3 nanoislands.

Quasi-periodic WO(3) nanoislands are introduced to extract two optical modes in organic light-emitting diodes. The nano-scaled and size-tunable WO(3) islands were fabricated by use of wet-etching with self-aggregated Ag mask. The improvement of light extraction efficiency originates to the recovery of light losses which are surface plasmon mode and waveguide mode.

Improved light extraction efficiency in organic light emitting diodes with a perforated WO3 hole injection layer fabricated by use of colloidal lithography.

We present an organic light emitting diode with a perforated WO3 hole injection layer to improve the light extraction efficiency. The two-dimensionally perforated WO3 layer was fabricated by use of colloidal lithography. The light extraction efficiency was improved due to Bragg scattering of waveguide modes and surface plasmon polaritons, and the operating voltage was also decreased.