Spontaneously Buckled Microlens for Improving Outcoupled Organic Electroluminescence

We fabricate a buckling structure by thermally depositing aluminum on a polymer surface and cooling it to room temperature, and utilize the structure as a microlens aggregate for organic light emitting diodes. The aspect ratio of the lens is increased by a multiple deposition process. We demonstrate that the characteristics of the outcoupled emission of this device are improved from various perspectives such as efficiency, emission angle, and reduced spectral change. These improved characteristics originate from randomized double-curvatured lens structure with full surface coverage.