Brightness Enhancement Stacked Layer for OLED Ambient Light Reflection

A brightness enhancement stacked layer comprising an absorptive polarizer layer, phase retardation layer, and reflective polarizer layer is introduced as an intermediary between the metal electrode and the external environment. This stacked layer mediates the interaction between ambient light and the metal electrode, allowing the electrode to maintain its electrical conductivity while preventing harmful light reflection. The absorptive polarizer layer absorbs polarized components of ambient light, the phase retardation layer modifies the polarization state, and the reflective polarizer layer reflects remaining polarized light away from the viewer, collectively eliminating the harmful reflection effect.

The brightness enhancement stacked layer employs a composite structure combining three different functional layers with distinct optical properties. The absorptive polarizer layer uses polarizing materials to absorb specific polarization states, the phase retardation layer uses birefringent materials to alter polarization phase, and the reflective polarizer layer uses polarizing reflective materials to redirect polarized light. This composite material approach allows simultaneous achievement of electrical conductivity (through the metal electrode) and reduction of ambient light reflection (through the composite optical stack).

The patent optimizes the optical parameters of each layer in the brightness enhancement stacked layer to minimize light loss. The absorptive polarizer layer is designed with specific absorption characteristics that selectively attenuate polarized components of ambient light while minimizing absorption of emitted display light. The phase retardation layer is engineered with precise retardation values to convert polarization states efficiently. The reflective polarizer layer is designed with high reflectivity for polarized light and high transmittivity for non-polarized emitted light. By carefully controlling these optical parameters, the system achieves contrast ratio improvement without significant light emission efficiency loss.

Each layer in the brightness enhancement stacked layer is designed with localized optical properties optimized for its specific function. The absorptive polarizer layer has localized absorption characteristics tailored to the polarization state of ambient light. The phase retardation layer has localized birefringence properties optimized for the wavelength range of display emission. The reflective polarizer layer has localized reflectivity characteristics that differentiate between emitted light and reflected ambient light. This local quality optimization ensures that each layer performs its specific function efficiently while minimizing overall light loss.