Barrier Film Optical Stack for Stable Quantum Dot Color Output

The patent applies parameter changes by precisely controlling the thickness of the organic coating layer (70-480 nm) and the optical path difference (within ±10 nm of integer multiples of 112.5 nm). This quantitative parameter optimization ensures that even when the organic coating layer swells in high humidity, the optical interference conditions remain stable, maintaining color consistency while preserving moisture and oxygen protection functionality.

The patent uses a composite barrier film structure combining inorganic oxide layers (providing barrier function) with organic coating layers (controlling optical properties). The inorganic oxide layers block moisture and oxygen, while the organic coating layers with specific thickness control light interference, creating a multi-functional composite that simultaneously achieves protection and color stability.

The patent optimizes the thickness parameter of the organic coating layer within the specific range of 70-480 nm and controls the optical path difference to be within ±10 nm of integer multiples of 112.5 nm. This precise parameter control allows the organic coating layer to provide adequate barrier performance while minimizing swelling-induced spectral shifts, as the optimized thickness creates stable optical interference conditions.

The patent applies partial action by using a moderate organic coating layer thickness (70-480 nm) that provides sufficient barrier performance without excessive thickness that would cause problematic swelling. This optimized thickness is enough to provide protection but not so thick as to cause severe color instability, achieving a balance between the two requirements.