BLC Pixel Optical Blocking Structure for Accurate Black Level Correction

The patent applies composite materials by combining multiple light blocking layers with different properties (metal layer, dielectric layer, and optionally infrared blocking layer) to achieve superior light blocking performance across different wavelengths. This composite structure effectively reduces light leakage compared to single-material blocks, thereby improving measurement accuracy while managing the increased structural complexity through systematic layer integration.

The light blocking structure is segmented into multiple functional layers: a metal layer for general light blocking, a dielectric layer for optical interference effects, and optionally an infrared blocking layer for specific wavelength ranges. This segmentation allows each layer to be optimized for its specific function, achieving comprehensive light blocking across the spectrum while maintaining manufacturability through standard semiconductor fabrication processes.

The composite light blocking structure serves multiple functions within a single integrated design: the metal layer provides general light blocking, the dielectric layer contributes to optical interference for enhanced blocking, and the infrared blocking layer addresses specific wavelength ranges. This multi-functionality allows a single structure to accomplish what would otherwise require multiple separate components, simplifying the overall manufacturing process despite the increased layer complexity.

The patent optimizes the optical properties of each layer by carefully controlling parameters such as layer thickness, refractive index, and material composition. By adjusting these parameters, the structure achieves maximum light blocking efficiency at different wavelengths through constructive and destructive interference effects, thereby improving measurement accuracy while keeping the manufacturing process within standard semiconductor fabrication capabilities.