Display Pixel Multi-LSB Dithering for Low-Gray Uniformity

The patent segments the gray level range into two distinct regions: low gray levels (below threshold GL_th) and high gray levels (above threshold GL_th). For low gray levels, it uses multi-LSB dithering that maps to a broader range (GL_0 to GL_th) rather than adjacent levels, while high gray levels use traditional dithering. This segmentation allows different dithering strategies to address the specific characteristics of each region, resolving the contradiction between luminance precision and pixel uniformity.

The patent applies different dithering qualities to different regions of the gray level spectrum. Low gray levels receive multi-LSB dithering with a threshold-based mapping strategy that accounts for pixel non-ideality, while high gray levels receive standard dithering. This local differentiation ensures that each region receives the appropriate treatment for its specific characteristics, improving both luminance precision and pixel uniformity where needed.

The patent extracts the problematic low gray level range (below GL_th) from the overall dithering process and applies a specialized multi-LSB dithering strategy only to this extracted region. By isolating the low gray level handling, the complexity is contained to a specific function rather than affecting the entire dithering system, making the increased complexity manageable and targeted.

The patent changes the dithering parameters specifically for low gray levels by introducing a threshold gray level GL_th and using a multi-LSB mapping function that differs from the standard dithering parameters. This parameter change allows the system to achieve better pixel uniformity while keeping the complexity localized to parameter adjustments rather than fundamental architectural changes.

The patent applies preliminary anti-action by preemptively avoiding the use of gray levels near the threshold voltage region for low gray level representation. Instead of using GL_N and GL_N+1 adjacent to threshold, it maps low gray levels to GL_0 and GL_th, staying clear of the problematic threshold activation zone. This preliminary avoidance prevents luminance output accuracy deterioration before it can occur.

The patent introduces an intermediary mapping function that translates desired low gray level values into output levels that skip the problematic threshold region. This intermediary function acts as a mediator between the input gray level signal and the pixel activation, ensuring that the problematic threshold voltage region is not directly engaged while still achieving accurate low gray level representation.