Grating Sheet Reflects Non-Transmitted Light in LCD

The patent converts the harmful light absorption by black matrix regions into a beneficial effect by introducing a grating sheet that diffracts light. The grating sheet transforms the previously wasted light into useful diffracted light that can be utilized for display, thereby converting the harm of light absorption into the benefit of light redistribution and reuse.

The grating sheet acts as an intermediary component between the backlight module and the color filter substrate. It mediates the light path by diffracting light before it reaches the color filter substrate, enabling light that would otherwise be absorbed by black matrix regions to be redirected and utilized, thus improving overall light efficiency without fundamentally changing the conventional display structure.

The grating sheet is segmented into multiple sub-gratings (red sub-grating, green sub-grating, blue sub-grating) that correspond to different color regions. Each sub-grating is selectively formed in specific regions (e.g., red sub-grating in blue pixel region, green sub-grating in red pixel region, blue sub-grating in green pixel region), allowing light to be diffracted into appropriate color channels while maintaining manufacturing simplicity through region-specific patterning.

The grating sheet exhibits local quality by having different grating structures in different regions. Specifically, red sub-gratings are located in blue pixel regions, green sub-gratings in red pixel regions, and blue sub-gratings in green pixel regions. This localized grating configuration optimizes light diffraction for each color channel in its corresponding region while maintaining overall manufacturing simplicity.