Backlight Light Guide Edge Coupling Peripheral Brightness Gradient

The patent applies local quality by varying the backlight intensity across different regions of the display. The light guide is designed with position-dependent light extraction, where the central region maintains high light intensity for optimal display brightness, while the peripheral region has reduced light extraction to minimize the passepartout effect. This creates a gradient distribution where illumination intensity transitions from the center toward the edges, addressing both the need for bright display and reduced peripheral visibility.

The backlight system is segmented into different functional zones within the light guide structure. The light guide contains multiple light extraction regions with different optical characteristics - central extraction regions for primary illumination and peripheral extraction regions with reduced light output. This segmentation allows independent optimization of each zone's light extraction properties to achieve the desired illumination profile.

The patent employs a cost-effective approach by using a simple light guide structure with integrated microstructuring instead of complex local dimming matrix backlights. The light guide is manufactured as a single optical component with position-dependent light extraction properties achieved through microstructured surfaces or embedded particles. This eliminates the need for multiple independently controllable LED modules, reducing both device complexity and manufacturing cost while achieving the desired peripheral light reduction.

The patent replaces the mechanical/electrical control system of local dimming matrix backlights with an optical solution based on light guide microstructuring. Instead of using individually controllable LED elements and complex control electronics, the system uses passive optical elements (microstructures, particles, or layered designs) that inherently create the desired light distribution pattern through their physical structure, eliminating the need for active control mechanisms.