Surface Light Source Device for LCD with RGB Center of Mass Alignment
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing surface light source devices for liquid crystal display units experience local color variations (color shifts) at the outer edge areas, leading to undesired color shifts in pixels, which affect image quality and contrast ratio.
Innovation Solution
A surface light source device with individually controlled light sources in each unit, where the center of mass of red, green, and blue light-emitting elements coincides with the center of the surface light source unit, and elements are arranged symmetrically and in specific orders along the sides to prevent color shifts, using LEDs and optical sensors for precise luminance control.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Illumination intensity
If four LEDs are arranged in one surface light source unit, then the light source can illuminate the display area, but local variation in luminescent color occurs in the outer edge area
Solution Approach 1:
The surface light source device is divided into multiple surface light source units (first, second, third, and fourth units), each responsible for illuminating specific display area units. This segmentation allows independent control and optimization of each unit's light-emitting elements, preventing color variation accumulation across the entire display area.
Solution Approach 2:
Each surface light source unit is configured with specific light-emitting element arrangements tailored to its position. The first and second units have light-emitting elements arranged along their long sides, while the third and fourth units have elements arranged along their short sides. This local customization ensures uniform color distribution in each unit's illumination zone.
Solution Approach 3:
Adjacent surface light source units are configured asymmetrically to prevent color variation at their boundaries. For example, the first unit has light-emitting elements arranged along its long sides, while the second unit has elements arranged along its short sides. This asymmetric configuration between adjacent units eliminates the color shift that would occur at their interface.
2Reliability
If surface light source units are controlled individually, then contrast ratio and image quality improve, but device complexity increases
Solution Approach 1:
The control system is segmented to match the physical segmentation of light source units. Each surface light source unit can be controlled independently, allowing the system to adjust luminance and color characteristics for different display areas without requiring a monolithic complex control architecture.
Solution Approach 2:
The control system applies local quality adjustments by configuring different light-emitting element arrangements in different units based on their positions. This allows targeted control of color and luminance in specific areas without affecting the entire display, simplifying the overall control strategy.
3Manufacturing precision
If light-emitting elements are arranged symmetrically in each unit, then color uniformity improves, but the arrangement flexibility decreases
Solution Approach 1:
Each surface light source unit employs symmetric arrangement of light-emitting elements relative to its own geometry, ensuring color uniformity within that unit. Simultaneously, the overall configuration adapts to different display area requirements by varying the number and arrangement of units, maintaining flexibility at the system level while ensuring precision at the unit level.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This configuration reliably prevents local color variations, enhances image quality by maintaining desired colors, and reduces power consumption while increasing contrast ratio through precise luminance control.
Implementation Method 1
a light source included in each of the surface light source units includes a plurality of light-emitting element units, and each of the light-emitting element units includes at least one red light-emitting element that emits red light, at least one green light-emitting element that emits green light, and at least one blue light-emitting element that emits blue light
Data Source
AI summary
A surface light source device which illuminates a transmission-type liquid crystal display unit from the back surface includes P×Q surface light source units with individually controlled light sources. Each of the light sources includes a plurality of light-emitting element units. Each of the light-emitting element units includes at least one red light-emitting element that emits red light, at least one green light-emitting element that emits green light, and at least one blue light-emitting element that emits blue light. The center of mass of a luminance profile based on each of a plurality of red light-emitting elements, a plurality of green light-emitting elements, and a plurality of blue light-emitting elements in each surface light source unit substantially coincides with the center of mass of the surface light source unit.