Light Guide Plate Circular Segment Elements Uniformity
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Liquid crystal displays (LCDs) face challenges in achieving uniform light distribution and high light output efficiency, particularly at different angles, due to the proximity of light guide plates to LEDs, which results in hot spots and non-uniform luminance.
Innovation Solution
A light guide plate design featuring first and second elongated elements with circular segment cross-sections on the entry and exit surfaces, respectively, arranged to optimize light distribution and efficiency, with specific pattern ratios and spacings to enhance light uniformity and reduce the number of required LEDs.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Length of moving object
If the light guide plate is placed closer to the LEDs to reduce bezel width, then the device achieves a slimmer design, but hot spots and non-uniform luminance occur at the edge of the light guide plate
Solution Approach 1:
The light guide plate is divided into multiple regions with different light guide structures: a first light guide structure with elongated elements having circular segment cross-sections on the light entry surface, and a second light guide structure with triangular prism elements on the light exit surface. This segmentation allows different regions to perform different functions - the circular segment elements scatter light to reduce hot spots near LEDs, while the triangular prism elements redirect light to achieve uniform distribution across the display area.
Solution Approach 2:
Different light guide structures are applied to different regions of the light guide plate based on local requirements. The first light guide structure with circular segment cross-sections is positioned at the light entry surface where hot spots occur, providing localized light scattering. The second light guide structure with triangular prisms is positioned at the light exit surface to provide localized light redirection and uniformity enhancement in that specific region.
2Illumination intensity
If conventional light guide structures are used to reduce hot spots, then light uniformity improves slightly, but light output efficiency at different angles remains insufficient
Solution Approach 1:
The first elongated elements on the light entry surface have circular segment cross-sections with curved surfaces. These curved surfaces refract and scatter light from the LEDs at multiple angles, effectively reducing hot spots while maintaining high light output efficiency. The curvature of the circular segments allows light to be distributed more uniformly across different viewing angles compared to flat or angular structures.
Solution Approach 2:
The invention transitions from conventional two-dimensional light guide patterns to three-dimensional light guide structures with specific cross-sectional geometries. The circular segment cross-sections and triangular prism shapes create vertical light scattering and redirection dimensions, enabling control of light distribution in multiple spatial dimensions simultaneously - both horizontally for uniformity and vertically for angular efficiency.
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
The design improves light uniformity and output efficiency at various angles, reducing hot spots and enabling the use of fewer LEDs, while being suitable for narrow bezel backlight modules.
Implementation Method 1
The light guide plate converts point light emitted by the LEDs into uniform planar light
Implementation Method 2
The light guide plate converts point light emitted by the LEDs into uniform planar light
Data Source
AI summary
A light guide plate includes a light entry surface with first elongated elements, and a light exit surface with second elongated elements. Each of the first and second elongated elements serves to guide light, and has a cross-section in a shape of a circular segment.