Light Guide Plate Adhesive Layer Bubble Structure for Bright Band Elimination
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional glass light guide plates in display modules suffer from low backlight utilization, low display brightness, and insufficient display effect due to the low refractive index of adhesives used, leading to a small total reflection angle and bright bands at the light-entering side, which results in inefficient light usage.
Innovation Solution
A light guide plate with a glass substrate, an adhesive layer containing a total reflection structure of bubbles, and a reflector, where the adhesive layer has a refractive index of 1.4 to 1.6 and a density of 0.9 g/cm3 to 1.1 g/cm3, and a barrier member surrounding the adhesive layer to prevent bubble escape and enhance light reflection.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Illumination intensity
If a conventional adhesive layer is used to bond the glass light guide plate to the reflector, then the structure is simple and easy to manufacture, but the refractive index is low (leading to small total reflection angle), causing low backlight utilization and bright bands at the light-entering side
Solution Approach 1:
The adhesive layer is designed with a porous structure containing bubbles distributed throughout. These bubbles create multiple interfaces with different refractive indices, increasing the total reflection angle and preventing light leakage. The porous structure transforms the homogeneous adhesive into a multi-phase composite that enhances optical performance while maintaining structural integrity.
Solution Approach 2:
The adhesive layer is formulated as a composite material combining adhesive matrix with dispersed bubble particles. This composite structure provides both the bonding function of the adhesive and the optical reflection enhancement from the bubbles, achieving high backlight utilization without requiring a completely different material system.
2Strength
If the adhesive layer thickness is increased to improve bonding strength, then the bonding becomes more reliable, but the total reflection angle decreases and bright bands appear at the light-entering side
Solution Approach 1:
The porous structure with bubbles is distributed throughout the adhesive layer regardless of thickness. This allows the adhesive layer to maintain both sufficient bonding strength and high total reflection angle even at greater thicknesses, as the bubbles provide continuous optical reflection interfaces throughout the entire thickness range.
Solution Approach 2:
The refractive index parameters of the adhesive layer are optimized by controlling bubble size, density, and distribution. By adjusting these parameters, the adhesive layer achieves both high bonding strength and high total reflection angle, resolving the trade-off between mechanical and optical performance.
3Stability of the object's composition
If a barrier member is added to completely surround the adhesive layer to prevent bubble escape, then bubble retention is improved, but the device complexity and manufacturing difficulty increase
Solution Approach 1:
Instead of completely surrounding the adhesive layer with a barrier member, the invention uses partial confinement where bubbles are generated and retained within the adhesive matrix itself through controlled stirring and curing processes. This partial action approach achieves bubble retention without the complexity of full barrier structures.
Solution Approach 2:
The adhesive layer itself serves the dual function of bonding and bubble containment through its porous structure. The bubbles are generated and trapped within the adhesive matrix during the curing process, eliminating the need for external barrier structures to prevent bubble escape.
4Illumination intensity
If the refractive index of the adhesive is increased to improve total reflection, then backlight utilization improves, but the adhesive material selection and cost increase
Solution Approach 1:
Rather than requiring a single adhesive material with high refractive index, the invention uses a composite of conventional adhesive with bubbles. This composite approach achieves high effective refractive index while maintaining compatibility with standard adhesive materials and existing bonding processes.
Solution Approach 2:
The effective refractive index of the adhesive layer is enhanced not by changing the base adhesive material but by modifying the physical parameters of the layer through bubble incorporation. This allows maintaining material compatibility while achieving the desired optical performance.
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 solution increases the ratio of light totally reflected by the light guide plate, prevents bright bands, and improves backlight utilization and display brightness, achieving high backlight utilization and excellent display effects.
Implementation Method 1
a total reflection structure distributed in the adhesive layer... the total reflection structure includes bubbles distributed in the adhesive layer... increases the ratio of light totally reflected by the light guide plate
Implementation Method 2
a barrier member arranged between the glass substrate and the reflector and surrounding the adhesive layer
Data Source
AI summary
A light guide plate, a manufacturing method thereof, and a display device are provided. The light guide plate includes a glass substrate, an adhesive layer arranged at a surface of the glass substrate, a reflector arranged at a surface of the adhesive layer away from the glass substrate, and a total reflection structure distributed in the adhesive layer.