Light Guide Plate Refractive Index for Transparent Display Luminance
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In transparent display devices, inappropriate selection of the refractive index of the light guide plate leads to reduced light source light reaching the liquid crystal layer, resulting in decreased luminance, and increasing the thickness of the light guide plate is not sufficiently effective in improving luminance gradient.
Innovation Solution
The refractive index of the light guide plate is set to be lower than that of the adhesive layer, preventing total reflection and ensuring that light source light propagates throughout the display panel, thereby improving luminance and addressing the luminance gradient issue.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Illumination intensity
If the refractive index of the light guide plate is increased to improve light propagation, then light source light can reach the liquid crystal layer more effectively, but total reflection occurs at the interface between the light guide plate and adhesive layer, causing luminance to decrease
Solution Approach 1:
The patent changes the refractive index parameter of the light guide plate to be lower than that of the adhesive layer. This parameter inversion prevents total reflection at the interface by ensuring that light travels from a lower refractive index medium to a higher refractive index medium, allowing light source light to effectively reach the liquid crystal layer without energy loss from total reflection.
Solution Approach 2:
The patent creates a composite structure where the light guide plate and adhesive layer are bonded together with specifically controlled refractive index relationships. By selecting materials with appropriate refractive index differences, the system optimizes light transmission while preventing total reflection, achieving both high luminance and efficient light propagation.
2Stability of the object's composition
If the thickness of the light guide plate is increased to suppress luminance gradient, then uniformity of luminance is improved, but the effectiveness of this measure is insufficient when the refractive index is not appropriately selected
Solution Approach 1:
The patent identifies that simply increasing thickness is insufficient without proper refractive index selection. By changing the refractive index parameter relationship (light guide plate lower than adhesive layer), the system achieves effective light propagation throughout the panel, making thickness adjustments more effective for suppressing luminance gradient and improving luminance uniformity.
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 enhances luminance by approximately 20% and effectively suppresses the luminance gradient phenomenon, improving the overall performance of the display device.
Implementation Method 1
refractive index of the first light guide plate is lower than refractive index of the first adhesive layer
Implementation Method 2
refractive index of the first light guide plate is lower than refractive index of the first adhesive layer
Data Source
AI summary
Used is a display device including: a first substrate having a first front surface and a first back surface located on an opposite side of the first front surface; a second substrate having a second back surface opposing the first front surface and a second front surface located on an opposite side of the second back surface; a liquid crystal layer arranged between the first front surface of the first substrate and the second back surface of the second substrate; a first light guide plate adhesively fixed onto the second front surface of the second substrate via a first adhesive layer; and a light source unit arranged at a position opposing a first side surface of the first light guide plate, in which refractive index of the first light guide plate is lower than refractive index of the first adhesive layer.