PDLC Display Adhesive Layer for Uniform Luminance Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Display devices with polymer dispersed liquid crystal (PDLC) layers face issues with non-uniform luminance and decreased display quality due to the scattering and transmission of light, affecting the visibility of images.
Innovation Solution
A display device configuration with a transparent substrate, light source unit, and adhesive layer having a lower refractive index than the substrate, which controls the entry and distribution of light to maintain uniform luminance and suppress non-uniformity, using silicon oxide for the adhesive layer to form precise shapes that adjust light entry.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If a polymer dispersed liquid crystal layer is used to display images, then images can be displayed in scattering state, but luminance becomes non-uniform and display quality decreases
Solution Approach 1:
An adhesive layer with refractive index of 1.3 or lower is introduced as an intermediary between the display panel and the transparent substrate. This adhesive layer acts as a mediator to control light distribution and suppress non-uniform luminance while maintaining the image display capability of the PDLC layer.
Solution Approach 2:
The refractive index of the adhesive layer is specifically controlled to be 1.3 or lower to optimize light transmission and distribution. By changing this physical parameter, the patent achieves uniform luminance across the display panel while preserving the scattering state image display functionality.
2Ease of manufacture
If light is scattered by the PDLC layer to display images, then image visibility is achieved, but background visibility through the display panel is reduced
Solution Approach 1:
The PDLC layer dynamically switches between scattering and transparent states based on applied voltage. In the transparent state, the background becomes visible through the display panel, while in the scattering state, images are displayed. This dynamic switching resolves the contradiction between image display and background visibility.
Solution Approach 2:
The optical properties of the PDLC layer change dynamically - transitioning from a scattering state (opaque) to a transparent state (clear). This optical state change allows the display panel to alternate between displaying images and revealing the background, satisfying both requirements.
3Strength
If adhesive layer has high refractive index to ensure strong adhesion, then bonding strength is improved, but light transmission is reduced and luminance uniformity deteriorates
Solution Approach 1:
The refractive index of the adhesive layer is changed to be 1.3 or lower to optimize optical performance. This parameter change reduces light refraction and transmission loss at the interface, improving luminance uniformity while the adhesive properties are maintained through appropriate material selection.
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 ensures uniform luminance and maintains high display quality by optimizing light distribution, allowing clear image visibility and background recognition through the display of images in both transparent and scattering states, enhancing the user experience by maintaining the visibility of the background through the display device.
Implementation Method 1
an adhesive layer which adheres the display panel and the transparent substrate to each other and has a refractive index lower than that of the transparent substrate
Implementation Method 2
Polymer dispersed liquid crystal layers can switch between a scattering state, in which light is scattered, and a transparent state, in which light is transmitted
Data Source
AI summary
According to one embodiment, a display device includes a display panel for displaying images, a transparent substrate having a main surface opposing the display panel and a first side surface connected to the main surface, a light source unit for irradiating light toward the first side surface, and an adhesive layer that adheres the display panel and the transparent substrate and has a refractive index lower than that of the transparent substrate.