Transflective LCD Groove Structure for Bubble Prevention
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In transflective LCD devices, the thinning of substrates makes them prone to bending and liquid crystal material displacement under external loads, leading to bubble formation and degraded display quality due to difficulty in liquid crystal flow in reflection regions.
Innovation Solution
A groove is formed between pixels on the substrate facing the liquid crystal layer to facilitate easy flow of liquid crystal material, reducing the likelihood of bubble formation by maintaining the liquid crystal material's volume and preventing cracking in the insulating film.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Weight of stationary object
If substrates are thinned to reduce weight and thickness, then the device becomes lighter and thinner, but the substrates become prone to bending and liquid crystal material displacement under external loads
Solution Approach 1:
The substrate surface is segmented into pixel regions and groove regions. The grooves create distinct zones that allow controlled deformation and liquid crystal flow without compromising the overall structural integrity of the thinned substrate.
Solution Approach 2:
Different regions of the substrate are given different properties: pixel regions maintain standard thickness for display function, while groove regions are designed with specific depth and geometry to facilitate liquid crystal flow and absorb mechanical stress from external impacts.
2Illumination intensity
If transparent layers are formed in reflection regions to thin the liquid crystal layer, then optical path length is equalized, but liquid crystal material finds difficulty flowing in reflection regions
Solution Approach 1:
The groove structure adds a vertical dimension (depth) to the substrate surface, creating a three-dimensional pathway that enables liquid crystal flow in the reflection regions where the liquid crystal layer is thinned by transparent layers.
Solution Approach 2:
The grooves act as intermediary channels between pixel regions and reflection regions, providing a pathway for liquid crystal material to flow through areas where the liquid crystal layer thickness is reduced by transparent layers.
3Force
If a load is locally applied to the LCD device, then external impact is absorbed, but liquid crystal material flows outside the load-applied portion and bubbles form
Solution Approach 1:
Grooves are pre-formed in the substrate before the liquid crystal layer is filled. These grooves create predetermined pathways that guide liquid crystal flow during impact events, preventing uncontrolled flow and bubble formation.
Solution Approach 2:
The groove structure serves as a cushioning mechanism that anticipates and accommodates liquid crystal displacement during impact. The grooves provide space and pathways for the liquid crystal to move into during impact, then return to its proper position, preventing bubble formation.
4Illumination intensity
If the liquid crystal layer is thinned in reflection regions, then optical performance is improved, but the percentage of liquid crystal material decreases making bubble generation more likely
Solution Approach 1:
The groove structure compensates for the reduced liquid crystal volume in reflection regions by providing additional vertical space. The grooves create depth that allows sufficient liquid crystal material to be present even when the layer is thinned for optical performance.
Solution Approach 2:
The groove depth and geometry are carefully designed to adjust the local volume of liquid crystal material. By controlling the groove dimensions, the patent optimizes the balance between thinning the liquid crystal layer for optical performance and maintaining sufficient material volume to prevent bubbles.
Data Source
AI summary
A liquid crystal display device includes: a first substrate and a second substrate opposed to each other; and a liquid crystal layer placed between the first and second substrates. The device has a plurality of pixels each having a transmission region configured to transmit light coming from the first substrate side and a reflection region configured to reflect light coming from the second substrate side at the first substrate. A transparent layer is provided in the reflection region for rendering the liquid crystal layer thinner in the reflection region than in the transmission region. A groove is formed between the pixels on the surface of the first substrate facing the liquid crystal layer.