Electrochromic Layer for Transflective LCD Contrast and Aperture
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Transflective liquid crystal display devices face challenges in achieving good display effects in both reflective and transmissive modes, with limited contrast and image resolution, and a complex fabrication process that increases production costs.
Innovation Solution
A transflective electrochromic liquid crystal display device is designed with an electrochromic layer between two electrode layers, allowing for electric field control of color, which replaces the color filter and enables both transmissive and reflective modes without decreasing resolution or aperture ratio, by using an electrochromic layer to reflect environmental light in the reflective mode and modulate backlight in the transmissive mode.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If a transflective liquid crystal display device uses a liquid crystal layer to modulate environmental light in reflective mode, then the device can display images in reflective mode, but the available contrast is limited and image resolution is insufficient
Solution Approach 1:
The patent employs an electrochromic layer that can change its optical properties (color, transparency, reflectivity) in response to applied voltage. This electrochromic material replaces the traditional liquid crystal layer for reflective mode operation, enabling high contrast and improved image resolution through precise control of light absorption and reflection characteristics at different voltage states.
Solution Approach 2:
The electrochromic layer serves multiple functions: it acts as both the reflective mode display element and the transmissive mode color filter. This multi-functional design eliminates the need for separate liquid crystal layers for different modes, thereby improving overall device performance and simplifying the structure while achieving good display effects in both reflective and transmissive modes.
2Adaptability or versatility
If a transflective liquid crystal display device divides sub-pixel area into transmissive and reflective areas, then both modes can be supported, but the aperture ratio is decreased and display properties are lowered
Solution Approach 1:
The electrochromic layer functions as a universal optical modulator that can operate in both reflective and transmissive modes across the entire sub-pixel area. By eliminating the need to divide the sub-pixel into separate transmissive and reflective regions, the aperture ratio is maintained while still achieving dual-mode operation with improved display properties.
Solution Approach 2:
The electrochromic layer dynamically changes its optical state based on applied voltage, allowing the same area to function differently for reflective and transmissive modes without physical division. This dynamic adaptability enables full utilization of the sub-pixel area while maintaining high aperture ratio and superior display characteristics in both modes.
3Ease of manufacture
If a transflective liquid crystal display device uses uniform liquid crystal cell thickness, then the fabrication process is simplified, but display effect in reflective mode is insufficient
Solution Approach 1:
The patent changes the fundamental parameter of the display mechanism from liquid crystal optical rotation to electrochromic color change. This parameter change allows the use of uniform cell thickness for simplified fabrication while achieving superior reflective mode display effect through the electrochromic layer's ability to precisely control light absorption and reflection at different voltage states.
4Illumination intensity
If a transflective liquid crystal display device uses a color filter substrate, then color display is achieved, but the fabrication process becomes complicated and production costs increase
Solution Approach 1:
The electrochromic layer replaces the traditional color filter substrate, serving as a universal optical element that provides both color display and mode selection functionality. This substitution simplifies the fabrication process by eliminating the need for complex color filter deposition and alignment steps, while reducing production costs through a more straightforward manufacturing approach.
Solution Approach 2:
The electrochromic layer achieves color display through voltage-controlled color changes of the electrochromic material itself, rather than relying on passive color filters. This active color control mechanism simplifies the overall device structure and fabrication process while maintaining excellent color display capability and enabling dual-mode operation.
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 achieves a good display effect in both modes with improved contrast and resolution, simplifying the fabrication process and reducing production costs by utilizing an electrochromic layer to enhance the sub-pixel region's functionality.
Implementation Method 1
the first and second electrode layers are adapted to apply an electric field to the electrochromic layer so as to change a color of the electrochromic layer
Implementation Method 2
utilizing an electrochromic layer to reflect environmental light in the reflective mode
Implementation Method 3
what is realized by a liquid crystal layer is to modulate environmental light which enters the liquid crystal cell
Data Source
AI summary
According to an embodiment of the present invention, there is disclosed a transflective electrochromic liquid crystal display device, comprising a first electrode layer, a second electrode layer and an electrochromic layer and a liquid crystal layer, wherein the electrochromic layer is located between the first electrode layer and the second electrode layer. The present invention can achieve a good display effect in each of a reflective mode and a transmissive mode; and production costs are low, and resolution and aperture ratio can be increased.