Cholesteric Liquid Crystal Display Panel Without Polarizers
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current liquid crystal display (LCD) devices require two polarizers with perpendicular polarization directions, leading to low transmittance and a narrow color gamut, making it difficult to achieve a wide color gamut like Adobe RGB or DCI P3.
Innovation Solution
A display panel design featuring a liquid crystal layer with a first and second cholesteric liquid crystal layer stacked oppositely, where the spiral direction of one layer is opposite to the other, eliminating the need for polarizers by using a blue backlight source and color film layers to modulate light, allowing for improved transmittance and color gamut.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Illumination intensity
If two polarizers with perpendicular polarization directions are used to modulate light in LCD devices, then the liquid crystal layer can effectively modulate light, but the transmittance of the display device is significantly lowered
Solution Approach 1:
The patent removes the polarizer component from the LCD structure entirely. Instead of using polarizers to modulate light, the invention uses a blue backlight source combined with color film layers (red, green, blue) to achieve color display. This extraction of the polarizer eliminates the transmittance loss associated with polarizing filters while maintaining the light modulation function through the liquid crystal's interaction with the blue light and color films.
Solution Approach 2:
The patent changes the spectral parameters of the backlight from a traditional white backlight to a blue backlight with specific wavelength characteristics. This parameter change allows the liquid crystal layer to interact with monochromatic blue light, which then passes through color film layers to produce the full color spectrum. This approach improves transmittance by eliminating the need for polarizers while achieving wide color gamut through the blue backlight and color conversion films.
2Illumination intensity
If two polarizers are used in LCD devices, then light can be modulated by the liquid crystal layer, but the color gamut becomes narrow
Solution Approach 1:
By removing the polarizer configuration, the patent enables the use of a blue backlight source with color film layers to generate a wide color gamut. The absence of polarizers eliminates the spectral filtering that limits color range in traditional LCDs, allowing the blue backlight to excite the color films to produce vibrant red, green, and blue colors that achieve wide color gamut coverage.
Solution Approach 2:
The patent employs a composite structure consisting of a blue backlight source combined with multiple color film layers (red quantum dot layer, green quantum dot layer, blue filter layer). This composite material approach allows the system to convert monochromatic blue light into a wide spectrum of colors, achieving wide color gamut (such as Adobe RGB or DCI P3) without the limitations of traditional polarizer-based LCDs.
3Illumination intensity
If polarizers with less than 50% transmittance are used, then the liquid crystal layer can modulate light, but the overall transmittance of the display device is significantly reduced
Solution Approach 1:
The patent extracts and removes the polarizer component from the display structure, eliminating the transmittance loss inherent in polarizing filters. The new design uses a blue backlight source that directly illuminates the liquid crystal layer and color film layers, achieving high overall transmittance without the need for polarizer integration. This simplifies the manufacturing process by removing the complex polarizer alignment and integration steps.
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 design enhances light transmission efficiency and achieves a wide color gamut without the need for polarizers, improving display performance and color representation.
Implementation Method 1
the liquid crystal layer at least comprises a first liquid crystal layer and a second liquid crystal layer stacked on each other, and a spiral direction of liquid crystal in the first liquid crystal layer is opposite to a spiral direction of liquid crystal in the second liquid crystal layer
Implementation Method 2
the liquid crystal layer reflects a first color light in response to a case where no voltage is applied between the first electrode layer and the second electrode layer
Implementation Method 3
a second color film layer configured to emit a second color light in response to the incident first color light; and a third color film layer configured to emit a third color light in response to the incident first color light
Data Source
AI summary
A display panel and a display device are provided, the display panel includes: a first substrate and a second substrate opposite to each other; a liquid crystal layer between the first substrate and the second substrate; a first electrode layer between the first substrate and the liquid crystal layer; and a second electrode layer between the second substrate and the liquid crystal layer, wherein the liquid crystal layer at least includes a first liquid crystal layer and a second liquid crystal layer stacked on each other, and a spiral direction of liquid crystal in the first liquid crystal layer is opposite to a spiral direction of liquid crystal in the second liquid crystal layer.