Segmented Polarizer for Organic EL Display Reflection Suppression
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Organic electroluminescence (EL) display devices face a trade-off between suppressing external light reflection and maintaining high luminance, as existing solutions like circular polarization plates reduce visible light transmittance, leading to lower luminance.
Innovation Solution
An organic EL display device configuration featuring a light emitting layer with multiple color layers and an optically anisotropic layer, combined with a pattern polarizer having regions with specific transmittance levels for each color, allowing for high luminance while effectively suppressing external light reflection.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If a circular polarization plate is used to suppress external light reflection, then the reflection suppression effect is improved, but the visible light transmittance decreases to 40-50%, reducing luminance
Solution Approach 1:
The polarizer is divided into multiple polarization regions (first, second, third polarization regions) corresponding to different color light emitting layers. Each region has optimized transmittance characteristics for its corresponding color, allowing selective transmission that maintains overall luminance while suppressing external light reflection.
Solution Approach 2:
Different polarization regions are assigned different transmittance characteristics tailored to their specific function. The first polarization region has transmittance ≥60% for first color light, the second for second color light, and the third for third color light, creating local optimization that resolves the global contradiction between reflection suppression and luminance maintenance.
2Ease of manufacture
If layers with different refractive indexes are laminated on the electrode, then the device structure is formed, but external light is reflected at interfaces causing contrast reduction and reflected glare
Solution Approach 1:
The optically anisotropic layer serves as an intermediary between the light emitting layer and the polarizer. This intermediate layer helps manage light transmission and polarization, working in conjunction with the segmented polarizer to reduce interface reflections while maintaining structural integrity.
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 high luminance while maintaining excellent external light reflection suppression, improving the overall performance of organic EL display devices by optimizing light transmittance and reflection management.
Implementation Method 1
an optically anisotropic layer
Implementation Method 2
a polarizer having two or more predetermined regions of which a transmittance is changed
Implementation Method 3
the effect of suppressing external light reflection is high
Data Source
AI summary
An object of the present invention is to provide an organic EL display device having high luminance while maintaining an excellent effect of suppressing external light reflection. The organic electroluminescence display device of the present invention includes a polarizer, an optically anisotropic layer, and a light emitting layer in this order, in which the light emitting layer includes at least a plurality of first light emitting layers that emit a first color light, a plurality of second light emitting layers that emit a second color light, and a plurality of third light emitting layers that emit a third color light, on the same plane, and the polarizer has at least two regions selected from the group consisting of a first polarization region in which a transmittance of the first color light emitted from the first light emitting layer is greater than or equal to 60% and an average visible light transmittance is 30% to 55%, a second polarization region in which a transmittance of the second color light emitted from the second light emitting layer is greater than or equal to 60% and an average visible light transmittance is 30% to 55%, and a third polarization region in which a transmittance of the third color light emitted from the third light emitting layer is greater than or equal to 60% and an average visible light transmittance is 30% to 55%.