Refractive Layer Design for Display Light Extraction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current display apparatuses face challenges in achieving high light extraction efficiency and visibility, particularly in providing high-quality images due to limitations in light management layers.
Innovation Solution
The implementation of a refractive layer with different refractive indices and a light blocking layer on the lower surface of an encapsulation substrate, where the refractive layer includes a first insulating layer with a lower refractive index and a second insulating layer with a higher refractive index, arranged to correspond to emission and non-emission areas respectively, along with a light blocking layer that includes openings for improved light output and reduced external light reflection.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Illumination intensity
If a conventional encapsulation substrate is used without additional light management layers, then the device structure remains simple, but light extraction efficiency and visibility are insufficient
Solution Approach 1:
The light management function is segmented into two distinct layers: a refractive layer with multiple insulating layers having different refractive indices for light extraction enhancement, and a light blocking layer for controlling light paths. This segmentation allows each layer to perform its specific function optimally while contributing to overall light extraction efficiency without requiring a single complex structure
Solution Approach 2:
Different insulating layers within the refractive layer are positioned with specific refractive indices matched to local requirements: the first insulating layer (lower refractive index) corresponds to non-emission areas for reducing light leakage, while the second insulating layer (higher refractive index) corresponds to emission areas for enhancing light extraction. This local quality approach optimizes light management in different regions independently
2Object-affected harmful factors
If external light reflection is not controlled, then the device structure remains simple, but visibility and image quality deteriorate
Solution Approach 1:
The light blocking layer, which may initially seem to block useful light, is strategically designed with openings that correspond to emission areas. This converts the potentially harmful effect of light blocking into a beneficial function by preventing external light reflection in non-emission areas while maintaining light output in emission areas, thereby improving visibility and image quality
Solution Approach 2:
The light blocking layer is positioned below the encapsulation substrate to preemptively block external light before it can reflect off internal structures and interfere with display visibility. This preliminary action prevents harmful reflections before they occur, improving image quality without requiring additional complex anti-reflection coatings on the front surface
3Illumination intensity
If polarizing films are used to improve visibility, then image quality improves, but power consumption increases and device complexity increases
Solution Approach 1:
The patent extracts the light management function from the conventional approach that relies on polarizing films and instead implements dedicated refractive and light blocking layers. This extraction eliminates the need for polarizing films while achieving the same visibility improvement through refractive index matching and strategic light path control, thereby reducing power consumption associated with polarizing film requirements
Solution Approach 2:
The invention changes the optical parameters by using insulating layers with specifically selected refractive indices (lower refractive index for non-emission areas, higher refractive index for emission areas) to optimize light extraction efficiency. This parameter-based approach replaces the need for polarizing films, reducing both device complexity and power consumption while maintaining improved visibility
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 configuration enhances light extraction efficiency and visibility by optimizing light path refraction and reducing external light interference, thereby improving the overall image quality without the need for a polarizing film, leading to increased luminance and reduced power consumption.
Implementation Method 1
a refractive layer on a lower surface of the encapsulation substrate, the refractive layer including a first insulating layer having a first refractive index and a second insulating layer having a second refractive index greater than the first refractive index
Implementation Method 2
a light blocking layer on a lower surface of the refractive layer
Data Source
AI summary
A display apparatus includes: a display substrate; a plurality of display elements provided on the display substrate and which emit light; an encapsulation substrate provided on the display elements to face the display substrate; a refractive layer provided on a lower surface of the encapsulation substrate, the refractive layer including a first insulating layer having a first refractive index and a second insulating layer having a second refractive index greater than the first refractive index; and a light blocking layer provided on a lower surface of the refractive layer. The first insulating layer and the light blocking layer are arranged to correspond to non-emission areas between the display elements. The second insulating layer is arranged to correspond to emission areas of the display elements. A width of an upper surface of the second insulating layer is less than a width of a lower surface of the second insulating layer.