OLED Protective Film Wrapping for Crack Resistance and Light Extraction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional OLEDs suffer from low out-coupling efficiency due to total reflection and are prone to cracking, especially at the glass substrate interfaces, which limits their performance and reliability.
Innovation Solution
An organic luminance device structure incorporating a base substrate with an organic multi-layered structure, a cover substrate, and a protective film that wraps the light emitting and lateral surfaces, using an elastic optical silicone film doped with refractive index-mismatching dopants to enhance light extraction and prevent cracking.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If a conventional OLED assembly structure is used, then the device is simple to manufacture, but the out-coupling efficiency is low (only 10-20%) due to total reflection at the glass substrate interface
Solution Approach 1:
The patent introduces an intermediate layer (prism layer or microlens array layer) between the OLED structure and the cover glass substrate. This intermediary structure modifies the optical path and reduces total internal reflection, thereby improving light extraction efficiency without fundamentally changing the manufacturing process
Solution Approach 2:
The patent modifies the refractive index parameters by introducing materials with different optical properties (prism structures, microlenses) to change the critical angle and reduce total internal reflection at the glass-air interface, thereby improving out-coupling efficiency
2Stability of the object's composition
If the base substrate size is made larger than the cover substrate, then the OLED assembly structure is stable, but the exposed portion of the base substrate is prone to cracking during assembling, conveying or use
Solution Approach 1:
The patent introduces a flexible buffer layer (such as a thin film layer) around the exposed portion of the base substrate. This flexible layer absorbs stress and prevents crack propagation during assembly and handling, while maintaining the structural stability provided by the larger base substrate
Solution Approach 2:
The patent applies a protective buffer layer in advance around the exposed substrate edges before assembly. This cushioning layer pre-compensates for potential stress concentrations that would occur during handling and assembly, preventing cracks before they can form
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 significantly increases out-coupling efficiency by up to 50% and enhances cracking resistance, ensuring improved performance and durability of the OLEDs.
Implementation Method 1
While the light is traveling out of the glass substrate 1 into the air, the total reflection phenomenon would occur in the interface. In general, the total reflection phenomenon comes up when the light travels from a high refractive index medium into a low refractive index medium such as air.
Implementation Method 2
the light travels from a high refractive index medium into a low refractive index medium such as air
Implementation Method 3
The prefer embodiment in this invention is to choose an elastic optical silicone film doped with a dopant as the protective film.
Data Source
AI summary
An organic luminance device includes a base substrate, a organic luminance multi-layered structure and a cover substrate. Furthermore, a protective film is used to wrap the light emitting surface and at least one lateral surface of the base substrate to prevent the substrate from crack. The protective film may be doped with one or more dopants having a refractive index different from original material of the protective film.