OLED Edge Adhesive Geometry to Prevent Cover Window Gaps
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing display devices, particularly OLED displays, face issues with image quality due to gaps between the adhesive member and the cover window, leading to visible defects around the edge.
Innovation Solution
A display device design with a specific angle between the side surface and top surface of the adhesive member, along with an adhesive member forming apparatus that includes a guide rail, stage, alignment device, curing device, and inkjet printing, to form intermediate and peripheral adhesive layers, ensuring a flat top surface and improved adhesion, thereby preventing gaps.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the adhesive member is applied to bond the polarizing layer and cover window, then adhesion is achieved, but gaps may form at the edge leading to visible defects
Solution Approach 1:
The patent changes the geometric parameters of the adhesive member by forming it at a specific angle (90-135 degrees) between the side surface and top surface. This parameter modification ensures that the adhesive member extends sufficiently to the edge to bond with the cover window while maintaining a flat top surface, thereby preventing gaps and visible defects without compromising adhesion quality
Solution Approach 2:
The patent addresses the gap formation problem by extending the adhesive member into the edge region in a dimensional sense. By forming the adhesive member at a specific angle, it extends laterally toward the edge while maintaining proper thickness, ensuring coverage in the critical edge region where gaps would otherwise form between the polarizing layer and cover window
2Ease of manufacture
If the adhesive member edge is not flattened, then application is simpler, but gaps form between adhesive member and cover window
Solution Approach 1:
The patent applies preliminary action by forming the adhesive member at a predetermined angle (90-135 degrees) during the adhesive application process itself. This preliminary geometric configuration ensures that when the adhesive member is subsequently bonded, its top surface is already flattened and positioned correctly to prevent gaps with the cover window, eliminating the need for additional edge-flattening steps
3Reliability
If the adhesive member extends to the edge, then adhesion is improved, but the angle between side surface and top surface may be inappropriate causing defects
Solution Approach 1:
The patent precisely controls the geometric parameter of the adhesive member by defining the angle between the side surface and top surface to be within the range of 90-135 degrees. This parameter optimization allows the adhesive member to extend sufficiently to the edge for strong adhesion while maintaining a flat top surface that prevents visible defects, resolving the contradiction between adhesion strength and edge precision
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 enhances image quality by preventing air gaps and improving adhesion, thus eliminating visible defects around the edge of the adhesive member.
Implementation Method 1
a curing device which cures an adhesive member of the substrate
Data Source
AI summary
A display device includes a substrate; a pixel electrode on the substrate; a light-emitting layer on the pixel electrode; a common electrode on the light-emitting layer; an encapsulation layer on the common electrode; a polarizing layer on the encapsulation layer; an adhesive member on the polarizing layer; a cover window on the adhesive member; and a light blocking layer disposed next (adjacent) to the adhesive member, between the polarizing layer and the cover window, wherein an angle defined between a side surface of the adhesive member facing the light blocking layer and a top surface of the adhesive member facing the cover window is 90 degrees to 135 degrees.