Flexible Display PCB Rear-Side Layout for Narrow Bezels
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing display devices face challenges in minimizing the non-display area while maximizing the display area, particularly due to the rigid handling of base layers and the complexity of separating these layers from support substrates during manufacturing.
Innovation Solution
A display device design where the printed circuit board is arranged on the rear surface of a flexible base layer, with a terminal extending through an opening portion from the display area to the non-display area, connected via a connection line covered by an insulating layer, and a thin-film transistor connected to the display element, allowing for a reduced non-display area and enlarged display area by separating the base layer from the support substrate.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Area of moving object
If the printed circuit board is arranged on the front surface of the base layer, then the connection structure is simplified, but the non-display area increases and the display area decreases
Solution Approach 1:
The printed circuit board is moved from the front surface (2D plane) to the rear surface of the base layer, utilizing the third dimension (depth/thickness) to resolve the spatial conflict between display area and connection structure. This dimensional transition allows the display area to be maximized on the front surface while the connection structure is accommodated on the rear surface without overlapping.
Solution Approach 2:
The connection structure is replicated across multiple layers including the base layer, insulating layer, and pixel circuit layer. This multi-layer copying approach distributes the connection function across different planes, reducing the complexity on any single layer while maintaining overall connectivity.
2Ease of manufacture
If the base layer is made flexible to enable separation from support substrate, then the manufacturing process becomes easier, but handling during manufacturing operations becomes difficult
Solution Approach 1:
The base layer's mechanical properties are made dynamic - it maintains rigidity when attached to the support substrate during manufacturing operations, then becomes flexible when separated. This dynamic state change allows the base layer to adapt its properties based on the operational phase, solving the contradiction between handling ease and separation ease.
Solution Approach 2:
The support substrate acts as an intermediary that provides temporary rigidity to the flexible base layer during manufacturing. This mediator allows the base layer to be handled easily while attached, then enables easy separation when the intermediary is removed, resolving the contradiction between handling and separation requirements.
3Adaptability or versatility
If the terminal extends through the opening portion from the display area to the non-display area, then the connection flexibility is improved, but the manufacturing precision requirement increases
Solution Approach 1:
The terminal connection path is segmented into multiple sections: the terminal in the display area, the terminal extending through the opening portion, and the connection line in the non-display area. This segmentation allows each section to be optimized independently - the opening portion provides flexibility while the other sections maintain manufacturing precision through controlled positioning.
Data Source
AI summary
A display device including a display area and a non-display area further includes a base layer including a first surface and a second surface opposite to the first surface, the base layer having, in the non-display area, an opening portion penetrating the first surface and the second surface; a pad unit including a terminal on the first surface, the pad unit extending from the first surface to the opening portion; a connection line connected to the terminal on the first surface, the connection line extending from the non-display area to the display area; an insulating layer covering the terminal and the connection line; a thin-film transistor including a semiconductor layer on the insulating layer, the thin-film transistor being connected to the connection line; and a display element connected to the thin-film transistor, the display element being in the display area.