Active Matrix Substrate Chamfer for Narrow Frame Display
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional active matrix display devices face challenges in minimizing the frame area due to the increased length and resistance of lead wirings, which hinder the downsizing of display devices and the formation of larger display regions.
Innovation Solution
The formation of a chamfer portion at the end of the active matrix substrate allows for the use of a common wiring to electrically connect the wirings, reducing the frame area by substituting for lead wirings and enabling a thicker film thickness to lower wiring resistance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the width of lead wirings is increased to reduce wiring resistance, then the wiring resistance is reduced, but the area of the frame portion is increased
Solution Approach 1:
The patent transitions from planar wiring layout to three-dimensional wiring structure by forming lead wirings in multiple layers (first lead wiring layer and second lead wiring layer) and using vertical connection portions to connect between layers. This vertical dimension allows reduced horizontal wiring width while maintaining electrical connectivity, thereby reducing frame area without compromising wiring resistance.
Solution Approach 2:
The patent divides the lead wiring into multiple segments across different layers and uses connection portions to join them. The first lead wiring extends from the pixel portion to a first connection portion, the second lead wiring extends from the first connection portion to a second connection portion, and vertical connection portions link these segments. This segmentation allows optimized routing that minimizes frame area while maintaining low resistance.
2Ease of operation
If the length of lead wirings is increased to connect peripheral components, then the electrical connection is achieved, but the wiring resistance is increased
Solution Approach 1:
By utilizing vertical dimensions through multiple wiring layers and connection portions, the patent creates shorter horizontal wiring paths while achieving the same electrical connection function. The three-dimensional routing reduces the effective length of wirings compared to conventional planar designs, thereby reducing resistance.
Solution Approach 2:
The patent employs different conductive materials for different wiring layers - the first lead wiring uses a first conductive material and the second lead wiring uses a second conductive material, with connection portions using a third conductive material. This composite approach allows optimization of each segment's resistance based on material properties while achieving overall low resistance.
Data Source
AI summary
It is an object of the present invention to provide a display device where expansion of a frame portion over a substrate, which results from formation of a lead wiring over an active matrix substrate, is minimally suppressed to realize a narrow frame. According to one feature of a display device of the present invention, a chamfer portion is formed at least at an end portion of an active matrix substrate having a pixel portion of a pair of substrates disposed to be opposed to each other, and wirings (a source line, a gate line, a storage capacitor line, a leading out wiring, and the like) over the active matrix substrate are electrically connected by a common wiring formed in the chamfer portion.