OLED Bus and Branch Line Segmentation for OS Test Accuracy
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In the manufacturing of OLED display devices, performing an open- and short (OS) test to detect unintended circuits is challenging due to the difficulty in distinguishing differences in resistance measurements, as the resistance of bus lines can interfere with the measurements of branch lines, affecting the accuracy and efficiency of the test.
Innovation Solution
The OLED display device incorporates a bus line and a branch line that are substantially separated before and during the OS test, allowing for easier detection of unintended shorts or opens by ensuring the resistance of the bus line does not affect the measured resistance of the branch line, with a connection member electrically connecting them after the test.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the bus line and branch line are electrically connected during the OS test, then the electrical continuity is maintained for functional operation, but the resistance measurement accuracy deteriorates due to interference from the bus line resistance
Solution Approach 1:
The connection conductor set is divided into a bus line connection conductor set and a branch line connection conductor set that are separated from each other. This segmentation allows the bus line and branch line to be electrically isolated during OS testing, enabling accurate resistance measurements without interference from the bus line resistance, while maintaining electrical continuity through the connection conductors during normal operation.
Solution Approach 2:
The connection conductor set acts as an intermediary between the bus line and branch line. By introducing this intermediate connection structure with separate connection conductor sets, the patent enables controlled electrical connection during normal operation while allowing physical separation for accurate OS testing, thus mediating between the conflicting requirements of continuity and measurement accuracy.
2Measurement precision
If the bus line and branch line are separated physically, then the resistance measurement accuracy is improved, but the device complexity increases due to additional connection structures
Solution Approach 1:
The bus line connection conductor set and branch line connection conductor set are merged into a single integrated connection structure that is formed simultaneously with the bus line and branch line using the same thin film deposition process. This merging approach reduces device complexity by eliminating the need for separate connection structures and additional manufacturing steps, while still enabling accurate OS testing through the inherent separation of the connection conductor sets.
3Ease of manufacture
If the OS test is performed with both bus line and branch line connected, then the manufacturing process is simplified, but the detection capability deteriorates due to inability to distinguish unintended shorts from normal resistance variations
Solution Approach 1:
The OS test is performed on the branch line before the interconnection conductor is formed to connect the bus line and branch line. This preliminary action allows the detection of unintended shorts or opens in the branch line before the connection is established, enabling accurate measurement without interference from the bus line resistance. After the OS test, the interconnection conductor is formed to complete the electrical connection for functional operation.
Data Source
AI summary
A display device may include a display area for displaying an image. The display device may further include a peripheral area that surrounds the display area. The display device may further include a pixel disposed in the display area. The display device may further include a bus line disposed in the peripheral area and configured to transmit a signal. The display device may further include a connection conductor set electrically connected to the bus line. The display device may further include a branch line electrically connected to the connection conductor set, configured to receive the signal from the bus line, and configured to transmit the signal to the pixel, wherein a portion of the branch line is disposed in the display area.