A novel vision-based approach for high-speed jetting status monitoring of a multi-nozzle inkjet head

Abstract

Multi-nozzle inkjet printing technology has attracted extensive attention in the manufacturing processes of various industrial fields due to its high throughput capability for mass production. However, a high defect rate caused by some abnormal nozzles is a major challenge in the application of this technology. Hence, monitoring the jetting status of all nozzles in multi-nozzle inkjet heads and detecting abnormal nozzles have become an important issue in most inkjet-based manufacturing processes. In this study, we proposed a novel vision-based approach for efficient and fast jetting status monitoring of a multi-nozzle inkjet head. The proposed approach utilizes a continuous scanning mechanism based on a variable pulse width triggering technique, enabling seamless and uninterrupted monitoring. Experimental results demonstrated that our proposed approach could monitor an industrial multi-nozzle inkjet head with 1024 nozzles in just 9.2 s while maintaining measurement accuracy of 99 %. Compared with the conventional method, the proposed approach could improve monitoring speed by 44.8 times and shorten the monitoring time by 97.8 %. To demonstrate the practicality of the proposed approach, in-house jetting status monitoring software was also developed, which can monitor and evaluate the jetting status of the whole nozzle in real-time. Overall, this study provides strong technical support for quality control of multi-nozzle inkjet printing technology and would help expedite the entire manufacturing process, improve manufacturing yield, and reduce production costs in the inkjet-based manufacturing process.