Recently, inkjet-printing industry demands high-speed and single-pass printing that requires simultaneous jetting of a large number of ejectors. As a result, the jetting reliability has become an important issue in most industrial inkjet-printing applications. To ensure the jetting reliability, a real-time monitoring of the jetting status is needed. Since the monitoring process should not interrupt the printing process, the monitoring time for all of the nozzles should be less than 1 second. For this purpose, the authors developed two module prototypes to monitor the commercial inkjet heads with 1024 nozzles: (1) a head driver with an internal self-sensing capability; (2) an external monitoring module that can be used for third-party drivers. To deal with a large number of nozzles effectively, the authors are proposing a parallel sensing scheme that can be used to monitor multi-head jetting. Lastly, the authors verified our monitoring scheme by using a drop visualization system for a comparison of the monitoring results with the droplet jetting images.
Kye-Si Kwon, Jaeryul Yu, Thanh Huy Phung, "Real-Time Jet Failure Detection of Inkjet Heads with 1024 Ejectors" in Journal of Imaging Science and Technology, 2017, pp 050401-1 - 050401-11, https://doi.org/10.2352/J.ImagingSci.Technol.2017.61.5.050401