To speed up the printing speed of an inkjet printer, the manufacturers normally focus on increasing the droplet frequency response. Hence, it has become a very important technique to measure the droplet frequency response of an inkjet printhead. A magneto-electric method is proposed to measure the droplet frequency response. The magneto-electric apparatus contains a metallic detecting plate and a magnetic ring with a gap of about 100 micrometers filled with a nonmagnetic insulating material. The magnetic ring itself is made of a high-permeability alloy consisting of about 78% nickel and 22% iron. When an ink drop jetted from a nozzle makes a contact with the metallic detecting plate, which is perpendicular to the nozzle plate of a printhead, a current is conducted through the detecting plate immediately, and detected as a portion of expected signal. The expected signal is then processed by a signal processing circuit for counting the number of jetted drops, and determining the maximum droplet frequency response of the inkjet printhead as a function of the driving frequency of an applied voltage across the printhead.

Date Published: 28 June 2000
PDF: 9 pages
Proc. SPIE 4080, Input/Output and Imaging Technolgies II, (28 June 2000); doi: 10.1117/12.389450

Published in SPIE Proceedings Vol. 4080:
Input/Output and Imaging Technolgies II
Yung-Sheng Liu; Thomas S. Huang, Editor(s)