US Patent Issued to SCREEN Holdings on Dec. 30 for "Inkjet printing apparatus and head inspection method" (Japanese Inventor)

ALEXANDRIA, Va., Dec. 31 -- United States Patent no. 12,508,829, issued on Dec. 30, was assigned to SCREEN Holdings Co. Ltd. (Kyoto, Japan).

"Inkjet printing apparatus and head inspection method" was invented by Yasushi Oshima (Kyoto, Japan).

According to the abstract* released by the U.S. Patent & Trademark Office: "A controller for an inkjet printing apparatus outputs a test drive signal for printing a test pattern to a piezoelectric element of a head. The test drive signal includes a first frequency corresponding portion in which first and second waveforms are combined in a first ratio, and a second frequency corresponding portion in which the first and second waveforms are combined in a second ratio different from the first ratio. Thi...