ALEXANDRIA, Va., June 19 -- United States Patent no. 12,333,086, issued on June 17, was assigned to Primax Electronics Ltd. (Taipei, Taiwan).
"Composite function keyboard circuit" was invented by Yi-Liang Chen (Taipei, Taiwan), Chih-Chen Chang (Taipei, Taiwan) and Chien-Ming Li (Taipei, Taiwan).
According to the abstract* released by the U.S. Patent & Trademark Office: "A composite function keyboard circuit includes a first matrix circuit, a first bias resistor group, a second matrix circuit, a second bias resistor group and a controller. Each switch unit in the first matrix circuit is an ink-type force sensing switch. A resistance of the ink-type force sensing switch is variable according to a pressing mode of a keypress action. An elect...