Dual mode ink jet printer

Abstract

In the embodiments of the invention described in the specification, a four-color ink jet printer includes a transport mechanism for conveying a record medium in one direction and an ink jet head containing a black ink nozzle array and a primary color ink nozzle array for scanning the record medium in a transverse direction while projecting drops of ink onto the record medium. A control unit provides two printing speeds in which either high-quality or high-speed printing can be accomplished. For high-speed printing all of the nozzles of both arrays are used, and for high-quality printing one-third of the nozzles in the black ink array and all of the nozzles in the primary color ink nozzle array are used and the record medium is transported at one-third the rate used for high-speed printing. In certain embodiments, the two arrays of nozzles are disposed at different angles with respect to the scanning motion of the ink jet head so that the nozzles of the primary color array are spaced in the direction of motion of the record medium by a greater distance than the nozzles of the black ink array. In other embodiments, the arrays are disposed at the same angle with respect to the scanning motion and the nozzles for the three primary colors may be alternated in the color nozzle array.

Dependencies are inferred from the claim text.