Canon Kabushiki Kaisha

Steven Noyes

Akitoshi Yamada

Hiromitsu Hirabayashi

Kazuyuki Masumoto

Akihiko Hamamoto

Takao Aichi

Shinji Kanemitsu

Peter L Cheng

Tetsu Kaneko

A printing system in which it is determined whether the print heads of a printer are effectively aligned and, depending on whether or not the print heads are effectively aligned, one of multiple different printing schemes is selected for controlling printing of a print job, wherein the selected printing scheme for the case when the print heads are not effectively aligned includes controlling printing by directing the printer to use only one selected print head.

Printer control based on head alignment

A printer driver executable in a computer connectable to a driven printer. In response to initiation of a print job, the print driver obtains current status of the printer. Based on the status of the printer, the print driver modifies operational parameters of the printer prior to commencement of the print job, so that the operational parameters are different from default ones of such parameters. In addition, the print driver modifies its own operational sequence based on the printer status, so that the operational sequence of the printer is different from a default sequence without such status information.

Status-based control over printer

Printing on a recording medium by lateral scans of a print head in accordance with print data. Content of print data is determined. Then, the print data is printed either with a first lateral scan process using a critical zone at edges in a lateral scan of the print head for printing, or with a second lateral scan process that does not use the critical zone for printing. The first or second lateral scan process is selected based on the print data. Preferably, the critical zone is sized in correspondence with ramp up non-uniformities of a print carriage on which the print head is mounted, so as to accommodate a distance between a point where print degradation due to speed non-uniformities are noticeable to a point where print degradation due to speed non-uniformities are no longer noticeable. The second lateral scan process preferably is a process in which a predetermined margin is inserted into the first lateral scan process. The second lateral scan process is used if print data for a current scan and print data for a previous scan, in at least the critical zone, are continuous print data, thereby alleviating ripple effects for the continuous data. In a case where the print data for the current scan and the print data for the previous scan are not continuous print data, the print data preferably is printed using the first lateral scan process.

Printer carriage control

A system to produce print data corresponding to a multi-level value of a pixel includes a first determining step to determine a first amount of low-penetration black ink corresponding to the multi-level value, a second determining step to determine a second amount of high-penetration black ink corresponding to the multi-level value and a printing step to print the pixel using the first amount of low-penetration black ink corresponding to the multi-level value and the second amount of high-penetration black ink corresponding to the multi-level value.

Color printing using multiple inks

Improved techniques for measuring misalignment between multiple print heads, or between forward and reverse printing for the same print head. Adverse effects of ink bleeding, paper cockling and other ink ejection effects are reduced by superimposingly printed alignment patterns in which less than all pixels of printed portions of the patterns are filled in. Carriage ringing and overshoot effects are reduced by printing the alignment patterns in multiple passes, and preferably with an offset in carriage starting location for each pass. Improved detection of darkest density regions of the superimposingly printed alignment pattern is obtained through detections based on differences between densities rather than absolute values of measured densities.

Automatic alignment of print heads

A printing system to print bands of print data in a forward direction and in a backward direction. The system includes a step to print print data other than black print data included in the bands of print data using bidirectional printing and a step to print black print data included in the bands of print data using unidirectional printing.

Growing community of inventors

Fountain Valley, CA, United States of America

Steven Noyes