Canon Kabushiki Kaisha

Takayuki Murata

Shinichi Omo

Akira Kuronuma

Masahiko Umezawa

Hiroshi Fukui

Hitoshi Nishikori

Yuji Akiyama

Masao Maeda

Yuichiro Suzuki

Hideki Nakanishi

Kazuhisa Kuruma

Kiichiro Takahashi

Hiromitsu Hirabayashi

Hitoshi Sugimoto

Shigeyasu Nagoshi

Atsushi Arai

Miyuki Matsubara

Hiroshi Tajika

Jiro Moriyama

Shuichi Murakami

Norihiro Kawatoko

Yuji Konno

Tetsuya Edamura

Nobuyuki Hirayama

Toshiaki Hirosawa

Yoshinori Nakajima

Shogo Kawamura

Akira Nagatomo

Chikatoshi Okubo

A discharge failure nozzle, which cannot print, can be complemented by a printable discharge nozzle according to a simple, low-cost method capable of a high-speed process. A printing apparatus, which prints by using an inkjet head having nozzle arrays formed by arraying a plurality of nozzles for discharging ink while scanning the inkjet head on a printing medium, includes a storage unit which stores the position of an abnormal nozzle that abnormally discharges ink among the plurality of nozzles arrayed in the nozzle arrays, an assignment unit which assigns data subjected to discharge by the abnormal nozzle to a plurality of normal nozzles positioned near the abnormal nozzle in a nozzle array including the abnormal nozzle in accordance with predetermined priorities, and a control unit which controls to perform assignment of data subjected to discharge by the abnormal nozzle every time column data along the scanning direction are created by a predetermined number of columns.

Printing apparatus, printing method and data processing method for compensating for abnormal nozzles in accordance with priorities

Printing apparatus for assigning data subjected to discharge by an abnormal nozzle in accordance with predetermined priorities

This invention provides a printing head which can prevent an increase in the number of block enable signal lines, and can prevent changes in printing ink density caused by interference due to the relative pressures of nozzles generated in ink discharge, and an image printing apparatus using the printing head. For this purpose, an increase in the number of input signal lines along with an increase in the number of blocks is prevented using a block clock signal or the like instead of a block enable signal as an input signal to the printing head. Three ring counters generate signals having different nozzle driving orders. These signals are selectively used by a ring counter selection signal. Ink is not always discharged from the nozzles in the same output order. This can prevent changes in ink density caused by pressure interference.

Printing head, image printing apparatus using the same, and control method therefor

Disclosed are a printing apparatus and printing method which suppress degradation of the image quality caused by discharge failure complement. In the printing apparatus, virtual data are generated for predetermined dots in a scanning direction on the basis of printing data of a plurality of dots in the scanning direction of an inkjet printhead that are printed by an ink discharge failure nozzle among a plurality of nozzles. The priorities of dots subjected to complementary printing among a plurality of dots within a predetermined adjacent area where the printing data and virtual data are printed are decided on the basis of the printing data and virtual data. A position subjected to complementary printing is decided on the basis of the priorities, printing data, and virtual data. Printing data and virtual data which actually cause ink discharge are so moved as to print at the position. Corrected printing data to be actually printed is generated on the basis of the moved data. Printing is performed by driving the inkjet printhead on the basis of the corrected printing data.

Printing apparatus and method capable of complementary printing for an ink discharge failure nozzle

A printing apparatus and printing method can realize high-quality printing without degrading the quality of a printed image even when a nozzle restriction function is adopted in addition to a discharge failure complement function. In a printing apparatus using an inkjet printhead having a plurality of nozzles, whether the position of an ink discharge failure nozzle exists at or near the end of a nozzle area which is still usable regardless of the use restriction on the nozzles is detected. The use of a nozzle for complementary printing executed with a nozzle positioned near the ink discharge failure nozzle is controlled in accordance with the detection result.

Printing apparatus and printing method

In order to reduce emission noise, a recording apparatus uses a cycle controller to variably control a transmission cycle, when transmitting recording data to the recording head, and a head controller to control the recording head based on the controlled transmission cycle and the recording data. By varying the data transfer cycle of data to the recording head, the recording apparatus of the present invention makes it possible to suppress a rise in radiation noise peak levels due to overlapping of radiation noise spectra, which in turn weakens the strength of the electric field at certain cycles and makes it possible to reduce radiation noise levels.

Recording apparatus

When printing data is to be printed, the number of simultaneously driven printing elements of a plurality of printing elements of a printhead is discriminated. On the basis of the number of simultaneously driven printing elements discriminated and a fundamental pulse width changeably, determined on the basis of driving conditions of the printhead, a driving pulse to be applied to printing elements used in the printing of the printing data is controlled.

Printing apparatus, control method of the apparatus, and computer-readable memory

This invention provides an image print apparatus capable of quickly reducing, with a low-cost arrangement, charges accumulated in a capacitor used for reducing variations in printhead voltage, and a control method thereof. After a head power supply V which supplies power to the printhead is turned off, the print element of the printhead is so driven as not to discharge ink.

Image print apparatus and control method thereof

A printer, which enables complicated printhead controls without a complicated logic circuit, includes a data table showing a control pattern of six controls stored in a RAM. When a drive trigger is inputted into a read-trigger generator, an address generator generates the address of the data table in the RAM as an address signal and inputs the address signal into the RAM. On the other hand, the read-trigger generator inputs a data-read trigger into the RAM. Control signals read by these signals are inputted into a head driver with heat pulses, which drives the printhead.

Printing apparatus

A liquid discharge head comprises a plurality of main discharge ports arranged at predetermined intervals, at least one sub-discharge port arranged in the arrangement direction of the main discharge ports on both end sides of the arrangement direction of main discharge ports at intervals larger than the intervals of the main discharge port arrangement, a plurality of liquid chambers having these plural discharge ports open thereto, a common liquid chamber having these liquid chambers communicated therewith, and liquid being supplied thereto, and a plurality of discharge energy generating units provided for each of the liquid chambers corresponding to the main discharge ports and the sub-discharge ports to generate discharge energy utilized for discharging liquid from the main discharge ports and the sub-discharge ports. With the liquid discharge head thus arranged, bubbles residing on both end portions of the common liquid chamber are exhausted together with liquid thus exhausted from the sub-discharge ports, hence making it possible to effectively prevent drawback, such as color mixture, that may occur when different kinds of liquid enter the interior of liquid discharge head from the sub-discharge ports at the time of executing recovery process of the liquid discharge head which is performed by the overall suction operation.

Liquid discharge head, driving method therefor, and cartridge, and image forming apparatus

A printer and printing control method for improving throughput by performing efficient smoothing processing. The printer adopting the method monitors print data while it is transmitted from a receiving buffer,to a print buffer,analyses the print data by a unit of one scanning area of a printhead whether the print data causes printing operation of the printhead, and, if no print data which causes printing operation is included in the print data corresponding to the one scanning area, controls to skip execution of row-column conversion and/or smoothing processing.

Printer and printing control method

When the sub-heaters of recording heads are PWM controlled in a low-temperature environment, temperatures of the recording heads are respectively detected by temperature sensors. The number of recording heads to be heating controlled is determined from the detected recording head temperatures, and a maximum duty ratio of a pulse train supplied to the sub-heater corresponding to the recording head to be heating controlled is determined in accordance with the determined number of the recording heads, so that supply timings of pulse width controlled pulse trains supplied to the sub-heaters corresponding to the recording heads to be heating controlled are not overlapped.

Ink-jet printer and temperature control method of recording head

A printing apparatus and a print control method for performing H-V conversion and minimum track printing at high speed. When printing is to be performed on a print medium by reciprocally scanning a printhead, image data is externally inputted, vertical and horizontal orientation of the inputted image data is converted with considering the print width of the printhead so that the vertical and horizontal arrays are reversed in a buffer of a DMAC, the outputted result is continuously processed by utilizing a logical circuit, the left and right ends where actual printing operation is performed based on the image data is detected within a scan area of the printhead, and the scan area of the printhead is controlled based on the detection result.

Printing apparatus and printing control method

A data processing method which efficiently performs data transfer by using a data bus with an appropriate access width corresponding to transfer data and a printer using the data processing method. In the printer, a CPU bus 70 having a 16-bit physical bus width, is shared by a CPU 21 and a DMAC 80. In a case where the CPU 21 accesses a memory via the CPU bus 70 with an 8-bit width, while the DMAC 80 accesses the memory via the CPU bus 70 with a 16-bit width, each time the DMAC 80 needs to access the memory, the DMAC 80 issues a DMA request signal to the CPU 21, requiring an exclusive access right for the CPU bus 70. In accordance with the request signal, the CPU 21 delivers the exclusive access right for the CPU bus 70 to the DMAC 80. Then the DMAC 80 controls memory access with the 16-bit width.

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Kanagawa, Japan

Takayuki Murata