EP0390473A2 - Appareil d'enregistrement à jet d'encre - Google Patents

Appareil d'enregistrement à jet d'encre Download PDF

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Publication number
EP0390473A2
EP0390473A2 EP90303207A EP90303207A EP0390473A2 EP 0390473 A2 EP0390473 A2 EP 0390473A2 EP 90303207 A EP90303207 A EP 90303207A EP 90303207 A EP90303207 A EP 90303207A EP 0390473 A2 EP0390473 A2 EP 0390473A2
Authority
EP
European Patent Office
Prior art keywords
image
edge
recording
ink jet
colour
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
EP90303207A
Other languages
German (de)
English (en)
Other versions
EP0390473A3 (fr
EP0390473B1 (fr
Inventor
Hisashi Fukushima
Nobuhiko Takekoshi
Akio Suzuki
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Canon Inc
Original Assignee
Canon Inc
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Canon Inc filed Critical Canon Inc
Publication of EP0390473A2 publication Critical patent/EP0390473A2/fr
Publication of EP0390473A3 publication Critical patent/EP0390473A3/fr
Application granted granted Critical
Publication of EP0390473B1 publication Critical patent/EP0390473B1/fr
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
    • B41J—TYPEWRITERS; SELECTIVE PRINTING MECHANISMS, i.e. MECHANISMS PRINTING OTHERWISE THAN FROM A FORME; CORRECTION OF TYPOGRAPHICAL ERRORS
    • B41J2/00—Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed
    • B41J2/005—Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed characterised by bringing liquid or particles selectively into contact with a printing material
    • B41J2/01—Ink jet
    • B41J2/21—Ink jet for multi-colour printing
    • B41J2/2132—Print quality control characterised by dot disposition, e.g. for reducing white stripes or banding
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
    • B41J—TYPEWRITERS; SELECTIVE PRINTING MECHANISMS, i.e. MECHANISMS PRINTING OTHERWISE THAN FROM A FORME; CORRECTION OF TYPOGRAPHICAL ERRORS
    • B41J2202/00—Embodiments of or processes related to ink-jet or thermal heads
    • B41J2202/01—Embodiments of or processes related to ink-jet heads
    • B41J2202/12—Embodiments of or processes related to ink-jet heads with ink circulating through the whole print head

Definitions

  • the present invention relates to an ink jet recording apparatus having a plurality of recording head.
  • An ink jet recording apparatus for recording images wherein ink or another coloring agent is ejected on a recording material to form the images.
  • the ink jet recording apparatus becomes widely used because of the advantages that the noise is small because it is non-impact type and that color image recording is easy using various color inks and other advantages.
  • the ink jet recording apparatus comprises a recording material 5 in the form of a roll, recording material conveying rollers 1 and 2, a feeding roller 3 which is driven by a sub-scanning motor 50 to be fed in a direction indicated by an arrow f.
  • a recording material 5 in the form of a roll
  • recording material conveying rollers 1 and 2 a feeding roller 3 which is driven by a sub-scanning motor 50 to be fed in a direction indicated by an arrow f.
  • guide rails 6 and 7 are extended in parallel on which a recording head unit 9 is carried on a carriage for main-scanning movement.
  • the carriage 8 has four color recording heads 9Y, 9M, 9C, 9BK for yellow, magenta, cyan and black colors. They are connected for the four color ink containers, respectively.
  • the recording material 5 is intermittently fed by the amount corresponding to the printing width of the recording head 9.
  • Figures 12A and 12B schematically show the overlapping of the ink layers at the instance when the second line image is printed before the first color image is not dried.
  • Figure 12A is a top plan view
  • Figure 12B is a sectional view taken along a chain line of Figure 12A.
  • FIGs 12A and 12B From the state shown in Figures 12A and 12B, both of the first color ink and the second color ink are evaporated and absorbed into the recording sheet.
  • Figures 13A and 13B show schematically the state wherein the first color and the second color are mixed. That is, before the first ink is not dried, the second ink is overlaid thereon, and therefore, as shown in Figure 13B, the second ink flows outside, so that the edges of the line is blurred by the mixture of the first color and the second color, as shown in Figure 13A.
  • FIG. 1 is a sectional view of an ink jet recording apparatus according to an embodiment of the present invention.
  • the apparatus comprises a scanner 301 for reading an original and converting the outputs thereof to electric signals.
  • the output of the scanner is supplied as a driving signal to a recording head 305 of a printer 302.
  • a sheet feeder 303 accommodates recording sheet (recording material) and is effective to feed the recording sheets one-by-one to a belt conveyer 304.
  • the recording sheet is imparted the printing by the recording head 305 while it is conveyed by the belt conveyer 305. It is discharged to a tray 420 through an image fixing and discharging station 307.
  • the apparatus further comprises a recovery gap 306 to maintain the recording head 305 in a printable state.
  • an original 401 is scanned by an original scanning unit 402.
  • the original scanning unit 402 contains a unit magnification color separation line sensor (color image sensor) 404, a rod array lens 403 and an exposure lamp 405.
  • an exposure lamp 405 in the original scanning unit 402 is turned on, by which the light reflected by the original 401 is guided by the rod array lens 403 to be concentrated on the unit magnification color separation line sensor which is a color image reading sensor.
  • the color image information on the original is read for each of the color components, and the read is converted to electric digital signals.
  • the digital signal is transmitted to an unshown image discriminator, where the discrimination is made as to whether the region of the image is a character portion having edges, solid high density portion or another portion.
  • the recording head used in the ink jet recording apparatus includes fine liquid ejection outlets (orifices), liquid passages, energy applying portions disposed on a part of liquid passages, and energy generating means for generating liquid droplet forming energy to the liquid at the energy applying portion.
  • the energy generating means for generating such energy there are electromechanical transducer such as a piezoelectric element, a liquid produce heat, by which the liquid droplet is ejected, and an electrothermal transducer for heating the liquid to eject it.
  • electromechanical transducer such as a piezoelectric element
  • a liquid produce heat by which the liquid droplet is ejected
  • an electrothermal transducer for heating the liquid to eject it.
  • the recording head using the thermal energy is advantageous in that the liquid outlets (orifices) for ejecting liquid droplets can be disposed at a high density, and therefore, a high resolution recording is possible.
  • Recording head using the electrothermal transducers as the energy generating means can be reduced in its size, and in addition, the advantages of IC technique or microprocessing technique which are recently remarkably improved in the semiconductor manufacturing field can be used to a great extent. Furthermore, it can be easily produced in the form of an elongated head or a two dimensional head. Therefore, it is easy to produce it in a multi-­nozzle-high density head. In addition, it can be mass-­produced at low manufacturing cost.
  • the ink jet recording head using the electrothermal transducer as the energy generating means and produced through a semiconductor manufacturing process generally has liquid passages corresponding to the respective orifices, wherein the thermal energy is applied to the liquid filling the liquid passages by the electrothermal transducers to eject the liquid through the orifice.
  • a common chamber is provided to supply the liquid to the respective liquid passages.
  • Figure 9 shows a general arrangement of the ink jet recording head which comprises an electrothermal transducer 103 formed as a film on a substrate 102 through a semiconductor manufacturing process including an etching step, an evaporation step or a sputtering step, electrodes 104, nozzle walls 105 and a top plate 106.
  • Recording liquid 112 is supplied into a common chamber 108 of the recording head 101 from an unshown liquid container through a liquid supply pipe 107.
  • Designated by a reference 109 is a connector for supplying the liquid.
  • the liquid 112 supplied into the common chamber 108 is supplied into the nozzle 110 by capirally action, and is retained there by formation of a meniscus at the orifice of the nozzle end.
  • the liquid on the electrothermal transducer is heated, by which a bubble is produced.
  • the bubble formation energy a liquid droplet is ejected through the orifice 111.
  • Figure 8 shows the structures of an elongated recording head having multi-nozzles and an ink supply means.
  • the recording head 1 comprises a common chamber 52 and liquid ejection outlets (orifices) 53 arranged in the recording liquid ejection surface 54.
  • the number of the ejection outlets 53 is enough to cover the width of the recording material.
  • the ink supply system includes a recording liquid supply container for supplying the recording liquid to the recording head 1, a main container 56 for supplying the recording liquid to the container 55, wherein the recording liquid is supplied from the container 55 through the supply pipe 57 to the common chamber 52 of the recording head.
  • the recording liquid can be supplied into the supply container 5 from a main container 56 through a one-way replenishing valve 58 by a recovery pump 59.
  • the system further comprises a one-way valve used for a recovery operation for recovering the function of the recording head 1, a circulation pipe 61 in which the recovery valve 10 is mounted, an electromagnetic valve 62 in the first supply pipe 57 described above, and an air vent valve 63 for the supply container.
  • the electromagnetic valve 62 is opened during the recording operation, so that the recording liquid is supplied into the common chamber 52 by the weight of the liquid from the supply tank 55, and is fed to the orifice 53 from the chamber 52 through an unshown liquid passage.
  • the recovery pump 59 is operated to supply the recording liquid into the common chamber 52 through the circulation pipe 61, by which the recording liquid is supplied from the common chamber 52 through the first supply pipe 57 back to the supply container 55, thus circulating the liquid.
  • the electromagnetic valve 62 is closed, and the recording liquid is forcedly supplied into the common chamber 52 through the circulation pipe 61 by the pump 59, by which the air bubble or bubbles are discharged, and the recording liquid is discharged through the orifice 53.
  • the recording sheet used as the recording material is closely contacted and retained on the conveyer belt 61 electrically charged by a corona discharging means 606, and is conveyed by the rotation of the driving roller 602.
  • the gap between the ejecting surface and the recording sheet is maintained by contact of pins 616.
  • the recording sheet passes below the recording head 110C, 110M, 110Y and 110BK, the printing operation in the respective colors are performed, so that cyan image, magenta image, yellow image and the black images are printed in the order named.
  • the recording sheet discharged from registration rollers 415 and 416 is conveyed along the guide plate 600 to the conveyer belt 601.
  • the conveyer belt 601 has a two layer structure including an insulating layer, at the recording paper side, having a volume resistivity of not less than 1012 ohm.cm, and a conductive layer, at the opposite side, having a volume resistance of not more than 108 ohm.cm.
  • the conveyer belt 601 is stretched around the driving roller 602, the follower roller 605 and tension rollers 604 and 605 by a tension force of 2 - 5 kg. It is moved in the direction A by a motor (not shown) coupled with the driving roller 602.
  • the recording paper is carried on the conveyer belt 601 immediately before the conductive roller 607. At this time, the surface of the conveyer belt 601 is charged by a charger 606 to a potential of from several hundreds to several thousands V.
  • a charger 606 When the recording sheet carried on the conveyer belt 601 reaches a grounded conductive roller 607, an electrostatic attraction force is produced between the recording paper and the conveying belt 601 so that the recording paper is retained closely on the conveyer belt 601. With this state maintained, the transfer material reaches the printing station 608.
  • the printing station comprises a head block 660, printing heads 110C, 110M, 110Y and 110BK, a platen 615, pins 616, a spring 617 and guide pin 618.
  • the clearance between the printing head 110C, 110M, 110Y and 110BK and the printing surface of the recording paper is preferably maintained within 100 microns difference from a predetermined set clearance. Therefore, the platen 615 has a surface flatness of several tens microns at its surface contactable to the conveyer belt 601 so that the conveyer belt 601 constitute a flat surface at the printing station 608.
  • the printing head 110C, 110M, 110Y and 110BK are precisely positioned by the head block 660 so that the surface flatness of the surface constituting all of the orifice surfaces of the heads is approximately several tens microns.
  • the platen 615 is provided with pins 616 for the positioning.
  • the platen 615 When the platen 615 is upwardly urged toward the head block 660 by the spring force of the spring 617 along the guide pin 618, the top of the pin 616 abuts the head block 660, by which a clearance 1 for permitting passage of the recording paper is provided.
  • the clearance accuracy between the printing surface of the recording paper at the printing station 608 and the orifice surfaces of the heads is maintained within 100 microns with respect to a predetermined set clearance, since the recording paper is closely contacted on the conveyer belt 601 by the electrostatic force.
  • the recording paper passes through the printing station 608, by which respective color images are printed thereon by the printing heads 110C, 110M, 110Y and 110BK. If the variation in the speed of the conveyer belt 601 large, the printing position by the respective heads are deviated with the result of color deviation or non-uniform color images. In order to prevent this, the accuracy of the thickness of the conveyer belt 601, eccentricity of the driving roller 602, rotational accuracy of the driving motor or the like are determined so that the speed variation of the conveyer belt 601 is sufficiently small.
  • the surface of the conveyer belt 601 is cleaned by a cleaner 620 having an ink absorbing material 619.
  • the ink absorbing material 619 is made of continuous porous material such as polyvinyl formal resin or the like. The absorbed ink flows externally through an outlet 62 and is collected.
  • FIG 11 is a block diagram of a control system for the ink jet recording apparatus of this embodiment.
  • the control system comprises a control circuit 800 including a microcomputer, memory means 801 - 804 for storing image data covering one page of each of cyan, magenta, yellow and black image components, and image feature extractors 805, 806, 807 and 808 for discriminating whether a part of the image around a noted image portion in the one page image data stored in each of the memory means 801 - 804 is a high density solid image or an edge image.
  • the image feature extractors 805 - 808 supply the results of discrimination to the control circuit 800.
  • Figure 2 is a flow chart showing the operation of the control in this embodiment.
  • the quantity of the liquid for the high density image is reduced at the position corresponding to the edge.
  • the image data for one original page read by an unshown reading station are separated into cyan, magenta, yellow and black color components and are stored in the memory means 801 - 804.
  • the control circuit 800 discriminates whether the color component image is solid image or not (S2) in a predetermined region about a noted image portion. If it is not the solid image, the normal printing operation is performed in the color (S8). If it is the solid image, the discrimination is made as to whether or not the subsequent image or images have an edge or edges (S4). If not, the step S8 is executed, by which the normal printing operation is carried out. If there is an edge, the low quantity (density) printing is executed S6.
  • the control is effected to the cyan, magenta, yellow heads with the delay of time corresponding to the time required for the movement between the heads.
  • Figures 3A and 3B the overlapping of the ink layers when the high density solid image (background of the line image and having the second color) is printed at low density.
  • both of the first color ink and the second color ink are evaporated and absorbed into the paper.
  • Figures 4A and 4B show the mixed state of the second color ink and the first color ink.
  • the ink at the edge of the line image does not overflow, and therefore, the edge is not blurred.
  • This embodiment is particularly effective when the ink absorption into the recording material is small as in the case of an OHP (overhead projector) recording material and when the drying speed of the ink in the first ink layer is relatively long.
  • the line image is printed on a high density solid image, but the present invention is applicable where the solid image and a line image are overlaid, and therefore, it is effective when the solid image is printed on a line image.
  • the number of print dots for the high image density solid image is reduced in the high density solid image portion, by which the quantity of the ink is reduced.
  • the quantity of the printing ink is reduced by reducing the size of the dot in the high density solid image portion in the extracted area.
  • Figure 6 shows the algorithm thereof.
  • a means for printing with the smaller dot only in the extracted region is, for example, means for reducing the electric energy supplied to the electrothermal transducer of the ink jet recording head shown in Figure 9. By doing so, finer quantity control than the number of dot reducing process becomes possible, so that an optimum image can be provided easily.
  • a head 1B containing a second color image blue provided by the mixture of the cyan and the magenta, in this embodiment.
  • a second color image blue provided by the mixture of the cyan and the magenta, in this embodiment.
  • the second color ink is used, by which the quantity of the ink per unit area can be reduced down to one half. In this manner, the edge of the second color line image is not blurred, and the printed color in the second color is stabilized.
  • an image having an edge and a high density image are mixed, the blurness of an edge of a line image where the colors are mixed can be prevented by reducing the quantity of the ink printed in the high density image at the position corresponding to the edge or the periphery of the edge.

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  • Engineering & Computer Science (AREA)
  • Quality & Reliability (AREA)
  • Ink Jet (AREA)
  • Particle Formation And Scattering Control In Inkjet Printers (AREA)
  • Ink Jet Recording Methods And Recording Media Thereof (AREA)
EP19900303207 1989-03-29 1990-03-27 Appareil d'enregistrement à jet d'encre Expired - Lifetime EP0390473B1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP74916/89 1989-03-29
JP1074916A JP2752421B2 (ja) 1989-03-29 1989-03-29 インクジェット記録装置

Publications (3)

Publication Number Publication Date
EP0390473A2 true EP0390473A2 (fr) 1990-10-03
EP0390473A3 EP0390473A3 (fr) 1991-04-10
EP0390473B1 EP0390473B1 (fr) 1994-07-06

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EP19900303207 Expired - Lifetime EP0390473B1 (fr) 1989-03-29 1990-03-27 Appareil d'enregistrement à jet d'encre

Country Status (3)

Country Link
EP (1) EP0390473B1 (fr)
JP (1) JP2752421B2 (fr)
DE (1) DE69010367T2 (fr)

Cited By (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0536971A1 (fr) * 1991-10-07 1993-04-14 Hewlett-Packard Company Procédé pour atteindre approximativement la résolution complète d'une impression en couleurs
EP0585521A1 (fr) * 1992-09-03 1994-03-09 Hewlett-Packard Company Amélioration des bordures de couleur d'une imprimante électrostatique multicolore
EP0590848A1 (fr) * 1992-09-30 1994-04-06 Hewlett-Packard Company Méthode pour contrôler la variation de couleur pour des imprimantes à jet d'encre
EP0596373A2 (fr) * 1992-10-30 1994-05-11 Canon Kabushiki Kaisha Appareil et méthode de production d'une image noire dans laquelle l'encre noire recouvre l'encre de couleur
EP0645247A1 (fr) * 1993-09-28 1995-03-29 Canon Kabushiki Kaisha Appareil d'enregistrement à jet d'encre et procédé pour pouvoir empêcher les barbouillages d'encre en amincissant les points d'encre
EP0645246A1 (fr) * 1993-09-24 1995-03-29 Canon Kabushiki Kaisha Appareil à jet d'encre et méthode d'enregistrement
EP0636482A3 (fr) * 1993-07-30 1995-05-03 Canon Kk Dispositif et méthode d'impression à jet d'encre.
AU675221B2 (en) * 1992-07-24 1997-01-30 Canon Kabushiki Kaisha Ink jet recording method employing ink of different characteristics and apparatus therefor
US5731823A (en) * 1994-01-27 1998-03-24 Hewlett-Packard Company Automatic optimization of hardcopy output for enhanced appearance and throughput
EP0779159A3 (fr) * 1995-12-14 1998-06-10 Mitsubishi Denki Kabushiki Kaisha Imprimante à jet d'encre
EP0687565A3 (fr) * 1994-06-17 1998-09-16 Canon Kabushiki Kaisha Méthode d'enregistrement à jet d'encre et appareil ayant la capacité de transformation de résolution
US6002804A (en) * 1998-03-26 1999-12-14 Hewlett-Packard Company Tone dependent variable halftoning with adjustable algorithm selection
US6257693B1 (en) 1994-01-27 2001-07-10 Hewlett-Packard Company Automatic optimization of hardcopy output
EP1331596A2 (fr) * 2001-12-25 2003-07-30 Seiko Epson Corporation Impression avec réduction de bavures aux contours

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0722835B1 (fr) * 1994-05-11 2000-03-22 Seiko Epson Corporation Procede d'impression par jet d'encre et imprimante
US5635967A (en) * 1994-08-15 1997-06-03 Xerox Corporation Image processing method to reduce marking material coverage in printing processes
JP5537087B2 (ja) * 2009-08-17 2014-07-02 理想科学工業株式会社 画像データ生成方法および装置並びに孔版印刷装置

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JPS61290060A (ja) * 1985-06-17 1986-12-20 Canon Inc カラー画像形成方法及びカラー画像処理方法

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US4415920A (en) * 1980-09-19 1983-11-15 Canon Kabushiki Kaisha Image signal processing unit
US4595948A (en) * 1982-10-13 1986-06-17 Ricoh Company, Ltd. Multicolor ink jet recording apparatus having means for preventing blurring of ink
JPS61290060A (ja) * 1985-06-17 1986-12-20 Canon Inc カラー画像形成方法及びカラー画像処理方法

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Cited By (32)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0536971A1 (fr) * 1991-10-07 1993-04-14 Hewlett-Packard Company Procédé pour atteindre approximativement la résolution complète d'une impression en couleurs
US5375191A (en) * 1991-10-07 1994-12-20 Hewlett-Packard Company Method for approximating full resolution color printing
AU675221B2 (en) * 1992-07-24 1997-01-30 Canon Kabushiki Kaisha Ink jet recording method employing ink of different characteristics and apparatus therefor
EP0585521A1 (fr) * 1992-09-03 1994-03-09 Hewlett-Packard Company Amélioration des bordures de couleur d'une imprimante électrostatique multicolore
US5512923A (en) * 1992-09-30 1996-04-30 Hewlett-Packard Company Color variation control method for ink-jet printers
EP0590848A1 (fr) * 1992-09-30 1994-04-06 Hewlett-Packard Company Méthode pour contrôler la variation de couleur pour des imprimantes à jet d'encre
EP0596373A3 (fr) * 1992-10-30 1995-01-11 Canon Kk Appareil et méthode de production d'une image noire dans laquelle l'encre noire recouvre l'encre de couleur.
EP0596373A2 (fr) * 1992-10-30 1994-05-11 Canon Kabushiki Kaisha Appareil et méthode de production d'une image noire dans laquelle l'encre noire recouvre l'encre de couleur
EP0947330A1 (fr) * 1992-10-30 1999-10-06 Canon Kabushiki Kaisha Dispositif de production d'une image noire dans laquelle l'encre noire recouvre l'encre de couleur
EP0947331A1 (fr) * 1992-10-30 1999-10-06 Canon Kabushiki Kaisha Méthode de production d'une image noire dans laquelle l'encre noire recouvre l'encre de couleur
US6186615B1 (en) 1992-10-30 2001-02-13 Canon Kabushiki Kaisha Apparatus and method for forming a black image in which black ink is overlaid on color ink
US5717448A (en) * 1993-07-30 1998-02-10 Canon Kabushiki Kaisha Ink jet printing apparatus and ink jet printing method
EP0636482A3 (fr) * 1993-07-30 1995-05-03 Canon Kk Dispositif et méthode d'impression à jet d'encre.
US5760798A (en) * 1993-09-24 1998-06-02 Canon Kabushiki Kaisha Ink jet recording apparatus and method in which an amount of ink ejected is corrected according to a recording head state
EP0645246A1 (fr) * 1993-09-24 1995-03-29 Canon Kabushiki Kaisha Appareil à jet d'encre et méthode d'enregistrement
EP0858898A1 (fr) * 1993-09-28 1998-08-19 Canon Kabushiki Kaisha Appareil d'enregistrement à jet d'encre et procédé pour pouvoir empêcher les barbouillages d'encre en amincissant les points d'encre
US5907332A (en) * 1993-09-28 1999-05-25 Canon Kabushiki Kaisha Ink jet recording apparatus and method capable of preventing ink blurring by thinning ink dots
EP0645247A1 (fr) * 1993-09-28 1995-03-29 Canon Kabushiki Kaisha Appareil d'enregistrement à jet d'encre et procédé pour pouvoir empêcher les barbouillages d'encre en amincissant les points d'encre
US5731823A (en) * 1994-01-27 1998-03-24 Hewlett-Packard Company Automatic optimization of hardcopy output for enhanced appearance and throughput
US6257693B1 (en) 1994-01-27 2001-07-10 Hewlett-Packard Company Automatic optimization of hardcopy output
EP0687565A3 (fr) * 1994-06-17 1998-09-16 Canon Kabushiki Kaisha Méthode d'enregistrement à jet d'encre et appareil ayant la capacité de transformation de résolution
EP1145858A3 (fr) * 1994-06-17 2001-12-05 Canon Kabushiki Kaisha Méthode d'enregistrement à jet d'encre et appareil ayant la capacité de transformation de résolution
EP1154372A3 (fr) * 1994-06-17 2002-08-28 Canon Kabushiki Kaisha Méthode d'enregistrement à jet d'encre et appareil ayant la capacité de transformation de résolution
US6024438A (en) * 1995-12-14 2000-02-15 Mitsushita Denki Kabushiki Kaisha Ink jet printer
EP0779159A3 (fr) * 1995-12-14 1998-06-10 Mitsubishi Denki Kabushiki Kaisha Imprimante à jet d'encre
CN1085150C (zh) * 1995-12-14 2002-05-22 三菱电机株式会社 喷墨记录装置
US6002804A (en) * 1998-03-26 1999-12-14 Hewlett-Packard Company Tone dependent variable halftoning with adjustable algorithm selection
US6661533B1 (en) * 1998-03-26 2003-12-09 Hewlett-Packard Development Company, L.P. Tone dependent variable halftoning with adjustable algorithm selection
US6801337B2 (en) 1998-03-26 2004-10-05 Hewlett-Packard Development Company, L.P. Tone dependent variable halftoning with adjustable algorithm selection
EP1331596A2 (fr) * 2001-12-25 2003-07-30 Seiko Epson Corporation Impression avec réduction de bavures aux contours
EP1331596A3 (fr) * 2001-12-25 2004-06-09 Seiko Epson Corporation Impression avec réduction de bavures aux contours
US7292356B2 (en) 2001-12-25 2007-11-06 Seiko Epson Corporation Printing with reduced outline bleeding

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EP0390473A3 (fr) 1991-04-10
DE69010367D1 (de) 1994-08-11
JP2752421B2 (ja) 1998-05-18
JPH02253958A (ja) 1990-10-12
DE69010367T2 (de) 1994-12-01
EP0390473B1 (fr) 1994-07-06

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