Abstract: A vertical-cavity surface-emitting (VCSEL) device has a layer structure including a top DBR mirror, an active layer, a current confinement oxide layer, and a bottom DBR mirror, the layer structure being configured as a mesa post. The current confinement oxide layer has a central current injection area and a peripheral current blocking area oxidized from the sidewall of the mesa post. The mesa post has a substantially square cross-sectional shape, thereby allowing an oxidation heat treatment to configure a substantially circular current injection area in the current-confinement oxide layer.

Abstract: Mask patterns to be used for multi-pass printing make it possible to make a print with a higher quality at a higher speed. Specifically, by performing a swapping process with adjacency forbiddance, two points in the horizontal direction, or the scanning direction of a printing head, are selected in a buffer in which codes for each scan pass are set depending on printing ratios of a gradation mask. Subsequently, codes are swapped between the two points. By this swap, adjacencies between print permitting areas are eliminated in the mask pattern. As a result, when driving frequencies set for the printing head is kept constant, the scanning speed can be doubled at minimum.

Abstract: A pattern forming method that includes forming a pattern for detecting defective discharges of a plurality of ink discharging nozzles and recording a first dot pattern with the plurality of ink discharging nozzles. The pattern forming method also includes recording a second dot pattern to be adjacent to at least one side of the first dot pattern in the predetermined direction.

Abstract: A plurality of ejection portions are divided into groups, each containing at least one ejection portion, so that the suction-based recovery operation can be performed for each group independently. Since the number of ejection portions contained in each group differs, if an ink flow resistance varies among the different groups, simultaneous suction-based recovery operations can be done by using a common suction pump, without having to sequentially perform the suction-based recovery operations under an optimum pump driving condition. For this purpose, inner diameters of a plurality of ink discharge tubes running from a plurality of cap units, which cap a plurality of print head units having different numbers of ejection portions, to the common pump are differentiated. This allows different flows to be produced in different ink discharge systems, thus generating desirable ink flows for individual ink supply systems.

Abstract: An amount of deposit in an ink receiving portion can be controlled using an inexpensive configuration which does not require any complicated mechanisms or control and which avoids increasing ink consumption. An ejection control section controls ejecting of ink from a printing section into an ink receiving portion. The printing section has a first ink ejecting portion that ejects ink that accumulates easily in the ink receiving portion and a second ink ejecting portion that ejects ink that is hard to accumulate in the ink receiving portion. The ejection control section changes the landing position, in the ink receiving portion, of the ink ejected from the ink ejecting portions depending on the status of accumulation of the ink in the ink receiving portion.

Abstract: A plurality of ejection portions are divided into groups, each containing at least one ejection portion, so that the suction-based recovery operation can be performed for each group independently. Since the number of ejection portions contained in each group differs, if an ink flow resistance varies among the different groups, simultaneous suction-based recovery operations can be done by using a common suction pump, without having to sequentially perform the suction-based recovery operations under an optimum pump driving condition. For this purpose, inner diameters of a plurality of ink discharge tubes running from a plurality of cap units, which cap a plurality of print head units having different numbers of ejection portions, to the common pump are differentiated. This allows different flows to be produced in different ink discharge systems, thus generating desirable ink flows for individual ink supply systems.

Abstract: An ink jet printing apparatus and an ink jet printing method are provided in which information about an ink amount ejected on each of unit areas into which a preceding print medium is divided and information about a size of a following print medium are acquired. A delay time for delaying a printing operation for the following print medium is set based on the information about the ink amount ejected on unit areas which are decided among the divided unit areas according to the information about the size of the following print medium.

Abstract: A content (an amount of ink to be suctioned, or the number of times ink is preliminarily ejected) of the maintenance process to be performed after the ink tank replacement is made different depending on the amount of ink so far consumed from a tank which is replaced. This makes it possible to check the color mixture which would otherwise occur after the new ink tank is attached to the printing apparatus, and to concurrently manage an amount of waste ink in order that ink should not be consumed more than necessary in a case where the color mixture is less likely to occur.

Abstract: An ink jet recording apparatus is structured to perform discharges in the capping status when preliminary discharges are performed in a shot number larger than a predetermined number, and perform discharges in a cap or a preparatory port other than the cap when the preliminary discharges are performed in a shot number less than the predetermined number. With the structure thus arranged, it is made possible to implement the suppression of the mist generation due to the preliminary discharges, and to make the time of recording on a recording medium shorter as well.

Abstract: For a recording apparatus capable of supplying a plurality of different color inks to a plurality of recording element substrates, when a condition for performing maintenance on a first recording element substrate is met, it is determined whether or not to perform maintenance on a second recording element substrate according to how close the second recording element substrate is to meeting the condition. Since maintenance is performed on the first and second recording element substrates in such a manner, unnecessary maintenance operations will be prevented from being carried out multiple times within a short period of time. Accordingly, the total amount of time required for maintenance is reduced.

Abstract: In an image printing apparatus for printing an image by combining dots of a plurality of sizes, a banding problem attributable to variations in conveying operation, and a temperature rise of a print head with an increase of the number of ejections are solved with a relatively simple configuration. To this end, a combination of dots of a plurality of sizes is assigned to each of pixels expressed at a plurality level of density. In this assignment, a dot larger than a pitch of an image resolution is preferentially allocated to a pixel having a density level higher than that to which one dot smaller than the pitch of the image resolution is allocated.

Abstract: Provided are an ink jet printing apparatus and an ink jet printing method which are capable of printing high-quality images by performing printing scanning in a forward direction and in an opposite direction without needing complicated control of a transfer amount of a printing medium nor causing throughput degradation. Inks are ejected from odd-numbered nozzles in scanning in the forward direction and are ejected from even-numbered nozzles in scanning in the opposite direction.

Abstract: When completing an image in a predetermined area by an odd or even number of bidirectional printing scans, this invention makes it possible to suppress lines of image defects and density variations and thereby print a high-quality image at high speed. In completing an image by an odd number of bidirectional printing scans, the print data for small ink droplets and large ink droplets are thinned using the first and second thinning pattern. The first and second thinning pattern thin the print data for small ink droplets and large ink droplets so that a difference between the total print ratio of all forward printing scans of the odd number of scans and the total print ratio of all backward printing scans of the odd number of scans when the first thinning pattern is used differs from that when the second thinning pattern is used.

Abstract: An object of this invention is to prevent prolongation of the time taken for a suction recovery operation while suppressing wasteful consumption of ink in the suction recovery operation. An ink-jet printing apparatus includes a plurality of caps which, when a plurality of nozzles of an ink-jet head are divided into a plurality of nozzle groups, are arranged one by one for the respective nozzle groups, and cap the respective nozzle groups, a suction pump which generates a negative pressure in the plurality of caps to suck ink from the plurality of nozzles, and is arranged commonly for the plurality of caps, and a control unit which controls the suction pump so as to make the negative pressure by the suction pump act on all the caps when a common negative pressure is generated in the plurality of caps, and make different negative pressures by the suction pump act sequentially on the plurality of caps when different negative pressures are generated in the respective caps.

Abstract: An object of this invention is to prevent prolongation of the time taken for a suction recovery operation while suppressing wasteful consumption of ink in the suction recovery operation. An ink-jet printing apparatus includes a plurality of caps which, when a plurality of nozzles of an ink-jet head are divided into a plurality of nozzle groups, are arranged one by one for the respective nozzle groups, and cap the respective nozzle groups, a suction pump which generates a negative pressure in the plurality of caps to suck ink from the plurality of nozzles, and is arranged commonly for the plurality of caps, and a control unit which controls the suction pump so as to make the negative pressure by the suction pump act on all the caps when a common negative pressure is generated in the plurality of caps, and make different negative pressures by the suction pump act sequentially on the plurality of caps when different negative pressures are generated in the respective caps.

Abstract: When three primary color inks and a particular color ink having a hue different from those of the three colors are used, the number of passes with regard to the same printing area is changeable, thereby speeding up a printing operation and improving color development at a gamut expressed by the particular color ink to achieve high quality images. Use or non-use of the particular color ink is switched according to the number of passes corresponding to quality information. If a high speed data generation processing is not required but sufficient color development is achieved, namely if the number of passes is large, the use of the particular color will expand the color reproduction gamut. If the high speed is required, namely if the number of passes is small, non-use of the particular color ink will reduce the number of colors of the usable inks.

Abstract: A content of (an amount of ink to be suctioned for, or the number of times ink is preliminarily ejected for) the maintenance process to be performed after the ink tank replacement is made different depending on the amount of ink so far consumed from a tank which is replaced. This makes it possible to check the color mixture which would otherwise occur after the new ink tank is attached to the printing apparatus, and to concurrently manage an amount of waste ink in order that ink should not be consumed more than necessary in a case where the color mixture is less likely to occur.

Abstract: High image quality is maintained even on front and rear ends of a printing medium where deterioration in the image quality is more likely to occur due to reduction in conveyance accuracy of the printing medium. In printing on the front and rear ends, the printing medium being not supported by both conveying means respectively placed upstream and downstream of a printing point in a printing medium conveying direction, a print swath of a printing head and the amount of conveying a printing medium are reduced. Moreover, the reducing print swath and the reducing conveyance amount are designed to be decreased in the cases of selecting a printing medium for high-quality printing as well as a monochrome print mode where image distortion caused by deviation of ink-landing positions is more noticeable due to a small number of colors of ink to be used and low coverage thereof.

Abstract: The invention provides a configuration capable of judging whether an ink jet head is exchanged or whether it is replaced, and changing an amount of recovery operation when the ink jet head is exchanged or replaced. Thus a recording apparatus capable of avoiding a defective ink supply in case the ink jet head is exchanged or replaced, and not wasting the ink by unnecessarily excessive recovery operation, can be provided.

Abstract: The ink jet printing apparatus forms an image on a print medium with the following two operations. The printing operation makes a print head perform scan motions in a predetermined direction on the print medium, the print head having an array of nozzle rows corresponding to the required number of ink colors, each scan motion involving the ink being ejected from nozzles onto the print medium. The print medium feeding operation moves the print medium and the print head relative to each other a predetermined amount in a direction different from a direction of the scan motion between the scan motions. In a print mode using a small number of ink colors employed for printing, unidirectional printing is performed such that the nozzle row of a black ink to be ejected reaches a print start position when amplitude of vibration of the print head is a predetermined amount or less.