摘要:
There is provided a printing registration method for stably performing printing registration in bi-directional scanning by a print head in a printing apparatus or printing registration between a plurality of print heads with high accuracy. In complementary printing by the bi-directional scanning by the head, a plurality of patterns are printed while printing starting timings are shifted by predetermined quantities with respect to reference dots (dots formed by forward scanning). In the pattern, an area factor defined by the dots formed by the printing is varied according to the shifting. The plurality of patterns are optically read as an average density. The timing corresponding to a point where the read average density is highest can be determined as a printing registration condition. Furthermore, an optical sensor used for the reading is located at a position where an S/N ratio is stable with respect to fluctuations in distance from the object to be read, thus achieving stable reading.
摘要:
In complementarily printing by bi-directional scannings of a head or by a plurality of print heads, first patterns and second patterns including reference dots for example, dots formed by a forward scan of the bi-directional scannings or by one of the plurality of print heads and dots each having the different direction of shifting of relative printing positions to the reference dots are printed in corresponding to the plurality of shifting amounts. These first and second patterns have the similar characteristics of a change in density. The difference is only that their characteristics in density change are inverted according to the direction of shifting. The intersection point of these two characteristics in density change is obtained as a position for adjustment where dot-formed positions match. This makes it easy to perform printing registration in a printing apparatus in the case of printing by a forward and reverse scan of a printing head or in the case of printing by means of a plurality of printing heads. In this case, operations by a user etc. are also unnecessary and are easily performed.
摘要:
In a complimentary printing by bi-directional scanning of a head or by a plurality of heads, a plurality of patterns in which a print start timing is shifted by a predetermined amount are printed with respect to a reference dot, e.g. formed by the forward scan of the bi-directional scanning or by one of the plurality heads. In these patterns, an area factor by the dots formed by printing of the patterns is designed to be varied depending upon shifting amount. An average density is read from each of the plurality of patterns, optically. The timing at which the maximum one among average densities read from the patterns is obtained, can be set as the printing registration condition. Further, a processing including a coarse adjustment to a fine adjustment is performed in a series of algorithm. By these processings, printing registration between a forward and a reverse scan of a print head or printing registration between a plurality of print heads in a printing apparatus can be performed simply and with high accuracy, without operating by a user.
摘要:
A construction of a printing apparatus wherein a printing registration with respect to forward and reverse scans of a printing head and a printing registration with respect to a plurality of printing heads are automatically carried out is realized without rendering the apparatus complex or causing its production cost to rise. To this end, the optical sensor for measuring patterns formed for use in printing registration is also used to serve other purposes such as a detection of a printing home position or a detection of a printing medium's end. Furthermore, by appropriately controlling a single optical sensor according to each of various intended purposes, the optimum characteristics are utilized in each respective operating mode. Because of the above, the addition of sensors to be used only for the purpose of printing registration and the accompanying rise of the print apparatus production cost are restrained.
摘要:
In a complimentary printing by bi-directional scanning of a head or by a plurality of heads, a plurality of patterns in which a print start timing is shifted by a predetermined amount are printed with respect to a reference dot formed by the forward scan of the bi-directional scanning or by one of the plurality heads. In these patterns, an area factor by the dots formed by printing of the patterns is designed to be varied depending upon shifting amount. An average density is read from each of the plurality of patterns, optically. The timing at which the maximum one among average densities read from the patterns is obtained, can be set as the printing registration condition. Further, before the above reading operation, an optical sensor used for this operation is calibrated, for improving accuracies of the reading and the registrating. By these processings, printing registration between a forward and a reverse scan of a print head or printing registration between a plurality of print heads in a printing apparatus can be performed simply and with high accuracy.
摘要:
A first printing pattern is formed for a patch by means of a paper feed upstream side part of a black head. Then, a second printing pattern is formed for the patch by means of a cyan head in the following scans, and density of the patch is read by a reflection optical sensor in a scan after the completion of both patterns.
摘要:
A first printing pattern is formed for a patch by means of a paper feed upstream side part of a black head. Then, a second printing pattern is formed for the patch by means of a cyan head in the following scans, and density of the patch is read by a reflection optical sensor in a scan after the completion of both patterns.
摘要:
In the case where an image is formed with a mixture of large and small droplets by bi-directional printing in an ink jet printing apparatus in which ink is ejected in the form of, e.g., a droplet for printing operation while scanning by a print head, misalignment caused by a difference in ejection speed between the large and small droplets is prevented. For this purpose, there is provided a printing registration method according to the present invention comprises the steps of forming reference dots with the large and small droplets in forward scan printing, forming shifted dots in reverse scan printing on changed registration conditions, acquiring a adjustment value of the condition of dot forming positions on the basis of optical characteristics according to a plurality of shifting amounts of the relative printing positions between forward scanning and reverse scanning, controlling the order of formation of the large and small dots in the forward scanning and the reverse scanning, and correcting the adjustment value according to the offset amount of the small dot forming positions on the basis of the difference in ejection speed or the like.
摘要:
A plurality of patterns respectively having different area factor of dot formation area are formed by forward and reverse scanning printing of a print head, and then optical characteristics of the plurality of formed patterns are measured. A function representing the relationship between the printing position offset between the forward and reverse printings is determined from the optical characteristics. Then, respective pattern having a predetermined area factor of dot formation area is formed by means of forward and reverse scanning where the speed is differentiated according to the mode of a printing apparatus, and then the optical characteristics of this pattern is measured. By applying this measured optical characteristics to the function, an adjustment value of the dot formation position conditions between the forward and reverse scans is obtained for each mode. This makes it easy to perform printing registration in a printing apparatus in the case of printing by a forward and reverse scan of a printing head or in the case of printing by means of a plurality of printing heads. In this case, operations by a user etc. are also unnecessary and are easily performed.
摘要:
Images are printed with a reduced extent of a joint streak regardless of the type of a printing medium or the number of printing passes and a printing speed is increased without executing an unwanted thinning for correcting the joint streak. More specifically, printing method information added to print data is obtained, and it is determined on the basis of this information whether or not to execute a thinning process. Consequently, inter-band data correction process based on the thinning can be executed depending on the type of the print medium and the number of printing passes, thereby achieving an appropriate thinning depending on the type of the print medium or the like. When the thinning is not to be executed, all the processes related to the thinning can be omitted to prevent a decrease in printing speed.