JPH09123508A - Recording method for serial printer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the superposed parts between recording lines to become dense by so recording the same record data as to superpose at least one dot line of adjacent recording lines, and thinning the record data of the superposed part with the previous line and recording at the time of recording next line. SOLUTION: In the case of recording an image, first a record of one line is executed on a recording sheet according to gradation data obtained based on record data by a serial printer. In the case of recording next line, in order to eliminate a gap between the lines, the sheet is so conveyed as to superpose at one dot at the final dot line of the previous line, and recorded. In this case, the record data of the superposed dot line is recorded by the same record data as that of the previous data, and suitable record data of the record data are thinned, and recorded. According to this, the superposed dot line does not become dense, but excellent recording state can be obtained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a recording method of a serial printer, and more particularly, to a desired gradation recording by making a dot growth order in a dot matrix adjacent to a dot already arranged in the dot matrix. The present invention relates to a recording method of a serial printer suitable for performing.

[0002]

2. Description of the Related Art Generally, a thermal printer, an ink jet printer, a bubble jet printer or the like which records an image such as characters and figures output from a word processor or a computer on plain paper, OHP paper, thick paper and the like. 2. Description of the Related Art A recording device called a dot printer is frequently used for reasons such as high recording quality, low noise, low cost, and ease of maintenance.

A thermal printer will be described as an example of such a conventional recording apparatus.

In a conventional thermal printer, a recording paper and an ink ribbon formed by applying a desired ink to a base film are supported in front of a platen, and a thermal head having a plurality of heating elements arranged as a recording head. While moving the head along with the carriage along the platen, the ink ribbon is fed out, and the heating elements arranged in the thermal head are selectively energized based on the recorded information to generate heat to partially melt the ink on the ink ribbon. Then, by transferring to a desired recording position on the recording paper, an image such as a desired character is recorded on the recording paper.

As a recording method for performing gradation recording, that is, recording a grayscale image in a conventional recording device, recording data is formed by a dither method in which one pixel is formed by a dot matrix composed of a plurality of dots. It was recorded. In this conventional method of forming print data called the dither method, the growth order of each dot in the dot matrix is randomly generated.

For example, as shown in FIG. 5, when one pixel is represented by a dot matrix M of 6 dots vertically and horizontally (36 dots in total), a dot pattern table (not shown) is used to change the number from 1 in FIG. The dot growth order is as indicated by reference numeral 36.

In the conventional serial printer, the heating elements of the thermal head are arranged in the vertical direction of the dot matrix M, and the thermal head is as shown in FIG.
The recording is performed for each column of the dot matrix M while moving in the recording direction indicated by arrow A in FIG.

However, in the recording method of the above-mentioned conventional serial printer, the growth order of the dots in the dot matrix M is random, and when a thermal printer is used as the recording device, each heat generation of the thermal head occurs. The energization order of the elements becomes random, and for example, for the dot matrix M shown in FIG.
In the case of gradation recording using 5 dots indicated by reference numeral 5 to 5, when the thermal head is located in the leftmost column (first column) in FIG.
The heating element corresponding to the position is energized, and the thermal head moves to the right column (second column) of the first column in FIG.
When it is located at, the heating elements corresponding to the positions of the symbols 1 and 4 of the dot matrix M are energized.
Next, when the thermal heads are located in the third row and the fourth row, the heating elements are not energized. After that, when the thermal head is located in the leftmost column (fifth column) of the rightmost column in FIG. 5, the heating elements corresponding to the positions 2 and 3 of the dot matrix M are energized. The energization of the dot matrix M ends.

Therefore, in the conventional serial printer recording method, since the five dots are randomly arranged in the dot matrix M, the intervals of the dots to be recorded are separated and the recording resolution is improved. In a heating element with a small area and a small heat capacity, the ink does not adhere well to the recording paper, and even if it is intended to record 5 dots, only 3 or 4 dots may actually be printed, and exactly 1 pixel is recorded. There is a problem in that it is difficult to express the density of.

Further, since the heating elements of the thermal head are energized at random, the heat history of each heating element becomes random, and the thermal control of the thermal head is performed by the energization correction such as history correction and area correction for each heating element of the thermal head. There was a problem that became complicated.

Further, in the case of an ink jet printer using liquid ink as a recording device, there is a problem that it is difficult to accurately express the density of one pixel due to bleeding of dots.

In order to improve such a conventional problem, the applicant of the present invention forms a dot growth order for the dot matrix M so that it is always adjacent to the arranged dots in the dot matrix M. A recording method of a serial printer is proposed in which recording data is formed and recorded by a so-called line method.

According to the printing method of this serial printer, the growth order of dots in the dot matrix M is formed so as to be always adjacent to the arranged dots in the dot matrix M, so that the pixels can be accurately recorded. It became possible to express the concentration.

On the other hand, in the conventional serial printer recording method, in order to prevent a gap from being generated between recording lines, when recording the next line after recording the preceding line, the recording line of the preceding line is recorded. The drive control of the transport roller (not shown) is performed so as to transport the recording paper by an amount corresponding to

However, in such a conventional serial printer recording method, if an error occurs in the amount of recording paper conveyed, a gap is created between recording lines to form white streaks, which leads to deterioration in recording quality. Had a problem.

With respect to such problems, the present applicant has
In the printing method of the serial printer using the parallel line method, when printing the next line after printing one line, the previous line and the next line are conveyed so as to overlap by a predetermined dot line, and the overlapping part The recording method of the serial printer is proposed so that the recording is performed based on the same recording data.

The recording method of this serial printer will be described with reference to FIGS. 6 and 7. 6 and 7
3A and 3B are diagrams showing a recording state when recording is performed by the recording method of this serial printer, and are formed in a striped pattern for convenience.

The recording method of this serial printer is a recording method in which the last dot line of the preceding line is always recorded based on the same recording data as the first dot line of the next line so that the recording lines overlap in one dot line. Is. According to such a recording method, even if the transport amount of the recording paper by the transport roller is reduced due to the transport error, the transport amount is secured from the beginning so as to overlap by one dot line, and thus a gap is generated between the recording lines. Can be suppressed.

[0019]

However, in the recording method of the conventional serial printer shown in FIG. 6 described above, it is possible to prevent the occurrence of a gap between the recording lines, but the gap between the preceding line and the next line is prevented. In the 1-dot line overlapped on the recording line, the color of the ink appeared dark. This is not a problem because it is not very noticeable when the resolution is not so demanded, but it has not been a satisfactory recording state even when the high resolution is required due to the recent technological innovation.

Further, FIG. 7 shows that when recording the next line,
It shows a recording state when the recording paper is conveyed by a conveyance error by more than a predetermined conveyance amount. In this case, not only the ink color appears dark in the recording line in which the preceding line and the next line are overlapped, but also the interval between the recording dot lines indicated by X in FIG. I was sick.

The present invention has been made in view of the above problems, and it is possible to prevent a gap from being formed between recording lines and to prevent an overlapping portion between recording lines from becoming dark. It is an object of the present invention to provide a recording method of a serial printer capable of recording.

[0022]

To achieve the above object, a serial printer according to a first aspect of the present invention is characterized in that at least one dot line of adjacent recording lines is overlapped. In addition to recording with the recording data of (1), the recording data of a predetermined position in the portion overlapping the preceding row is thinned and recorded when recording the next row. Further, by adopting such a configuration, it is possible to prevent a gap from being formed between the recording lines and to prevent the overlapping portion between the recording lines from becoming dark.

Further, a feature of the recording method of the serial printer according to the present invention is that the dot growth order for the dot matrix is formed so as to be adjacent to the dots already arranged in the dot matrix. . By adopting such a configuration, it is possible to accurately express the density of the pixel and perform better recording.

[0024]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of a recording method for a serial printer according to the present invention will be described below with reference to FIGS.

First, a method of forming print data among the printing methods of the serial printer according to the embodiment of the present invention will be described.

As shown in FIG. 1, in the recording data forming method in this embodiment, for example, when one pixel is expressed by a dot matrix M of 6 dots in each of vertical and horizontal directions (total of 36 dots), a dot matrix corresponding to the recording density is obtained. The growth order of each dot of M is formed by a so-called parallel line method in which dots arranged in each column of the dot matrix M are sequentially adjacent to each other in the lateral direction parallel to the recording direction indicated by arrow A in the figure. Has been done.

That is, as shown in FIG. 1, the dot matrix M has XY coordinates based on the X axis which is the recording direction and the Y axis which is the direction orthogonal to the recording direction, and the upper left corner is the origin (X0, Y0) of the XY coordinates. ), The first dot used for the lightest gradation shown by reference numeral 1 in the dot matrix M is generated at the coordinates (X0, Y3). Then, the next dot indicated by reference numeral 2 is generated at the coordinates (X1, Y3) of the position adjacent in the X-axis direction (horizontal direction) to the arranged dot first generated in the dot matrix M. . Below, coordinates (X2, Y3), coordinates (X3, Y3),
Dots are generated in the order of the coordinates (X4, Y3) and the coordinates (X5, Y3).

Next, the coordinate (Y3) in the Y direction (vertical direction)
When dots are generated at all positions in the X direction (horizontal direction) located at, the dots are generated at coordinates (X0, Y2) located at the next position in the Y direction (vertical direction). X0, Y2) are arranged so that they are sequentially adjacent to the dots arranged in the X-axis direction (horizontal direction), and the coordinates (X1, Y2).
2), coordinates (X2, Y2), coordinates (X3, Y2), coordinates (X4, Y2), and coordinates (X5, Y2) are generated in this order.

The coordinates (X0, Y1) and the coordinates (X1,
Y1), coordinates (X2, Y1), coordinates (X3, Y1), coordinates (X4, Y1), coordinates (X5, Y1), coordinates (X0,
Y0), coordinates (X1, Y0), coordinates (X2, Y0), coordinates (X3, Y0), coordinates (X4, Y0), coordinates (X5,
Y0), coordinates (X0, Y4), coordinates (X1, Y4), coordinates (X2, Y4), coordinates (X3, Y4), coordinates (X4,
Y4), coordinates (X5, Y4), coordinates (X0, Y5), coordinates (X1, Y5), coordinates (X2, Y5), coordinates (X3,
Dots are formed in the order of (Y5), coordinates (X4, Y5), coordinates (X5, Y5).

When gradation recording is performed using a thermal printer (not shown) as a recording device on the basis of the recording data thus formed, each heating element of the thermal head (not shown) performs recording. The dot matrix M, which is the direction, is continuously energized or de-energized. That is, when the heating elements corresponding to the positions corresponding to the plurality of dots in the dot matrix M are energized, the heating elements (not shown) located in the column direction, which is the vertical direction of the dot matrix M, are Since electricity is always applied continuously in the row direction (recording direction), the distance between recorded dots is minimized, and even in a heating element (not shown) with a small area and a small heat capacity to improve recording resolution. In addition, it is possible to reliably improve the ink adhesion to the recording paper (not shown), and it is possible to accurately and surely express the pixel density.

Further, since each heating element (not shown) of the thermal head is continuously energized or de-energized in the recording direction, when conducting energization correction such as history correction and area correction for each heating element of the thermal head. The heat control of can be simplified.

Next, the recording method of the serial printer based on the gradation recording data formed by the above-mentioned recording data forming method will be described.

In the recording method of the serial printer according to the present embodiment, as shown in FIG. 2, the last dot line of the preceding line and the first dot line of the following line are overlapped and recorded by one dot line. The first dot line in the next line is recorded by thinning out the recording data at a predetermined position.

More specifically, first, one line of recording is performed on the recording paper based on the gradation data obtained by the above-described recording data forming method by a serial printer (not shown). Then, when recording the next row, the recording paper is conveyed so as to overlap the last dot line of the preceding row by one dot in order to prevent a gap between the rows, and the recording of the next row is performed. The recording data in the overlapped dot lines is recorded by the same recording data as in the preceding row, and some suitable recording data of this recording data is thinned out and recorded. Which print data is to be thinned out may be arbitrarily determined, and for example, it may be alternately thinned out every dot in the recording direction.

When recording is performed by thinning out predetermined positions in this manner, the overlapped dots are compared to the case where all 1 dot lines between recording lines are overlapped and recorded as in the conventional recording method. The line is not darkened and a good recording state is exhibited.

Next, in the embodiment of the present invention, there is an error in the conveyance of the recording paper by the conveyance rollers, and the recording state in the case where the recording of the preceding line and the recording of the next line overlap by one dot line or more is shown in FIG. And FIG. 4 will be described.

As shown in FIG. 3C, in this case, the front end portion of the first dot line of the next row is projected and recorded above the last dot line of the previous row. The space between the recording dots indicated by X is closed. However, in reality, as shown in FIG. 3D, of the dot lines recorded by performing the thinning process on the next line, the portion protruding beyond the last dot line of the previous line is not printed on the recording paper. A normal interval can be maintained between the recording dots indicated by X without being transferred. Then, the distance indicated by Z is narrowed due to a transport error, but the recorded portion indicated by Y is also narrowed. Further, this recorded portion is superposed on the ink of the preceding line, and thus a little darker, The distance indicated by Z as a whole does not seem to be blocked.

Here, the reason why the portion of the dot lines recorded by performing the thinning process and protruding beyond the last dot line of the preceding row is not transferred will be described with reference to FIG.

FIG. 4 is a cross-sectional view taken along the line D--D in FIG. 3, and the portion indicated by A in the drawing is the portion of the recording portion of the next row which has been subjected to the thinning process. . Normally, the recording portion A should have completely overlapped with the last dot line of the preceding row indicated by B, but the recording portion indicated by C is projected and recorded due to a transport error. This recording section C
Originally, it is transferred on the ink of the preceding line as a base, but since it was recorded outside the ink of the preceding line that is the base, it is difficult to transfer, and actually it is hardly recorded on the recording paper. . Therefore, as shown in FIG. 2 described above, it is extremely rare to observe that the recording state is defective.

Therefore, according to the recording method of the serial printer in the embodiment of the present invention, not only can gaps be prevented from being generated between the recording lines, but also recording data can be thinned out at the portions where the recording lines overlap to perform recording. Therefore, it is possible to prevent the ink color from appearing dark due to the overlap between the recording lines.

Further, when the portion recorded by thinning the recording data due to the conveyance error exceeds the last dot line of the preceding line, the portion that has exceeded the last dot line is not transferred to the recording paper, and thus a recording error occurs. Is almost unnoticeable.

As a result, a very good recording state can be obtained.

The present invention is not limited to the above-mentioned embodiment, but can be variously modified as necessary.

[0044]

As described above, the recording method of the serial printer according to the present invention can not only prevent the formation of gaps between the recording lines, but also prevent the ink color from appearing dark due to the overlap between the recording lines. Can be prevented. In addition, the effect of the transport error can be minimized and a good recording state can be obtained.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram showing a recording data forming method in an embodiment of a recording method of a serial printer according to the present invention.

FIG. 2 is a diagram showing (a) a rear portion of the preceding row in the embodiment of the recording method of the serial printer according to the present invention;
(B) The figure which shows the front part of the next line, (c) The figure which shows the record state

FIG. 3 is an explanatory diagram showing a recording state when a conveyance error occurs in FIG.

FIG. 4 is a cross-sectional view taken along the line DD of FIG.

FIG. 5 is an explanatory diagram showing a method of forming print data in a printing method of a conventional serial printer.

FIG. 6A is a diagram showing a rear part of a preceding line, FIG. 6B is a diagram showing a front part of a next line, and FIG. 6C is a diagram showing a recording state in a conventional serial printer recording method.

FIG. 7 is an explanatory diagram showing a recording state when a conveyance error occurs in FIG.

[Explanation of symbols]

M dot matrix A recording part subjected to thinning processing B last dot line of the previous line C first dot line of the next line that exceeds the last dot line of the previous line due to transport error

Claims (2)

[Claims] 1. A recording method of a serial printer, in which one pixel is composed of a dot matrix formed by arranging a plurality of dots, and gradation recording is performed for pixels of a recorded image, and at least one dot line of adjacent recording rows. The serial printer is characterized in that the same recording data is recorded so as to overlap each other, and when recording the next line, the recording data at a predetermined position in the portion overlapping the preceding line is thinned out and recorded. Recording method. 2. The serial according to claim 1, wherein the dot growth order with respect to the dot matrix is formed so as to be adjacent to dots already arranged in the dot matrix, and gradation recording is performed. Printer recording method.