JPS6097856A - Digital printer - Google Patents

Abstract

PURPOSE:To reduce the displacement of a color and the displacement of an image by dividing recording information in one recording line of a main scanning direction in response to the displacement of the parallelism of a main scanning direction recording line between recording portions and differentiating the information. CONSTITUTION:Images of a lateral one line are not recorded at the simultaneous timing at the time of recording lines, divided into several lines in response to the displacement of the parallelism, the timing is, for example, displaced in recording to B0, B1, B2 lines to record the information. Then, the displacement of the recording can be reduced. When the allowable displacement is, for example, set to one pitch, the picture elements of one line are divided into 1/4-1/5, divided, for example, into 5 lines of every 500 surface elements and recorded. Then, the record can be performed within the range of the displacement of allowance. In this case, these corrections may be decided in the number of dividing lines by measuring the image pattern recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention provides a plurality of recording units that divide an image into a plurality of pixels and sequentially record each recording line in the main scanning direction. The present invention relates to a digital printer that records a composite image by passing recording paper through each recording section.

[Prior art]

Conventionally, as such an apparatus, there is a multicolor transfer type thermal recording apparatus equipped with a line type thermal head.

As shown in the perspective view of FIG. 1, this multicolor thermal recording apparatus has a plurality of recording units 10 and 20 each consisting of a back roller 1, a thermal head 2, and an ink donor film 3 in the feeding direction of the recording paper 4 (sub-scanning direction). direction) ink donor films 3 arranged in a column with respect to K and in each recording section 10.20.
The 0 colors are different, and the recording part 1 of the first row is
For example, by sequentially performing printing in the color yellow at 0, and printing in the color magenta in the next stage printing section 20, yellow is produced.

This is to realize multicolor recording on the recording paper 4 by combining magenta colors.

Incidentally, the image of each color in this case is separated into a plurality of pixels and sequentially recorded in the sub-scanning direction line by line in the main-scanning direction.

However, if the parallelism of each recording section in the main scanning direction (parallelism of recording lines) deviates due to installation error of the thermal head 2, the image of each pixel on each recording line of recording sections 10° and 20 As shown by symbols A and B in FIG. 2, the images are recorded with an inclination of a certain angle .theta., resulting in a color shift in the composite image and a deterioration in image quality.

Note that the circles in FIG. 2 represent unit pixels.

[Purpose of the invention]

The present invention was made in view of the above-mentioned drawbacks of the conventional art, and its purpose is to provide a digital printer that can reduce color shift or image shift caused by misalignment of parallelism in the main scanning direction in each recording section. be.

[Structure of the invention]

The present invention divides recording information in one recording line in the main scanning direction according to the deviation in parallelism of the recording lines in the main scanning direction between each recording part, and records the recording lines differently. be.

〔Example〕

3C is a diagram showing an example of the recording method according to the present invention, and when the parallelism of the recording lines of A and B is an angle θ as shown in FIG. This shows an example in which the image information of each recording line is not recorded simultaneously for each line, but is recorded separately into recording lines B11 + BI tBy according to the amount of deviation in parallelism.

By doing this, recording deviation can be reduced.

That is, if the parallelism of the recording line is the angle θ as shown in Figure 2, then ■ If the length of the recording line is l, then
The maximum value Δy of recording deviation is Δy−1−−〇 ・・・・・・
...(1).

Here, if the pitch of each pixel indicated by the circle in FIG.
When y is expressed as pitch, Δy-t--θ=D-Ptmθ
...-f2).

Therefore, for example, θ-0.1°, D=2500 torr,
! :, Δ3'-2500・-(0,1")・P-4,4
(PC pitch) ...... (3).

Therefore, when recording the B line, instead of recording the pictures of one horizontal line at the same time, they are divided into several lines according to the parallel work as shown in Figure 3 (for example, B., B1.B1).
If the timing is shifted to l-line recording), it is possible to reduce the recording deviation.

For example, when the permissible deviation is one pitch, recording can be performed within the permissible deviation by dividing each element into five lines.

In this case, these corrections may be made by measuring the recorded image pattern to determine the number of line divisions; however, as an example of application to a copying machine, for example, the image pattern may be used to measure the amount of recording deviation in advance. It is also possible to make a test recording, read the recorded pattern again, and automatically make corrections according to the amount of parallelism deviation (5).

Furthermore, even in devices such as wire dot printers and laser printers that are equipped with a recording section that serially scans one line, it is possible to correct all recording deviations due to deviations in scanner parallelism.

〔Effect of the invention〕

As is clear from the above description, according to the present invention, the recorded information in one recording line in the main scanning direction is divided according to the deviation in parallelism of the recording lines in the main scanning direction between each recording section, and Since recording is performed with different values, it is possible to reduce image recording deviations or color deviations, thereby improving the quality of one image.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing an example of a multicolor transfer type thermal recording device;
FIG. 2 is a diagram showing recording deviation, and FIG. 3 is a diagram showing a recording method according to the present invention. 1...Back roller, 2...Thermal head, 3.
...Ink donor film, 4...Recording paper, 10.2
0... Recording section. (7)

Claims (1)

[Claims] In a digital printer that includes multiple recording units that divide an image into multiple pixels and sequentially record each recording line in the main scanning direction, and that records a composite image by passing recording paper through each recording unit, each recording unit A digital printer characterized in that recording information in one recording line in the main scanning direction is divided according to a deviation in parallelism between recording lines in the main scanning direction, and recording is performed in different recording lines.