JPS61206674A - Multicolor thermal transfer printer - Google Patents

Abstract

PURPOSE:To enable printed densities of primary colors used to be independently varied and enable delicate tones to be reproduce, by providing a printed density varying means for independently varying the printed density of each color of an ink ribbon. CONSTITUTION:The printed density varying means is constituted of a density- reculating control 10 and a printed density controlling part 50. The control 10 includes controls 101, 102 and 103 for regulating the printed densities of colors Y, M and C, respectively. A controlling part 30 controls printing on the basis of a converted output from an A/D converter 20 and printing data (a) sent through a communication interface part 60. The part 50 varies a voltage impressed on a thermal head on the basis of a signal from the controlling part 30, thereby controlling the printed density. Accordingly, where the minimum and the maximum designated by the position of the control 10 are respectively 0 and 1, the printed densities of overlapping colors are varied according to the combination of the positions of the controls 101, 102, 103, whereby an arbitrary printing color can be formed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to improving the color reproducibility of a multicolor thermal transfer printer that performs thermal transfer recording using a plurality of colors.

[Conventional technology]

Some multicolor thermal transfer printers perform thermal transfer recording in multiple colors by using ink ribbons dyed in multiple colors, using each color as a primary color, and performing overcoating υ as necessary.

This multicolor thermal transfer printer can copy displayed images by connecting directly or indirectly to a display device.

Conventionally, such multicolor thermal transfer printers include, for example, Y
KLLOW, MAGENTA, CYAN (Rishita,
Using ink ribbons dyed into Y, M, and C), each color (these are the primary colors) is printed at a constant density, and these colors are overpainted as necessary. Due to this, there were some who reproduced the displayed image.

[Problem that the invention seeks to solve]

However, in such a multicolor thermal transfer printer, since the printing density of each primary color is constant, there is a problem in that even the delicate color tone 1 on the display screen cannot be reproduced. This is particularly a problem when reproducing a display screen that uses many intermediate colors.

The present invention has been made in order to eliminate the above-mentioned problems, and an object of the present invention is to realize a multicolor thermal transfer printer in which the print density of each primary color used can be independently varied and can reproduce even delicate tones.

[Means for solving problems]

The present invention provides a multicolor thermal transfer printer that uses ink ribbons dyed in multiple colors, uses each color as a primary color, and performs overcoating as necessary to perform thermal transfer recording in multiple colors. This is a multicolor thermal transfer printer characterized by having a print density changing means for independently changing the print density.

〔Example〕

The present invention will be explained below with reference to the drawings.

FIG. 1 is a block diagram of an embodiment of the present invention.

In Figure 1, 10 is the density adjustment volume, 20 digits A
/D converter, 30 is a control section, 40 is a printing section, 50 is a print density control section, 60 is a communication interface section (hereinafter referred to as 1/D converter)
F).

In this figure, the density adjustment volume 10 and the print density control unit 5
0 constitutes a print density changing means.

The density adjustment volumes 10 are provided with volumes 101, 102, and 103 for adjusting printing colors of Y, M, and C, respectively.

The A/D converter 20 has density adjustment buttons IJ and -101-1.
03 position is converted into digital data, for example, 8-bit data.

The control unit 30 is provided with a CPU, a memory, a ribbon sensor peripheral circuit, a head drive circuit, and the like. Control unit 30
controls printing based on the conversion output from the A/D converter 20 and print data sent via the I/F 60.

The printing unit 40 is provided with a printing mechanism, a paper feeding mechanism, and the like. Furthermore, the printing mechanism is provided with a thermal head, an ink ribbon, and a carriage feeding means. This printing section 40 performs printing based on signals from the control section 30.

The print density control section 50 also modulates the signal from the control section 30 and controls the print density by changing the voltage applied to the thermal head.

Next, the operation of such a multicolor thermal transfer printer will be explained.

The external host computer changes the color of the displayed image to Y or M.
, C, and one line of the screen as a unit.
Data for each color is transferred to the printer in sequence.

FIG. 2 shows an example of a transfer format for one line of data.

In Figure 2, AI, A2 and A3 are Y, M and C color specification commands, Bl, B2 and B3 are Y, M and C dot row print commands, and CI, C2 and C3 are Y, M
and C print data.

The data shown in FIG. 2 is received by the I/F 60 and stored in the memory within the control unit 30. The control section 30 decodes this data and sends a signal to the printing section 40 to print. This printing operation will be explained.

FIG. 3 is a flowchart showing the procedure for printing based on the data shown in FIG. Such processing is
It is executed by the CPH according to a program stored in the memory within the control unit 30.

In FIG. 3, the control unit 30 performs the cue of the ink ribbon, that is, selects the print color, based on the color designation commands A1 to A3 in the transfer data shown in FIG.

FIG. 4 shows the structure of the ink ribbon.

As shown in Fig. 4, the ink ribbon is
It is dyed into M, C and B (BLACK) color bands. A black marker is provided at the beginning of each color band. The cue of each color is detected by detecting the marker with a sensor, for example, a photointerrupter.

Further, the print density is adjusted as follows.

In the printer according to the present invention, print density is adjusted by applying voltage to the thermal head.

FIG. 5 is a block diagram of the main parts of the printer shown in FIG. 1.

Components in FIG. 5 that are the same as those in FIG. 1 are given the same reference numerals.

In FIG. 5, 31 is an input board, 32 is an arithmetic unit, and 3
3 is an output port, 51 is a D/A converter, 52 is a voltage regulator, 41 is a thermal head, and 42 is a switching circuit.

The position of the density adjustment volume 10 is converted into digital data by an A/D converter 31 and input to the calculation section 32 via the input port 31. The calculation unit 32 converts the input data into print density data while referring to the voltage applied to the thermal head and the print density characteristics, and outputs the data via the output port 33 . The D/A converter 51 is connected to the output port 3
The print density data passed through step 3 is first converted into voltage, but since current to drive the thermal head cannot be obtained in the current state, the voltage adjustment unit 52 converts it into a sufficient driving current. The lightning pressure adjustment section 52 operates as a variable voltage source based on the converted value of the D/A converter 51.

The switching circuit 42 turns on the thermal head using dot data (corresponding to data B1 to B3 in FIG. 2).
-Turn off.

Set the minimum and maximum values of the density adjustment volume 10 to 0.
and 1, the print density of the superimposed colors changes depending on the combination of the positions of each volume, creating a custom print color.

Here, depending on the printing order and the characteristics of the ink, the relationship between the voltage applied to the thermal head and the printing density is not necessarily linear in reality. The calculation unit 32 has a function of compensating for such nonlinearity.

That is, the relationship between the voltage applied to the thermal head and the print density, which was actually determined, is as shown in FIG. In Figure 6,
Y, M and C are characteristic curves for yellow, magenta and cyan.

A broken line approximation is performed based on the graph of FIG. 6, and the graph shown in FIG. 7 is created. In Figure 7, Y, M.

Regarding C, it is the same as in FIG. The graph shown in FIG. 7 is stored in the memory of the control unit 30, and when printing, the control unit 30 stores the graph shown in FIG. Refer to this to find the voltage to be applied to the thermal head.

As shown in the flowchart of FIG. 3, dot rows are sequentially printed in parallel with the above-described adjustment of print density.

Note that the multicolor thermal transfer printer may be a serial printer or a line printer.

In addition, in the example, the case where the density adjustment is performed manually (by changing the position of the density adjustment volume) has been explained, but the density adjustment is not limited to this, and the density adjustment can be performed automatically, for example, by adding a density setting command to the data transferred from the host converter. This may be adjusted depending on the contents of this command.

〔effect〕

According to such a multicolor thermal transfer printer, the following effects can be obtained.

That is, since the print density changing means is provided, the print density of each color of the ink ribbon used can be changed independently. This makes it possible to create printed colors with even subtle tones and faithfully reproduce the display screen. This is particularly effective when reproducing a display image with many intermediate colors.

Further, due to the above-mentioned features, it is possible to correct color fluctuations υ due to manufacturing variations in ink ribbons.

[Brief explanation of drawings]

FIG. 1 is a block diagram of the configuration of an embodiment of the present invention, and FIG.
4, 6, and 7 are explanatory diagrams of the operation of the link shown in FIG. 1, and FIG. 5 is a diagram showing the main parts of the printer shown in FIG. 1. 10, 101-103...Density adjustment volume, 20
... A/D converter, 30... Control section, 40... Printing section, 50... Print density control section, 60... Communication interface section.

Claims (2)

[Claims] (1) In a multicolor thermal transfer printer that uses ink ribbons dyed in multiple colors, each color is used as a primary color and overcoated as necessary to perform thermal transfer recording in multiple colors, the print density of each color of the ink ribbon is adjusted. A multicolor thermal transfer printer characterized by having a printing density changing means that changes independently. (2) The printing density changing means changes the voltage applied to the thermal head with reference to a graph showing the relationship between the voltage applied to the thermal head and the printing density. multicolor thermal transfer printer.