JPH03112671A - Printer - Google Patents

Abstract

PURPOSE:To obtain a printer difficult to generate collase of a character even though a small character is printed by a method wherein a pattern generation means which generates character patterns of plural size for one character code, and a control means which controls printing density in recording based on the generated character pattern size, are established. CONSTITUTION:A data to be outputted from a host computer 101 is stored successively in a page buffer 5 via an 1/F 4 and the stored data is simultaneously analyzed. A character pattern corresponding to a received character code is generated based on control codes of character size assignment or the like contained therein, which is expanded in a bit map memory 8. However, in the case where an assigned character size is small at that time, if printing is performed by the generated character pattern, said character will be collapsed. When such the collapse of the character is judged to occur, printing density is thinned in order to prevent said collapse. Then, an output image is obtained by being outputted from a printing part 9.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a printing device, and more particularly to a printing device that receives print data including character codes and prints a visible image on a recording medium.

[Prior Art] Conventionally, for example, in a printing section of a laser beam printer, an image is formed by turning on or off a laser diode or the like according to dot data "0" or "1". In order to produce a clear solid black print result, the spot diameter of the dots irradiated with laser light is made thicker so that they overlap with adjacent dots.

[Problems to be Solved by the Invention] However, when trying to print small or complex characters, the characters are often crushed due to the large dot diameter as mentioned above or process-related reasons such as toner scattering. There was a problem.

FIG. 7(A) shows a dot pattern of the character "a" used for printing, and FIG. 7(B) shows the printing result. Although FIG. 7(B) does not take into account toner scattering, it can be seen that the blank area surrounded by black dots is narrower than expected. On top of this, if you take into account the toner scattering, the characters become even more conspicuous and unreadable (it is easy to understand why).

The present invention has been made in view of this problem, and it is an object of the present invention to provide a printing device that does not cause blurring of characters even when printing small characters.

Another invention aims to provide a printing device that does not cause blurred characters even when printing complicated characters.

[Means for Solving the Problems J To achieve the above object, the recording apparatus of the present invention has the following configuration. That is, in a printing device that receives print data including a character code and prints a visible image on a recording medium, there is provided a pattern generating means that generates character patterns of a plurality of sizes for one character code, and a pattern generator that generates character patterns of a plurality of sizes for one character code, and A control means is provided for controlling print density during recording according to the size of the image.

Alternatively, in a printing device that receives print data including a character code and prints a visible image on a recording medium, a pattern generating means for generating a character pattern corresponding to the character code, and a character pattern generated by the pattern generating means are provided. A control means is provided for controlling print density based on complexity.

[Operation] In the configuration of the invention of Mizuei 1, the smaller the size of the generated character pattern, the lower the print density is controlled.

Furthermore, in the configuration of the second aspect of the invention, the printing density is controlled so that the more complex the generated character pattern is, the lighter the printing density becomes.

[Embodiments] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a block diagram of the printing apparatus of this embodiment.

In the figure, 100 is the main body of the printing apparatus of this embodiment, and 101
is a host computer that outputs print information.

The printing apparatus main body 100 includes the following configuration including a CPU that controls the entire apparatus.

Reference numeral 2 represents a ROM that stores and holds the operating processing procedures of the CPU (the program shown in the flowchart of FIG. 5) and a table shown in FIG. 3, which will be described later. Reference numeral 3 represents a RAM that is used as a work area while the CPU is operating. 4 is an interface (I/F) for receiving data from the host computer 101, and 5 is an interface (I/F) for receiving data from the host computer 101;
This is a page buffer that can store one page. 6 is a font memory that stores character patterns as data in coordinate format (in the example, it is an outline font)
It is. 7 is a pattern processing unit (details will be described later) that converts a character pattern generated based on the coordinate data stored in the font memory 6 into a gray pattern under the control of the CPUI; In case such a situation arises, a cache memory is also provided to save the effort of generating the character pattern. Reference numeral 8 denotes a bitmap memory in which an image such as a character pattern for one page can be developed. Reference numeral 9 denotes a printing unit that receives a video signal corresponding to the image data developed in the bitmap memory and records the image. It is assumed that the printing section 9 is a laser beam type printer.

In the above-described configuration, data output from the host computer 101 is sequentially stored in the page buffer 5 via the I/F 4, but at the same time, the stored data is analyzed and the character size specified therein is determined. A character pattern corresponding to the received character code is generated according to the control code such as , etc., and is developed in the bitmap memory 8.

However, at this time, it has already been explained that if the specified character size is small or complex, the characters will be crushed if the generated character pattern is printed. Therefore,
In this embodiment, when it is determined that such character collapse will occur, the printing density is reduced in order to prevent the collapse.

Therefore, the pattern processing section 7 of the embodiment has a configuration as shown in FIG.

In the figure, 11 is a work memory for developing generated character patterns, and 12 is a gray pattern memory that stores a plurality of gray patterns. 13 is work memory 1
14 is a font cache memory that stores the pattern obtained by the AND gate 13.

An outline of the operation of this pattern processing section will be explained using FIG. 4. Here, a case will be described in which a character pattern 41 (a character pattern generated from coordinate data stored in a font memory) is developed in the work memory 11 and a 50% gray pattern is specified.

Now, at this time, character pattern 41 and gray pattern 4
A pattern 43 is generated by logically multiplying 2 by the AND gate 13. This generated pattern 43 is stored in the font cache memory 14, and from now on, character patterns of the same character size and the same character code will not be newly generated (the patterns stored in the cache memory 14 will be used). In any case, the character pattern to be printed is expanded into the bitmap memory 8 and outputted from the printing section 9, thereby obtaining the output image 44.

To repeat the explanation, the above-mentioned process is performed when it is determined that the specified character size is small or complex, and the character pattern generated by faithful processing according to the data from the font memory 4 will be printed without being crushed. It is.

Therefore, the problem is how to determine whether or not the characters are crushed, but in the embodiment, the RO
The decision was made according to the table stored in M2.

FIG. 3 shows a part of this table.

As shown in the figure, data is stored for each character indicating the size (number of points) when printing and what percentage of the gray pattern to use when performing logical operations. For example, in the case shown, when printing the letter "a" at 5 points, a 50% gray pattern is used, and when printing the same letter at 10 points, a 70% gray pattern is used. has been shown to be used. In addition, the meaning of the percentage value is,
It shows the ratio of the number of dots that are 1° to the dot space. Incidentally, as a gray pattern, 10
0% indicates that pattern processing is unnecessary.

For example, the gray pattern 42 in FIG. 4 has dots ("Oo
o dot), the overall proportion of 1° is 50%. In other words, Figure 4 shows the character "a"
It can be seen that this is the process when printing "" in 5 points.

Based on the outline explained above, the operation processing of CPU1 is
The explanation will be given according to the flowchart shown in the figure.

Here, a case will be described in which data for one page has already been received in the page buffer 5.

First, in step S1, data (character code) is read from the page buffer 5, and in the next step S2, it is determined whether the character pattern corresponding to the read data is in the cache memory. If it exists in the cache memory, the process advances to step S8.

If there is no character code, the process proceeds to step S3, and a character pattern for the read character code is generated according to the character size designation code included in the received data. Then, in the next step S4, it is determined whether pattern processing is necessary or not by referring to the table. If it is determined that pattern processing is not necessary, the process proceeds to step S7, but if it is determined that pattern processing is necessary, the process proceeds to step S5.

In step S5, the percentage of gray pattern is detected by referring to the table based on the specified character size and character code, and in order to generate the gray pattern,
Access the gray pattern memory 12. As a result, in the next step S6, pattern processing is performed and a character pattern is generated.

Now, after step S6 or if the determination in step S4 is “
If NO, the process proceeds to step s7, where the generated or generated character pattern is registered in the cache memory.

In step S8, a character pattern corresponding to the read character code is read from the cache memory and expanded into the bitmap memory 8.

Next, in step S9, the processing from step 81 onward is repeated until it is determined that the development of character patterns for one page is completed.

When character patterns for one page have been developed in this manner, the image data developed in the bitmap memory 8 is sequentially read and output as a video signal to the printing unit 9, thereby forming an output image.

Through the above processing, it is possible to reduce the blurring of characters that occurs when printing small or complex characters.

Note that the present invention is not limited to the above-described configuration.

For example, the character pattern developed in the bitmap memory may be masked with a gray pattern at the stage of outputting to the printing section according to normal processing.

To achieve this, for example, a configuration as shown in FIG. 6 is adopted. Note that the diagram only shows the vicinity of the bitmap memory.

In the bitmap memory 21, a character pattern faithfully reproduced based on the coordinate data from the font memory is developed. Further, a gray pattern selected by the CPU is output to the gray pattern memory 23. Now, in this configuration, the video clock (VIDEOCLO) used to output data to the printing section
The parallel-to-serial converters 22 and 23 simultaneously read, for example, 8 bits each from the bit map memory 21 and the gray pattern memory 23 at a rate of once every eight pulses of CK). The read data is converted into a serial signal by shifting it bit by bit in synchronization with the video clock, and is output to the AND gate 25. Therefore, the AND gate 25 performs a logical AND operation between the normal character pattern developed in the bitmap memory and the gray pattern, and the result is outputted to the printing section as a video signal.

Through such processing, it becomes possible to obtain effects similar to those of the previously described embodiment.

In the embodiment, the printing unit is explained using a laser beam printer as an example, but the invention is not limited to this. In other words, this is because it can be adapted to a printer so that when small characters or complicated characters are printed, they will be blurred.

In the embodiment, the number of printed dots per unit area is reduced by ANDing the character pattern with the gray pattern.
This reduced the printing density.

However, it is not limited to this only. for example,
This is because, in the case of a laser beam printer, this can be achieved by changing the emission intensity of the laser beam. Also,
For example, in an inkjet printer or the like, the amount of ink ejected may be controlled.

Although the outline font is used as an example, it is also possible to use a different number of constituent dots (for example, 16X16.24X24.48X4).
The same applies to printers equipped with character fonts such as 8).

[Effects of the Invention] As explained above, according to the first invention, since the density of the characters when printed out is controlled according to the size of the characters, it is possible to suppress the blurring of small characters. Become.

Further, according to the second aspect of the present invention, since the printing density is controlled depending on the complexity of the characters, it is possible to suppress the blurring of the complicated characters.

[Brief explanation of drawings]

Fig. 1 is a block diagram of the printing device of the embodiment, Fig. 2 is a block diagram of the pattern processing section of Fig. 1, Fig. 3 is a diagram showing the contents of the table of the embodiment, and Fig. 4 is the embodiment. 5 is a flowchart showing the operation processing procedure of the CPU of the embodiment. FIG. 6 is a block diagram showing the configuration of the main parts in another embodiment. FIG. 2 is a diagram showing an outline of conventional printing. In the diagram, ■...CPU, 2...ROM, 3...RA
M. 4... I/F, 5... Page buffer, 6... Font memory, 7... Pattern processing section, 8... Bitmap memory, 9... Printing section, 11... Work Memory for use, 12... Gray pattern memory, 13...
AND gate, 14...cache memory.

Claims (2)

[Claims] (1) In a printing device that receives print data including a character code and prints a visible image on a recording medium, a pattern generation means that generates character patterns of multiple sizes for one character code, and a generated character A printing apparatus comprising a control means for controlling print density during recording according to the size of a pattern. (2) A printing device that receives print data including a character code and prints a visible image on a recording medium, comprising a pattern generating means for generating a character pattern corresponding to the character code, and a character pattern generated by the pattern generating means. 1. A printing apparatus comprising: a control means for controlling print density based on the complexity of the printing apparatus.