JPH04345866A - Printer and display thereof - Google Patents

Abstract

PURPOSE:To provide a printer for producing a print having no jaggy part and a display thereof. CONSTITUTION:The printer comprises a character generator 3 having a character font represented in gradation and a gradation control circuit 6 for controlling the conduction time, conduction current or conduction voltage of a print head 7 according to the ratio of image area in single dot thus making smooth the apparent profile of the image area even at an oblique part. Since the character font is represented in gradation, apparent profile of the image area can be made smooth even at a part where the profile traverses a pixel obliquely by varying the amount of light of a brightness signal to be outputted to a display according to the ratio of image area in single pixel through a gradation imparting means.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printing device and its screen display device.

0002

2. Description of the Related Art First, the configuration of a conventional printing device will be explained using a block diagram shown in FIG. CPU20 is ROM2
The printer controls the operations of each part of the printer and communicates with the host computer according to the program stored in the printer. CPU
20 is a character generator 22 that generates font data corresponding to the character code input from the host computer.
The dot string of the font data is then transferred to the head driver 24 according to print timing, and the head driver 24 drives the print head to perform printing.

Next, a screen display device of a conventional printing device will be explained using a block diagram shown in FIG. The CPU 25 develops the print code to be displayed on the V-RAM 26. V
- The data on the RAM 26 is sequentially read out according to the display timing and inputted to the character generator 27 as an address. The character generator 27 outputs the font data stored at the given address, and this font data is converted from parallel data to serial data by the shift register 28 and output to the display 29 as a binary luminance signal.

0004

[Problems to be Solved by the Invention] Conventional character fonts are based on binary dots, such as JISX9051-84 (16-dot character type for display devices) or JISX9052-83 (24-dot character type for dot printers). Represented as a collection. In JISX9051-84, the character of 50 points in ward 03 is "R". This conventional character font is expressed in binary values, so for example “
When the letter "R" is printed or displayed on a screen, as shown in Figure 10, there is no problem with vertical and horizontal lines, but when diagonal lines or arcs are displayed, the outline of the line becomes jagged, which is called jaggy. There's a problem.

[0005]

[Means for Solving the Problems] The invention according to claim 1 provides a gradation character generator that expresses a character font in gradation using a plurality of bits, and a gradation character generator that expresses a character font in gradation using a plurality of bits; The present invention is comprised of a temporary storage means for developing font data called from a character generator, and a gradation control circuit for driving a print head based on the font data transferred from the temporary storage means.

The invention according to claim 2 provides a gradation character generator that expresses a character font in gradations using a plurality of bits, and a multi-value luminance display on a display based on font data transferred from the gradation character generator. and a gradation imparting means for outputting a signal.

[0007]

[Operation] Since the character font is expressed in gradation, the invention according to claim 1 adjusts the energization time, current or voltage to the print head in accordance with the proportion of the image area of one dot (unit of printing pixel). By changing the tone using the gradation control circuit, it is possible to make the outline of the image area appear smooth even in portions where the outline of the image area crosses diagonally.

[0008] In the invention of claim 2, since the character font is expressed in gradation, the light amount of the luminance signal output to the display is adjusted to gradation according to the ratio of the image area of 1 pixel (unit of display pixel). By changing , it is possible to make the outline of the image area appear smooth even in a portion where the outline of the image area crosses diagonally.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the invention according to claim 1 will be described with reference to FIGS. 1 to 5. A CPU 1 that communicates with the host computer and controls various operations, a ROM 2 in which program data is written, a gradation character generator 3 that expresses character fonts in gradation using multiple bits, and input from the host computer. A RAM 4 is a temporary storage means for expanding font data called from the gradation character generator 3 corresponding to the character code to be displayed, and a control signal is output to the head driver 5 based on the font data transferred from the RAM 4. A gradation control circuit 6 is connected via a bus line. A print head 7 is connected to the head driver 5 .

FIG. 2 shows a set of dots. The hatched area is the printing area, and the blank area is the non-printing area. In the figure, 1 square is an area indicating 1 dot, and if the outline of the printing area is diagonal, line 8 is the ideal outline of the printing area, but if the character font is expressed in binary values, jaggies will occur. I understand that. Therefore, in the present invention, as shown in FIG. 3, the ratio of the image area is determined for each dot. For example, if the ratio of the image area is calculated in accordance with the image pattern in FIG. 2, the ratio of the image area in units of one dot will be 100% or less in the portion where the line 8, which is the outline of the image area, crosses diagonally.

[0011] Thus, the character font of the gradation character generator 3 is expressed in gradations according to the proportion of the image area. Here is a specific example. Figure 4 shows the characters “
The font for this part of the letter "R" is expressed in 4 levels of gradation for each dot according to the proportion of the image area, as shown in Figure 5. Therefore, the gradation level of a dot where the outline of the image area diagonally crosses with a straight line or curved line is less than 4.

[0012] In such a configuration, the CPU 1
According to the program stored in M2, the character font corresponding to the character code input from the host computer is called from the gradation character generator 3 and RA is executed.
The font data is developed on M4 and transferred to the gradation control circuit 6 in accordance with the timing of printing. The gradation control circuit 6 outputs control signals such as time, current, or voltage for driving the print head 7 to the head driver 5 according to the gradation of each dot. Therefore, differences in shading are applied to dots according to the degree of gradation, and for dots where the outline of the image area crosses diagonally, the proportion of the image area is expressed by the print density, and therefore the outline of the image area appears smooth. It can be done.

Next, a second embodiment of the invention according to claim 1 will be explained based on FIG. Components that are the same as those in the embodiment described above are designated by the same reference numerals, and description thereof will be omitted (the same applies hereinafter). In this example,
This uses a gradation character generator 3 that expresses a character font in gradation by dividing one dot divided by a solid line into a plurality of parts as shown by dotted lines.

In such a configuration, the distribution of dots diagonally across the image area is determined according to the proportion of the image area, so it is possible to express gradation even if expressed in binary terms, and therefore , it is possible to make the outline of the image area appear smooth even when the outline of the image area is a dot that crosses diagonally.

Next, an embodiment of the invention of claim 2 is shown in FIG.
The explanation will be based on. CPU 1, V-RAM 9, gradation character generator 3, and shift register 1
0, a D/A converter 11 serving as a gradation imparting means, and a display 12 are sequentially connected.

In such a configuration, the CPU 1 develops the print code to be displayed on the V-RAM 9. V-R
The data on AM9 is sequentially read out according to the display timing and inputted to the gradation character generator 3 as an address. The gradation character generator 3 outputs the font data stored at the given address, and this font data is converted from parallel data to serial data by the shift register 10. Here, the font data is data in which one pixel is represented by a plurality of bits, and this data is transmitted to the D/A converter 1.
1 is converted into an analog signal. This converted analog signal is output to the display 12 as a multivalued luminance signal.

Therefore, the brightness of the dots on the display 12 differs depending on the degree of gradation, and in pixels where the outline of the image area crosses diagonally, the proportion of the image area is expressed by the brightness, and therefore , the outline of the image area can be made smooth in appearance.

Although the explanation has been made with the font data corresponding to the image area of the pixel converted into a luminance signal by the D/A converter 11, the display 1
The same purpose can be achieved by expressing the brightness of each pixel by 2. That is, the means for determining the blink frequency according to the proportion of the image area of pixels may be used as the gradation adding means.

[0019]

[Effects of the Invention] The invention as claimed in claim 1 provides a gradation character generator that expresses a character font in gradation using a plurality of bits, and a gradation character generator that expresses a character font in gradation using a plurality of bits; The character font is expressed in gradation because it is composed of a temporary storage means for developing called font data and a gradation control circuit that drives the print head based on the font data transferred from the temporary storage means. Because, 1
By changing the energization time, current, or voltage to the print head according to the proportion of the image area of the dots, the appearance of the outline of the image area can be changed even in areas where the outline of the image area diagonally crosses pixels. It has the effect of being able to smooth the top.

The invention of claim 2 provides a gradation character generator that expresses a character font in gradations using a plurality of bits, and a multi-value luminance display on a display based on the font data transferred from the gradation character generator. Since the character font is expressed in gradations, the amount of light of the luminance signal output to the display is changed by the gradation adding means in accordance with the proportion of the image area of 1 pixel. By this,
This has the effect of making the outline of the image area appear smooth even in portions where the outline of the image area diagonally crosses pixels.

[Brief explanation of the drawing]

FIG. 1 shows a first embodiment of the invention of claim 1,
FIG. 2 is a block diagram of a printing device.

FIG. 2 is an explanatory diagram showing the image area.

FIG. 3 is an explanatory diagram showing the ratio of the image area.

FIG. 4 is an explanatory diagram showing a part of the specific image.

FIG. 5 is an explanatory diagram showing a part of the pattern of the specific character font.

FIG. 6 is an explanatory diagram showing a part of a specific character font pattern in a second embodiment of the invention of claim 1;

FIG. 7 is a block diagram of an image display device, showing an embodiment of the invention according to claim 2;

FIG. 8 is a block diagram of a conventional printing device.

FIG. 9 is a block diagram of a conventional image display device. It is.

FIG. 10 is an explanatory diagram showing conventional specific characters.

[Explanation of symbols]

1 CPU 3 Character generator with gradation 4
Temporary storage means 6 Gradation control circuit 7 Print head 11 Gradation imparting means 12 Display

Claims (2)

[Claims] Claim 1: A gradation character generator that expresses a character font in gradations using a plurality of bits, and font data called from the gradation character generator that is developed in response to a character code input from a host computer. What is claimed is: 1. A printing device comprising: temporary storage means for storing font data; and a gradation control circuit for driving a print head based on font data transferred from the temporary storage means. 2. A character generator with gradation that expresses a character font in gradation using a plurality of bits, and a gradation that outputs a multivalued luminance signal to a display based on font data transferred from the character generator with gradation. A screen display device for a printing device, comprising a toning means.