JPH05330138A - Printer controller - Google Patents

Abstract

PURPOSE:To print a composite pattern, in which a photographic image is added to a character and a graphic, at a high grade. CONSTITUTION:A printing data correction means corrects a printing data signal 32, and outputs the corrected data signal 32 as a corrected data signal 51 while outputting said printing data signal 32 as an original data signal 53 without correction. The corrected data signal 51 is used when smoothing is conducted and the original data signal 53 when smoothing is not conducted. Whether printing data are kept in a region, in which a character and a graphic and the like are smoothed, or in a region, in which a photographic image, etc., are not smoothed, is decided, and the corrected data signal 51 is selected by a selector circuit 52 when the character and the graphic and the like are smoothed and the original data signal 53 when the photographic image, etc., are not smoothed, and transferred to a printing head 35 as an actual printing data signal 34. The printing head 35 forms an electrostatic latent image on a photosensitive drum by the actual printing data signal 34.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a print control device for a non-impact printer.

[0002]

2. Description of the Related Art Conventionally, in a non-impact printer such as an electrophotographic printer, an electrostatic latent image is formed by irradiating the surface of a charged photosensitive drum with a light source.
Toner is attached to the electrostatic latent image and development is performed to form a toner image, and the toner image is transferred to a sheet and fixed.

In this case, a low resolution (for example, 300DP
With the resolution of I), since a jagged feeling remains in the shaded area, the laser-type non-impact printer is equipped with a buffer of about 7 lines, and the peripheral dots including the dot of interest are matched with the stored pattern, and the laser By changing the driving time, the shape of the dot of interest is changed to smooth the diagonal lines (Japanese Patent Laid-Open No. 2-112).
966).

Further, the LED type non-impact printer is provided with a buffer of about 9 lines, and the peripheral dots including the dot of interest are matched with the stored pattern to increase the vertical resolution four times. , 30
The dots are printed on a grid of 0 DPI (horizontal) × 1200 DPI (vertical), the irradiation time of the LED is increased or decreased, and the shape of the dot of interest is changed to smooth the diagonal lines.

FIG. 2 is a control block diagram of a conventional print control apparatus. In the figure, 10 is an interface, 11 is a microprocessor, ROM, RAM, input / output port,
A higher-order control unit configured by a timer and the like, 12 is an engine control unit configured by a microprocessor, ROM, RAM, input / output port, timer and the like.

The upper control unit 11 reads a character code included in print data received from a host computer (not shown), creates print image data by referring to a font memory, and stores the print image data in the RAM. Stored in the image memory of. If the print data received from the host computer is image data, the upper control unit 11 stores it in the image memory as it is, and if it is a graphic command, the upper control unit 11 edits and obtains it. The obtained image data is stored in the image memory.

When the engine control unit 12 receives a print instruction from the upper control unit 11 by the control signal 14, the engine control unit 12 heats the fixing device 15 until the temperature reaches a usable temperature.
Next, the driver 17 is driven to rotate the developing / transferring process motor 18, and at the same time, the charging high voltage power source 19 is turned on to charge the developing device 21. Next, the driver 23 is driven to rotate the paper feed motor 24 to suck and convey the paper.

When the paper reaches the printable point, the engine control unit 12 transmits the timing signal 26 and receives the video signal 27 to the upper control unit 11.
The video signal 27, which is edited page by page in the upper control unit 11 and received by the engine control unit 12, is transferred to the print data correction circuit 37 as the print data signal 32 via the buffer 33 for 9 lines. In the print data correction circuit 37, 9 dots around a specific dot,
That is, the matrix data of 9 × 9 dots is matched with the pattern stored in the print data correction circuit 37, and when they match, the corresponding dot data is transferred to the print head 35 as the actual print data signal 34. 1
When the transfer of the actual print data signal 34 for the line is completed,
A latch signal 36 is output to the print head 35 to hold the actual print data signal 34 in the print head 35.

The received actual print data signal 34 is received before the next print data is received from the host controller 11.
Are printed by the print head 35 receiving a print drive signal 38. The transmission and reception of the video signal 27 is performed for each print line. That is, the print head 35
The actual print data signal 34 held at is formed into a latent image as a dot having an increased potential on the photosensitive drum charged with a negative potential. Then, the image forming toner charged to the negative potential is attracted to each dot by an electric attraction force, and a toner image is formed.

After that, the toner image is sent to the transfer portion, and on the other hand, a high voltage power source 20 for transfer having a positive potential is generated by a transfer signal.
Is turned on, and the transfer device 22 transfers the toner image onto a sheet passing between the photoconductor drum and the transfer device 22. The sheet having the transferred toner image is brought into contact with the fixing device 15 and conveyed, and the toner image is fixed as an image by the heat of the fixing device 15. The sheet having the fixed image is further conveyed, passes through the sheet discharge port, and is discharged to the outside of the non-impact printer.

When the printing is completed and the sheet passes through the sheet discharge port, the application of the voltage to the developing device 21 by the high voltage power source 19 for charging is terminated, and at the same time, the rotation of the motor 18 for the developing / transferring process is stopped. ..

[0012]

However, in the above-mentioned conventional print control device, it is possible to set whether or not to perform smoothing only on a page-by-page basis. The part cannot be set not to be smoothed. Further, it is known that smoothing is very effective for characters and figures such as pie charts and line charts, but it is known to have an adverse effect for halftone and gradation patterns such as photographic images. For this reason, in a composite pattern in which a photographic image is added to characters and figures, it is necessary to sacrifice one of the grades for printing.

The present invention solves the problems of the conventional print control device described above, and can print a composite pattern in which a photographic image is added to a character or a figure with high quality. It is an object of the present invention to provide a print control device that enables smoothing and disables smoothing for print data outside the area.

[0014]

To this end, in the print control apparatus of the present invention, a higher-order control unit that edits print data page by page into a video signal, and a video data signal that receives the video signal. It has an engine control part which outputs as. A print data correction unit is provided, corrects the print data signal and outputs it as a corrected data signal, and outputs the print data signal as an original data signal without correction.

It is determined whether the print data is in a smoothing area. If the print data is in a smoothing area, the correction data signal is selected. If it is in a non-smoothing area, the original data signal is selected by the selection circuit. , And is transferred to the print head as an actual print data signal.

[0016]

According to the present invention, as described above, the high-order controller for editing the print data page by page into a video signal and the engine controller for receiving the video signal and outputting it as a print data signal are provided. .. A print data correction unit is provided, corrects the print data signal and outputs it as a corrected data signal, and outputs the print data signal as an original data signal without correction. The corrected data signal is used when smoothing and the original data signal is used when not smoothing.

It is determined whether the print data is for a smoothing area such as a character or a figure or a non-smoothing area such as a photographic image. If the print data is for a smoothing area, the correction data signal is for a non-smoothing area. , The original data signal is selected by the selection circuit and transferred to the print head as an actual print data signal.

The print head forms an electrostatic latent image on the photosensitive drum according to the actual print data signal.

[0019]

Embodiments of the present invention will now be described in detail with reference to the drawings. 1 is a control block diagram of a print control apparatus showing an embodiment of the present invention, FIG. 3 is a view showing an example of a composite pattern in which a photographic image is added to characters and figures, and FIG. 4 is a non-impact printer of the composite pattern of FIG. FIG. 5 is a diagram showing an example of a data command sequence when an attempt is made to print on the sheet, and FIG. 5 is a detailed diagram of the selection circuit of FIG.

In FIG. 3, 41 is a character, 42 is a graphic,
Reference numeral 43 is a photographic image. The composite pattern in which the photographic image 43 is added to the character 41 and the graphic 42 is printed by the data command sequence as shown in FIG. Reference numeral 44 is a character string, 45 is smoothing on in the case of raster image data of the graphic 42, and 46 is smoothing off in the case of raster image data of the photographic image 43. That is, even if the same raster image data is transmitted, it is possible to selectively use smoothing on and smoothing off depending on the contents of the image data such as the graphic 42 and the photographic image 43.

In FIG. 1, 10 is an interface, 1
Reference numeral 1 is a host control unit including a microprocessor, ROM, RAM, input / output port, timer and the like, and 12 is an engine control unit including a microprocessor, ROM, RAM, input / output port, timer and the like. The host controller 11 reads a character code included in print data received from a host computer (not shown),
The print image data is created by referring to the font memory, and the print image data is stored in the image memory in the RAM. If the print data received from the host computer is image data, the upper control unit 11 stores it in the image memory as it is, and if it is a graphic command, the upper control unit 11 edits and obtains it. The obtained image data is stored in the image memory.

When the engine control unit 12 receives a print instruction from the host control unit 11 by the control signal 14, the engine control unit 12 heats the fixing device 15 until the temperature reaches a usable temperature.
Next, the driver 17 is driven to rotate the developing / transferring process motor 18, and at the same time, the charging high voltage power source 19 is turned on to charge the developing device 21. Next, the driver 23 is driven to rotate the paper feed motor 24 to suck and convey the paper.

The engine control unit 12 transmits the timing signal 26 and receives the video signal 27 to the upper control unit 11 when the paper reaches the printable point.
The video signal 27, which is edited page by page in the upper control unit 11 and received by the engine control unit 12, is transferred to the print data correction circuit 37 as the print data signal 32 via the buffer 33 for 9 lines. In the print data correction circuit 37, 9 dots around a certain specific dot, that is, 9 × 9 dot matrix data is matched with the pattern stored in the print data correction circuit 37. The data is output to the selection circuit 52 as the correction data signal 51, but at the same time, the dot data of the specific dot itself, that is, the on / off state is output to the selection circuit 52 as the original data signal 53.

In the selection circuit 52, the engine control unit 12
In accordance with the selection control signal 55 received from the correction data signal 5
1 or the original data signal 53 is selected and transferred to the print head 35 as the actual print data signal 34. When the transfer of the actual print data signal 34 for one line is completed, the latch signal 36 is output to the print head 35, and the actual print data signal 34 is held in the print head 35.

Then, before the next print data is received from the upper control unit 11, the held real print data signal 34 is held.
Are printed by the print head 35 receiving a print drive signal 38. The transmission and reception of the video signal 27 is performed for each print line. That is, the print head 35
The actual print data signal 34 held at is formed into a latent image as a dot having an increased potential on the photosensitive drum charged with a negative potential. Then, the image forming toner charged to the negative potential is attracted to each dot by an electric attraction force, and a toner image is formed.

After that, the toner image is sent to the transfer portion, and on the other hand, a high voltage power source 20 for transfer having a positive potential is generated by a transfer signal.
Is turned on, and the transfer device 22 transfers the toner image onto a sheet passing between the photoconductor drum and the transfer device 22. The sheet having the transferred toner image is brought into contact with the fixing device 15 and conveyed, and the toner image is fixed as an image by the heat of the fixing device 15. The sheet having the fixed image is further conveyed, passes through the sheet discharge port, and is discharged to the outside of the non-impact printer.

When the printing is completed and the sheet passes through the sheet discharge port, the application of the voltage to the developing device 21 by the high voltage power source 19 for charging is finished and the rotation of the motor 18 for the developing / transferring process is stopped at the same time. .. Next, the operation of the selection circuit 52 will be described with reference to FIG. When a data command sequence as shown in FIG. 4 is transmitted from the host computer via the interface 10, the microprocessor of the host controller 11 analyzes the data command,
An area where smoothing is not performed (hereinafter referred to as “non-smoothing area”) is set for each page, and the engine control unit 12 is notified via a control signal 14.

The engine control unit 12 controls the raster counter 6 in the selection circuit 52 before the page printing is started.
1, the column counter 62 is reset, and the raster start address 63, the raster end address 64, the column start address 65, and the column end address 6 of the non-smoothing area are reset.
Set 6. Then, when printing of the page is started, the count values of the raster counter 61 and the column counter 62 are updated by the raster clock 71 and the column clock 72, respectively. The selector 73 checks whether the count value of the raster counter 61 is within the range of the raster start address 63 and the raster end address 64,
At the same time, it is checked whether or not the count value of the column counter 62 is within the range of the column start address 65 and the column end address 66. If both are within the range, it is determined that the area cannot be smoothed, and the original data signal 53 Is selected and transferred to the print head 35 as the actual print data signal 34.

If either or both of the count value of the raster counter 61 and the count value of the column counter 62 are out of the range, it is determined that the area is smoothed (hereinafter referred to as "smoothable area"). Then, the correction data signal 51 is selected and transferred to the print head 35 as the actual print data signal 34. In this way, smoothing can be performed in the non-smoothable area specified within one page without smoothing in the non-smoothable area specified. Also, the selector 7
It is possible to reverse the function of No. 3 to perform smoothing within the designated area and not perform smoothing outside the designated area.

Further, a plurality of combinations of the raster start address 63, the raster end address 64, the column start address 65 and the column end address 66 are provided, and a plurality of non-smoothing areas and a plurality of smoothing enable areas are designated within one page. You can also Next, a second embodiment will be described. FIG. 6 is a block diagram of a main part of a print control apparatus according to the second embodiment of the present invention.

In the figure, 11 is a host controller, 12 is an engine controller, and 75 is an operation panel. In this case, the designation of the non-smoothing area and the non-smoothing area can be performed by the operation panel 75 connected to the higher-level control unit 11, instead of the data command sequence from the host computer. It should be noted that the present invention is not limited to the above-described embodiments, and various modifications can be made based on the spirit of the present invention, and they are not excluded from the scope of the present invention.

[0032]

As described above in detail, according to the present invention, a host controller for editing print data page by page into a video signal, and receiving the video signal and outputting it as a print data signal. It has an engine control unit that operates. The print data correction means corrects the print data signal and outputs it as a corrected data signal, and outputs the print data signal as an original data signal without correction. Then, it is determined whether or not the print data is in a smoothing area, and if the print data is in a smoothing area, the correction data signal is selected, and if it is in a non-smoothing area, the original data signal is selected by the selection circuit. It is transferred to the print head as an actual print data signal.

Therefore, smoothing can be locally enabled or disabled within one page, and a composite pattern in which a photographic image is added to characters or graphics can be printed with high quality.

[Brief description of drawings]

FIG. 1 is a control block diagram of a print control apparatus according to an embodiment of the present invention.

FIG. 2 is a control block diagram of a conventional print control apparatus.

FIG. 3 is a diagram showing an example of a composite pattern in which a photographic image is added to characters and figures.

FIG. 4 is a diagram showing an example of a data command sequence when a non-impact printer is made to print the composite pattern of FIG.

5 is a detailed diagram of the selection circuit of FIG. 1. FIG.

FIG. 6 is a block diagram of a main part of a print control apparatus showing a second embodiment of the present invention.

[Explanation of symbols]

 11 Upper control unit 12 Engine control unit 27 Video signal 32 Print data signal 34 Actual print data signal 35 Print head 37 Print data correction circuit 51 Correction data signal 52 Selection circuit 53 Original data signal

Claims (1)

[Claims] 1. A high-level control section for editing print data page by page to produce a video signal, and (b) an engine control section for receiving the video signal and outputting it as a print data signal. ) A print data correction unit that corrects the print data signal and outputs it as a correction data signal, and also outputs the print data signal as an original data signal without correction, and (d) a print data smoothing area (E) A correction data signal is selected when it is in a smoothing area, and an original data signal is selected when it is in a non-smoothing area, and it is transferred to the print head as an actual print data signal. A printing control apparatus having a selection circuit for performing the printing.