KR20080029465A - Image forming apparatus - Google Patents

Abstract

An image forming apparatus is provided to configure a modulator in its designing and reduce the size and cost of a modulator chip and power consumption. A signal generating unit(100) outputs a plurality of color mode signals corresponding to a color mode and a plurality of black and white mode signals corresponding to a black and white mode. A modulator unit(200) performs modulation on the plurality of color mode signals and the black and white mode signals. A switching unit(300) selectively connects the signal generating unit and the modulator unit. A controller(400) controls the switching unit so that the plurality of the color mode signals or the plurality of black and white mode signals can be transferred to the modulator unit according to selection of the color mode or the black and white mode.

Description

Image Forming Apparatus}

1 is a control block diagram of an image forming apparatus according to the present invention;

2 is a view showing the operation of the switching unit according to an embodiment of the present invention.

Explanation of symbols on the main parts of the drawings

100: signal generator 200: modulator

300: switching unit 400: control unit

The present invention relates to an image forming apparatus, and more particularly, to an image forming apparatus using a modulator to obtain a high resolution output.

In general, a laser beam printer, which is one of the representative image forming apparatuses connected to a computer and prints desired information on a computer network, unlike a dot printer or an inkjet printer, forms a electrostatic latent image by scanning a laser beam on a charged photosensitive medium. Thereafter, the electrostatic latent image is developed into a visible image by toner, and an electrophotographic printing method of transferring and fixing on a printing paper is used.

In general, a color image forming apparatus refers to a device that transfers an image signal in the form of a visible image on a paper, which is a printing medium, according to a digital signal input from a computer or a scanner, and is usually a color laser printer. (color laser printer), color digital copier and multifunction printer.

On the other hand, conventional image forming apparatuses such as color laser printers and mono laser printers use a modulator to subdivide one dot into several pieces to obtain high resolution output.

In this case, since the conventional image forming apparatus uses one modulator for each beam, in the case of a recently developed high-performance mono laser printer, when eight beams are used, eight modulators also use a two-beam tandem color laser printer. In this case, eight modulators corresponding to the C (Cyan), M (Magenta), Y (Yellow), and K (Black) components are required, which are commonly used for 8-beam mono laser printers and 2-beam tandem color laser printers. In order to implement a modulator chip, it is cumbersome to require 14 modulators in all of the six modulators corresponding to the C, M, and Y components and the eight modulators corresponding to the K component.

Accordingly, an object of the present invention is to provide an image forming apparatus capable of selectively connecting a dot generator and a modulator using a switch according to the use of color and monochrome in a high performance printer.

According to an aspect of the present invention, there is provided an image forming apparatus comprising: a plurality of signal generators for outputting a plurality of color mode signals corresponding to a color mode and a plurality of monochrome mode signals corresponding to a black and white mode; A plurality of modulators each performing predetermined modulation on the plurality of color mode signals or the plurality of monochrome mode signals; A switching unit selectively connecting the plurality of signal generators and the plurality of modulators; And a controller configured to control the switching unit to transmit the plurality of color mode signals or the plurality of black and white mode signals to the plurality of modulators depending on whether the color mode or the black and white mode is selected. Achieved by an image forming apparatus.

Here, at least one of the plurality of monochrome mode signals may coincide with a part of the plurality of color mode signals.

The color mode may be a two-beam tandem mode using two beams for cyan, magenta, yellow, and black, respectively.

In addition, the monochrome mode may be an 8 beam mono mode.

Hereinafter, with reference to the accompanying drawings will be described an embodiment of the present invention;

As shown in FIG. 1, the image forming apparatus according to the present invention includes a signal generator 100, a modulator 200, a switching unit 300, and a controller 400 controlling the same.

The signal generator 100 may be implemented as a dot generator that generates dot size and position information of cyan, magenta, yellow, and black, which are color components.

Here, the dot generating unit may generate the dot size and position by the image data to be printed.

The modulator 200 includes a plurality of modulators that convert dot size and position information input from the signal generator 100 into an actual video output and subdivide one dot into several in order to obtain a high resolution output.

In this case, the modulator uses position data synchronized with the video clock to move the reference point to an asynchronous beam dector. The modulator may use a high frequency clock output from a ring oscillator designed to use a cell delay to subdivide one dot into several. At this time, the modulator needs one for each beam and turns on / off the beams at appropriate intervals so that each beam forms an image according to the data output from the dot generator.

The switching unit 300 may control the signal output from the signal generating unit 100 to be applied to the corresponding modulator of the modulator unit 200 under the control of the controller 400 to be described later, and may be implemented as a matrix switch.

The controller 400 controls the switching unit 300 to apply the dot position / dot size generated by the signal generator 100 to each modulator according to the type of the image forming apparatus.

According to an embodiment of the present invention, the controller 400 controls the switching unit 300 to configure the modulator unit 200 corresponding to the signal generator 100 according to the use of the image forming apparatus. For example, according to an embodiment of the present invention, when the image forming apparatus is a two-beam tentum color laser printer, which is a color laser printer using two beams, the controller 400 controls each color component C (cyan), M, etc. (magenta), Y (yellow), K (black) respectively control the switching unit 300 to be connected to the modulator.

Hereinafter, an image forming apparatus according to the present invention will be described as an example of being implemented as a two beam tantum color laser printer using two beams or an eight beam mono printer using eight beams.

As shown in FIG. 2, when the image forming apparatus is a 2-beam tandem color laser printer, the controller 400 may generate a signal generated by 110a which is a dot generator of the C component 110 of the signal generator 100. Signals generated at 0 210 and module 1 220 at 120a, which is the M component 120 dot generator, are generated at Module 2 230 and 3240, at 130a, which is the Y component 130 dot generator. The matrix switch is controlled such that the signal is applied to the module 4 (250) and the module 5 (260), and the signal generated at the 140a, which is the K component (140) dot generator, is applied to the module (6) 270 and the module 7 (280).

On the other hand, when the image forming apparatus is an 8 beam mono laser printer, the control unit 400 generates signals generated by the 140a, 140b, and six 140c, which are the dot generators of the K component 140 of the signal generator 100, respectively. The matrix switch is controlled to correspond to the module 0 210 to the module 7 280 of the 200.

Herein, in the present invention, the control unit 400 controls the switching unit 300 such that the dot generation units of the C, M, Y, and K components are sequentially connected to the seven modules from module 0, but the present invention is not limited thereto. As long as the dot generating unit and the modulator of the modulator unit 200 correspond one-to-one to each other, any combination can be used.

In addition, although the modulator unit 200 of the present invention includes eight modulators, the image forming apparatus of the present invention is a two-beam tandem color laser printer and an eight-beam mono laser printer, but the control unit 400 generates a signal. If the unit 100 and the modulator unit 200 can control the switching unit 300 to have a one-to-one correspondence, the number of dot generating units is not limited.

Although some embodiments of the invention have been shown and described, it will be apparent to those skilled in the art that modifications may be made to the embodiment without departing from the spirit or spirit of the invention. . It is intended that the scope of the invention be defined by the claims appended hereto and their equivalents.

As described above, according to the present invention, an image forming apparatus capable of selectively connecting a dot generator and a modulator by using a switch according to the use of color and monochrome in a high performance printer is provided. Accordingly, in designing the modulator, it is possible to flexibly configure and reduce the size, price, power consumption, etc. of the modulator chip.

Claims (4)

In the image forming apparatus, A plurality of signal generators for outputting a plurality of color mode signals corresponding to the color mode and a plurality of black and white mode signals corresponding to the black and white mode; A plurality of modulators each performing predetermined modulation on the plurality of color mode signals or the plurality of monochrome mode signals; A switching unit selectively connecting the plurality of signal generators and the plurality of modulators; And a controller configured to control the switching unit to transmit the plurality of color mode signals or the plurality of black and white mode signals to the plurality of modulators depending on whether the color mode or the black and white mode is selected. Image forming apparatus. The method of claim 1, And at least one of the plurality of monochrome mode signals coincides with a portion of the plurality of color mode signals. The method of claim 1, The color mode is a two-beam tandem mode using two beams for cyan, magenta, yellow, and black, respectively. The method of claim 1, And the monochrome mode is an 8 beam mono mode.

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