JP2006159451A5

JP2006159451A5 -

Info

Publication number: JP2006159451A5
Application number: JP2004350303A
Authority: JP
Filing date: 2004-12-02
Publication date: 2008-01-24
Anticipated expiration: 2024-12-02

Claims

An image carrier, an exposure unit that exposes and scans light to the image carrier, and an image forming unit having a developing unit for visualizing the recording material with electrostatic latent image generated by exposure, in the conveying direction of the recording medium An image forming apparatus arranged along the line,
An image data storing means for storing the images data,
Exposure deviation amount storage means for storing exposure deviation amount information indicating the deviation amount with respect to the exposure scanning direction on the image carrier of each image forming unit;
Coordinate conversion means for converting the coordinates of the read address to the image data storage means based on the exposure deviation amount information stored in the exposure deviation amount storage means , and reading out the pixel data in accordance with the converted address information;
Buffer means for accumulating a plurality of lines of pixel data read by the coordinate conversion means;
The Based on the buffer means stored target pixel data to the pixel data groups around the target pixel data determining means for determining whether or not there is the image edge,
A first processing unit that performs halftone processing for the non-image edge on the target pixel data when the determination unit determines that the pixel is on the non-image edge;
A correction unit that corrects the gradation of the pixel-of-interest data stored in the buffer unit based on address information when the coordinate conversion unit performs conversion when the determination unit determines that the image edge exists. ,
Second processing means for performing edge processing on the pixel data obtained by the correction means to suppress the occurrence of discontinuity at edges different from the first processing means;
Before Symbol image forming apparatus pixel data obtained by the first and second processing means, and an outputting means for outputting as an exposure control signal of the exposure unit of the corresponding image forming unit.

The exposure deviation amount storage means includes
Storing position information relating to a plurality of positions in the main scanning direction, which is an ideal exposure scanning direction of the image carrier, and distance information relating to the distance between the ideal exposure scanning and the actual exposure at each position. The image forming apparatus according to claim 1.

The coordinate conversion means includes
Calculation means for calculating inclination information of exposure deviation in each region indicated by each position information based on the position information stored in the exposure deviation amount storage means and the distance information;
X address generating means for generating an X address in the main scanning direction which is the exposure direction from the previous image data storage means;
Each time the X address in the X address generator is updated, the region determining means for determining whether the X address is in the very region,
Selecting means for selecting the inclination information based on a result of determination by said area determination means, appropriate,
Adding means for accumulatively adding the inclination information selected by the selecting means;
Y address generating means for generating a Y address using the integer part of the result of addition by the adding means as an offset value of the Y address,
The correction unit generates pixel data after gradation correction based on data of two pixels continuous in the sub-scanning direction based on a value after the decimal point of the cumulatively added value of the addition unit. The image forming apparatus according to claim 2.

An image carrier, an exposure unit for exposing and scanning on the image bearing member, and an image forming unit having a developing unit for visualizing the recording material with electrostatic latent image generated by exposure, along the conveying direction of the recording medium A method for controlling image forming apparatuses arranged side by side,
And storing the images data into images data storage means,
A step of reading the exposure shift amount information from the exposure light shift amount storage means for storing an exposure deviation amount information indicating the amount of deviation with respect to the exposure scanning direction on the image carrier of each image forming unit,
A coordinate conversion step of converting the coordinates of the read address to the image data storage means based on the read exposure deviation amount information, and reading the pixel data according to the converted address information;
Storing pixel data read out in the coordinate conversion step in a buffer means for accumulating a predetermined number of lines;
On the basis of the buffer means stored target pixel data to the pixel data group of its periphery a determination step of determining the target pixel data whether the image edge,
A first processing step of performing halftone processing for the non-image edge on the pixel-of-interest data when it is determined by the determination step that the image is at the non-image edge;
A correction step of correcting the gradation of the pixel-of-interest data stored in the buffer unit based on address information when converted by the coordinate conversion unit when the determination unit determines that the image edge exists. ,
A second processing step for performing processing for an edge for suppressing occurrence of discontinuity at an edge different from the first processing means on the pixel data obtained in the correction step;
Method of controlling an image forming apparatus according to an outputting step of outputting the pixel data obtained in the previous SL first and second treatment steps, as an exposure control signal of the exposure unit of the corresponding image forming unit.

In the exposure deviation amount storage means,
Position information relating to a plurality of positions in the main scanning direction, which is an ideal exposure scanning direction of the image carrier, and distance information relating to the distance between the ideal exposure scanning and actual exposure at each position are stored. The method of controlling an image forming apparatus according to claim 4.

The coordinate conversion step includes
A calculation step of calculating inclination information of exposure deviation in each region indicated by each position information based on the position information stored in the exposure deviation amount storage means and the distance information;
An X address generation step of generating an X address in the main scanning direction which is the exposure direction from the previous image data storage means;
A step of determining which region the X address is calculated in the calculation step every time the X address is updated by the X address generation step;
A selection step of selecting corresponding inclination information based on the determined result;
An addition step of cumulatively adding the slope information selected in the selection step;
A Y address generation step of generating a Y address using the integer part of the result of addition in the addition step as an offset value of the Y address,
The correcting step generates pixel data after gradation correction based on data of two pixels continuous in the sub-scanning direction based on a value after the decimal point of the cumulatively added value of the adding step. The method for controlling an image forming apparatus according to claim 5.