JP2005303882A - Image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enhance intra-picture density non-uniformity caused by an edge effect, a sweep-in phenomenon and the like in an image formed by an electro-photograph process. <P>SOLUTION: An edge in image information is detected and for a predetermined region which includes the edge and is close to the edge, the quantity of toner placed thereon is adjusted using laser light quantity modulation, pulse width modulation and the like. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an image processing apparatus and a control method thereof, and more particularly to an image processing apparatus that forms a visible image on a predetermined recording medium according to input information.

  2. Description of the Related Art Conventionally, an image forming apparatus using an electrophotographic method such as a laser beam printer is encoded with commands related to printing (printing commands, commands for specifying a printing state of a printer, etc.) and codes from an external information processing device such as a personal computer or a workstation. After the character and graphic information is received by the data receiving means, the code information is converted into pixel information by the pixel converting means, and this is converted into raster information. Further, the raster information is converted into, for example, a semiconductor laser. An electrostatic latent image is formed by performing a raster scan on a photoconductor that is uniformly charged in advance by a light modulation scanning means including a rotating polygon mirror such as a polygon mirror after intensity modulation by a light output means. It has an electrophotographic engine for forming a desired image on a recording material by an electrophotographic process. It is carried out cement.

  For example, an electrophotographic image forming apparatus using an electrophotographic process such as a laser beam printer or a copying machine uses a powdery developer (hereinafter referred to as toner).

  The toner is accommodated in the developing container, conveyed to the toner carrier by the toner conveyance means, and held on the toner carrier. Then, a predetermined charge is applied by a toner layer thickness regulating member (hereinafter referred to as a doctor blade), and the electrostatic layer is moved to an electrostatic latent image forming unit on an image carrier (hereinafter referred to as a photoreceptor) that carries an image. Visualize the electrostatic latent image on the photoreceptor. Thereafter, the visible image is transferred to a transfer material such as paper by a transfer means and fixed by a fixing device. The toner remaining on the image carrier without being transferred to the transfer material is peeled off from the image carrier by a cleaning member in contact with the image carrier and sent to the cleaning container.

  In addition, in order to improve the fixing performance of the toner (to enable fixing at a low fixing temperature), the binder thermal characteristics and wax thermal characteristics are improved to control the melt viscoelasticity of the toner to increase the viscosity. ing.

  As one development method, a jumping development method is known in which a latent image on an image carrier is developed while a developer carrier of the image forming apparatus is held in contact with the image carrier. An image forming apparatus employing a jumping development method will be described.

  In the image forming apparatus, the toner accommodated in the developing container is held on a developer carrying member (hereinafter referred to as a developing sleeve), and the developing sleeve rotates so that the held toner becomes a photosensitive member as an image carrying member. It is conveyed toward the developing area facing the body. During the conveyance, the toner is regulated by a doctor blade in contact with the developing sleeve, and is applied in a thin layer on the developing sleeve. In the developing region, the developing sleeve and the photoconductor are held with a gap of 50 to 500 μm, and a thin layer is formed on the developing sleeve by applying a developing bias in which a direct current is superimposed on the developing sleeve by a bias power source. The toner applied to the toner flies and adheres to the electrostatic latent image on the photoreceptor, and the latent image is visualized as a toner image.

  The developing bias is similarly applied to non-printing areas such as between sheets.

  Next, in order to fix the image formed on the transfer material with the toner, a fixing device having a heating unit is used. Currently, fixing devices widely used include a fixing roller in which a halogen lamp as a heat source is inserted in a roller provided with a release layer made of a PFA tube on an aluminum core, and a core. The pressure roller is provided with an elastic layer made of silicone rubber and a releasable layer made of PFA tube. Fixing is completed by applying heat and pressure to the unfixed toner on the recording material at the nip portion.

  Further, in an on-demand type fixing device using a heat-resistant thin film instead of the fixing roller, a silicone rubber roller having a release layer on the surface is used as a pressure roller. The on-demand heating means is composed of a heater substrate, a heating resistor, a surface protective layer, a thermistor, and a film guide member. The heat-resistant thin film is conveyed to the heating portion by a driving roller and a driven roller, and a nip with the pressure roller. Fixing is performed at the part.

Thus, a series of image forming processes is completed, and the user can obtain a desired image on a desired transfer material.
JP 2003-173055 A

  In recent image forming apparatuses, high definition and high resolution have been required. Therefore, it is essential that one dot or fine line can be faithfully reproduced and no image defect occurs. However, in the image forming apparatus using the conventional development, when an image of M × N dots is developed, the toner amount is not necessarily uniform. Since the electric field is engulfed from the periphery at the edge portion of the latent image, the so-called edge effect that the electric field strength becomes strong, or the toner that did not sufficiently act on the developing device is left at the downstream edge of the electrostatic latent image, In particular, in jumping development, even if the electrostatic latent image on the drum passes through the development region D, toner slightly flies from the developer carrier to the latent image. In the vicinity of the downstream side in the rotation direction, a phenomenon such as so-called sweeping in which the toner amount increases particularly occurs.

  Due to these phenomena, there are problems such as density unevenness in solid images and deterioration of OHT permeability due to excessive toner amount in a color image forming apparatus. Therefore, the present invention according to the present application aims to solve such problems.

  The above object is achieved by the image forming apparatus according to the present invention.

The first invention includes at least an image carrier, a developer, a developer carrier that carries the developer and transports it to the development area, and abuts on the developer carrier to regulate the amount of the developer applied. And a developer carrying member that carries the developer and transports it to the development region, and applies a developing bias to the developer carrying member on the electrostatic latent image formed on the image carrier. Has a developing device that develops and visualizes by applying,
An unfixed image using a developer is formed on a predetermined recording medium based on information input from the host device, and the developer is firmly fixed on the recording medium by passing the unfixed image through a fixing device. An image processing apparatus characterized by
The image processing apparatus is characterized in that an input image information has an image pattern having a predetermined density and area, detects an edge portion of the image, and thins out image information in the vicinity of the edge portion including the edge portion.

  This can improve toner non-uniformity due to the edge effect particularly in the image edge portion.

The second invention is
At least an image carrier, a developer, a developer carrier that is not in contact with the image carrier that carries the developer and transports it to the development area, and a coating of the developer that is in contact with the developer carrier A regulating member that regulates the amount, and the developer carrying member carries the developer and transports it to the developing region, and the electrostatic latent image formed on the image carrying member is transferred to the developer carrying member. Has a developing device that develops and visualizes by applying a developing bias,
An unfixed image using a developer is formed on a predetermined recording medium based on information input from the host device, and the developer is firmly fixed on the recording medium by passing the unfixed image through a fixing device. An image processing apparatus characterized by
The image processing apparatus is characterized in that an input image information has an image pattern having a predetermined density and area, detects an edge portion of the image, and thins out image information in the vicinity of the edge portion including the edge portion.

  Thereby, in the image processing apparatus using the jumping development method, it is possible to improve toner non-uniformity due to the edge effect particularly in the image edge portion.

The third invention is
At least an image carrier that is a rotating member that forms an electrostatic latent image on the surface, and a developer that rotates the image carrier and conveys the electrostatic latent image forming unit to a development area to develop the electrostatic latent image. A developer carrying member that carries the developer and conveys the developer to the development area; and a regulating member that abuts on the developer carrying member and regulates the amount of the developer applied. Has a developing device that carries the developer and transports it to the development area, and develops and visualizes the electrostatic latent image formed on the image carrier by applying a developing bias to the developer carrier,
An unfixed image using a developer is formed on a predetermined recording medium based on information input from the host device, and the developer is firmly fixed on the recording medium by passing the unfixed image through a fixing device. An image processing apparatus characterized by
In the image pattern in which the input image information has a predetermined density and area and at least a part on the recording medium, an image edge portion on the downstream side with respect to the rotation direction of the image carrier is detected, and the downstream edge portion is detected. An image processing apparatus characterized by thinning out image information in the vicinity of the downstream edge portion.

  This can improve toner non-uniformity caused by so-called sweeping particularly at the downstream end of the image.

The fourth invention is:
At least an image carrier that is a rotating member that forms an electrostatic latent image on the surface, and a developer that rotates the image carrier and conveys the electrostatic latent image forming unit to a development area to develop the electrostatic latent image. A developer carrying member that contacts the image carrying member that carries the developer and transports it to the development area, and a regulating member that contacts the developer carrying member and regulates the amount of the developer applied. The developer carrying member carries the developer and transports it to the development area, and the electrostatic latent image formed on the image carrying member is developed and visualized by applying a developing bias to the developer carrying member. A developing device,
An unfixed image using a developer is formed on a predetermined recording medium based on information input from the host device, and the developer is firmly fixed on the recording medium by passing the unfixed image through a fixing device. An image processing apparatus characterized by
In the image pattern in which the input image information has a predetermined density and area and at least a part on the recording medium, an image edge portion on the downstream side with respect to the rotation direction of the image carrier is detected, and the downstream edge portion is detected. An image processing apparatus characterized by thinning out image information in the vicinity of the downstream edge portion.

  Thereby, in an image processing apparatus using a non-contact development method such as a jumping development method, toner non-uniformity due to so-called sweeping at the downstream end of the image can be improved.

  According to the present invention, by performing image processing on the image edge portion and reducing the height of the edge portion, density unevenness in the image edge portion is improved and good density uniformity is obtained in an image forming apparatus in which the edge effect is remarkable. It is done. Further, the transmission uniformity and transparency of color images on OHT are also improved. In addition, image processing is performed only on the downstream edge of the image and the height of the downstream edge is reduced, thereby improving density unevenness in the downstream edge of the image forming apparatus in which the sweeping phenomenon and the like are prominent, and good density uniformity. Sex is obtained. Similarly, transmission uniformity and transparency of a color image on OHT are also improved.

  Hereinafter, the best mode for carrying out the present invention will be described in detail with reference to examples.

(First embodiment)
FIG. 1 is a configuration diagram of an electrophotographic printer of the present invention.

  An electrophotographic cartridge 1 is formed by integrating an electrophotographic photosensitive member 2, a charging roller 3, a developing device 4, and a cleaner 5. The electrophotographic photosensitive member 2 is formed of a photosensitive material such as OPC, amorphous Se, or amorphous Si on a cylindrical substrate such as aluminum or nickel, and is referred to as a photosensitive drum. Uniform charging is performed on the photosensitive drum 2 by the charging roller 3. Next, the image signal is raster-scanned by the laser scanner 6 and exposed. The laser scanner 6 scans the blinking of the semiconductor laser with a polygon scanner, and forms an optical spot image on the photosensitive drum by an optical system and a folding mirror. This creates an electrostatic latent image. The produced electrostatic latent image is developed by the developing device 4. For development, jumping development, two-component development, FEED development, or the like is used. The laser is turned on to record, image exposure to eliminate the latent image charge, and reversal development to attach toner to the one with less charge. Often used in combination.

  The developed image is transferred to a transfer material. The transfer material is stored in a cassette 8 and is fed one by one by a paper feed roller 9. When a print signal is sent from the host device, the paper is fed by the paper feed roller 9, and the toner image is transferred onto the transfer material by the transfer roller 11 in synchronization with the image signal by the timing roller 10. The transfer roller 11 is an elastic body having low conductivity and is electrostatically transferred by a bias electric field at a nip portion formed by the photosensitive drum 2 and the transfer roller 11.

  The transfer material onto which the image has been transferred is sent to a nip portion between the pressure roller 13 and the film 12 in the fixing device 14 and fixed. The fixed transfer material is fed by the paper discharge roller 16 and discharged to the paper discharge tray 7. On the other hand, the toner remaining after transfer is cleaned by a blade in the cleaner 5.

  The laser driver 15 controls the emission intensity and emission duty of the semiconductor laser of the laser scanner 6.

  The bias applied to the charging roller 3, the bias applied to the developing device 4, and the bias applied to the transfer roller 11 are supplied by a transfer high-voltage device 17. A main motor and a scanner motor (not shown) are also controlled by a motor control unit (not shown).

  The fixing device 14 includes a film 12 in which a pressure roller 13 and a heating means such as a heater are inscribed, and the temperature of the fixing device heater is controlled by a fixing control unit (not shown). The operations of the paper feed roller 9 and the timing roller 10 are controlled by a paper feed control unit (not shown).

  The developing device 4 employs a non-contact developing method and will be described with reference to FIG.

  The developing device 4 includes a developing sleeve 19 and a developing container 20 that are toner carriers that carry the toner 18 and convey it to the photoreceptor 2.

  In the developing container 20, there is a stirring member 21 for stirring the toner 18 and feeding it in the direction of the developing sleeve 19, which is rotating.

  The developing sleeve 19 is obtained by coating a base tube with a paint in which carbon is dispersed, and is nonmagnetic. The base tube is made of aluminum, stainless steel, or the like. Further, the surface of the developing sleeve 19 has a roughness due to the paint coating, and the roughness contributes to toner conveyance of the developing sleeve 19.

  Further, the developing sleeve 19 is rotatably supported by a bearing (not shown), and is rotated from the photosensitive member 2 through a gear (not shown) in a direction indicated by an arrow b. Further, the developing sleeve 19 is connected to a developing high-voltage device 22 that can superimpose an AC bias on a DC bias, and a latent image on the photoreceptor 1 is visualized as a toner image by applying a bias by a power source 22. Further, the developing sleeve 19 has a diameter of 16 mm and is supported to be opposed to the photoreceptor 2 with a predetermined developing interval.

  In this embodiment, the doctor blade 23 that is a toner layer thickness regulating member that regulates the layer thickness of the toner 18 on the developing sleeve 19 applies an appropriate tribo to the toner 18 by frictional charging. The toner 18 is a magnetic one-component negative toner.

  The doctor blade 23 is installed so that the urethane rubber contacts the developing sleeve 19 with a contact force P (contact load gf / cm per cm in the longitudinal direction of the sleeve) of 35 gf / cm.

  The sheet metal 24 is fixed to the developing device 4.

  A magnet roller 25 is fixedly disposed inside the developing sleeve 19.

  The magnet roller 25 in the developing sleeve 19 has four magnetic poles. Of the four magnetic poles, the S1 pole is disposed opposite to the photoreceptor 2, and the toner that causes fogging when the toner 18 flies on the photoreceptor 1 and is developed is developed to the developing sleeve. 19 is necessary to keep it on the surface. The S2 pole is disposed on the opposite side of the S1 pole, and has a function of adsorbing the toner 18 of the developing container 4 to the developing sleeve 19 and circulating the toner 18 in the vicinity thereof as the developing sleeve 19 rotates. . This circulation contributes to the tribo application of the toner 18. Both the N1 and N2 poles contribute to the transport of toner 18 coated on the developing sleeve 19 and the provision of tribo. In this embodiment, a magnet roller having a four-pole configuration is used. However, the number of poles is not limited to four if there is a pole that performs the above function.

  Incidentally, a toner blowing prevention sheet 26 is provided on the inner side of the developing container 4 corresponding to the lower portion of the developing sleeve 10 to prevent toner leakage from the lower portion of the developing sleeve.

  In the present embodiment, using the electrophotographic printer as described above, the edge portion of the solid image is detected, and image correction using image processing is performed on the edge vicinity region including each edge portion. The present invention is particularly effective when the density unevenness of the edge portion where the density of the solid image edge portion becomes deep due to the edge effect or the like is remarkable.

Specifically, FIG. 4 main scanning direction and FIG. 5 sub-scanning direction roughly show the relationship between the developed toner image sectional view on the conventional drum and the toner image sectional view according to the present invention. As shown in these figures, the electrostatic latent image on the drum is corrected by image processing for the portion that rises due to the edge effect in the toner image, and the toner height of the developed toner image cross section is as much as possible. Make it uniform.
Actually, an example of printing image data of main scanning direction 230 dots × sub-scanning direction 255 dots where 1200 dpi outermost shell is all black will be described. The image information is processed according to the flow of FIG.

  First, it is determined whether the image is multi-valued (10 dots or more) with respect to m dots in the main scanning direction. By the way, for less than 10 dots, correction is not performed because density unevenness cannot be confirmed with the naked eye. Next, the edge portion in the sub-scanning direction of the image is detected and the image is corrected.

  In addition, what is necessary is just to comprise by a primary differentiation circuit or a secondary differentiation circuit in order to detect an edge. For example, a window having an appropriate size including the target pixel is prepared, and the highest density and the lowest density are detected. If the difference is equal to or larger than a predetermined value, it is determined that the target pixel exists at the edge portion.

  The number of dots to be corrected is, in principle, m × n (m and n are both 10 or more) dot images, m × 0.1 dots from the respective edges in the main scanning direction printed on the transfer material, and the sub scanning direction. Limited to n × 0.1 dots from each edge. However, the upper limit of the number of dots to be corrected is 25 dots in both the main scanning direction and the sub-scanning direction, and correction is not performed for areas exceeding that. The upper limit of 25 dots almost coincides with the maximum area where the density unevenness of the edge portion becomes obvious. In the present embodiment, the maximum area where the density unevenness of the edge portion becomes apparent using a solid black image in the range of 1 mm × 1 mm square to 100 mm × 100 mm square is in the range of about 0.55 mm from the image edge, and 10 mm × After the pattern larger than 10 mm square, there was almost no change and the maximum value. Therefore, the upper limit to be corrected was set to a value (25 dots≈0.56) corresponding to the distance from the edge of 0.55 mm and having a slight margin.

  In other words, in the solid black print image data of 230 dots in the main scanning direction × 255 dots in the sub scanning direction as shown in FIG. 3, 23 dots are corrected from each left and right edge in the main scanning direction, and 25 dots are corrected from each vertical edge in the sub scanning direction. .

  As a correction method, laser light amount modulation is performed. The first to the tenth from the edge are set to output 80% of laser light, and the eleventh to 25th are set to output 90% of laser light. However, the first dot here is a dot at the edge portion, and the laser light quantity when correction is not performed is 100%. As a correction method, the laser light amount modulation is performed in this embodiment. However, in addition to the laser light amount modulation, the laser pulse width modulation or the laser light amount modulation and the laser pulse width modulation may be combined. . The effects of this example are shown in the following table.

  The edge density unevenness in Table 1 is a result of visually confirming the presence or absence of density unevenness at the edge using an image after fixing on 5 mm square and 10 mm square plain paper (PBSK 64 g paper A4). The image density was also measured as an average density in a 5 mm × 5 mm area with a reflection densitometer (Macbeth) using 5 mm square and 10 mm square after fixing on plain paper (PBSK 64 g paper A4). When placed on a 10 mm square, measurement was performed at five points as shown in FIG.

  As can be seen from the above results, in this example, the density unevenness of the edge portion was improved and the uniformity of the image density was obtained as compared with the conventional example in which the image correction of the region including the edge portion was not performed. I understand.

  In this embodiment, the jumping development method in which the developer carrying member is not in contact with the drum is used as an example. However, if the development method reveals uneven density at the edge, such as a contact development method, the same applies. Needless to say, it has a great effect.

  The image edge portion processing method is not limited to this as long as the effect that the outer shape of the toner on the paper is the same as that shown in FIGS. 4B to 5B can be obtained. In this embodiment, correction is performed for all image edge portions on the paper surface. However, when the region where the density unevenness of the edge portion is limited to a specific partial width, at least one of the specific portions is corrected. It suffices to perform correction only on the part.

  Further, in the present embodiment, a monochrome (black and white) image forming apparatus is used as an example, but the same effect is exhibited for a color image forming apparatus, and the density unevenness of the edge portion is improved. Needless to say, the transmission uniformity and transparency of the color image on the OHT sheet are also improved.

  Further, the resolution and process speed of the image device are not limited to the above.

(Second embodiment)
The second embodiment of the present invention will be described below. Since the image forming apparatus to which the second embodiment is applied is the same as that of the first embodiment, description thereof is omitted.

  In this embodiment, the edge portion of the solid image is detected, and image correction using image processing is performed only on the region near the image downstream edge including the image downstream edge portion located downstream with respect to the drum rotation direction. The present invention is particularly effective when the density unevenness of the downstream edge portion where the density of the solid image edge portion becomes deep due to sweeping or the like is remarkable.

  Specifically, FIG. 8 schematically shows a relationship between a developed toner image sectional view on a conventional drum and a toner image sectional view according to the present invention. As shown in these drawings, the electrostatic latent image on the drum is corrected by image processing for the portion where the toner at the edge portion in the toner image swells, and the toner height of the developed toner image cross section is corrected. To be as uniform as possible.

  Actually, an example of printing image data of main scanning direction 250 dots × sub-scanning direction 500 dots where the 1200 dpi outermost shell is all black will be described. The image information is processed according to the flow of FIG.

  First, it is determined whether the image is multi-valued (10 dots or more) with respect to m dots in the main scanning direction. By the way, for less than 10 dots, correction is not performed because density unevenness cannot be confirmed with the naked eye. Next, the edge portion in the sub-scanning direction of the image is detected and the image is corrected.

  In addition, what is necessary is just to comprise by a primary differentiation circuit or a secondary differentiation circuit in order to detect an edge. For example, a window having an appropriate size including the target pixel is prepared, and the highest density and the lowest density are detected. If the difference is equal to or larger than a predetermined value, it is determined that the target pixel exists at the edge portion.

  In principle, the number of dots to be corrected is limited to n × 0.25 dots from each edge in the sub-scanning direction printed on the transfer material in the case of an m × n dot image. However, the upper limit of the number of dots to be corrected is 50 dots, and correction is not performed for an area exceeding that. The upper limit of 50 dots substantially coincides with the maximum area where density unevenness in the downstream edge portion becomes apparent. In the present embodiment, the maximum area where the density unevenness in the downstream edge portion appears using a solid black image in the range of 1 mm × 1 mm square to 100 mm × 100 mm square is a range of about 1.0 mm from the image edge, and is 10 mm. After the pattern larger than × 10 mm square, it was almost unchanged and was the maximum value. Therefore, the upper limit for correction is 1.0. A value corresponding to mm and having a margin (50 dots≈1.1) was used.

  In other words, in the solid black print image data of 250 dots in the main scanning direction × 500 dots in the sub scanning direction as shown in FIG. 9, 50 dots are corrected from the downstream edge in the sub scanning direction.

  As a correction method, laser light amount modulation is performed. The first to fifteenth from the edge are set to output 80% of laser light, the sixteenth to thirtyth are set to output 85% of laser light, and the 31st to 50th are set to output 90% of light. However, the first dot here is a dot at the edge portion, and the laser light quantity when correction is not performed is 100%. As a correction method, the laser light amount modulation is performed in this embodiment. However, in addition to the laser light amount modulation, the laser pulse width modulation or the laser light amount modulation and the laser pulse width modulation may be combined. . The effects of this example are shown in Table 2 below.

  The edge density unevenness in Table 1 is a result of visually confirming the presence or absence of density unevenness at the edge using an image after fixing on 5 mm square and 10 mm square plain paper (PBSK 64 g paper A4). The image density was also measured as an average density in a 5 mm × 5 mm area with a reflection densitometer (Macbeth) using 5 mm square and 10 mm square after fixing on plain paper (PBSK 64 g paper A4). When placed on a 10 mm square, measurement was performed at five points as shown in FIG.

  As can be seen from the above results, in this example, the density unevenness in the downstream edge portion was improved and the uniformity of the image density was obtained as compared with the conventional example in which the image correction of the region including the edge portion was not performed. I understand.

  In this embodiment, a jumping development method in which the developer carrying member, which is a development method in which the sweeping phenomenon toward the downstream of the image relatively easily manifests as density unevenness in the downstream edge portion, is not in contact with the drum is used as an example. However, it goes without saying that the present invention exerts the same effect in the contact development method and the like, and the same effect can be achieved as long as the development method in which the density unevenness in the downstream edge portion becomes apparent.

  The image edge processing method is not limited to this as long as the effect that the outer shape of the toner on the paper is the same as that shown in FIG. In this embodiment, correction is performed for all image edge portions on the paper surface. However, when the region where the density unevenness of the edge portion is limited to a specific partial width, at least one of the specific portions is corrected. It suffices to perform correction only on the part.

  Further, in the present embodiment, a monochrome (black and white) image forming apparatus is used as an example, but the same effect is exhibited for a color image forming apparatus, and density unevenness in the downstream edge portion is improved. Needless to say, the transmission uniformity and transparency of the color image on the OHT sheet are also improved.

  Further, the resolution and process speed of the image device are not limited to the above.

Configuration diagram of electrophotographic printer of the present invention Diagram showing the configuration of the jumping developing device The figure which shows the correction | amendment classification of the main scanning 255 dot x sub-scanning 230 dot image by 1st Example of this invention. The figure which compared the cross section of the main scanning direction of the toner image by the 1st Example of this invention, and the conventional cross section. The figure which compared the cross section of the subscanning direction of the toner image by the 1st Example of this invention, and the conventional cross section. Flowchart of image correction control in the first embodiment of the present invention The figure which showed the density measurement area division of solid black 10mm square The figure which compared the cross section of the subscanning direction of the toner image by the 2nd Example of this invention, and the conventional cross section. Correction classification of main scanning 250 dot × sub-scanning 500 dot image according to the second embodiment of the present invention Flowchart of image correction control in the first embodiment of the present invention

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Electrophotographic cartridge 2 Electrophotographic photosensitive member 3 Charging roller 4 Developer 5 Cleaner 6 Laser scanner 7 Paper discharge tray 8 Paper feed cassette 9 Paper feed roller 10 Timing roller pair 11 Transfer roller 12 Fixing film 13 Pressure roller 14 Fixing device 15 Laser driver 16 Paper discharge roller 17 Transfer high pressure device 18 Toner 19 D sleeve (developing sleeve)
20 Development container 21 D stirring member 22 Development high pressure device (power supply)
23 Doctor blade 24 Sheet metal 25 Magnet roller

Claims (4)

At least an image carrier, a developer, a developer carrier that carries the developer and transports it to the development area, and a regulating member that abuts on the developer carrier and regulates the amount of the developer applied. The developer carrying body carries the developer and transports it to the development area, and develops the electrostatic latent image formed on the image carrying body by applying a developing bias to the developer carrying body, Having a developing device for visualization;
An unfixed image using a developer is formed on a predetermined recording medium based on information input from the host device, and the developer is firmly fixed on the recording medium by passing the unfixed image through a fixing device. An image processing apparatus characterized by
An image processing apparatus, wherein input image information detects an edge portion of an image in an image pattern having a predetermined density and area, and thins out image information in the vicinity of the edge portion including the edge portion. At least an image carrier, a developer, a developer carrier that is not in contact with the image carrier that carries the developer and transports it to the development area, and a coating of the developer that is in contact with the developer carrier A regulating member that regulates the amount, and the developer carrying member carries the developer and transports it to the developing region, and the electrostatic latent image formed on the image carrying member is transferred to the developer carrying member. Has a developing device that develops and visualizes by applying a developing bias,
An unfixed image using a developer is formed on a predetermined recording medium based on information input from the host device, and the developer is firmly fixed on the recording medium by passing the unfixed image through a fixing device. An image processing apparatus characterized by
An image processing apparatus, wherein input image information detects an edge portion of an image in an image pattern having a predetermined density and area, and thins out image information in the vicinity of the edge portion including the edge portion. At least an image carrier that is a rotating member that forms an electrostatic latent image on the surface, and a developer that rotates the image carrier and conveys the electrostatic latent image forming unit to a development area to develop the electrostatic latent image. A developer carrying member that carries the developer and conveys the developer to the development area; and a regulating member that abuts on the developer carrying member and regulates the amount of the developer applied. Has a developing device that carries the developer and transports it to the development area, and develops and visualizes the electrostatic latent image formed on the image carrier by applying a developing bias to the developer carrier,
An unfixed image using a developer is formed on a predetermined recording medium based on information input from the host device, and the developer is firmly fixed on the recording medium by passing the unfixed image through a fixing device. An image processing apparatus characterized by
In the image pattern in which the input image information has a predetermined density and area and at least a part on the recording medium, an image edge portion on the downstream side with respect to the rotation direction of the image carrier is detected, and the downstream edge portion is detected. An image processing apparatus characterized by thinning out image information in the vicinity of the downstream edge portion. At least an image carrier that is a rotating member that forms an electrostatic latent image on the surface, and a developer that rotates the image carrier and conveys the electrostatic latent image forming unit to a development area to develop the electrostatic latent image. A developer carrying member that contacts the image carrying member that carries the developer and transports it to the development area, and a regulating member that contacts the developer carrying member and regulates the amount of the developer applied. The developer carrying member carries the developer and transports it to the development area, and the electrostatic latent image formed on the image carrying member is developed and visualized by applying a developing bias to the developer carrying member. A developing device,
An unfixed image using a developer is formed on a predetermined recording medium based on information input from the host device, and the developer is firmly fixed on the recording medium by passing the unfixed image through a fixing device. An image processing apparatus characterized by
In the image pattern in which the input image information has a predetermined density and area and at least a part on the recording medium, an image edge portion on the downstream side with respect to the rotation direction of the image carrier is detected, and the downstream edge portion is detected. An image processing apparatus characterized by thinning out image information in the vicinity of the downstream edge portion.

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