Canon Kabushiki Kaisha

Tetsuya Atsumi

Nobuatsu Sasanuma

Yuichi Ikeda

Hisashi Fukushima

Tomohito Ishida

Masatsugu Toyonori

Isami Itoh

Yasuhiro Saito

Yukio Nagase

Rie Saito

Kunitoshi Aoki

Tetsuya Nakamura

Toshimitsu Danzuka

Shingo Ito

Haruhiko Moriguchi

Takahiro Kubo

Yuichiro Toyohara

Takashi Kawai

Yukio Watanabe

Tsunao Honbo

Megumi Uchino

Shunichi Takada

Yasuhiro Saitou

An image forming apparatus that can reduce a toner bearing amount stably regardless of a density of an image. The image forming apparatus comprises a first generating unit which generates a reference pattern, and a second generating unit which generates, based on image data, a correction pattern for thinning out dots at a region from halftone density to high density. The image data is converted based on the reference pattern generated by the first generating unit and the correction pattern generated by the second generating unit. The image forming apparatus further comprises a photoreceptor. The photoreceptor is charged, the charged photoreceptor is exposed based on the converted image data to form an electrostatic latent image, and the electrostatic latent image is developed.

Image forming apparatus and image forming method for reducing toner bearing amount, and storage medium thereof

A toner amount measuring unit irradiates a toner image formed on an image carrying member with light, and an image capturing unit captures an image of a reflected waveform according to light reflected by the toner image. Then, an amount of applied toner is calculated based on the peak position or peak height of the reflected waveform in accordance with information associated with the density of the toner image to be formed.

Measuring apparatus, measuring method and image forming apparatus

An image forming apparatus includes an image bearing member for bearing an electrostatic latent image; a charger for electrically charging the image bearing member by contact of electroconductive magnetic particles carried on a magnetic particle carrying member with the image bearing member; a developing device for developing the electrostatic latent image into a toner image by supplying toner to the electrostatic latent image; a layer thickness detecting device for detecting a thickness of a surface layer of the image bearing member; a supplying device for supplying the magnetic particles to the magnetic particle carrying member with predetermined timing; and a control device for controlling a supply amount of the magnetic particles so that the supply amount of the magnetic particles supplied by the supplying device increases with an increase of an amount of change in thickness, in terms of an absolute value, of the surface layer obtained from a detection result of the layer thickness detecting device.

Image forming apparatus including image bearing member surface abrassion control feature

An image heating apparatus for allowing a surface of a heated toner image borne on a recording material to be glossed without generating a batter in the heated toner image is provided. In an image heating apparatus () including heating means (and) for heating an unfixed toner image (ta) borne on a recording material (P) and pressure means (and) for pressurizing an unfixed toner image (tb) heated by the heating means to gloss a surface of the unfixed toner image, the pressure means includes: pressure force changing means (L andR) for changing a pressure force when the pressure means pressurizes the unfixed toner image; temperature detecting means (and) for detecting a temperature of the pressure means; and pressurization control means (). The pressurization control means controls the pressure changing means according to temperature information of the temperature detecting means to change the pressure force of the pressure means before the pressure means pressurizes the unfixed toner image.

Image heating apparatus with temperature control in relation to glass transition of toner

An image forming apparatus is provided in which on-surface potential unevenness of an image carrier can be suppressed, and with which an output image having excellent on-surface uniformity of color or the like can be obtained. The image forming apparatus includes: a photoconductive image carrier; charger which charges the image carrier; image exposing unit which exposes an image on a surface of the image carrier after the charging to form a latent electrostatic image; developing unit which develops the latent electrostatic image by adhering toner to the latent electrostatic image to form a toner image; and transfer charger which transfers the obtained toner image to a final supporting member such as plain paper.

Image forming apparatus which corrects charge potential on an image carrier

The present invention further improves gradation characteristics from a highlight region to a high-density region. First, the correction processing receives image data, and an image attribute discrimination discriminates whether the data are related to a character/thin line or others on the basis of attribute information on a pixel of interest. If it is discriminated that the data are related to a character/thin line, a pattern matching to data stored in a line buffer is performed to obtain a pixel distance, and in accordance with the pixel distance, a correction amount is determined on the basis of an LUT set in a correction amount determination. Subsequently, on the basis of the determined correction amount, corrected image data are generated and output to the following step.

Semiconductor laser drive control device

An image forming apparatus includes an electrophotographic photoconductive body for forming an electrostatic latent image thereon; an exposure device for exposing the electrophotographic photoconductive body to form an electrostatic latent image; a storage device for storing information related to potential characteristics at a plurality of areas divided on a surface of the electrophotographic photoconductive body in advance; an information obtaining device for obtaining the information related to potential characteristics, wherein light quantities exposed by the exposure device are determined according to the information related to potential characteristics stored by the storage device and the information related to potential characteristics obtained by the information obtaining device.

Image forming apparatus and method featuring correction for compensating differences in surface potential characteristics of an image supporting body

An image forming apparatus includes an image bearing member capable of being rotated, a first charging unit, an electrostatic image forming unit, a developing unit, and a second charging unit. The first charging unit is capable of being rotated in the same direction as a rotational direction of the image bearing member with being in contact with the image bearing member, and is capable of charging the image bearing member and toner on the image bearing member. The electrostatic image forming unit is capable of forming an electrostatic image on the image bearing member charged by the first charging unit. The developing unit is capable of collecting the toner on the image bearing member and visualizing the electrostatic image. The second charging unit is disposed downstream of the first charging unit along the rotational direction of the image bearing member, is capable of being rotated in a direction opposite to the rotational direction of the image bearing member with being in contact with the image bearing member, and is capable of charging the toner on the image bearing member.

Image forming apparatus using system for cleaning image bearing member

When pixels in a two-dimensional matrix are divided into lines A and B in the column (or row) direction (sub-scanning direction) and two neighboring pixels in the row (or column) direction are subjected to gradation correction respectively using characteristic curves for lines A and B, the characteristic curve for line B unpreferably has a stepwise characteristic portion having a step when it is stored in an LUT, due to quantization errors unique to digital values. Hence, the characteristic curve for line A is set to be decreased by the amount corresponding to the step.

Image processing apparatus and method

When maximum density of an output image is lowered by a gamma correction, the number of tones is reduced and the tonality of the output image declines. In order to solve this problem, a pattern generator ( ) is caused to generate a toned pattern and the gain of a D/A converter of a PWM circuit ( ) is controlled so as to output a test pattern having a density ranging from maximum pulse width Pff(50%) to maximum pulse width Pff(100%) for each color component (step S ). Image information that has been read (step S ) from the test pattern is converted to density information (step S ), and Pff is set (step S ) from the relationship between Pff and image density based upon coordinate information provided by the test pattern.

An image forming apparatus that increases the relative resolution of a small image to be output for recording. When the image forming apparatus is used for copying an image of an original document, when the size of an image to be output is not greater than a predetermined size, a CPU controls a resolution switching unit for increasing the resolution to form an image with increased resolution.

Apparatus for forming images, method of controlling the apparatus, and storage medium

An image processing apparatus for performing pulse-width modulation processing based on input image data. A maximum pulse width of a pulse signal, which can be outputted as a modulation signal obtained by the pulse width modulation, is changed in accordance with an image processing mode.

Image information processing apparatus and method

An image forming apparatus forms an image on a medium by using an output device. A pattern signal for forming a predetermined pattern image on the medium is generated, and image forming parameters for the output device are determined on the basis of the density of the pattern image formed on the medium. The determined image forming parameters are transmitted via bidirectional communication to an external computer or other image forming apparatus.

A system which utilizes plural image forming apparatus, equalizes gradation characteristics of images commonly output from such plural image forming apparatus. When the system includes three color copying apparatus, at first a test pattern image based on data from a pattern generator is output from the color copying apparatus. The prepared image is read by the reader of the color copying apparatus, and, based on the read data, the correction data of a table (LUT) are calibrated for obtaining density data for a laser beam. The calibration of the correction data of the color copying apparatus are conducted in a similar manner using, however, the reader of the same copying apparatus for reading the test pattern. It is therefore, rendered possible to exclude the influence of the difference in the reader characteristics on the calibration, and to equalize the gradation characteristics when the copying apparatus are used as printers.

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Susono, Japan

Tetsuya Atsumi