Abstract: A processor derives a plurality of unit density values which are each an average value of sensed densities for each of a plurality of unit areas sectioned for each unit length in a test toner image. The processor derives a weighted average of the plurality of unit density values to derive a test image density used for adjusting a control parameter in a printing portion. The unit length is a greatest common factor of two target lengths corresponding to perimeters of two types of target rotating members out of the plurality of rotating members. When a number of the plurality of unit areas is represented by n, n is a value obtained by subtracting 1 from an added value of a first constant and a second constant. The first constant and the second constant are values obtained by respectively dividing the two target lengths by the unit length.

Abstract: A light-source-driving control device thins a pixel at an edge portion of image data by a first pixel width; sets a second pixel width at the edge portion such that a ratio between the first and second pixel widths is constant; creates light amount information including a first light amount with which a pixel not included in the set second pixel width is exposed, and a second light amount with which a pixel included in the second pixel width is exposed; selects the first or second light amount based on a power-modulation control signal; drives light sources according to the selected light amount and a light-source-modulation pulse signal; and counts an addition value of pixel density considering a pixel width and a light amount, based on a data-width setting signal based on the second pixel width, and on a light-amount setting signal based on the light amount information.

Abstract: An image forming apparatus for forming an image in accordance with light to be emitted from a light source includes: a digital half-toning unit configured to convert a uniform-pixel-value region of image data to a parallel-line pattern formed with a plurality of parallel lines extending obliquely with respect to a direction, in which pixels are arrayed, thereby expressing each gray level of the image data as an area percentage; a modulated-signal generating unit configured to generate a modulated signal by modulating the converted image data with a clock signal; a light-source driving unit configured to drive the light source according to the modulated signal; and an edge control unit configured to narrow a to-be-illuminated region, which is to be illuminated by the light from the light source, in each of edge neighborhoods of the lines constituting the parallel-line pattern, while increasing intensity of the light.

Abstract: An image processing apparatus includes an image-processing designating unit that allows a user to designate predetermined image processing to be applied to image data for generating a preview image that represents a state of an output image before image output; a preview-image generating unit that generates a preview image in accordance with the designated image processing; a preview-image display unit that displays the preview image generated by the preview-image generating unit; and a display-mode switching control unit that, when the preview image is displayed, switches to a display mode with an enhanced viewability relative to a power-saving display state in accordance with a content of the designated image processing.

Abstract: The present invention provides an illuminating device including a plurality of light-emitting elements arranged in a line, the illuminating device illuminates an irradiation target by irradiating the irradiation target with light that is emitted from the light-emitting elements via a first and a second optical paths. In the illuminating device, a light diffusing portion for diffusing light is provided in one of the first optical path and the second optical path, and an irradiation light amount of said one of the first optical path and the second optical path in which the light diffusing portion is provided is larger than an irradiation light amount of the other optical path.

Abstract: There are provided an image reader with high resolution capability for images in a high density range and an image forming apparatus. An image reader 2 comprises a reflected light reading unit (11, 12, 13, 14, 10) for irradiating a surface to be read of an original sheet with a light and reading the amount of the reflected light and a transmitted light reading unit (15, 12, 13, 14, 10) for irradiating the original sheet with a light and reading the amount of the transmitted light, and calculates the density of an image of the original sheet based on the amount of the reflected light read by the reflected light reading unit and the amount of the transmitted light read by the transmitted light reading unit.

Abstract: A color image forming apparatus for forming toner images by carrying out charging, exposure, and development on at least one photoreceptor drum, and forming color images by transferring the toner images onto sheets, the color image forming apparatus including: a photoreceptor drum which rotates around an axis; an exposure section which intermittently emits a light beam onto the cylindrical surface of the rotating photoreceptor drum along scanning lines parallel to the axis of the photoreceptor drum; a calculation section which calculates a printing ratio of a color image to be formed on one sheet, wherein the printing ratio is the ratio of the area covered by toner in the color image; and a timing control section which controls a timing when the exposure section emits the light beam in a direction of rotation of the photoreceptor drum based on the printing ratio calculated by the calculation section.

Abstract: In a color misalignment detection method, an alignment pattern is obtained by designating a plurality of lines having line width and line intervals formed by superposing a line image of a black color as a reference color and a line image of a color other than the reference color, for example, a cyan line image, as one patch, and continuously forming these patches by shifting the relative position between the line images of the two colors by an optional quantity. An alignment pattern detection sensor has a light emitting diode and a photodiode. These elements are arranged along the scanning direction of the alignment pattern such that the photodiode can only receive diffused reflected light of reflected light from the alignment pattern. A spot shape of the light emitting diode and a spot shape of the photodiode are both formed in a square shape.

Abstract: A correction method for correcting unintended spatial variation in lightness across a physical image produced by a xerographic process, the method comprising producing a test image using the xerographic process, measuring a difference between actual lightness and intended lightness across at least part of the test image, and varying the light source level used subsequently in the xerographic process to correct for the measured unintended difference.

Abstract: When the density of a toner image of a leading end of a printing sheet is no less than a predetermined reference density, a printing start time is delayed or printing data is deleted so that printing data is not printed in the leading end of the sheet. When the printing is performed in a state where a cover used for copying is opened, a printing start time is delayed or the printing data of the leading end of the printing sheet is deleted. Therefore, it is possible to prevent a fixing unit from being contaminated due to the toner image transferred to the leading end of the printing sheet.

Abstract: A deviation amount detecting device for use in an electrophotographic color image forming device is configured to correct, during an inter-cycle period in which computation of a first deviation amount using a result of reading of deviation detection patterns is held in a waiting state, a second deviation amount computed using a result of measurement of a scanning time of a light beam, based on a first deviation amount computed at a latest cycle, so that a corrected amount of deviation of a main scanning direction and a corrected amount of deviation of a sub-scanning direction are computed.

Abstract: In a disclosed image forming apparatus, a developing bias applied to a developer carrier or exposure energy with which an image carrier is exposed is adjusted such that an isolated one-dot image on the image carrier has a predetermined image density. When the image carrier is exposed to form dot images continuously arranged in a sub scanning direction, the exposure time period for each dot image is shorter than a time period for exposing the image carrier to form the isolated one-dot image.

Abstract: In an image forming apparatus, an exposure device performs exposure on a non-image area of image pattern, performs an exposure on the image area in an exposure amount lower than the non-image area or does not perform exposure, and an exposure amount control device controls, with respect to pixels having the same density data, an exposure amount given by an exposure device to be smaller in a first portion, which is a thin-line of a width that is equal to or less than a predetermined number of pixels or which is an isolated dot of widths that are equal to or less than the predetermined number of pixels in two directions substantially orthogonal to each other, than in a second portion which is a line of a width exceeding the predetermined number or a surface of widths that exceed the predetermined number in two directions substantially orthogonal to each other.

Abstract: An exposure device includes a light emitting element; and an eccentric cam for adjusting a distance between the light emitting element and a light receiving member. The eccentric cam includes a shaft portion and a cam portion arranged eccentrically relative to the shaft portion. The cam portion includes a circumferential surface having a convex surface in an axial direction of the eccentric cam and a circular arc in a direction perpendicular to the axial direction.

Abstract: An image forming apparatus which is capable of decreasing the failure rate by improving a photocatalytic material and utilization efficiency thereof, and by decomposing substances that cannot be completely removed with a cleaning member or by not causing the substances to adhere. A light emitting unit irradiates an object to be irradiated with light. A light receiving unit receives reflected light from the irradiated object. A protection sheet containing a photocatalytic material is disposed so as to cover the light emitting unit and light receiving unit. The light emitting unit emits light of a wavelength range adapted to a bandgap width of the protection sheet, and the light receiving unit has sensitivity in a wavelength range of light emitted from the light emitting unit.

Abstract: One embodiment of the present invention can include an image forming apparatus having an image carrier, a light emitting portion capable of emitting a light towards a predetermined position, a light receiving portion capable of detecting a light amount of incident light from the predetermined position, a light emission control portion capable of changing an outgoing light amount of the light emitting portion, and a determining portion capable of determining whether or not the image carrier is disposed in the predetermined position based on a change in detected light amounts at the light receiving portion including a change in the outgoing light amount of the light emitting portion.

Abstract: An image forming apparatus, which includes: an image forming section to form an image on a transfer sheet conveyed to the image forming section; an edge detecting sensor which detects an edge position of the transfer sheet in a main scanning direction while the transfer sheet is conveyed to the image forming section; and a controller which controls an image writing position at the image forming section based on a result of an edge position detection by the edge detecting sensor; wherein the edge detecting sensor comprises a plurality of light sources each having a different wavelength, and the controller comprises a light source controller which controls lighting of the plural light sources.

Abstract: The invention relates to a method for operating an electrophotographic printing device (10). A multilevel character generator (22) is used in said printing device (10). Correction parameters (K1, K2, K3) are determined for light coding values (1, 2 and 3) such that a high-quality printed image can he obtained also in the instance of modified printing conditions.

Abstract: There is disclosed a rubber composition comprising (A) butadiene rubber and/or (B) isoprene rubber in the form of liquid and (C) silicone rubber at a {(A)+(B)}/(C) ratio by weight in the range of 97/3 to 5/95. The composition is capable of affording an elastic member which has a low hardness and excellent wear resistance, and which is well suited for use in a variety of part items that are installed in an image formation apparatus such as an electrophotographic apparatus and an electrostatic recording apparatus, including copying machinery, printers, facsimile apparatus and the like, in particular a developing roller. There are also disclosed a developing roller which comprises the above rubber composition, is improved in wear resistance for a developer without causing high hardness thereof, and is capable of affording a steadily favorable image without fail for a long period of time; and further a developing apparatus which comprises the above developing roller.

Abstract: An image reading apparatus including a backing member arranged on the original transport path, a light source for emitting the light toward the original reading position in the original transport path in the direction of a predetermined incident optical axis, a detector capable of detecting the light reflected at the original reading position in the direction of a predetermined reading optical axis, and an image processing apparatus. The reflection surface of the backing member is configured in such a manner that the amount of the light reflected by the backing member and detected by the detector is not less than the amount of the light corresponding to a white reference value and that the amount of the light passing through the original, reflected by the backing member, re-passing through the original and detected by the detector, is not more than the amount of the light capable of preventing the imaging from the reverse side.

Abstract: An electrostatographic reproduction method and apparatus includes an electrostatic recording member moving in a process direction. A plurality of recording elements on a writer imagewise expose the recording member to form electrostatic latent images on the recording member. The writer includes driver circuitry for actuating selected recording elements. The exposed recording member is then moved through a development station to develop the latent images. The developed images are transferred to a record member. An operator selectable adjustment controller is manually adjusted for generating adjustments in operation of the recording elements to compensate for a misalignment of a process station in the apparatus.

Abstract: In the tri-level process in which positive and negative latent images are formed on a photosensitive body and then developed using toners of two colors (for example, red and black) charged respectively to opposite polarities with respect to the polarities of the latent images, there has been a problem of degrading the quality of a two-color picture by the appearance of a special phenomenon in which red toner is attached around a black image and black toner is attached around a red image by attraction of the reverse electric field. An exposure control is performed in order to suppress the fringe phenomenon.

Abstract: A video signal recording and reproduction apparatus, provided with at least one encoding apparatus for encoding an input video signal, at least one data storage apparatus for recording and reproducing a video signal encoded by the encoding apparatus, a line switching apparatus for selectively connecting the encoding apparatus and data storage apparatus or selectively connecting the data storage apparatus and an output line of the video signal; and a control apparatus for controlling the line switching apparatus and the data storage apparatus in accordance with a recording command or reproduction command.

Abstract: The invention provides an image forming apparatus which requires only a little standby time at the time of shifting from a standby state to a usual operation state, and accordingly can reduce the required processing time. In a copy machine 2 employed in the invention, a scanner CPU 121 generates a timing signal with a number of clocks substantially equal to the number of clocks of a horizontal synchronization signal, thereby performing shading correction of the output of a CCD line sensor 24 using a shading correction circuit 126. The scanner CPU 121 counts clocks CKS, each of which is obtained by dividing, using the divider 168, the frequency of a reference clock CK by a predetermined value, and outputs a pulse signal as the timing signal substantially in synchronism with the output of a horizontal synchronization signal when the number of counted clocks CKS reaches a predetermined value.

Abstract: This invention concerns an automatic exposure adjusting apparatus which permits infallible production of a signal corresponding exactly to the density of a given original document constantly even when the components of an optical system thereof cause any dispersion or gradual deterioration due to aging. First, the apparatus exposes a standard white subject copy 1 set on a document table 2 to the light of a preset standard amount of exposure, samples the reflected light from the copy 1 by a light detector 14, and adjusts to a proper magnitude the output value of an original document density signal emitted from a noninverting amplifier 33. Then, it exposes the standard density plate 3 to the light of an adjusted standard amount of exposure, samples the reflected light from the standard density plate 3 by the light detector 14, and readjusts to a proper magnitude the output value of an original document density signal issued from the noninverting amplifier 33.

Abstract: An original density detecting apparatus includes a projector-receiver including a light projector and a light receiver, and a reflecting member including a fluorescent reflecting plate a surface of which on the projector-receiver side is a coating of a fluorescent dye. An image forming apparatus includes an illuminating device for illuminating an original, an image reader for forming an image of the original on a photosensitive medium, and the original density detecting apparatus as described above.

Abstract: In order to effectively perform image stabilization by control of retaining initial characteristics of a photosensitive body, if correlation between initial and aged values corresponding to bright and dark part signals of the photosensitive body is such that a variation between the initial and aged values of the dark part signal (dark .DELTA.) is greater than a variation between the initial and aged values of the bright part signal (bright .DELTA.), an image stabilizer, first, controls a charging characteristic of the aged values by changing a charging output to the photosensitive body so that the bright .DELTA. and the dark .DELTA. are equal to each other. Next, the image stabilizer makes the aged characteristics of the photosensitive body virtually identical to the initial characteristics by changing an exposure output so that the aged and initial values of the dark part signal become equal to each other.

Abstract: The current invention discloses photocopying methods and systems for substantially eliminating shadows caused by uneven surfaces of an original by the use of a light diffusing element or a carrier sheet which automatically triggers the associated photocopying parameters. The light diffusing element has a marker or an identification code which is detected by a sensor placed along a paper path, and the marker contains various type of information used for adjusting the photocopying conditions associated with the use of the light diffusing element. The light diffusing element is also designed to be used with an automatic document feeder.

Abstract: In an adjustment mode, a black reference member is positioned opposite to a photosensor. Light reception data output from an A/D converter at this time is stored in a memory. In an image formation mode, based on a value obtained by subtracting output data stored in the memory from output data of the A/D converter in a state where the photosensor is opposite to an original, a copy lamp is driven. As a result, an image mode can be controlled based on an accurate detection result of an image density.