Abstract: An image forming apparatus includes a control unit that generates a valid region signal corresponding to the length of a paper sheet of a regular size in the conveyance direction thereof, and performs control to form an image on the paper sheet based on the valid region signal, wherein, when an image is formed on a long paper sheet having a longer length than the paper sheet of the regular size, the control unit generates the valid region signal in each channel, performs control for generating the next valid region signal in a period during which the valid region signal is not generated in any of the channels, generates a continuous valid region signal corresponding to the long paper sheet by combining the valid region signals in the channels, and performs control to form an image by reading out image data based on the continuous valid region signal.

Abstract: An image forming apparatus includes a control unit that generates a valid region signal corresponding to the length of a paper sheet of a regular size in the conveyance direction thereof, and performs control to form an image on the paper sheet based on the valid region signal, wherein, when an image is formed on a long paper sheet having a longer length than the paper sheet of the regular size, the control unit generates the valid region signal in each channel, performs control for generating the next valid region signal in a period during which the valid region signal is not generated in any of the channels, generates a continuous valid region signal corresponding to the long paper sheet by combining the valid region signals in the channels, and performs control to form an image by reading out image data based on the continuous valid region signal.

Abstract: Disclosed is an image forming apparatus includes: an image forming section, a control section, and a magnification factor adjusting section. The control section employs an index signal based on a detected result of a light beam irradiation, for controlling an operation timing of the image forming section in the toner image area; and when forming the band-shaped toner image on the area between the toner image areas being adjacent to each other, while controlling the magnification factor adjusting section to implement an operation for adjusting the image magnification factors in parallel, the control section employs a timing signal, created otherwise without depending on the detected result of the light beam irradiation, for controlling the operation timing of the image forming section.

Abstract: Disclosed is an image forming apparatus includes: an image forming section, a control section, and a magnification factor adjusting section. The control section employs an index signal based on a detected result of a light beam irradiation, for controlling an operation timing of the image forming section in the toner image area; and when forming the band-shaped toner image on the area between the toner image areas being adjacent to each other, while controlling the magnification factor adjusting section to implement an operation for adjusting the image magnification factors in parallel, the control section employs a timing signal, created otherwise without depending on the detected result of the light beam irradiation, for controlling the operation timing of the image forming section.

Abstract: An image forming apparatus including a control section which detects an offset of a recording sheet being conveyed, the offset being in a main scanning direction perpendicular to a conveyance direction of the recording sheet; performs an offset regulation control which adjusts a main scanning direction image area signal in accordance with the offset; and forms a patch at a non-transfer area on an image carrier, wherein the control section performs a first control based on the offset of the recording sheet for the offset regulation control while a sub scanning direction image area signal is active for image forming on the recording sheet, and performs a second control for the offset regulation control while the image area signal in the sub scanning direction is inactive.

Abstract: An image forming apparatus including a control section which detects an offset of a recording sheet being conveyed, the offset being in a main scanning direction perpendicular to a conveyance direction of the recording sheet; performs an offset regulation control which adjusts a main scanning direction image area signal in accordance with the offset; and forms a patch at a non-transfer area on an image carrier, wherein the control section performs a first control based on the offset of the recording sheet for the offset regulation control while a sub scanning direction image area signal is active for image forming on the recording sheet, and performs a second control for the offset regulation control while the image area signal in the sub scanning direction is inactive.

Abstract: This invention is directed to an image printing apparatus which can print images without any halfway offset or obverse/reverse pixel offset at a low cost. An image printing apparatus includes a clock generating section which generates a dot clock as the basis of each pixel forming an image, an image printing section which prints a one-line image in a main scanning direction in accordance with image data with reference to the dot clock output from the clock generating section, and prints a one-page image by repeating in the sub-scanning direction one-line image printing performed in the main scanning direction, and a clock control section which changeably controls the frequency of the dot clock during scanning of one line in the main scanning direction.

Abstract: A tandem type color image forming apparatus, which can continuously form color images each containing two or more colors, including: a signal creating section having, for each color, two or more image area setting counters for generating an image valid area signal to set a starting position and a width of an image formation area in a sub-scanning direction; and a control section for executing color image formation control on a predetermined face of paper, based on an image top signal for controlling writing of an image on an image carrier and the image valid area signal for each color, wherein the control section sets each of the outputs of the image area setting counters independently according to a preset image formation mode, and selects and controls one of the image area setting counters for each image formation of each color.

Abstract: An image forming apparatus including a control section which detects an offset of a recording sheet being conveyed, the offset being in a main scanning direction perpendicular to a conveyance direction of the recording sheet; performs an offset regulation control which adjusts a main scanning direction image area signal in accordance with the offset; and forms a patch at a non-transfer area on an image carrier, wherein the control section performs a first control based on the offset of the recording sheet for the offset regulation control while a sub scanning direction image area signal is active for image forming on the recording sheet, and performs a second control for the offset regulation control while the image area signal in the sub scanning direction is inactive.

Abstract: An image forming apparatus which concurrently exposes by multiple laser beams corresponding to M lines on the photoreceptor, comprising: multiple light sources for emitting laser beams; a memory section for storing the image data; a control section to control the plurality of light sources, wherein the control section is capable of controlling image formation by: a first mode for reading-out of image data for M lines, exposing by multiple light sources of M lines according to the image data for M lines, and forming an image at a predetermined sub-scanning direction image formation speed of VM; and a second mode for reading-out of image data for N lines (where N<M), exposing by multiple light sources of M lines according to read-out image data for N lines and blank data for M?N lines, and forming an image at a sub-scanning direction image formation speed VN, where VN=VM?(N/M).

Abstract: This invention relates to a CCD pulse generator capable of generating a CCD driving signal and CCD output processing signal at accurate timings.

Abstract: This invention is directed to an image printing apparatus which can print images without any halfway offset or obverse/reverse pixel offset at a low cost. An image printing apparatus includes a clock generating section which generates a dot clock as the basis of each pixel forming an image, an image printing section which prints a one-line image in a main scanning direction in accordance with image data with reference to the dot clock output from the clock generating section, and prints a one-page image by repeating in the sub-scanning direction one-line image printing performed in the main scanning direction, and a clock control section which changeably controls the frequency of the dot clock during scanning of one line in the main scanning direction.

Abstract: This invention is directed to an image printing apparatus which can print images without any halfway offset or obverse/reverse pixel offset at a low cost. An image printing apparatus includes a clock generating section which generates a dot clock as the basis of each pixel forming an image, an image printing section which prints a one-line image in a main scanning direction in accordance with image data with reference to the dot clock output from the clock generating section, and prints a one-page image by repeating in the sub-scanning direction one-line image printing performed in the main scanning direction, and a clock control section which changeably controls the frequency of the dot clock during scanning of one line in the main scanning direction.

Abstract: A laser scanning apparatus includes: a plurality of laser light sources including a first laser light source and a second laser light source; a scanner for scanning laser lights emitted from the plurality of laser light sources in a main scanning direction; a light receiving sensor for receiving the laser lights deflected and scanned by the scanner; and a signal generation unit for generating a first signal which is in synchronization with a pixel clock for the second laser light source based on an output from the light receiving sensor obtained by a laser light emitted from the first laser light source, and for generating a second signal which is in synchronization with a pixel clock for the first laser light source based on an output from the light receiving sensor obtained by a laser light emitted from the second laser light source.

Abstract: A laser scanning apparatus includes: a plurality of laser light sources including a first laser light source and a second laser light source; a scanner for scanning laser lights emitted from the plurality of laser light sources in a main scanning direction; a light receiving sensor for receiving the laser lights deflected and scanned by the scanner; and a signal generation unit for generating a first signal which is in synchronization with a pixel clock for the second laser light source based on an output from the light receiving sensor obtained by a laser light emitted from the first laser light source, and for generating a second signal which is in synchronization with a pixel clock for the first laser light source based on an output from the light receiving sensor obtained by a laser light emitted from the second laser light source.

Abstract: There is described a signal controlling circuit particularly used in a printer or copier. The circuit includes a delay chain section to generate a plurality of delayed clock signals, a synchronized signal detecting section to detect a number of delay stages, a total delay time of which is equivalent to a single period of the reference clock signal, based on delayed clock signals synchronized with an index signal and are selected from the plurality of delayed clock signals, an index signal counting section to count index signals inputted into the index signal counting section, a phase shift calculating section to calculate a phase shift amount in respect to the reference clock signal, and a delayed clock selecting section to select a specific delayed clock signal out of the plurality of delayed clock signals in an alternative way, so as to output the specific delayed clock signal to an external section.

Abstract: A tandem type color image forming apparatus, which can continuously form color images each containing two or more colors, including: a signal creating section having, for each color, two or more image area setting counters for generating an image valid area signal to set a starting position and a width of an image formation area in a sub-scanning direction; and a control section for executing color image formation control on a predetermined face of paper, based on an image top signal for controlling writing of an image on an image carrier and the image valid area signal for each color, wherein the control section sets each of the outputs of the image area setting counters independently according to a preset image formation mode, and selects and controls one of the image area setting counters for each image formation of each color.

Abstract: The invention concerns a clock-generating circuit, which generates dot clock pulses for driving a light-emitting element employed in an optical-writing section of an image-forming apparatus and has a function of canceling f&thgr; property errors caused by a f&thgr; lens employed in the image-forming apparatus. The clock-generating circuit includes a digital-delay dot clock adjusting section to adjust timings of rising-edges or falling-edges of the dot clock pulses generated by changing a selection for a plurality of delayed-clock pulses, which are generated by delaying clock-pulses, outputted from a reference oscillator, in slightly different delay times; and a controlling section to control a selecting operation for the plurality of delayed clock pulses, performed in the digital-delay dot clock adjusting section, so as to compensate for f&thgr; property errors caused by the f&thgr; lens employed in the optical-writing section.

Abstract: The invention concerns a clock-generating circuit, which generates dot clock pulses for driving a light-emitting element employed in an optical-writing section of an image-forming apparatus and has a function of canceling unevenness of scanning-light amount caused by variations of transmittances and reflectances in the optical-writing section when a polygon mirror scans a laser beam.

Abstract: This invention relates to a CCD pulse generator capable of generating a CCD driving signal and CCD output processing signal at accurate timings.