Abstract: Adjustment of white balance based on a measurement result of light emission luminance of a backlight is allowed to be executed accurately and effectively. A backlight luminance detection portion detects light emission luminance of an LED backlight in a state where an optical shutter of a liquid crystal display panel is closed. A main control portion adjusts light emission luminance of the LED backlight according to light emission luminance detected by the backlight luminance detection portion. Here, the main control portion compares light emission luminance of LEDs of RGB detected by the backlight luminance detection portion with light emission luminance of RGB in white balance adjustment that is stored in advance in the storage portion, and adjusts, when an error occurs between the compared light emission luminance, the light emission luminance of each of the LEDs of RGB so as to eliminate the error.

Abstract: An illumination device includes a light source in which a plurality of light emitting elements are arranged, a luminous intensity controller configured to control luminous intensities of the plurality of light emitting elements separately in groups of one or more light emitting elements, and a predetermined correction table indicating temperature distribution characteristics corresponding to position information of the plurality of light emitting elements in the light source. The luminous intensity controller controls the luminous intensities of the plurality of light emitting elements corresponding to the position information based on the temperature distribution characteristics of the correction table.

Abstract: A document reader includes an image sensor. The image sensor is movable in a secondary scanning direction and rotatable about a rotational axis extending in a primary scanning direction, and obtains image information from a region facing a light-receiving surface. Rotation of the image sensor is controlled based on distance information about a distance between a document surface and a platen in such a manner as to make an image distance fall within a depth-of-field range of the image sensor.

Abstract: An illumination device includes a light source in which a plurality of light emitting elements are arranged, a luminous intensity controller configured to control luminous intensities of the plurality of light emitting elements separately in groups of one or more light emitting elements, and a predetermined correction table indicating temperature distribution characteristics corresponding to position information of the plurality of light emitting elements in the light source. The luminous intensity controller controls the luminous intensities of the plurality of light emitting elements corresponding to the position information based on the temperature distribution characteristics of the correction table.

Abstract: A pair of registration rollers are provided upstream in a paper transport path from an image forming position, and a paper transport position detection portion is provided upstream in the paper transport path from the pair of registration rollers. When consecutive print processing on a plurality of sheets of paper is performed, a paper transport position in the paper transport path is detected by the paper transport position detection portion for a sheet of paper that has been set in advance among the plurality of sheets of paper. A correction amount of a position for image writing to a photosensitive drum is determined based on the paper transport position, and correction of the image writing position is performed based on the correction amount.

Abstract: An image forming apparatus includes at least one paper feeding section, a plurality of image forming sections, a plurality of paper output sections, a main transport path, and a plurality of paper output paths. The paper feeding section stores a recording medium therein. Any one of the image forming sections selectively forms an image on a recording medium fed from the paper feeding section and being transported on the main transport path. Each of the paper output sections receives a recording medium bearing an image formed in any one of the image forming sections. The main transport path leads from the paper feeding section and runs through the image forming sections. The paper output paths branch from an end of the main transport path into the respective paper output sections.

Abstract: The present invention provides a sheet feeding apparatus including an overlapped feeding detection apparatus which can securely detect overlapped feeding as to a sheet being fed, and a document feeding apparatus and an image processing apparatus including the sheet feeding apparatus. A paper feeding apparatus 1b includes a paper feed tray 11, a pickup roller 61, a paper roller 63, a sorting roller 64, feeding rollers 66a, resist rollers 67, a paper ejection roller 73, a passage detection sensor 69, an overlapped feeding detection sensor 68 and a second detection apparatus 71. Recording paper is delivered from the paper feed tray 11 by the pickup roller 61 according to a printing instruction from a user. The recording paper is fed to the resist rollers 67 through the paper roller 63, the sorting roller 64, the feeding rollers 66a and the passage detection sensor 69. The recording paper temporarily stops at the resist rollers 67.

Abstract: The image forming apparatus of the present invention includes a first and a second main conveyance path, a first and a second processing unit, a transfer unit, and a fixing unit. The first and second main conveyance paths come together after having branched apart between a paper supply unit and a paper delivery unit. A recording medium is selectively conveyed along either one of the first and second main conveyance path. Image formation is performed by a method of electrophotography by, alternatively, either the first or second processing unit. Between the first and second main conveyance paths where they are branched apart, the transfer unit generates a transfer electric field between itself and one or the other of the first and second processing unit. The fixing unit controls the temperature of a first or a second fixing roller, which are disposed in the first and second main conveyance path after they have come together, alternatively.

Abstract: A document reader includes an image sensor. The image sensor is movable in a secondary scanning direction and rotatable about a rotational axis extending in a primary scanning direction, and obtains image information from a region facing a light-receiving surface. Rotation of the image sensor is controlled based on distance information about a distance between a document surface and a platen in such a manner as to make an image distance fall within a depth-of-field range of the image sensor.

Abstract: A paper multi-feed detection apparatus and a paper multi-feed detection method are provided for preventing the detection capability from being deteriorated by a noise factor and improving the detection precision even where an area around the feeding path has no extra space in terms of the shape and there are many noise-generating factors because of a demand for a smaller size of the device. An ultrasonic transmission opening formed in one of two feeding guide plates is large so as to discharge outside a reflected wave which returns through the ultrasonic transmission opening, and an ultrasonic receiving opening formed in the other feeding guide plate is smaller than a receiving face area of a receiver for receiving the ultrasonic wave.

Abstract: The present invention provides a sheet feeding apparatus including an overlapped feeding detection apparatus which can securely detect overlapped feeding as to a sheet being fed, and a document feeding apparatus and an image processing apparatus including the sheet feeding apparatus. A paper feeding apparatus 1b includes a paper feed tray 11, a pickup roller 61, a paper roller 63, a sorting roller 64, feeding rollers 66a, resist rollers 67, a paper ejection roller 73, a passage detection sensor 69, an overlapped feeding detection sensor 68 and a second detection apparatus 71. Recording paper is delivered from the paper feed tray 11 by the pickup roller 61 according to a printing instruction from a user. The recording paper is fed to the resist rollers 67 through the paper roller 63, the sorting roller 64, the feeding rollers 66a and the passage detection sensor 69. The recording paper temporarily stops at the resist rollers 67.

Abstract: A pair of registration rollers are provided upstream in a paper transport path from an image forming position, and a paper transport position detection portion is provided upstream in the paper transport path from the pair of registration rollers. When consecutive print processing on a plurality of sheets of paper is performed, a paper transport position in the paper transport path is detected by the paper transport position detection portion for a sheet of paper that has been set in advance among the plurality of sheets of paper. A correction amount of a position for image writing to a photosensitive drum is determined based on the paper transport position, and correction of the image writing position is performed based on the correction amount.

Abstract: An image forming apparatus includes at least one paper feeding section, a plurality of image forming sections, a plurality of paper output sections, a main transport path, and a plurality of paper output paths. The paper feeding section stores a recording medium therein. Any one of the image forming sections selectively forms an image on a recording medium fed from the paper feeding section and being transported on the main transport path. Each of the paper output sections receives a recording medium bearing an image formed in any one of the image forming sections. The main transport path leads from the paper feeding section and runs through the image forming sections. The paper output paths branch from an end of the main transport path into the respective paper output sections.

Abstract: The image forming apparatus of the present invention includes a first and a second main conveyance path, a first and a second processing unit, a transfer unit, and a fixing unit. The first and second main conveyance paths come together after having branched apart between a paper supply unit and a paper delivery unit. A recording medium is selectively conveyed along either one of the first and second main conveyance path. Image formation is performed by a method of electrophotography by, alternatively, either the first or second processing unit. Between the first and second main conveyance paths where they are branched apart, the transfer unit generates a transfer electric field between itself and one or the other of the first and second processing unit. The fixing unit controls the temperature of a first or a second fixing roller, which are disposed in the first and second main conveyance path after they have come together, alternatively.