A method of operating a printing system includes determining whether ghosting is expected on a photoreceptor and applying power to a laser applied to the photoreceptor based on whether the ghosting is expected.

A sheet sorting device according to an embodiment includes a transporting unit that transports a sheet. A reading unit generates an image of a surface of the sheet. A decoloring unit performs a decoloring processing to decolor an image on the sheet. The sheet sorting device includes a plurality of sheet stacking trays. A processor causes the reading unit to generate an image of the surface of the sheet after the decoloring unit performs the decoloring processing on the sheet. The processor determines a color of the sheet based on the generated image. The processor determines one sheet stacking tray out of the plurality of sheet stacking trays as a transport destination of the sheet, based on the determined color. The transporting unit transports the sheet to the determined sheet stacking tray.

According to an embodiment, an image processing apparatus includes a detector, a heater, and a controller. The detector detects an image formed on a sheet. The heater applies a predetermined heat amount onto the sheet to carry out erasing processing on the sheet. The controller controls, based on a detection result of the detector, the number of times the erasing processing is to be carried out on the sheet and a heat amount to be applied onto the sheet in the erasing processing.

A post-processing apparatus includes a post processer, a conveyor, a surface detector, an air blower, and a switch. The post processer performs post processing on a medium. The conveyor conveys the medium. The surface detector detects a surface of the medium. The air blower blows air toward the surface of the medium. The air blower includes an air blowing fan, multiple air blower ports, and an air duct. The air blowing fan generates airflow. The multiple air blower ports blow air to the medium. The air duct couples the air blowing fan and the multiple air blower ports to guide the air from the air blowing fan to each of the air blower ports. The switch controls the amount of the air blown from each of the multiple air blower ports to the medium based on a detection of the surface of the medium by the surface detector.

This image forming apparatus includes: a plurality of sheet accommodating portions each including a sheet placement portion on which a sheet is placed; a lifting/lowering portion configured to lift and lower the sheet placement portion; an image forming portion configured to form an image on the sheet supplied from each sheet accommodating portion; and an engine control portion configured to control the image forming portion on the basis of inputted print data. The engine control portion causes the lifting/lowering portion to lift the sheet placement portion to a predetermined sheet feed possible position in response to reception of the type of the sheet, and after the image formation by the image forming portion is finished, the engine control portion causes the lifting/lowering portion to lower the sheet placement portion to a predetermined original position.

A method of operating a printing system includes determining whether ghosting is expected on a photoreceptor and applying power to a laser applied to the photoreceptor based on whether the ghosting is expected.

The image forming apparatus transfers an image onto a surface of a sheet at a transfer position on a conveying path. A pair of conveying rollers convey the sheet to the transfer position. The image sensor reads the sheet upstream of the transfer position. The rotary body is disposed to face the image sensor with the conveying path interposed therebetween. The rotary body includes a background portion configured to face a reading surface of the image sensor when the rotary body is at a first rotational position, and a cleaning portion configured to come into contact with the reading surface of the image sensor when the rotary body is at a second rotational position.

An image forming apparatus includes: an image forming unit that transfers a toner image onto a recording medium, the toner image being formed on an image carrier by an electrophotographic system; and one or more processors that control an operation of the image forming unit, and that are configured to: perform multiple operations under different conditions about charging and exposure to light in predetermined order, the operations including at least an operation of forming a toner image on the recording medium with the image carrier having been subjected to charging and exposure to light and an operation of forming a toner image on the recording medium with the image carrier having been subjected to no exposure to light and optionally to charging; and control the image forming unit to form margins of different forms, the margins being formed on pieces of the recording medium in the respective operations performed under the different conditions.

An image forming apparatus includes an image forming unit configured to form an image on a sheet, a reversing unit configured to convey a sheet conveyed from the image forming unit in a first direction, stop the conveyance, and then convey the sheet in a second direction, which is opposite to the first direction, an image detection unit disposed to detect at least a portion of the image on the sheet stopped by the reversing unit, and a control unit configured to control the reversing unit and the image detection unit. The control unit is configured to detect the image on the sheet by the image detection unit while the sheet conveyance is stopped by the reversing unit.

An image formation apparatus includes: an image former that prints an image on paper; a corrector that corrects a print position of the image on the paper; and a first sensor that is disposed on a conveyance path upstream of the image former, detects paper, and outputs detection data to the corrector, wherein the corrector obtains, on the basis of the detection data, an amount of change in a shape of first paper from a shape of second paper printed before the first paper is printed, and corrects a print position of a first image on the first paper on the basis of the change amount.