According to one embodiment, a driving apparatus includes a generating unit and a control unit. The generating unit respectively generates a plurality of pieces of driving data for causing each of a plurality of exposure heads to emit light for forming a plurality of element images. The control unit causes light emission start timings of the plurality of exposure heads based upon each of the plurality of pieces of driving data generated by the generating unit to be different between at least one of the exposure heads and other exposure heads.

According to one embodiment, a driving apparatus includes a generating unit and a control unit. The generating unit respectively generates a plurality of pieces of driving data for causing each of a plurality of exposure heads to emit light for forming a plurality of element images. The control unit causes light emission start timings of the plurality of exposure heads based upon each of the plurality of pieces of driving data generated by the generating unit to be different between at least one of the exposure heads and other exposure heads.

An image forming apparatus includes a fixing device having a fixing belt assembly including a heater, a fixing belt, a heater temperature sensor, and a belt temperature sensor, and a pressure roller; a drive current sensor; and a life information acquisition portion. The heater temperature sensor detects the temperature of the heater. The belt temperature sensor detects the temperature of the fixing belt. The pressure roller presses against the fixing belt. The drive current sensor detects a drive current of a drive motor that drives the pressure roller. The life information acquisition portion acquires life information of the fixing belt assembly. A controller selects a failure prediction processing mode based on the detection result of the drive current sensor and selects a driving method based on the detection results of the temperature sensors and the acquisition result of the life information acquisition portion in each mode.

An image forming apparatus includes a fixing device having a fixing belt assembly including a heater, a fixing belt, a heater temperature sensor, and a belt temperature sensor, and a pressure roller; a drive current sensor; and a life information acquisition portion. The heater temperature sensor detects the temperature of the heater. The belt temperature sensor detects the temperature of the fixing belt. The pressure roller presses against the fixing belt. The drive current sensor detects a drive current of a drive motor that drives the pressure roller. The life information acquisition portion acquires life information of the fixing belt assembly. A controller selects a failure prediction processing mode based on the detection result of the drive current sensor and selects a driving method based on the detection results of the temperature sensors and the acquisition result of the life information acquisition portion in each mode.

With this invention, color shifting correction is performed first based on shifting amount information indicating a shifting amount with respect to the scanning direction on an image carrier of each image forming unit, and halftone processing is then performed, thus suppressing generation of moiré due to the color shifting correction, and forming a high-quality image. To this end, an image forming engine has color shifting amount storage units C, M, Y, and K (black) which store actual shifting amounts with respect to ideal scan directions on image carriers C, M, Y, and K in image forming units C, M, Y, and K. Color shifting correction amount arithmetic units C, M, Y, and K calculate color shifting correction amounts for respective color components on the basis of the stored color shifting amounts. Color shifting correction units C, M, Y, and K perform color shifting correction by converting coordinates upon reading out image data from bitmap memories C, M, Y, and K on the basis of the calculated color shifting correction amounts, and then perform tone correction. Data after tone correction undergo halftone processing by halftone processors. C, M, Y, and K. PWM processors C, M, Y, and K generate PWM signals for scanning, and output them to exposure units C, M, Y, and K of the respective image forming units.

With this invention, color shifting correction is performed first based on shifting amount information indicating a shifting amount with respect to the scanning direction on an image carrier of each image forming unit, and halftone processing is then performed, thus suppressing generation of moiré due to the color shifting correction, and forming a high-quality image. To this end, an image forming engine has color shifting amount storage units C, M, Y, and K (black) which store actual shifting amounts with respect to ideal scan directions on image carriers C, M, Y, and K in image forming units C, M, Y, and K. Color shifting correction amount arithmetic units C, M, Y, and K calculate color shifting correction amounts for respective color components on the basis of the stored color shifting amounts. Color shifting correction units C, M, Y, and K perform color shifting correction by converting coordinates upon reading out image data from bitmap memories C, M, Y, and K on the basis of the calculated color shifting correction amounts, and then perform tone correction. Data after tone correction undergo halftone processing by halftone processors. C, M, Y, and K. PWM processors C, M, Y, and K generate PWM signals for scanning, and output them to exposure units C, M, Y, and K of the respective image forming units.

An image forming apparatus that forms an image according to light emitted from a light source is provided. The image forming apparatus includes: a first image processor that performs image processing on image data having a first resolution and outputs the resulting image data; a resolution converter that acquires the image data having the first resolution output from the first image processor and converts the image data to image data having a second resolution that is higher than the first resolution; a modulation signal generator that modulates the image data having the second resolution according to a clock signal to thereby generate a modulation signal; a light source driver that drives the light source according to the modulation signal; and a second image processor that performs image processing on the image data having the second resolution to be modulated to the modulation signal.

An image forming apparatus that forms an image according to light emitted from a light source is provided. The image forming apparatus includes: a first image processor that performs image processing on image data having a first resolution and outputs the resulting image data; a resolution converter that acquires the image data having the first resolution output from the first image processor and converts the image data to image data having a second resolution that is higher than the first resolution; a modulation signal generator that modulates the image data having the second resolution according to a clock signal to thereby generate a modulation signal; a light source driver that drives the light source according to the modulation signal; and a second image processor that performs image processing on the image data having the second resolution to be modulated to the modulation signal.

A conveyance device includes a conveyance roller pair to convey a recording medium to an image reading position of an image reading unit. The conveyance roller pair includes a drive roller and a driven roller. The driven roller contacts the drive roller and rotates following the drive roller. The drive roller has a diameter satisfying a relation in which a detection mark on the recording medium is on a position away from a leading end of the recording medium by an integral multiple of a circumference of the drive roller in a conveyance direction of the recording medium.

A conveyance device includes a conveyance roller pair to convey a recording medium to an image reading position of an image reading unit. The conveyance roller pair includes a drive roller and a driven roller. The driven roller contacts the drive roller and rotates following the drive roller. The drive roller has a diameter satisfying a relation in which a detection mark on the recording medium is on a position away from a leading end of the recording medium by an integral multiple of a circumference of the drive roller in a conveyance direction of the recording medium.