Abstract: A colorimetric device includes: a feeding unit configured to feed a transfer medium; a colorimeter configured to perform colorimetry of an image that is formed on the transfer medium and that has a color boundary in a feeding direction; and a colorimetry control unit configured to control the feeding unit and the colorimeter, wherein the colorimetry control unit acquires color information related to the color boundary of the image and determines the color boundary of the image based on the color information and a result of the colorimetry performed by the colorimeter.

Abstract: An image forming apparatus includes: an image forming section that forms an image; and an image forming control section that acquires information on a detection result of the image by a first image detecting section which has relatively higher failure detection accuracy than that of a second image detecting section, and information on a detection result of the image by the second image detecting section which has relatively higher color measurement accuracy than that of the first image detecting section, wherein the image forming control section acquires second image detection information in a region that has been detected by the second image detecting section and in which an exclusion detection region has been removed, based on the exclusion detection region that has been determined to contain a failure in the image, by first image detection information based on the detection result of the first image detecting section.

Abstract: A fixing device includes: a fixing member; a pressure member pressed against the fixing member; a plurality of halogen lamp heaters configured to heat the fixing member; a temperature detecting unit configured to detect a temperature of the fixing member; and a control unit configured to perform half-wave control on at least one first halogen lamp heater by calculating an output Duty and performing energization or de-energization for each half-wave of an AC waveform, and perform switch on/off control on a second halogen lamp heater, the second halogen lamp heater being other than the first halogen lamp heater, wherein the first halogen lamp heater and the second halogen lamp heater have reference voltages satisfying the reference voltage of the first halogen lamp heater<the reference voltage of the second halogen lamp heater, the reference voltages being set in accordance with densities of contained halogen gases.

Abstract: An image reading apparatus and an image forming system are provided which can reduce the influence of magnification error, detect patches in correct positions, and save the sheets required for adjusting an image. The image reading apparatus makes use of an image scanner which reads patches printed on a sheet P, a spectral colorimeter which colorimetrically measures the patches read by the image scanner, and is provided with a timing compensation unit which compensates the colorimetric measurement timing with which colorimetric operation of the spectral colorimeter is triggered based on the positional information of the patches read by the image scanner, and an image correction unit which corrects the color information of the patches read by the image scanner based on the colorimetric values of the patches colorimetrically measured by the spectral colorimeter.

Abstract: An image forming apparatus includes: an image forming section that forms an image; and an image forming control section that acquires information on a detection result of the image by a first image detecting section which has relatively higher failure detection accuracy than that of a second image detecting section, and information on a detection result of the image by the second image detecting section which has relatively higher color measurement accuracy than that of the first image detecting section, wherein the image forming control section acquires second image detection information in a region that has been detected by the second image detecting section and in which an exclusion detection region has been removed, based on the exclusion detection region that has been determined to contain a failure in the image, by first image detection information based on the detection result of the first image detecting section.

Abstract: A fixing device includes: a fixing member; a pressure member pressed against the fixing member; a plurality of halogen lamp heaters configured to heat the fixing member; a temperature detecting unit configured to detect a temperature of the fixing member; and a control unit configured to perform half-wave control on at least one first halogen lamp heater by calculating an output Duty and performing energization or de-energization for each half-wave of an AC waveform, and perform switch on/off control on a second halogen lamp heater, the second halogen lamp heater being other than the first halogen lamp heater, wherein the first halogen lamp heater and the second halogen lamp heater have reference voltages satisfying the reference voltage of the first halogen lamp heater<the reference voltage of the second halogen lamp heater, the reference voltages being set in accordance with densities of contained halogen gases.

Abstract: A colorimetric device includes: a feeding unit configured to feed a transfer medium; a colorimeter configured to perform colorimetry of an image that is formed on the transfer medium and that has a color boundary in a feeding direction; and a colorimetry control unit configured to control the feeding unit and the colorimeter, wherein the colorimetry control unit acquires color information related to the color boundary of the image and determines the color boundary of the image based on the color information and a result of the colorimetry performed by the colorimeter.

Abstract: A fixing device includes a roller, a plurality of heaters, a temperature detection unit, and a control unit, wherein when the temperature detection unit detects that the temperature of longitudinal end portions of the roller is lower than a preset reference temperature, the control unit performs full-lighting control on the heater with the largest amount of heat supply to the end portions of the roller, out of the plurality of heaters, and performs lighting control on the heater with the second largest amount of heat supply to the end portions of the roller in a pattern at a predetermined duty ratio, or performs lighting control on the heater with the largest amount of heat supply to the end portions of the roller in a pattern at a predetermined duty ratio, and turns off the heater with the second largest amount of heat supply to the end portions of the roller.

Abstract: An image-forming apparatus contains a control portion, a thermopile sensor, a temperature sensor, a fan, a heater, a guide plate temperature detection sensor, an external air temperature detection sensor, a fixing temperature detection sensor and the color sensor. The control portion calculates estimated sheet temperature of the conveying sheet using information such as guide plate temperature, external air temperature, fixing temperature and paper weight. The control portion controls the fan or the heater to drive so that sensor temperature of the thermopile sensor approaches the estimated sheet temperature of the sheet. The control portion controls the thermopile sensor to carry out a measurement of the temperature of the sheet when the sensor temperature falls within a set range in relation to the estimated sheet temperature.

Abstract: An image reading apparatus and an image forming system are provided which can reduce the influence of magnification error, detect patches in correct positions, and save the sheets required for adjusting an image. The image reading apparatus makes use of an image scanner which reads patches printed on a sheet P, a spectral colorimeter which colorimetrically measures the patches read by the image scanner, and is provided with a timing compensation unit which compensates the colorimetric measurement timing with which colorimetric operation of the spectral colorimeter is triggered based on the positional information of the patches read by the image scanner, and an image correction unit which corrects the color information of the patches read by the image scanner based on the colorimetric values of the patches colorimetrically measured by the spectral colorimeter.

Abstract: An image-forming apparatus contains a control portion, a thermopile sensor, a temperature sensor, a fan, a heater, a guide plate temperature detection sensor, an external air temperature detection sensor, a fixing temperature detection sensor and the color sensor. The control portion calculates estimated sheet temperature of the conveying sheet using information such as guide plate temperature, external air temperature, fixing temperature and paper weight. The control portion controls the fan or the heater to drive so that sensor temperature of the thermopile sensor approaches the estimated sheet temperature of the sheet. The control portion controls the thermopile sensor to carry out a measurement of the temperature of the sheet when the sensor temperature falls within a set range in relation to the estimated sheet temperature.

Abstract: A fixing device includes a roller, a plurality of heaters, a temperature detection unit, and a control unit, wherein when the temperature detection unit detects that the temperature of longitudinal end portions of the roller is lower than a preset reference temperature, the control unit performs full-lighting control on the heater with the largest amount of heat supply to the end portions of the roller, out of the plurality of heaters, and performs lighting control on the heater with the second largest amount of heat supply to the end portions of the roller in a pattern at a predetermined duty ratio, or performs lighting control on the heater with the largest amount of heat supply to the end portions of the roller in a pattern at a predetermined duty ratio, and turns off the heater with the second largest amount of heat supply to the end portions of the roller.

Abstract: An image forming apparatus includes first and second image-forming portions and an intermediate transporting portion. A control unit checks fixing units in the image-forming portions and determines whether or not the fixing unit in the first image-forming portion is a fixing unit for an envelope. If not, the control unit controls a manipulation and display unit to display guidance for urging a user to exchange the first fixing unit. If so, the control unit determines whether or not too fixing unit in the second image-forming portion is a fixing unit for an envelope. If not, the control portion controls a manipulation and display unit to display a guidance for urging a user to exchange the second fixing unit. If both of fixing units in the first and second image-forming portions are fixing units for the envelope, the control unit allows an envelope mode control operation.

Abstract: In a serial tandem image forming system having a plurality of image forming apparatuses, a double-side printing job can be performed in a way according to the needs of users by taking into consideration an adjustment operation. The serial tandem image forming system includes an upstream apparatus 200 and a downstream apparatus 300, as the image forming apparatuses, each of which is capable of forming images on both sides of a sheet. When receiving a double-side printing job while one of the image forming apparatuses is performing the adjustment operation, a control unit 260 displays information on a manipulation display 500 which prompts a user to select whether to immediately start the job by performing a single machine double-side printing process with the other image forming apparatus, or start the job by shifting to a tandem mode and performing a serial double-side printing process after the adjustment operation has finished.

Abstract: An image forming system has a first image forming section to form an image on a sheet, wherein the first image forming section heats the sheet to fix the image on the sheet, a second image forming section to form an image to the sheet on which the image has been formed by the first image forming section, and a transporting section to transport the sheet from first image forming section to the second image forming section. The transporting section has a first transporting part to transport the sheet to a predetermined position, and a second transporting part to reverse a surface of the sheet which has been transported by the first transporting part as transporting the sheet from the predetermined position to an area below the predetermined position.

Abstract: In a serial tandem image forming system having a plurality of image forming apparatuses, a double-side printing job can be performed in a way according to the needs of users by taking into consideration an adjustment operation. The serial tandem image forming system includes an upstream apparatus 200 and a downstream apparatus 300, as the image forming apparatuses, each of which is capable of forming images on both sides of a sheet. When receiving a double-side printing job while one of the image forming apparatuses is performing the adjustment operation, a control unit 260 displays information on a manipulation display 500 which prompts a user to select whether to immediately start the job by performing a single machine double-side printing process with the other image forming apparatus, or start the job by shifting to a tandem mode and performing a serial double-side printing process after the adjustment operation has finished.

Abstract: An image forming apparatus includes first and second. image-forming portions and an intermediate transporting portion. A control unit checks fixing units in the image-forming portions and determines whether or not the fixing unit, in the first image-forming portion is a fixing unit for an envelope. If not, the control unit controls a manipulation and display unit to display guidance for urging a user to exchange the first fixing unit. If so, the control unit determines whether or not too fixing unit in the second image-forming portion is a fixing unit for an envelope. If not, the control portion controls a manipulation and display unit to display a guidance for urging a user to exchange the second fixing unit, If both of fixing units in the first and second image-forming portions are fixing units for the envelope, the control unit allows an envelope mode control operation.

Abstract: An image forming apparatus contains a first printer forming a first image on a surface of the sheet member, a reversing section reversing a surface of the sheet member and a second printer forming a second image on a back of the sheet member. The second printer contains a correction section correcting a deflection of the sheet member. A straight sheet-member-transporting path extends from the reversing section to the second printer. A distance between a position at which the sheet member enters the sheet-member-transporting path and a position at which the correction section corrects the deflection of the sheet member is set so as to be not smaller than a length of the sheet member having the largest size among the sheet members to be handled.

Abstract: An image forming system has a first image forming section to form an image on a sheet, wherein the first image forming section heats the sheet to fix the image on the sheet, a second image forming section to form an image to the sheet on which the image has been formed by the first image forming section, and a transporting section to transport the sheet from first image forming section to the second image forming section. The transporting section has a first transporting part to transport the sheet to a predetermined position, and a second transporting part to reverse a surface of the sheet which has been transported by the first transporting part as transporting the sheet from the predetermined position to an area below the predetermined position.

Abstract: Disclosed is an image reading method for reading an image on a document, including: reading cyclically the image in a main scanning direction with using an image pickup section, while relatively moving at least one of a light emitting section and the document irradiated by the light emitting section with a sub-scanning velocity in a sub-scanning direction perpendicular to the main scanning direction, against the image pickup section which comprises a plurality of light receiving elements in the main scanning direction; controlling, while the cyclic reading, a reading cycle in the main scanning direction to be inversely proportional to a magnification ratio; controlling, while the cyclic reading, light emitting intensity and light emitting period in the reading cycle to be constant irrespective of the magnification ratio; and controlling, while the cyclic reading, the sub-scanning velocity to be constant irrespective of the magnification ratio.