Abstract: A control device selects one of a plurality of chromatic colors as a target chromatic color according to a consumption status of developing agents of the plurality of chromatic colors. The control device causes an image forming portion to execute a process of forming, on a surface of a transfer medium, a plurality of chromatic color test images of the plurality of chromatic colors, and a superimposed test image in which a black test image is superimposed on a background image of the target chromatic color. The control device acquires a test detection signal of an amount of diffuse reflection light in each of areas of the plurality of chromatic color test images and the superimposed test image on the surface of the transfer medium. The control device adjusts timing of image formation of the plurality of colors by the image forming portion based on the test detection signal.

Abstract: A control portion causes an image forming portion to execute a test output process in which a plurality of test toner images each having a different developing voltage condition are formed in sequence on a surface of each of a plurality of image-carrying members and then transferred to an intermediate transfer body. The control portion sequentially selects, from the plurality of image-carrying members, target image-carrying members that are arranged at a distance greater than an arrangement spacing of the plurality of image-carrying members, and causes the image forming portion to execute the test output process so that each time one of the plurality of target image-carrying members is selected, the plurality of test toner images for each of the plurality of target image-carrying members are transferred within an area on the surface of the intermediate transfer body whose length corresponds to pacing between the plurality of target image-carrying members.

Abstract: An optical system used in an optical apparatus is configured to include a first lens group having positive refractive power, a focusing group that moves along an optical axis at focusing, and a rear group, in order from an object side, so that the first lens group includes a first-A lens group disposed on the object side of the largest air space A in the first lens group, and that all of the following conditional expressions are satisfied: 1.00<FNo×(TL/f)2<2.50 and 0.30<dA/dG1<0.85 where FNo is the f-number of the optical system focusing on infinity, TL is the total optical length of the optical system focusing on infinity, f is the focal length of the optical system focusing on infinity, dA is the length on the optical axis of the air space A, and dG1 is the length on the optical axis of the first lens group.

Abstract: An image forming apparatus includes a second acquisition processing portion and a third acquisition processing portion. The second acquisition processing portion acquires a first toner image forming condition of a toner image forming portion. The third acquisition processing portion acquires, based on the first toner image forming condition acquired by the second acquisition processing portion, a relational expression that indicates a relationship between a second toner image forming condition of the toner image forming portion and a toner concentration of a specific toner image that is formed by the toner image forming portion. Further, the third acquisition processing portion uses specific expressions that respectively correspond to a plurality of coefficients included in the relational expression to calculate the plurality of coefficients corresponding to the first toner image forming condition acquired by the second acquisition processing portion.

Abstract: An image forming apparatus includes an image forming portion, an exposure device, an image density sensor, and a control portion. The control portion can, by adjusting the development voltage based on the image density of a reference image and the amount of exposure from the exposure device, perform image density correction to adjust the image density. The control portion predicts the toner charge amount based on a formation condition of the reference image and the image density of the reference image and determines the timing of performing the image density correction next time based on the rate of change of the toner charge amount calculated using a first toner charge amount predicted when the image density correction was performed last time, a second toner charge amount predicted when the image density correction is performed this time, and the interval between the image density correction performed last time and this time.

Abstract: A control portion, by an image density sensor detecting density of reference images for image density correction formed by a plurality of image forming portions, adjusts a developing voltage and an exposure amount of an exposure device based on the detection result. The control portion, based on the density of the reference images detected by the image density sensor, sets a common developing voltage such that the densities of the reference images are equal to or higher than a target density in all of the two or more image forming portions among the plurality of image forming portions. The control portion, by adjusting a toner adhesion area ratio for image forming portions of the two or more image forming portions in which the densities of the reference images exceed the target density when a common developing voltage is set, adjusts the densities of the reference images to the target density.

Abstract: An optical system used in an optical apparatus is configured to include a first lens group having positive refractive power, a focusing group that moves along an optical axis at focusing, and a rear group, in order from an object side, so that the first lens group includes a first-A lens group disposed on the object side of the largest air space A in the first lens group, and that all of the following conditional expressions are satisfied: 1.00<FNo×(TL/f)2<2.50 and 0.30<dA/dG1<0.85 where FNo is the f-number of the optical system focusing on infinity, TL is the total optical length of the optical system focusing on infinity, f is the focal length of the optical system focusing on infinity, dA is the length on the optical axis of the air space A, and dG1 is the length on the optical axis of the first lens group.

Abstract: The mode setting unit sets the mode of the display unit to a blind mode. An operation for the mode setting unit to set the mode of the display unit to the blind mode is input to the input unit. The image changing unit changes the mode of the display unit from the normal mode to the blind mode based on the operation input to the input unit, and changes at least one of the color and density of the display image of the display unit according to the blind mode. When an operation for setting the mode of the display unit to the blind mode is input to the input unit, the display unit displays a preview image obtained by changing the image data before the image forming unit forms on the sheet in accordance with the blind mode as the display image of the display screen.

Abstract: A belt member includes: a strip member having an elongate shape; a fastener disposed along the longitudinal direction of the strip member; and an opening-closing device that opens or closes the fastener. For reducing a contact pressure of the belt member per unit area, the fastener is opened by the opening-closing device to unfold the belt member into a form of a wide strip so that the width of the belt member is increased. On the other hand, when the fastener is closed by the opening-closing device, the belt member takes a form of a narrow tube so that the width of the belt member is reduced.

Abstract: A belt member includes: a strip member having an elongate shape; a fastener disposed along the longitudinal direction of the strip member; and an opening-closing device that opens or closes the fastener. For reducing a contact pressure of the belt member per unit area, the fastener is opened by the opening-closing device to unfold the belt member into a form of a wide strip so that the width of the belt member is increased. On the other hand, when the fastener is closed by the opening-closing device, the belt member takes a form of a narrow tube so that the width of the belt member is reduced.

Abstract: A database system which quickly creates a snapshot copy of the backup files. The system has a plurality of database storage subsystems which are normally operating as a mirrored storage system under the control of a mirroring controller. A write suspending unit temporarily suspends write operations to those storage subsystems, and a device detachment unit detaches at least one of the database storage subsystems from the mirrored storage system. A write restarting unit then allows write operations to the remaining database storage subsystems. A correction processor makes corrections to the detached database storage subsystem to resolve any inconsistency in its records, which might have been introduced in relation with such transactions that were in process at the time of the detachment. A data converter converts file location data for the detached database storage subsystem, so that it will serve as a separate database volume.

Abstract: A database system which quickly creates a snapshot copy of the backup files. The system has a plurality of database storage subsystems which are normally operating as a mirrored storage system under the control of a mirroring controller. A write suspending unit temporarily suspends write operations to those storage subsystems, and a device detachment unit detaches at least one of the database storage subsystems from the mirrored storage system. A write restarting unit then allows write operations to the remaining database storage subsystems. A correction processor makes corrections to the detached database storage subsystem to resolve any inconsistency in its records, which might have been introduced in relation with such transactions that were in process at the time of the detachment. A data converter converts file location data for the detached database storage subsystem, so that it will serve as a separate database volume.

Abstract: An exclusive control system of a shared resource in the computer system is comprised of: an exclusive control management table constructed of a lock word and a lock queue header, a management region allocated to the respective executable members for storing therein the executable member identifying information of the allocated executable member; resource management means for swapping a content of a management region allocated to a requesting executable member for a content of the lock queue header of the exclusive control management table upon receipt of the request to acquire the use right of the shared resource from the executable member, or a request to release the use right from the executable member, thereby producing a quasi-queue for chaining the executable members that have requested to acquire the use right while another executable member acquires the use right; and executable member control means for suspending a process operation of such an executable member which is brought into a waiting state in