Abstract: An image forming apparatus including: a developing roller configured to develop an electrostatic latent image on a photosensitive drum to form a toner image; a belt onto toner image is transferred; a detection unit configured to detect a density of an image for detection formed on the belt; and a controller configured to perform hue adjustment based on a detection result of the detection unit, wherein the image forming apparatus performs image formation in a second mode using a color gamut different from a color gamut in a first mode, and the controller obtains a lookup table, which indicates a correlation between image data to be used and input image data in the second mode, based on the detection result in the first mode and a correlation of density between the first mode and the second mode.

Abstract: An image forming apparatus includes a CPU configured to change a parameter value used to control a developer bearing amount and form a plurality of patches for different parameter values changed, and a color sensor configured to measure the plurality of patches thereby acquiring color information thereof. The CPU detects, from values of color information of the plurality of patches, a value of the color information at which a change greater than or equal to a predetermined threshold value occurs, and the CPU sets a parameter used in forming an image based on the detected value of color information.

Abstract: An image forming apparatus includes a controller capable of executing a normal mode in which an electrostatic image formed on an image bearing member is developed by setting a peripheral velocity ratio of a developer bearing member relative to the image bearing member to a prescribed peripheral velocity ratio, and a color gamut enlargement mode in which a color gamut of an image to be formed on a recording medium is enlarged as compared to the normal mode by setting the peripheral velocity ratio of the developer bearing member relative to the image bearing member to a larger peripheral velocity ratio than the peripheral velocity ratio in the normal mode, wherein the controller identifies image color gamut information included in image data and forms an image by selecting the normal mode or the color gamut enlargement mode in accordance with the image color gamut information.

Abstract: A color measurement device includes a light source for illuminating an object with light; a dispersing portion for spectrally dispersing light emitted and reflected by the object; a light receptor for receiving the light dispersed by the dispersing portion; and a controller for effecting color measurement based on a result of light reception of the light receptor from the object which is an image formed on a recording material; wherein the emitted light has a first intensity of light in a first wavelength range and a second intensity lower than the first intensity in a second wavelength range, and wherein the controller deduces a value relating to color measurement for the second wavelength range on the basis of a result of light reception of the light receptor for the first wavelength range.

Abstract: Changing of a peripheral speed ratio, resulting in change of the developer amount per unit area, enables the detection unit to detect the developer amount with sufficient accuracy.

Abstract: A control portion has a conversion portion that converts image data to be used for forming a recorded image by using either a first conversion condition which has been set such as to obtain a first gradation characteristic in the image to be formed on the recording material when a first image forming operation is executed or a second conversion condition which has been set such as to obtain a second gradation characteristic, which is different from the first gradation characteristic, in the image when a second image forming operation is executed, a peripheral velocity ratio between an image bearing member and a developer bearing member being larger during the second image forming operation than during the first image forming operation, and enables the first image forming operation or the second image forming operation to be performed on the basis of converted image data.

Abstract: In a first image formation mode, an image is formed with a first development contrast C1 and a specific dot pattern is formed with a second development contrast C2, which is lower than the first development contrast C1; in a second image formation mode, an image is formed with a third development contrast C3 and a specific dot pattern is formed with a fourth development contrast C4, which is lower than the third development contrast C3; and when ?C1 (=C2/C1) denotes a ratio between the second development contrast C2 and the first development contrast C1, and ?C2 (=C4/C3) denotes a ratio between the fourth development contrast C4 and the third development contrast C3, ?C2<?C1 is satisfied.

Abstract: In a first image formation mode, an image is formed with a first development contrast C1 and a specific dot pattern is formed with a second development contrast C2, which is lower than the first development contrast C1; in a second image formation mode, an image is formed with a third development contrast C3 and a specific dot pattern is formed with a fourth development contrast C4, which is lower than the third development contrast C3; and when ?C1 (=C2/C1) denotes a ratio between the second development contrast C2 and the first development contrast C1, and ?C2 (=C4/C3) denotes a ratio between the fourth development contrast C4 and the third development contrast C3, ?C2<?C1 is satisfied.

Abstract: An image forming apparatus includes a CPU configured to change a parameter value used to control a developer bearing amount and form a plurality of patches for different parameter values changed, and a color sensor configured to measure the plurality of patches thereby acquiring color information thereof. The CPU detects, from values of color information of the plurality of patches, a value of the color information at which a change greater than or equal to a predetermined threshold value occurs, and the CPU sets a parameter used in forming an image based on the detected value of color information.

Abstract: A control portion has a conversion portion that converts image data to be used for forming a recorded image by using either a first conversion condition which has been set such as to obtain a first gradation characteristic in the image to be formed on the recording material when a first image forming operation is executed or a second conversion condition which has been set such as to obtain a second gradation characteristic, which is different from the first gradation characteristic, in the image when a second image forming operation is executed, a peripheral velocity ratio between an image bearing member and a developer bearing member being larger during the second image forming operation than during the first image forming operation, and enables the first image forming operation or the second image forming operation to be performed on the basis of converted image data.

Abstract: An image forming apparatus includes a controller capable of executing a normal mode in which an electrostatic image formed on an image bearing member is developed by setting a peripheral velocity ratio of a developer bearing member relative to the image bearing member to a prescribed peripheral velocity ratio, and a color gamut enlargement mode in which a color gamut of an image to be formed on a recording medium is enlarged as compared to the normal mode by setting the peripheral velocity ratio of the developer bearing member relative to the image bearing member to a larger peripheral velocity ratio than the peripheral velocity ratio in the normal mode, wherein the controller identifies image color gamut information included in image data and forms an image by selecting the normal mode or the color gamut enlargement mode in accordance with the image color gamut information.

Abstract: In a first image formation mode, an image is formed with a first development contrast C1 and a specific dot pattern is formed with a second development contrast C2, which is lower than the first development contrast C1; in a second image formation mode, an image is formed with a third development contrast C3 and a specific dot pattern is formed with a fourth development contrast C4, which is lower than the third development contrast C3; and when ?C1 (=C2/C1) denotes a ratio between the second development contrast C2 and the first development contrast C1, and ?C2 (=C4/C3) denotes a ratio between the fourth development contrast C4 and the third development contrast C3, ?C2<?C1 is satisfied.

Abstract: Changing of a peripheral speed ratio, resulting in change of the developer amount per unit area, enables the detection unit to detect the developer amount with sufficient accuracy.

Abstract: The colorimetry apparatus includes a light source for emitting light to a surface of a detected object, a diffraction grating for spectrally separating, for each wavelength, the light emitted from the light source and reflected by the detected object, and a line sensor including multiple pixels, for receiving the light, which is spectrally separated by the diffraction grating, for the each wavelength by the multiple pixels. The light source and the line sensor are arranged on the common substrate.

Abstract: A transducer in the form of cloth having high flexibility obtained by manufacturing a conventional woven or knitted fabric structure using general-purpose fiber materials. The transducer includes piezoelectric units, each including two conductive fibers and one piezoelectric fiber arranged substantially on the same plane in the order of the conductive fiber, the piezoelectric fiber and the conductive fiber, and outputs and inputs an electric signal.

Abstract: An image forming apparatus includes a mounting portion to and from which a process cartridge including a photosensitive member and a developing roller is attachable and detachable, a separation mechanism that takes a first position to separate the developing roller from the photosensitive member and a second position to bring the developing roller into contact with the photosensitive member, an allowance mechanism that allows the process cartridge with the developing roller kept in contact with the photosensitive member to be mounted on the mounting portion when the separation mechanism is in the first position, an exposure device, and a control unit, wherein, when the developing roller and the photosensitive member are in contact with each other when the separation mechanism is in the first position, the control unit performs an exposure operation while keeping the separation mechanism in the first position during an initial operation of the image forming apparatus.

Abstract: A color measurement device includes a light source for illuminating an object with light; a dispersing portion for spectrally dispersing light emitted and reflected by the object; a light receptor for receiving the light dispersed by the dispersing portion; and a controller for effecting color measurement based on a result of light reception of the light receptor from the object which is an image formed on a recording material; wherein the emitted light has a first intensity of light in a first wavelength range and a second intensity lower than the first intensity in a second wavelength range, and wherein the controller deduces a value relating to color measurement for the second wavelength range on the basis of a result of light reception of the light receptor for the first wavelength range.

Abstract: A fibrous or cloth piezoelectric element capable of extracting an electric output with relatively small stress produced by rubbing the surface with a finger. The piezoelectric element includes a piezoelectric unit including two conductive fibers and one piezoelectric fiber, all of which are arranged substantially on the same plane while they have contact points between them.

Abstract: An image forming apparatus includes a mounting portion to and from which a process cartridge including a photosensitive member and a developing roller is attachable and detachable, a separation mechanism that takes a first position to separate the developing roller from the photosensitive member and a second position to bring the developing roller into contact with the photosensitive member, an allowance mechanism that allows the process cartridge with the developing roller kept in contact with the photosensitive member to be mounted on the mounting portion when the separation mechanism is in the first position, an exposure device, and a control unit, wherein, when the developing roller and the photosensitive member are in contact with each other when the separation mechanism is in the first position, the control unit performs an exposure operation while keeping the separation mechanism in the first position during an initial operation of the image forming apparatus.

Abstract: An image forming apparatus, which is configured to form an image on a sheet, includes an image forming unit configured to form an unfixed toner image on the sheet, and a fixing unit configured to fix the unfixed toner image to the sheet by heating the sheet bearing the unfixed toner image while conveying the sheet by a fixing nip portion. The image forming apparatus can perform a cleaning mode for cleaning the fixing unit by conveying a sheet with an unfixed toner image for cleaning formed thereon by the fixing nip portion. At a time of the cleaning mode, the image forming unit forms the unfixed toner image for cleaning on a sheet surface opposite from a sheet surface where the unfixed toner image is formed at a time of image formation.