An image forming apparatus including an image forming unit that forms an image, an intermediate transfer member for a measuring image, a measurement unit that measures the measuring image, a conversion unit that converts a measurement result of the measuring image on a basis of a conversion condition, a determination unit that determines an image forming condition on a basis of the converted measurement result, and an update unit that updates the conversion condition while forming and measuring first measuring images, converting the measurement results of the first measuring images, determining a measuring image forming condition on a basis of the converted measurement results, forming second measuring images on a basis of the measuring image forming condition, obtaining measuring results of the second measuring images output from another measuring unit, and updating the conversion condition on a basis of the measurement results of the second measuring images.

An image forming apparatus includes a converting unit, a plurality of image forming units, a scanning unit, a first generating unit, a second generating unit, an intermediate transfer member, a measuring unit, and a controller configured to, after the first generating unit generates an image forming condition, control the plurality of image forming units to form a measurement image, control the measuring unit to measure the measurement image, and control whether to control the second generating unit to generate a conversion condition or not on the basis of a result of the measurement performed on a previous measurement image and a result of the measurement performed on a current measurement image.

An image forming apparatus includes: a density unevenness measurement mode processing portion that, in a density unevenness measurement process, detects density of a density unevenness measurement toner image, which has been formed in a rotational direction of the photoreceptor drum, multiple times in the rotational direction and captures in a memory portion all detected density information associating thereof with rotation phases of the photoreceptor drum; and an image quality adjustment processing portion that, in an image quality adjustment mode, detects density of an image quality adjustment toner image, which has been formed at any position in the rotational direction of the photoreceptor drum, in the rotational direction and corrects detected density information based on density information associated with a rotation phase matching a rotation phase where density of the image quality adjustment toner image has been detected among said all density information having been captured in the memory portion by the density unevenness measurement processing portion.

An image forming apparatus includes a photosensitive member, an exposing unit exposes the photosensitive member to exposure light to form an electrostatic latent image, a developing unit develops the electrostatic latent image to form an image, an intermediate transfer member onto which the image on the photosensitive member is transferred, a measurement unit measures a measurement image on the intermediate transfer member, an adjustment unit adjusts gradation characteristics based on the measurement result of the measurement unit, and correction unit corrects intensity of the exposure light for each of a plurality of positions on the photosensitive member in a scanning direction. the correction unit corrects the intensity based on the correction amount with respect to the intensity corresponding to a predetermined position. the predetermine position corresponds to a position in the scanning direction, at which the measurement image is formed.

An image forming apparatus forms a first image by adjusting a photosensitive member potential to a first charging potential and adjusting a developing potential to a first developing potential, and forms a second image by adjusting the member potential to a second charging potential, adjusting the developing potential to a second developing potential, but not causing an exposure unit to expose a photosensitive member, and forms a third image by adjusting the developing potential to a third developing potential, but not causing a charging unit to charge the member, and not causing the exposure unit to expose the member, and detects a streak image based on read data of the first, second and third images, and read data corresponding to a non-image region of the test sheet.

An image forming apparatus includes: a controller configured to compare a threshold value and an output value corresponding an intensity of the light reflected from the detection image, and to detect the color misregistration amount based on a comparison result; an update unit configured to update the threshold value based on a previous output value corresponding to the intensity of the light reflected from the detection image; and an adjustment unit configured to adjust an emission intensity of the light emitting element. The update unit updates, in a case when the emission intensity is adjusted, the threshold value based on the previous output value, a previous emission intensity, and the emission intensity adjusted by the adjustment unit.

An image forming apparatus includes: an image carrier that carries and transports a latent image; a charging member that is arranged to be in contact with a surface of the image carrier; a developing device that supplies toner to the image carrier and forms a toner image; a density detection unit that detects a density of the toner image; a pattern detection unit that detects a predetermined density variation pattern based on a detection result of the density detection unit according to the toner image; and a determination unit that determines a state of the charging member based on the number of the predetermined density variation patterns detected within a predetermined period of time.

An image forming apparatus capable of controlling density of an output image with high accuracy regardless of variation of internal temperature. A controller controls an image forming unit to form a measurement image, controls a light receiving unit to receive reflected light from the measurement image, controls a conversion unit to convert an output value of the light receiving unit, and controls an image formation condition based on a value that is obtained by converting the output value. An adjustment unit controls the light receiving unit to receive reflected light from an image bearing member, and adjusts the emission light amount of an emission unit based on the reflected light from the image bearing member. A selection unit selects a conversion condition from among conversion conditions based on a reference temperature that is detected when the adjustment unit adjusts the emission light amount and a current temperature.

An image forming apparatus includes an image forming unit, a transfer unit, and a controller. The transfer unit transfers a developer image formed by the image forming unit onto a transfer object. The controller controls each of the image forming unit and the transfer unit on a basis of printing data. The controller performs a printing control to cause a first printing operation and a second printing operation to be executed. The first printing operation forms a first developer image directed to an entire pixel region of a print image and transfers the first developer image onto the transfer object. The second printing operation forms a second developer image directed selectively to a high-gradation pixel region and transfers the second developer image onto the transfer object. The high-gradation pixel region is a pixel region, having a gradation value equal to or greater than a threshold, of the print image.

A sensor includes a light emitter and a photodetector. The light emitter outputs light with which a toner pattern or a surface material of an image carrier is irradiated. The photodetector receives reflection light from the toner pattern or the surface material. The sensor light intensity control unit provides a control voltage to the light emitter and thereby controls light intensity of the light emitter. The density determining unit determines a toner density on the basis of output of the photodetector. Further, the density determining unit (a) determines as a correction parameter a first-order coefficient of the control voltage of the light emitter for an output voltage of the photodetector corresponding to reflection light from the surface material, (b) determines a correction amount corresponding to the correction parameter and the toner density, and (c) corrects the toner density on the basis of the correction amount.