Provided is an image formation device including a photoreceptor configured to carry a toner image and a developer configured to form the toner image on a surface of the photoreceptor and configured such that the developer is a replaceable development unit, the image formation device including: a development bias application section configured to apply a development bias to between the photoreceptor and the developer; a stabilization control section configured to perform image stabilization control of determining a development bias value to be used in future by changing the development bias while measuring a density of the toner image formed by the developer, thereby obtaining the toner image with a target density; and a life determination section configured to determine expiration of use of the development unit when the development bias value determined by the stabilization control falls outside a preset acceptable range.

The image processing apparatus of the present invention includes: an edge determination unit configured to detect an edge pixel to which a white pixel and a black pixel are adjacent in a first direction in an image in which each pixel is represented as a white pixel or a black pixel; a first detection unit configured to detect a number of consecutive pixels up to the edge pixel in the first direction in the image; a second detection unit configured to detect a number of consecutive pixels whose number of consecutive pixels in the first direction is larger than a first threshold in a second direction perpendicular to the first direction in the image; and a type determination unit configured to determine a type of the edge pixel based on detection results by the first detection unit and detection results by the second detection unit.

An image forming apparatus includes an image former; a detector; and a hardware processor that: calculates a minimum area for each of the plurality of tones based on image data of the image, calculates a density ratio between the densities before and after the transferring is made for each of the plurality of tones from the densities detected by the detector, extracts as a first area a minimum area of a tone corresponding to a density ratio which switches from less than a predetermined threshold to equal to or more than the threshold, and extracts as a second area a minimum area of a tone the density ratio of which is a maximum, and changes a setting of a dot size of the image so that a size of the second area becomes the same as a size of the first area until the next setting change is performed.

An image forming apparatus includes a memory and circuitry. The memory is configured to store a status of the image forming apparatus and a first detected density value obtained in a first tone correction based on a dither pattern. The circuitry is configured to calculate a difference between the status of the image forming apparatus upon the first tone correction and the status of the image forming apparatus upon a second tone correction following the first tone correction. The circuitry is further configured to calculate a correction value according to the difference in the status of the image forming apparatus, based on the first detected density value and a second detected density value obtained in the second tone correction based on a reference pattern.

An image forming apparatus includes an image bearer, an image forming unit, a toner image detecting unit, and a detection processing unit. The image bearer is configured to bear a toner image. The image forming unit is configured to sequentially form groups of pattern images for a plurality of colors in a sub-scanning direction of the image bearer, each of the groups including pattern images of the same color at a predetermined interval. The toner image detecting unit is configured to detect the pattern images formed on the image bearer. The detection processing unit is configured to recognize whether an interval between adjacent pattern images of the same color corresponds to a set interval, to exclude an image for which the interval does not correspond to the set interval among the detected pattern images.

A method of adjusting an imaging apparatus comprises printing a set of test patches, the set of test patches comprising a solid color patch, a grey level patch and a substrate patch. The optical densities of the set of test patches are determined. The method comprises simultaneously correcting a solid optical density value (Solid OD), relating to the solid color patch and an associated grey level (LUT) value relating to the grey level patch.

An image forming apparatus includes: an image forming part that forms a toner image on a recording medium; and a hardware processor that controls the image forming part, wherein the image forming part includes an image carrier, the hardware processor executes: a first adjustment process of adjusting the image forming part with use of a first image formation condition determined in accordance with a toner adhesion amount at a plurality of points in a first direction on the image carrier, and a second adjustment process of adjusting the image forming part with use of a second image formation condition determined in accordance with a toner adhesion amount at one point in a first direction on the image carrier, the image carrier rotates as a recording medium is conveyed, the first direction is a direction intersecting with a rotational direction of the image carrier.

An image forming apparatus includes a controller configured to execute: a task that measures a plurality of first color patterns; a task that, on the basis of a first output value corresponding to a measurement result of the first color patterns, determines a threshold value; a measurement task that measures a plurality of second color patterns; and a task that detects an amount of color misregistration on the basis of a result of a comparator comparing a second output value corresponding to a measurement result of the second color patterns with a threshold value corresponding to each of the second color patterns. In the measurement task, the controller controls whether or not to set the threshold value to the threshold value corresponding to each of the second color patterns on the basis of the first output value.

An image forming apparatus includes an image forming unit and a controller. The image forming unit includes a latent image bearer, a charger to charge the latent image bearer, an exposure device to expose a latent image on the surface of the latent image bearer, and a developing device to develop the latent image with a developer. The controller executes an image forming process, a first fluctuation control that cyclically changes a developing bias supplied to the developing device based on predetermined first pattern data, and a second fluctuation control that cyclically changes a charging bias supplied to the charger based on predetermined second pattern data, in parallel. The controller executes a determination process to determine whether the controller executes the first fluctuation control. When the controller determines not to execute the first fluctuation control, the controller determines not to execute the second fluctuation control, too.

A system and method for determining print cartridge authenticity in a printer includes an electrostatic process unit with a photoconductive drum configured to selectively generate a toner pattern from an associated toner cartridge based at least in part on electronic data associated with the toner cartridge. A transfer belt receives the toner pattern from the photoconductive drum and a sensor sensing the toner pattern on the transfer belt. A processor compares the toner pattern with a sensed toner pattern and generates an error condition when the toner pattern does not substantially match the sensed toner pattern. The toner includes an infrared reflective additive or an ultraviolet fluorescing additive and the sensor is configured to sense in the infrared or ultraviolet frequencies. The processor is configured to generate an error condition when the additive is not sensed by the sensor.