Samsung Electronics Co., Ltd.

Myong-hun Cho

Beom-ro Lee

Je-man Seo

A transfer belt driving control method and transfer belt driving control apparatus for color registration correction. The color registration correction method and apparatus performs the color registration correction by setting a pattern forming section, in which patterns for the color registration correction are able to be formed, and a non-pattern forming section, in which the patterns are not able to be formed, on a transfer belt in which the patterns are formed, performing the color registration correction by driving the transfer belt at a first speed in the pattern forming section, and driving the transfer belt at a second speed, which is faster than the first speed, in the non-pattern forming section.

Transfer belt driving control method and transfer belt driving control apparatus for color registration correction

An image forming apparatus includes a transport unit having a transport belt which transports a printing medium in a transport direction along a transport path, an image forming unit which transfers toner to the printing medium to form an image, a density evaluation unit which is provided on the transport path of the transport belt and evaluates a density of the image formed by the image forming unit, and a controller which controls the image forming unit to form a test image which has a length in a transport direction that is determined by a position deflection of the transport belt, controls a characteristic of the image forming unit based on a density evaluation of the test image, and controls the transport unit to make the transporting speed of the transport belt a predetermined value or less during the density evaluation of the test image by the density evaluation unit.

Image forming apparatus and control method thereof

A fixing device built in an electrophotographic image forming apparatus and a temperature control method for the fixing device are provided. The fixing device comprises a power supplying unit for supplying power to the fixing device; a control variable determination unit for determining control variables corresponding to operating states of the fixing device, wherein the control variables are used to control a temperature of the fixing device; a temperature detection unit for detecting the temperature of the fixing device; and a temperature control unit for controlling the temperature of the fixing device by using the control variables, wherein the temperature control unit comprises a duty ratio adjustment unit for adjusting a duty ratio of the supplied power based on the determined control variables. In addition, the control variable determination unit determines the control variables corresponding to at least one of a plurality of operating states.

Fixing device built in electrophotographic image forming apparatus, temperature control method for fixing device, and recording medium having embodied thereon computer program for the same

A halftone processing method for correcting the variation in light intensity on a photoconductive drum and an apparatus using the same, wherein the method includes the steps of preparing a plurality of dithering functions, detecting the position where image data for forming an electrostatic latent image is scanned on the photoconductive drum, selecting one of the plurality of dithering functions according to the detected scanning position, and halftone-processing the image data using the selected dithering function. Accordingly, the halftone processing method improves print quality by increasing light intensity at the edges of a photoconductive drum by permitting the laser printer to be halftone-processed using dithering functions whose critical values are different for the center and the edges of the photoconductive drum.

Growing community of inventors

Suwon-si, South Korea

Myong-hun Cho