Canon Kabushiki Kaisha

Yasuhiro Saito

Yuichi Ikeda

Nobuatsu Sasanuma

Tetsuya Atsumi

Akihiro Sato

Toshiro Tomono

Toshihiko Kitahara

Rie Aizawa

An image forming system including: an image reading portion which reads an image of an original; an image forming portion which forms the image on a sheet based on image information read by the image reading portion; and a storing device which stores the original before the image is read, the original after the image is read, and the sheet on which the image has been formed based on the image information, wherein the storing device is detachable from the image forming system.

Image forming system and image reading apparatus

When pixels in a two-dimensional matrix are divided into lines A and B in the column (or row) direction (sub-scanning direction) and two neighboring pixels in the row (or column) direction are subjected to gradation correction respectively using characteristic curves for lines A and B, the characteristic curve for line B unpreferably has a stepwise characteristic portion having a step when it is stored in an LUT, due to quantization errors unique to digital values. Hence, the characteristic curve for line A is set to be decreased by the amount corresponding to the step.

Image processing apparatus and method

An image processing apparatus for performing pulse-width modulation processing based on input image data. A maximum pulse width of a pulse signal, which can be outputted as a modulation signal obtained by the pulse width modulation, is changed in accordance with an image processing mode.

Image information processing apparatus and method

An image forming apparatus forms an image on a medium by using an output device. A pattern signal for forming a predetermined pattern image on the medium is generated, and image forming parameters for the output device are determined on the basis of the density of the pattern image formed on the medium. The determined image forming parameters are transmitted via bidirectional communication to an external computer or other image forming apparatus.

A system which utilizes plural image forming apparatus, equalizes gradation characteristics of images commonly output from such plural image forming apparatus. When the system includes three color copying apparatus, at first a test pattern image based on data from a pattern generator is output from the color copying apparatus. The prepared image is read by the reader of the color copying apparatus, and, based on the read data, the correction data of a table (LUT) are calibrated for obtaining density data for a laser beam. The calibration of the correction data of the color copying apparatus are conducted in a similar manner using, however, the reader of the same copying apparatus for reading the test pattern. It is therefore, rendered possible to exclude the influence of the difference in the reader characteristics on the calibration, and to equalize the gradation characteristics when the copying apparatus are used as printers.

Growing community of inventors

Shizuoka-ken, Japan

Yasuhiro Saito