Canon Kabushiki Kaisha

Hideyuki Nagata

Yushi Oka

Akihiko Sato

Toru Ono

Shigemichi Hamano

Shigeo Yamagata

An image forming apparatus that is capable of carrying out image formation on a recording medium such as plain paper without increasing the FCOT (First Copy Out Time) and is also capable of carrying out optimal image formation on a recording medium, such as thick paper, for which the processing speed is reduced with no registration misalignment between the leading ends of toner images and the leading end of the recording medium. An image is primarily transferred onto a rotatively driven image carrier, and the image on the image carrier is secondarily transferred onto a recording medium. An image writing reference position signal for starting image formation is issued based on the circumference of the image carrier which is the length of the image carrier in the direction of rotation thereof or based on a detected reference position on the image carrier. A user can selectively switch, through operation of an operating section, between the issuing of the image writing reference position signal based on the circumference of the image carrier and the issuing of the image writing reference position signal based on the detected reference position.

Image forming apparatus and image forming control method

In an image forming apparatus for forming a binarized image upon adding on additional information without degrading image quality, a mode signal assumes an 'H' or 'L' level. When the mode signal is at the 'H' level, a pattern in which a binarized output attains the 'H' level for two successive pixels appears in a low-density area of the image formed, thereby indicating the start of data representing additional information. When the mode signal is at the 'L' level, additional information is represented by the level of a control signal f. The binarized output is controlled in such a manner that the spacing of black pixels becomes an odd number of pixels in a low-density area of the formed image in a case where the control signal f is at the 'L' level and an even-number of pixels in the low-density area of the formed image in a case where the control signal f is at the 'H' level. In other words, the additional information is expressed by indicating '0' when the spacing of black pixels is an odd number and '1' when the spacing of black pixels is an even number.

Growing community of inventors

Ibaraki, Japan

Hideyuki Nagata