Abstract: In a method of forming an image in a form of pixels, the density distribution around a target pixel is obtained by processing image signals of pixels neighboring the target pixel. The target pixel is sub-divided into a plurality of sub-pixels which form of matrix of n rows.times.m columns. The sub density distribution of the sub-pixels in the target pixel is assumed from the density distribution of the neighboring pixels. The density of each of sub-pixels is determined by multiplying the density of the target pixel, by a constant P and a density ratio of the corresponding sub-pixels in the sub density distribution.
Abstract: An image forming apparatus including an electrophotographic photosensitive member; a latent image forming device for forming an electrostatic latent image by charging the photosensitive member and exposing it to light information; a controller for controlling the latent image forming means to control tone reproducibility of the electrostatic latent image; an image forming device for forming an image having light, halftone and dark portions, for tone controls, a detector for detecting a state of the tone control image, and wherein the controller controls the electrostatic latent image forming device on the basis of a datum from the detector and predetermined tone correcting information.
Abstract: A dry-type toner is temporarily put on a printing paper with electrification by an electrifying unit and a toner supplying unit. A laser diode is driven on the basis of a video signal to emit a laser beam by which the dry-type toner put on the printing paper is melted and fixed thereon. A remaining toner that was not melted on the printing paper is eliminated by a cleaning unit. A printing by the laser beam can be realized most easily without using expensive parts such as a photosensitive material or the like and without increasing its mechanism and circuit scale.
Abstract: In an apparatus for forming an electrostatic latent image in a form of dot for each pixel on a photoreceptor, each pixel has plural color component signals and a dot is formed for each of color component signals in the same imaging unit area. A signal processing circuit processes specific color component signals of pixels neighboring a target pixel to obtain a density distribution around the target pixel, and determines a recording position of the dot in the recording unit area for each of the plural color component signals on the basis of the density distribution.
Abstract: In an electrophotographic image forming apparatus including a charger for electrically charging the photoconductor to a predetermined initial electric potential, a laser projects a light onto the photoconductor so as to form an electrostatic latent image thereon, and a developing device develops the latent image with toner so as to form a toner image thereon. Further, a charger controller controls the charger based on a detection result of a detector for detecting a state of the photoconductor so that the initial electric potential of the photoconductor changes in a predetermined range, and a selection controller selects one of the plurality of gradation correction data stored in a storage unit based on the detection result of the detector when the initial electric potential of the photoconductor is an upper or lower limit value of the predetermined range.
Abstract: This invention modifies printing information from a laser scanner to improve the appearance of printed matter. This improvement takes into account the image data of a target pixel to be printed and the image data of adjacent pixels located before and after the target pixel, the pulse position of the target pixel. An operator can select whether to shift the radiation timing of a laser beam to the left or the right within one pixel, and whether to squeeze the laser beam to reduce its beam size or broaden it to increase its beam size.
Abstract: An image processing apparatus in which a density pattern is generated which corresponds to input image data. Growth direction of the density pattern is controlled by generating a density pattern in a prescribed direction, and generating a density pattern in a direction based on a random signal. As a result, when printing the image data based on the generated density patterns, there is no joining between adjacent pixels and a high-quality image is produced.
Abstract: In a digital image forming apparatus with use of electrophotographic process, an electrostatic latent image is formed by modulating the intensity of laser beam according to image data to expose a photoconductor in the raster scan to form an electrostatic latent image. A scan line is divided into groups of consecutive dots, and the exposure of the photoconductor with the beam is allowed only for a predetermined light-emitting time within the time needed to scan a predetermined period of consecutive dots in the scan line direction. Thus, the exposure is stopped periodically and the smoothness of a reproduced image is improved.
Abstract: A printing machine having an imaging surface, a scanning system for modulating a beam and scanning an image onto the imaging surface, a device to designate a variable relative darkness factor, a store for holding a partial array of the image to be reproduced, a comparator for relating the partial array of the image to be reproduced with standard reference formats to produce correlation signals, modulating logic responsive to the correlation signals and the variable relative darkness factor to provide timing adjustments and a modulator for modulating the beam and scanning the image onto the imaging surface in response to the timing adjustments.
Abstract: A voltage is selectively applied between two electrodes (emitter and gate) disposed at a short distance to create an intense electric field between the electrodes. Electrons emitted by the field emission are accelerated by the intense electric field and collide against a fluorescent layer so that light can be emitted from portions of the fluorescent layer. With a recording head of the above construction, an electrostatic latent image is formed on a photosensitive drum.
Type:
Grant
Filed:
March 30, 1993
Date of Patent:
March 28, 1995
Assignee:
Kabushiki Kaisha Toshiba
Inventors:
Hitoshi Nagato, Yuzo Koike, Shuzo Hirahara, Masafumi Mori