Abstract: A developing apparatus includes a developer container for containing a developer; a developer bearing member for bearing the developer contained in the developer container, the developer bearing member having a surface layer containing substantially spherical particles, wherein a relation between a weight-average particle diameter r (.mu.m) of a toner in the developer and a volume-average particle diameter R (.mu.m) of the spherical particles satisfies an equation 0.5.ltoreq.R/r.ltoreq.1.9.

Abstract: A developing apparatus includes a developer container for containing a developer; a developer carrying member, disposed in an opening of the developer container, for carrying the developer; an elastic blade for forming a nip between the developer carrying member to regulate an amount of the developer on the developer carrying member; wherein a distance between the nip and an outwardly extending upstream end of the elastic blade with respect to a movement direction of the developer carrying member continuously increases from a longitudinal end of the elastic blade toward longitudinally central portion.

Abstract: A developer regulating member includes a thin plate having a spring property and a polyamide-containing rubber layer disposed on the thin plate. The polyamide-containing rubber layer contains a polyamide having the Shore D hardness between 25 and 65 both inclusive. A developing apparatus includes a developer container for containing a monocomponent developer of negative charging property, a developer carrying member provided in an opening portion of the developer container, for carrying the developer, and a regulating member for forming a nip together with the developer carrying member and regulating a thickness of a developer layer on the developer carrying member. A surface of the regulating member forming the nip is comprised of a polyamide-containing rubber layer containing a polyamide having the Shore D hardness between 25 and 65 both inclusive.

Abstract: A color image processing apparatus includes arranging means for arranging intervals between dot positions on a scanning line at which dots are formed, and shifting means for shifting the dot positions on the scanning line by a shifting amount. At least one of the intervals and the shifting amount for a first color component are different from an interval and a shifting amount of a second color component. The processing apparatus also includes control means for controlling the arranging means and the shifting means so that n (n.gtoreq.3) adjacent dot positions at which the first color component and the second color component overlap correspond to vertices of a substantially regular polygon having n vertices.

Abstract: A developing apparatus includes a developer carrying member, disposed opposed to an image bearing member, for carrying a developer; a developing bias voltage applying source for applying a developing bias voltage having an oscillating component to the developer carrying member to develop an electrostatic latent image formed on the image bearing member; wherein10.0.ltoreq.T11/(T11+T12).times.100.ltoreq.90.0,where T11 is a time period of a first step in which an electric field is formed in a direction for directing the developer from the developer carrying member toward the image bearing member in one cycle of the oscillating component of the developing bias voltage applied by the developing bias application source, and T12 is a time period of a third step between the first step and a second step in which an electric field is formed in a direction for directing the developer from the image bearing member to the developer carrying member, and T11/(T11+T12) is an inclination of the developing bias voltage.

Abstract: An image forming apparatus includes an input unit for inputting image data and a converter for converting the input image data into dot information. An image forming circuit controls a scan optical system on the basis of the dot information to form an image. The converter converts the image data into dot information having a screen angle by repeatedly using a predetermined threshold matrix so that the dot information appears preferentially in a sub-scan direction, perpendicular to the main-scan direction of the scan optical system. In the threshold matrix, threshold values are arranged so that their levels increase preferentially in the sub-scan direction.

Abstract: An image forming apparatus includes an image bearing member for bearing an electrostatic latent image; developer carrying member for carrying a developer comprising toner particles; a voltage source for applying to the developer carrying member an oscillating voltage having a predetermined frequency; wherein the following is satisfied:.vertline.Vpp-2Vcont.vertline./16Vf.sup.2 <d.sup.2 /.vertline.Q.vertline.where Vpp (V) is a peak-to-peak voltage of the oscillating voltage, Vf (Hz) is the frequency of the oscillating voltage, Vcont (V) is a potential difference between a voltage of a DC component of the oscillating voltage and a potential of an image portion on the image bearing member when a maximum image density is provided, Q (c/kg) is an average triboelectric charge amount of the toner particles, and d (m) is a gap between the image bearing member and the developer carrying member.

Abstract: A toner for electrophotography, comprising toner particles and an additive, is obtained by mixing toners A and B together which are obtained by respectively adding the additive to each of at least two toner particle groups (a) and (b) having different particle size distributions. The average particle size of the toner particle group (a) is smaller than that of the toner particle group (b), and the amount of additive in the toner A is larger than that in the toner B. The toner reduces the differences in development conditions between different particle sizes due to broadening of toner particle size distribution, thereby enabling a stable image quality to be obtained which maintains a high image density for an extended period of time and is relatively free from fog generation in non-image portions.

Abstract: A color image processing apparatus for sequentially inputting image data which corresponds to each of a plurality of color components in units of pixels of a predetermined quantity, delaying, with respect to a reference phase, at least the first color component or the last color component and sequentially forming image in the units of pixels of a predetermined quantity in accordance with the delay.

Abstract: An image forming apparatus includes an image bearing member; a latent image forming device for forming on the image bearing member a dot distribution electrostatic latent image in accordance with image signals corresponding to an object image; a developing device for developing the latent image formed on the image bearing member by the latent image forming device, in a developing station and by a developer containing toner and magnetic carrier; wherein the developing device includes a developer carrying member for carrying and conveying the developer to the developing station, and a magnetic field generating device provided within the developer carrying member, for forming a magnetic brush of the developer and contacting the magnetic brush to the image bearing member; and wherein a degree .sigma.d (emu/cm.sup.

Abstract: An image forming apparatus includes an image bearing member for bearing an electrostatic latent image; developer carrying member for carrying a developer comprising toner particles; a voltage source for applying to the developer carrying member an oscillating voltage having a predetermined frequency; wherein the following is satisfied:.vertline.Vpp-2Vcont.vertline./16Vf.sup.2 <d.sup.2 /.vertline.Q.vertline.where Vpp (V) is a peak-to-peak voltage of the oscillating voltage, Vf (Hz) is the frequency of the oscillating voltage, Vcont (V) is a potential difference between a voltage of a DC component of the oscillating voltage and a potential of an image portion on the image bearing member when a maximum image density is provided, Q (c/kg) is an average triboelectric charge amount of the toner particles, and d (m) is a gap between the image bearing member and the developer carrying member.

Abstract: An image processing apparatus binarizes input multi-level pixel data by changing the same either to the minimum density data corresponding to white or to a minimum reproducible density data corresponding to the minimum density level reproducible by an image forming apparatus such as a printer, when the density defined by the input multi-level pixel data is of such a low level that it cannot be reproduced by the image forming apparatus. Error incurred by the binarization is reflected in the succeeding binarizing process so that the density of the whole image is preserved, whereby an image with a highlight portion can be recorded with reduced degradation of the image quality at the highlight portion.

Abstract: A color electrophotographic apparatus includes a photosensitive member movable along an endless path; a charger for charging the photosensitive member; a scanning optical system for scanning the photosensitive member having been charged by the charger with information light responsive to color signals; a controller for controlling an exposure amount of the photosensitive member by the scanning optical system; a transfer device for simultaneously transferring toner images formed superposedly on the photosensitive member; wherein the controller controls the optical scanning system in consideration of transmissivity of the light through the toner.

Abstract: An image forming apparatus wherein a laser beam produced by a laser source is imaged through an imaging optical system on an image bearing member as a beam spot. The beam spot scans the image bearing member in a main scan direction. The laser source is rendered on and off to form an image with picture elements. The laser driving pulse width per picture element is changed in accordance with the image density of the image to be formed, so that the tone gradation of the image is provided on the image bearing member in accordance with the pulse width. The size of the spot measured in the main scan direction (1/e.sup.2 diameter) is not more than 0.7 times of the size of the picture element measured in the main scan direction.

Abstract: An image forming apparatus has exposure unit for emitting light modified in accordance with image information, the light quantity of said exposure unit being variable, image forming unit for forming image on a photosensitive medium in accordance with light emitted from the exposure unit, detector for detecting the surface state of the photosensitive medium, and controller for optimizing the light quantity of the exposure unit in accordance with the output of the detecting unit. The control unit obtains a potential versus image information variation characteristic of the photosensitive medium based on the output of the detecting unit and sets the light quantity of the exposure unit such that the characteristic approximate a straight line.

Abstract: In an image processing apparatus according to the present invention, the density of each pixel in a multi-level pixel block composed of a set of input multi-level pixel data is examined and a decision is made as to whether a pixel having a density which does not reach the minimum density below which printing is impossible, is present in the multi-level pixel block. If a pixel having a density below the minimum density is detected, the density of this pixel is distributed to another pixel position in the multi-level pixel block. In this manner, the number of pixels with a density which does not reach the minimum density below which printing is impossible, is reduced within each multi-level pixel block.

Abstract: An image forming apparatus for forming a color image from image data on an image having a plurality of colors. Density conversion information is stored with respect to pixel blocks having a predetermined phase and a predetermined configuration, which blocks are provided for each color. Pixel density values of image data items corresponding to each of the density conversion blocks are successively compared with a predetermined threshold value, and the compared image data item is converted according to the density conversion information if it is the case that pixel density is less than predetermined threshold value is satisfied, thereby limiting changes in color tones at a highlighted portion of the image and stabilizing the color tones.