Abstract: An image can be outputted with a high sharpness without deteriorating a resolution. In order to output an image of a high picture quality while suppressing the occurrence of a moire, an exposure amount is modulated in accordance with pixel density information of the image divided into pixels of a predetermined size by an exposure amount modulating unit in a light scanning unit, thereby expressing an image dark/light state. In this case, in a highlight density region in which a pixel density is equal to or less than 1/3 of the maximum image density, the density data of two adjoining pixels is modulated by one pixel and the other pixel is not recorded. In a density region in which the image density lies within a range from 1/3 to 1/2 of the maximum image density, a part of the density data of one of the two adjoining pixels is transposed to the other pixel. In a density region in which the image density is equal to or larger than 1/2 of the maximum density, the pixel transposition is not performed.

Abstract: An image having suitable color-tone and density is formed on a recording medium so that a full-color image of an excellent color-tone depending on a OHP can be projected, wherein a CCD separates colors of an original image to read it for converting into a RGB digital signal by an A/D conversion circuit, the process corresponding to a required image signal forming condition is executed by image process means for the digital signal to generate an image signal for outputting it to an LD driver, and a full-color image forming apparatus for forming a color image on a recording medium utilizing plural kinds of color materials based on the image signal comprises the image processing means for executing a gradation conversion process for the signals of C, M and Y in a LUT 1 circuit and executing a different gradation conversion process for a black signal Bk in a LUT 2 circuit different from a LUT 1 circuit.

Abstract: An image processing apparatus in which a density band separating circuit separates an image signal having different density levels into two areas as determined by a threshold density level. Image signals above the threshold are defined as shadow section density signals, and those below are defined as other density signals. The shadow section density signals are smoothed in a smoothing filter. The smoothed shadow section density signals and the other density signals are recombined by a look-up table process. The recombined density signals are pulse-width modulated to drive a printing device.

Abstract: When a gradation test pattern is read a predetermined period of time after the gradation test pattern was fixed, the correction amount can be controlled based on a stable image density, and an image with good gradation characteristics can be formed. A gradation test pattern including all color patterns is output in accordance with a gradation test pattern registered in a test pattern memory area, and at the same time, a timer is started. After an elapse of a predetermined period of time stored in a RAM, the output gradation test pattern is read by an original reader. On the basis of the read image density, a .gamma.-LUT is set.

Abstract: This invention has as its object to provide an image processing apparatus and method, which can obtain high image quality by adjusting an image forming parameter or parameters in consideration of a variation in image forming condition. In order to achieve the object, the gradation characteristics of an image to be recorded are adjusted on the basis of information obtained by forming a gradation characteristic adjustment test pattern on a recording medium, and reading the formed test pattern. Subsequently, the color reproduction characteristics of an image to be recorded are adjusted on the basis of information obtained by forming a color reproduction characteristic adjustment test pattern on a recording medium, and reading the formed test pattern.

Abstract: A method and apparatus for processing a medium on which an identification mark is formed using a plurality of recording materials having fluorescent characteristics in wavelength regions almost overlapping with each other and having maximum absorbing characteristics at different wavelengths. The method and apparatus include the features of detecting, on the medium, the identification mark which is comprised of the plurality of recording materials and controlling an operation of a processing apparatus in accordance with a result of the detecting of the identification mark.

Abstract: To properly cut light except for visible light and improve read precision, there is provided an image reading apparatus having a plurality of photoelectric conversion elements. The image reading apparatus includes an image information detecting unit in which the photoelectric conversion elements are arranged on a single chip, a first light-shielding unit, arranged near the photoelectric conversion elements, for transmitting specific visible light, and a second light-shielding unit, arranged near the photoelectric conversion elements at a position different from that of the first light-shielding unit, for partially shielding light except for the visible light.

Abstract: An image processor in which information or a pattern is added to input image data, with the added information or pattern having a resolution or density which is different from that of the input image data.

Abstract: An image forming apparatus includes an input unit for inputting image data representing an image, a synthesizing unit for synthesizing a predetermined information with the image represented by the image data, a forming unit for forming an image in accordance with the image data, a detecting unit for detecting a condition relating to an image forming by the forming unit, and a controlling unit for controlling the synthesis by the synthesizing unit based on the detection result of the detecting unit. An image forming method is also disclosed.

Abstract: A color image forming method and apparatus in which toner patterns, formed by toners of different colors, on an image bearing member, can be detected by a single sensor. Near-infrared light is emitted from an LED at each formation of a single-colored pattern on the photosensitive drum and the amount of near-infrared light reflected from the drum is detected by the sensor, for the purpose of effecting gradation control.

Abstract: An image reading apparatus includes, as an arrangement for discriminating a specific image with high precision, first illumination means for illuminating an object image so as to perform a normal reading operation, second illumination means for illuminating the object image with light having characteristics different from those of the light from the first illumination means so as to discriminate whether or not the object image is a specific image, and means for adjusting the quantity of light emitted from the first and second illumination means.

Abstract: A specified original that is not supposed to be copied is marked with a pattern that is formed by infrared reflected light. A copying apparatus includes a detecting unit for detecting the pattern and determines that an original is the specified original in accordance with the detection by the detecting unit. A copying operation is controlled in accordance with the determination of whether the original is the specified original that is not supposed to be copied.

Abstract: This invention has as its object to reduce the apparatus scale by simplifying the arrangement of an image reading apparatus for radiating light including both visible and non-visible components, and detecting light obtained from a predetermined image, and provides an image reading apparatus which has illumination means for simultaneously radiating both light including a visible component and light including a non-visible component, and detection means for detecting light obtained from a predetermined image in accordance with the light radiated from the illumination means, including filter means which can be switched in accordance with whether the visible or non-visible component is radiated from the illumination means onto the predetermined image, and control means for controlling a switching operation of the filter means.

Abstract: An image forming apparatus for forming an over laid image on a transfer material includes an electrophotographic photosensitive member movable along an endless path, a latent image forming device for forming an electrostatic latent image on the photosensitive member, a developing device for developing the electrostatic latent image with toner, and a transfer device for transferring the toner image onto the transfer material. The latent image forming device includes a controller for changing a latent image forming condition go as to reduce a potential difference between a latent image potential formed in a first rotation of the photosensitive drum at the start of image forming operation and a latent image potential in a subsequent rotation, and a latent image to be developed is formed from the first rotation without pre-rotation effected until the charge potential of the photosensitive member is stabilized.

Abstract: An image forming system includes a generator for generating an image signal representing a predetermined test image having a plurality of tone levels, an image forming device for forming the predetermined test image on a recording medium based on the signal, a first measuring device for measuring density levels of the formed predetermined test image, corresponding to each of the plurality of tone levels of the image signal, a controller for determining characteristics of a change of density levels in the predetermined test image to a change of tone levels in the image signal based on a plurality of density levels measured by the first measuring device, and for making a conversion data table for converting tone levels of an input image signal in accordance with the characteristics, a designator for generating instructions for designation a correction of the conversion data table, a transferring device for transferring the image formed on the recording medium to a recording sheet, a second measuring device for

Abstract: An object of the present invention is the forming over a long period of time of images that have a desirable density and gradation.According to the present invention, an image pattern, at the maximum image density, is formed on a photosensitive drum and read by a detection unit that incorporates an LED and a photosensor. Based on the read-out data, an image forming condition is corrected so that a maximum density is slightly higher than a target maximum density. Further, an image pattern that shows density gradations is formed on the photosensitive drum, and is read by the detection unit. Based on the read-out data, the image forming condition is corrected so that the gradation characteristic is stable.

Abstract: An image processing apparatus for processing gradation images which includes a pattern forming circuit for forming a predetermined pattern on a medium. A detecting device detects the predetermined pattern on the medium and generates a detection signal. A processing circuit processes the input image signal in accordance with the detection signal and outputs a reproduction signal. A setting device manually sets an image signal processing condition of the processing circuit, thereby accomplishing optimization of the image processing.

Abstract: An image forming apparatus performs excellent gradation control in a dense area in which gradation characteristics are non-linear. The image forming apparatus has a pattern forming unit which forms a gradation pattern on a recording member, and a read unit which reads the gradation pattern formed by the pattern forming unit. An adjusting unit adjusts image forming conditions on the basis of the gradation pattern read by the pattern read unit. In a density area in which gradation characteristics are non-linear, the number of steps of the gradation pattern is set to be larger than that in another density area.

Abstract: When a predetermined pattern (e.g. a pattern indicating the serial number of a copying machine) is added on an image formed on a recording paper, the image formation apparatus suppresses the appearance of fog by the addition of a predetermined pattern in the vicinity of the image. More particularly, a control circuit, which inputs and processes an image signal, estimates the leading and ending edge positions of the recording paper with respect to the transferring direction. The edge which is perpendicular to the transferring direction of the recording paper is determined based on a signal obtained from an ITOP generation circuit and a BD detector. Accordingly, an effective area for image formation on the recording paper is obtained and a modulation amount for adding the predetermined pattern is controlled in accordance with the position on the recording paper at which the predetermined pattern is added.

Abstract: An image forming apparatus includes an input unit for inputting image data representing an image, a synthesizing unit for synthesizing a predetermined information with the image represented by the image data, a forming unit for forming an image in accordance with the image data, a detecting unit for detecting a condition relating to an image forming by the forming unit, and a controlling unit for controlling the synthesis by the synthesizing unit based on the detection result of the detecting unit. An image forming method is also disclosed.