Abstract: In an image forming apparatus having an LED print head according to the present invention, the cycle period of a lighting reference clock signal is variably set according to the tone level of image data so as to variably set the lighting period of an LED according to the tone level of the image data. This makes it possible to provide a linear characteristic relationship between the image data and the tone level of a formed toner image for improvement of an image quality.

Abstract: The invention is directed to compensating for imaging aberrations that result from repeated passes by an imaging laser array. The aberrations may result from swath lines formed by thermal heating and from the ruling and screen angle of the image. The techniques described herein reduce the undesirable aberrations in thermal laser generated images by breaking up and/or reducing the swath lines. In general, the techniques provide for overlapping swaths and providing masking for one or both passes that print the overlapped region.

Abstract: Apparatus and methods for test printing are described for computer printer or other printers, including multi-pass engines or other engines. A test pattern may be printed on a non-consumable material preferably inside the printer and is made viewable by an onlooker either by the non-consumable being stationary and in view of a window/door, or moveable to the window/door after the test pattern is printed. Preferably, the test pattern is printed on an electrophotographic print engine intermediate transfer, so that printing quality produced by the entire width of the photoconductor and transfer member is diagnosed. By viewing the test pattern image, a user may see whether all toners or inks are printing properly, preferably whether all are printing without significant defects and are all aligned. Once the temporary test pattern is viewed or when a new print job is requested, the system cleans the test pattern off of the transfer member.

Abstract: A method for driving an optical write device, in which a time for formation of a pixel is divided into a plurality of periods, and tone level control based on multi-tone image, data is performed in each of the periods. For example, the time for formation of a pixel is divided by applying a train of pulses with widths weighted in the ratio of 4:2.1, and in each duration of the pulses, a clock signal for 64 tone levels is given.

Abstract: The method is for setting the line width of recorded image lines of a focused image beam in an exposer. The exposure point has a diameter and an area with a non-uniformly distributed the power density. The recording material has a first exposure threshold and is exposed with an energy density near a second exposure threshold that is substantially higher than the first exposure threshold. The recording material can be a photopolymer printing plate. The line width of the recorded image lines is determined from the distribution of the power density over the area of the exposure point by integrating the time variation of the power density resulting from the exposure speed of the laser beam. The line width is set, by changing the diameter of the exposure point and/or by the laser power, such that the line width is substantially equal to the line spacing.

Abstract: An apparatus for correcting beam-to-beam spacing error on an image plane of a photoreceptor includes a controller which generates beam-to-beam spacing error corrections signals, a plurality of optical elements, each of which is adjustable and responsive to beam-to-beam spacing error correction signal and a gray level measurement device. The controller performs the beam-to-beam spacing error correction analysis, determining whether or not a correction is necessary, and if so, which optical element to adjust and the magnitude of adjustment. Enhanced toner area coverage sensors are used to detect the gray level of a toned area of raster scan line patterns at various locations across the photoreceptor image plane. By repeatedly evaluating the beam-to-beam spacing error during operation, the apparatus of the invention is able to correct beam-to-beam spacing errors that may develop during operation and does not permit residual errors to persist even after an initial correction has been implemented.

Abstract: A dot-matrix image-forming device such as an electrophotographic printer alters the size of a dot according to the surrounding dot pattern, thereby compensating for the tendency of isolated dots or small groups of dots to be undersized due to characteristics of the image formation process. Alternatively, the device may add dots to or delete dots from a contiguous group of dots to achieve substantially the same effect. Preferably, the device both adds or deletes dots and alters the dot size. This compensation scheme enables the total area occupied by dots in a given image region to be proportional to the number of dots in the region, regardless of the dot density and arrangement in the region.

Abstract: The invention is directed to compensating for imaging aberrations that result from repeated passes by an imaging laser array. The techniques described herein reduce the undesirable aberrations. In general, the techniques provide for printing a first line of image data and a set of contiguous lines as a function of the image data and a first mask. On a subsequent pass, these lines are overlapped. The line that overlaps the first line prints the image data again, but masked. The lines that overlap the contiguous lines print the image data normally.

Abstract: An image recording method comprising: forming a latent image on a photothermographic imaging material by exposing a light beam from a light source thereto; and forming a visible image on the photothermographic imaging material on which the latent image is formed by thermally developing it. A wavelength characteristic of the light beam from the light source is selected on a basis of a spectral sensitivity characteristic of the photothermographic imaging material so that a first sensitivity variation of at least one of the thermally developed photothermographic imaging material and the exposed photothermographic imaging material which is before being thermally developed, the first sensitivity variation being caused by a temperature variation, and a second sensitivity variation of the photothermographic imaging material according to a wavelength variation of the light beam from the light source caused by the temperature variation are offset.

Abstract: An information recording method for recording desired information, wherein a control circuit (150) identifies a characteristic of light corresponding to information to be recorded, in accordance with table data stored in a table memory (151), indicating a corresponding relationship between the information to be recorded and the wavelength of the light and selects a light emitting material which emits the identified characteristic of the light in response to energy (electricity or light) supplied thereto, and a recording head (110) forms a light emitting element by supplying the light emitting material on a substrate (10) of a recording medium. Furthermore, energy is supplied to the recording medium on which the information is written so that the light emitting material emits light, the characteristic of the light is identified and the information is reproduced in accordance with the identified characteristic. The security of the information is enhanced with a new and easy method of information recording.

Abstract: It is the purpose of the present invention to provide an image recording method and image recording apparatus for performing high-density recording without degrading the resolution. A desired image is recorded on a recording medium by exposing the image on the recording medium while moving the recording medium in the main scan direction where a toner layer of a transfer sheet is overlaid on an image reception layer of an image reception sheet as well as moving a plurality of laser beam spots arranged on the recording medium in the sub-scan direction orthogonal to the main scan direction. In this practice, a recording process on the transfer sheet is repeated a plurality of times to record a same image repeatedly with transfer sheets replaced after the transfer sheet has been exposed.

Abstract: An image forming apparatus lessens the sense of incongruity between CMY mixture gray and K monochrome gray so as to achieve an easy color adjustment. An adjustment sheet is printed by the image forming apparatus. The adjustment sheet has a reference pattern and a plurality of test patterns. The reference pattern indicates a reference concentration of gray and the test patterns indicates concentrations of gray within a predetermined concentration range including the reference concentration. The gray of the test patterns is a mixture of cyan, magenta, yellow and black. The gray of the reference pattern is monochromatic black. The test patterns are visually compared with the reference pattern so as to select one of the test patterns of which concentration matches the concentration of the reference pattern. The concentration of gray is adjusted in accordance with the concentration of the selected one of test patterns.

Abstract: A reactive toner that is energy-activated is printed by means of an electrographic device such as a laser printer. The reactive toner is printed onto a substrate. Toner components that cross-link and bond the printed toner permanently onto the substrate, or another substrate through a transfer process, are activated by the application of energy to react after printing. Reaction of the energy-activated components may be inhibited with blocking or protecting agents. The image is permanently bonded onto the substrate when the protection provided by the protecting agents is removed by the application of energy to the printed toner. The toner may comprise energy-activated components, colorants, color enhancing polymeric materials, binder resins, internal and external additives such as waxes and charge control agents.

Abstract: Apparatus and methods for test printing are described for computer printer or other printers, including multi-pass engines or other engines. A test pattern may be printed on a non-consumable material preferably inside the printer and is made viewable by an onlooker either by the non-consumable being stationary and in view of a window/door, or moveable to the window/door after the test pattern is printed. Preferably, the test pattern is printed on an electrophotographic print engine intermediate transfer, so that printing quality produced by the entire width of the photoconductor and transfer member is diagnosed. By viewing the test pattern image, a user may see whether all toners or inks are printing properly, preferably whether all are printing without significant defects and are all aligned. Once the temporary test pattern is viewed or when a new print job is requested, the system cleans the test pattern off of the transfer member.

Abstract: In an optical printing apparatus with employment of a low-cost arrangement, a high image quality recording operation is realized.

Abstract: A heat developing apparatus for developing a heat-processable photo-sensitive material having a supply unit provided with a loading section for loading the heat-processable photo-sensitive material, an exposure unit for forming a latent image based on an image signal or on a predetermined signal for density measurement, a developing unit for heat development, a device for gaining density information of the heat-processable photo-sensitive material developed, and a controller for conducting a correction for a density of the heat-processable photo-sensitive material based on a desired density and the density information, by controlling at least one of the exposure unit and the developing unit, wherein, the controller conducts the correction according to the density information when a predetermined condition is satisfied after a new package incorporating the heat-processable photo-sensitive material has been loaded on the loading section.

Abstract: An object of the present invention is to provide a laser drawing apparatus wherewith it is possible to draw fine patterns at high speed with uniform fineness. In order to achieve that object, in the present invention, drawing is performed at high speed by moving a laser spot in the radial direction while turning a blank disk coated with a photosensitive material mounted on a turntable. A discretionary pattern 203 within a fan-shaped area having the turning center 201 of the blank disk as its center is divided into dots of the same size such as the small areas 209, pattern drawing is performed using such dots as units to be drawn by the laser spot, and the fineness of the pattern shape is enhanced.

Abstract: In an optical printing apparatus, an image having a high image quality is desirably produced under stable condition, even when variations occur and exposure conditions are different from each other, which are caused by differences in response speeds of a light source and a liquid crystal shutter element, and also by differences in element driving conditions. The optical printing apparatus is arranged by including: image data input for inputting image data; reference level generator producing a reference level; comparator for comparing multi-value data outputted from the image data input with the reference level so as to convert the multi-value data into binary data; data transferring element for transferring the binary data outputted from the comparator as head data to the print head; latch controller for latching data of the print data; and strobe controller capable of causing the print head to expose the light therefrom.

Abstract: A method of tuning a printer by printing a pattern, which beats against a component within the printer comprises designing a first pattern, which has a spatial frequency, which is different from a first component spatial frequency. A first pattern is printed and banding is measured. To minimize banding a characteristic of the first component is adjusted.

Abstract: A pulse width modulation circuit is provided with a signal generating circuit generating a reference clock signal and a predetermined signal which is approximately inversely proportional to a digital data input signal, a delay quantity generating circuit delaying the reference clock signal by a desired phase delay to output a pulse signal, based on the predetermined signal from the signal generating circuit, a delay quantity controller controlling a delay quantity of the delay quantity generating circuit, and a modulated signal generator generating a modulated signal which is pulse-width-modulated based on the pulse signal from the delay quantity generating circuit and the reference clock signal.

Abstract: Adjustment of correction data for the respective LEDs at the end of manufacture of a print head is performed by transferring provisional correction data from a manufacturing device to an LED driver, directly, i.e., without once being stored in a storage circuit 10c in the print head, and measuring the amounts of light from the LEDs and varying the correction data, and repeating such an operation until the correction data is optimized. The optimized correction data as well as the strobe time data determined from the measured average power are written in the storage circuit 10c. During use of the printer, the data stored in the storage circuit 10c is used for correction of the data and determination of the strobe time.

Abstract: Disclosed is a method for measuring light quantities emitted from an array of light shutter elements aligned in a main scan direction. The method measures the light quantities by scanning and sensing a recording paper on which an image is formed by the light shutter elements. The scan direction is orthogonal to a direction in the image corresponding to the main scan direction of the array.

Abstract: An image recording method comprises the steps of attaching recording paper on an outer peripheral surface of a recording drum, attaching an image receiving sheet having an image receiving layer on the recording paper to transfer the image receiving layer thereon, attaching a toner sheet on the image recording sheet, and transferring toner of the toner sheet onto the image receiving layer in accordance with recording data.

Abstract: In an image forming apparatus having an LED print head according to the present invention, the cycle period of a lighting reference clock signal is variably set according to the tone level of image data so as to variably set the lighting period of an LED according to the tone level of the image data. This makes it possible to provide a linear characteristic relationship between the image data and the tone level of a formed toner image for improvement of an image quality.

Abstract: The present invention relates to an image forming apparatus in which an electrostatic latent image is formed on an electrophotographic photosensitive member with digital light, and electrostatically developed with a developer to form a developed image. The apparatus has an exposure device for normally increasing the reflection density only in a specified region on the photosensitive member in a white image portion where no image is basically formed, in the horizontal scanning direction of the digital light. For example, a small amount of developer is supplied to either end of the photosensitive member having the tendency that the amount of the developer supplied is small, thereby preventing the occurrence of image flow at either end.

Abstract: An apparatus for registering a laser patterned image on a circuit board has a controller operating laser beam source, modulating and scanning components capable of generating, modulating and scanning one or more laser beams across a circuit board held on a support. The controller provides a data signal to the components, the data signal comprising a grayscale image bitmap comprising image pixels having grayscale levels that correspond to fractional beam intensities.

Abstract: Disclosed is a method for enhancing print quality by adjusting a print density of a printer according to changes in the environment. Threshold tables having different threshold values corresponding to different environments of a printer engine are stored in the printer and the printer itself can perform a halftone process. According to the method, print data to be printed are first received and stored when a print operation command is received. Then, present environmental state information is received from the printer engine. Corresponding to the present environmental state information, a threshold table is selected among the threshold tables. Thereafter, the lightness of the print data is determined through the selected threshold table and the halftone process is performed. Then, the print data that is image-processed through the halftone process is transmitted to the printer engine to be printed.

Abstract: A method that involves sweeping multiple beams for a plurality of sweeps. The multiple beams are modulated for the plurality of sweeps according to a test pattern. The test pattern has an associated vernier period and the vernier period corresponds to a wavelength. The wavelength is perceptible to the human eye. An apparatus having a printhead configured to produce multiple beams where the multiple beams are configured to be modulated according to a stored test pattern. The test pattern has an associated vernier period and the vernier period corresponds to a wavelength. The wavelength is perceptible to the human eye.

Abstract: A method for improving exposure resolution that includes several steps. A high gray scale resolution image is analyzed and a determination is made of a media plane (331) exposure gray scale resolution requirement. Exposure time and an exposure intensity is determined for each of the low gray scale resolution intermediate images. A number of low gray scale resolution intermediate images (332) are required to provide the media plane exposure resolution; and an exposure time and exposure intensity (333) for each of the low resolution intermediate images is determined. An image content for each of the low gray scale resolution intermediate images is determined (334) and each of the low resolution intermediate images is printed (335) at the exposure time and the exposure intensity.

Abstract: In an image recording apparatus provided with a recording head and a conveyor for relatively moving the recording head and an image recording medium, an image composed of a large number of pixels is recorded by plural recording elements of the recording head on the image recording medium relatively moved by the conveyor. Each recording element of the recording head is controlled to conduct turning on or off plural times (N times) so that one pixel is recorded by plural recording periods of each recording element, and a time length T(m) of each recording period is not increased monotonously or is not decreased monotonously with respect to recording sequential order “m” of each recording period in recording of each pixel, wherein “m” is an integer not less than 0 and not more than N−1. The time length of each recording period is obtained by adding one or two coefficients to a binary-weighted value.

Abstract: An optical write head which drives a plurality of light shutter elements arranged in a main scanning direction individually to write a multi-tone image on a recording medium. Prior to the image writing, while the light shutter elements are driven for reproduction of tone levels of 0, 48, 160 and 240, the quantities of light outputted from each of the elements are measured with a sensor, and from the measured values, an approximate expression indicating the output characteristic of each of the elements is calculated. The difference between the recording medium and the sensor in spectral sensitivity is made up, for example, by changing the intensity of light of each of the three primary colors emitted from a lamp by switching the voltage applied to the lamp between at the time of measurement and at the time of exposure or by changing the sensitivity of the sensor in receiving each of the three primary colors by switching the accelerating voltage applied to the sensor.

Abstract: An optical printing device for exposing a photosensitive recording medium to form a grayscale image includes a print head having n rows of recording elements capable of exposure of different colors and aligned in a direction of advancement of the photosensitive recording medium, where n is an integer more than 1, the n rows of recording elements being spaced substantially a multiple of L×(m+k/n) apart in the direction of advancement of the photosensitive recording medium, where L denotes a distance between the centers of recording pixels according to the desired resolution of a recorded image, m is an integer of 1 or more, and k is an integer of 1 or more and less than n. The optical printing device also includes a head driver for driving the print head. Light from the print head is selectively exposed on the photosensitive recording medium to form the grayscale image.

Abstract: An image forming apparatus that increases the relative resolution of a small image to be output for recording. When the image forming apparatus is used for copying an image of an original document, when the size of an image to be output is not greater than a predetermined size, a CPU controls a resolution switching unit for increasing the resolution to form an image with increased resolution.

Abstract: A non-impact printer has a print data correction circuit for providing a print data correction processing for video signals transmitted from a printing control unit to produce correction output data or patterns for printing on basic raster lines and other correction output data or patterns for printing on sub-raster lines. Those correction output data or patterns are supplied to the print head in the form of a real printing data signal.

Abstract: A method is disclosed for testing a light emission condition of an exposing head of a type including a plurality of luminous elements arranged along a main scanning direction for forming a linear dot pattern on a print paper. The exposing head is movable relative to the print paper in a sub scanning direction. The emission amounts of the respective luminous elements are compared to each other, based on the densities of respective dots obtained by exposure on the print paper. For allowing more accurate grasping of the light emission of each luminous element, testing target dots are formed by driving luminous elements selected as target elements which are not adjacent each other in the main scanning direction. Further, background dots are formed in the peripheries of the target dots so that the peripheries are completely filled with the background dots having a density higher than that of the target dots.

Abstract: The density correction method according to the present invention includes recording an image on said recording medium at a predetermined halftone density, measuring record density of a result of recording of the halftone density by a densitometer, raising the relative speed between the recording head and the recording medium when the measured record density is higher than the required density and lowering the relative speed when the measured record density is lower than the required density, recording an image on said recording medium at two or more halftone densities after a set value of the relative speed has been changed, and updating a density conversion table for converting input data in such a manner that the record density of a result of recording substantially coincides with the predetermined density.

Abstract: A current control circuit including at least one bit corrector for performing full-scale activation or deactivation of a voltage to gate terminals of output units according n-bit correction data, and at least one digital to analog converter for adjusting a voltage to be applied between drain and source terminals of transistors of the output units. This circuit is used for the bit correction and gradation control.

Abstract: An image data control unit for an SLM-based photofinishing system. The control unit is typically used with a photofinishing system in which the SLM provides an exposure region that is smaller than the image to be printed or otherwise produced. Thus, the output image is in motion relative to the SLM, such as by moving the photographic medium under the SLM. To meet system throughput requirements, such systems use an exposure algorithm that exposes each line of the output image with multiple rows of the SLM. The control unit implements the exposure algorithm by reformatting source image data and loading the SLM with SLM settings. It synchronizes these functions to the motion of the photographic medium upon with the image is printed.

Abstract: An image reading apparatus includes: a size detector for detecting a first size of a first image recorded on an original; an input device for inputting a second size of a second image to be recorded on a recording medium by an image recording apparatus; a determining device for determining a reading condition to read the first image according to the first and second sizes; and a reading device for reading the first image according to the reading condition to obtain information of the first image.

Abstract: Bit data of a received video signal is partially converted into a first signal representing a data sequence corresponding to the resolution of an LED head. The first signal is transmitted to the LED head in the form of a real printing data signal that is to be printed on a basic raster line in synchronism with a line timing signal. The remaining bit data of the received video signal, which are not converted into the first signal, are converted into a second signal representing another data sequence, and then stored in a line buffer. The second signal stored in the line buffer is transmitted to the LED head in the form of a real printing data signal that is to be printed on an additional raster line in synchronism with an additional line timing signal. The LED head drive energy with which the basic raster lines are printed and another LED head drive energy with which the additional raster lines are printed are set independently of each other. The LED head may be provided with such a resolution function.

Abstract: The improved image recording apparatus that performs image recording on a recording material to output a print with a record of a visible image includes an outputting device of a print having printed thereon a minimum density in the recording material, a measurement device for measuring the minimum density that has been recorded on the print, and a control device by which tones to be recorded are controlled in accordance with the minimum density measured by the measurement device. The image recording apparatus that uses various recording materials including light-sensitive materials and thermal recording materials and which, in spite of the fluctuation in the fog density of a particular recording material or the difference in characteristics between production lots and other identifications of the recording material, is capable of consistent recording of high-quality images that assure satisfactory tone representation over the entire density range including low densities.

Abstract: Image patterns formed on a sheet of paper changes in correspondence with an input image density. As the input density increases, the image patterns change from the state of FIG. 6(a) through the state of FIG. 6(b)-6(g) to the state of FIG. 6(h). As apparent from the drawings, as the input density increases, the linear patterns will extend in a direction parallel to the sheet conveying direction A. Even when mechanical oscillation occurs in the sheet conveying direction A, no changes in tone will appear. When the input density further increases from the state of FIG. 6(d), the linear patterns will grow both in leftward and rightward directions. Because each dither matrix is elongated in the sheet conveying direction A, the linear patterns will grow in the leftward and rightward directions only after the input density increases to some great value. It is therefore possible to effectively prevent occurrence of jitter.

Abstract: An image forming apparatus having a colorimeter for measuring density or color of an image, and capable of carrying out calibration with high accuracy. In the image forming apparatus, a test image, and a first reference line and a second reference line for defining a position of the test image on an image receiving paper, are exposed and formed on a photosensitive material. The first reference line and the second reference line formed on the image receiving paper are detected by a reflective photosensor so that a position at which the test image is formed on the image receiving paper is automatically determined. As a result, test image data, which is stored in advance in the image receiving apparatus, and a measurement position, at which measurement is carried out by a colorimetry apparatus, can be made to correspond to each other accurately.

Abstract: An image memory for storing input image data by plural lines, a horizontal scanning fringe correction exposure determining section for determining a fringe between close vertical lines in a horizontal scanning direction in the image data, a vertical scanning fringe correction exposure determining section for determining a fringe at the lower end of an image in a vertical scanning direction and a switch for selecting at least three laser drivers are provided.

Abstract: This is a halftone circuit which, in addition to the usual counting and addressing mechanisms, has control over the phase, angle and direction of the addressing circuitry of the array in memory so that regular dots, mirror images of dots and out-of-phase dots can be created from a single array, thus saving memory hardware. The mirror images can be made by counting rows in either direction, the angle can be varied by varying the number of pixels shifted between scans, and the phase can be varied by setting the starting point to any row and column. In this way, a single array can be used to create a number of dots.

Abstract: An image forming system includes an imaging data generator which generates a dot intensity data from each of a series of pixels contained in an input image, each pixel having bits indicative of an intensity of the pixel only, the imaging data generator including a plurality of discrimination patterns to detect the presence of a 1-pixel-thick vertical line or a multipixel-thick line edge in the input image. An optical writing unit modulates an emission power and/or an emission time of a laser diode by using the dot intensity data, and determines the emission power of the laser beam per dot based on the dot intensity data, so that the laser diode emits the laser beam to a photoconductive medium in accordance with the modulation data. When an intensity pattern related to a subject pixel and neighboring pixels thereof matches one of the discrimination patterns, the imaging data generator selects a corrected intensity value corresponding to the matched discrimination pattern as the dot intensity data.

Abstract: An optical printer apparatus exposes a sensitized sheet (500) to light from a light source (110), which is movable relatively to the sensitized sheet (500), with given timing in accordance with image data composed of pixels having a plurality of gradations that are linearly changeable from a minimum gradation of low color density to a maximum gradation of high color density. The distance for the exposure is adjusted for area gradation, whereby a gradated image is formed on the sensitized sheet (500). Further, change of the exposure distance, compared to change of the gradation, is not uniform throughout the range, and a non-linear relation is established between the changes.

Abstract: In a heat transfer recording apparatus for printing on photographic print paper using an ink film coated with sublimable ink, density unevenness that occurs at the edges of the wide printing paper is prevented by compensating density in the area that corresponds to the difference between wide print paper and narrow print paper.

Abstract: An image processing device capable of writing two lines at the same time and applicable to an apparatus using digital image data is disclosed. A data bus width control section controls the bus width of input data. A temporary storage temporarily stores data input thereto. A data control section controls the reading and writing of data out of the temporary storage. A two line section produces two lines for writing two lines of input data at the same time. A data converting section converts parallel data to serial data. A multilevel section transforms an input bilevel image to a multilevel image. A rate varying section varies the rate of multilevel data input thereto. A data selecting section selects processed multilevel image data. A register control section executes register control with at least data stored in a storage included in the multilevel section.

Abstract: A modulator drive function, for a hyperacuity laser printer that produces text and line art and halftones from numerically sampled input, incorporates device dependent characteristics, such as xerographic development and laser spot size, to position these edges precisely. The modulation drive function converts r,&thgr; channel coordinates to drive values for each scan within the span of its own channel pitch. A spline-based edge reproduction curve (ERC) compensates for slowscan phase errors and a temporal bias compensates for fastscan spot size. An electronic digital-to-analog converter, pulse width modulator or shift register can be used to control exposure.