Abstract: A laser imager autofocus apparatus, adapted to receive media with an image surface to be scanned, includes a laser and laser optics for producing a beam of light focused at an image plane. A photodiode is associated with the laser and adapted to produce a signal characteristic of the amount of light from the laser that is reflected from the image surface of received media onto the photodiode. Focus of the laser beam on the image surface is adjusted in response to the characteristic signal to maintain close association of the image surface of received media and the image plane of the laser and laser optics. The focus adjusting means may move one or more of the laser, the laser optics, or the image surface of received media. The laser source may be an array of plural laser sources in a line, and the plural laser sources may tilt relative to the image surface of received media.

Abstract: A color imaging apparatus, for forming a beam of light having three separate color components for image recording on a photosensitive member, includes red, green, and blue color component light channels, wherein the green light channel is formed by an LED of Gallium Nitride (GaN) material. In another similar color imaging apparatus the green light channel is formed by an LED of Indium Gallium Aluminum Phosphide (InGaAlP) material.

Abstract: An apparatus and method for providing contact between a donor sheet and a receptor sheet in a laser-induced thermal transfer printer make use of a support means for supporting a receptor sheet, means for mounting a donor sheet proximal to the receptor sheet over the support means, and means for applying tension to the donor sheet to draw the donor sheet into contact with the receptor sheet. The means for mounting the donor sheet and applying tension may be a clamp mechanism mounted on the support means. The clamp mechanism has a first clamp for holding a first end of the donor sheet and a second clamp for holding a second end of the donor sheet. The second clamp is movable relative to the first clamp to apply tension to the donor sheet, thereby drawing the donor sheet into contact with the receptor sheet.

Abstract: An electrophotographic printer includes a photoreceptor on a drum or belt, a laser beam that is reciprocally scanned thereacross, a beam detect signal circuit for generating a beam detect signal and an asynchronous clock oscillator for generating clock pulses. The printer also includes circuitry for generating a plurality of clock signals that are phase synchronized with the beam detect signal. The circuitry includes a tapped delay line for receiving the asynchronous clock pulses, each tap outputting a delayed clock pulse train. A register/selector circuit is coupled to the taps and is responsive to a transition of the beam detect signal for determining a tap which outputs a 0.degree. phase clock transition that is closely proximate to the beam detect signal. Phase delay logic provides signals indicative of which taps of the delay line circuit manifest clock pulse trains that are closest in time to leading and lagging edges of a 0.degree. phase clock pulse, respectively.

Abstract: A transfer printing medium that includes a carrier to which is applied a curable laser-transferrable ink having one or more layers. The transfer medium is capable of converting laser energy to heat. The ink includes: (a) at least one colorant; (b) at least one polymerization initiator; and (c) at least one curable prepolymer.

Abstract: There is provided an optical filtering system intended for use in a raster scanning arrangement for a document processing system. The document processing system includes a laser beam generating device providing a laser beam and a raster scanning device for transmitting the provided laser beam along a path. The optical filtering system includes a) an optical filter, disposed in the path, for reflecting the laser beam or permitting a portion of the laser beam to be transmitted therethrough, and b) a heating subsystem, thermally communicating with the optical filter, for maintaining the optical filter at a substantially fixed temperature.

Abstract: A device for producing a printing stencil, in particular a screen printing stencil, having a rotatably supported printing cylinder, a laser for generating a laser beam incident on the printing cylinder and capable of being displaced in the longitudinal direction of the printing cylinder, and focusing optics to focus the laser beam onto the surface of the printing cylinder. The focusing optics have at least one deflection mirror with an elastically deformable mirror diaphragm. At least one sensor is provided to measure a distance between itself and the surface of the printing stencil. An actuating signal generator generates an actuating signal as a function of the measured distance. Actuating devices set a curvature of the mirror diaphragm as a function of the actuating signal.

Abstract: A seven color separation process is provided in which, as well as the conventional Cyan, Magenta, Yellow and Black (CMYK) separations traditionally used in the four color printing process, additional Red, Green and Blue (RGB) separations are produced on a conventional scanner. The additional separations are produced using the Cyan, Magenta and Yellow channels of the scanner to measure Red, Green and Blue absorption characteristics of the source and to compensate the measured densities such that the separations represent a range of print densities from 0.0 D to 2.0 D corresponding to densities in the source in the range 1.0 D to 3.0 D. The transfer duration is also compensated for the compression which takes place in the preparation of the CMYK separations.

Abstract: An image writing apparatus has improved performance of image reproduction based on a multi-beam scanning optical system, in which the number of laser beams n and the spacing of scanning lines p meet the condition: 1/(n.multidot.p).gtoreq.4 line pairs per millimeter. The optical system is further designed such that the number of deflection planes q of the deflector, a natural number m, where the period of repetitive patterns of image in the slow scan direction is equal to p multiplied by m, and the least common multiple E of m and n, or the least common multiple G of m, n and q meet the condition:1/(E.multidot.p).gtoreq.4 or 1/(G.multidot.p).gtoreq.4 line pairs per millimeter.

Abstract: A method and apparatus for measuring colorimetric, gloss and registration data on a substrate exiting a printing machine. A detector using a series of red, green, and blue filters collects image data and maps the collected data to absolute color coordinates. The apparatus is factory calibrated to the specific colorants used in the printing machine. Gloss measurements are made using the same apparatus. Registration data between the various color separations is also obtained and feedback delivered to the various imaging modules. The detector allows on the fly data to be obtained and machine specific corrections to be made.

Abstract: A platesetting method and apparatus provides for dimensional and/or exposure sensitivity changes in a printing plate to be imaged in a platesetter. A condition sensor senses the temperature of the plate prior to exposure so that a control unit can adjust the control commands to the scanning exposure mechanism of the platesetter in order to compensate for any thermal expansion or exposure sensitivity shifts. An image to be recorded onto the plate material has a standard size at a standard plate material temperature. When the plate material is at a non-standard temperature, as determined by the thermal sensor, a program, stored in memory, calculates a new image size based on the non-standard temperature and the thermal characteristics of the plate material which are also stored in memory. The imagesetter electronic controller then exposes an image having a size which will be the standard size when the plate material returns to the standard temperature.

Abstract: A digital image forming apparatus is constructed to accurately detect period abnormality of a horizontal sync signal. In the apparatus, a sync signal generation portion outputs the horizontal sync signal by a received light signal from a light position detector. A sync signal abnormality monitor monitors whether a detected period of the sync signal is longer than a reference period, or it is normal. When the output signal of the sync signal is judged to be longer than the reference period, an abnormality detecting signal is supplied to a continuous turning-on portion. When the continuous turning-on portion receives the abnormality detecting signal, it issues an instruction to a synchronizing turning-on portion so that video data continues to be turned on, that is, turning-on signal is continuously outputted. Since a laser beam is continuously turned on by this instruction, the light position detector can certainly receive the laser beam.

Abstract: A raster output scanner (ROS) with a liquid crystal window located at the output of the ROS for correcting the nonuniformity of a light beam generated by the ROS is disclosed. Since the photocells in the liquid crystal can be controlled individually, a variable attenuation to match the curve of the intensity of the light beam, generated by the ROS, can be applied to the light beam. When the light beam with a variable intensity passes through the liquid crystal window of this invention, each cell applies an attenuation to offset the variation in intensity of the light received by that cell. Therefore, the light beam emerging from the liquid crystal window will have a uniform intensity regardless of the variation of the intensity generated by the ROS.

Abstract: An indication apparatus of paper amount within a paper cassette is provided. The paper amount varies due to consumption and has a corresponding variable weight. The cassette has a paper guiding apparatus for positioning the papers and the paper guiding apparatus has a bottom plate touching against a spring force. The cassette has a bottom which has a hook thereon. The indication apparatus comprises a cable having a first end connected to the hook and a second end. A shaft is connected to the cassette for supporting the cable and allowing the cable to slide on a path defined by the shaft. A glider with a predetermined weight is connected to the second end of the cable and has an indicator thereon. A plunger is positioned vertically and engages with the cassette for guiding the movement of the glider. The indicator indicates the amount of papers within the cassette in response to the variable weight of papers within the cassette, the spring force and the predetermined weight of the glider.

Abstract: A hyperacuity printing system for rendering image data on a recording medium, the image data being rendered as an array of pixels across the recording medium in a fastscan direction, and an orthogonal slowscan direction. The system includes a data source for supplying grayscale input image data and a scanning device for rendering grayscale output image data, the scanning device having a writing device for writing scan spots on the recording medium at a writing pitch in the slowscan direction and a writing pitch in the fastscan direction. The system also includes transformation circuitry for transforming the grayscale input image data into grayscale output image data, the transformation circuitry including a halftoner, a thresholder, and a selection device, where the selection device selects either the thresholder or the halftoner to provide the grayscale output image data.

Abstract: To print an image having a 300 x 600 dpi effective resolution with an ink jet printer that has a 300 dpi resolution, the method increases a resolution or density of the pixel image along the raster scan axis. The pixel image is thinned and raster scanned with the ink jet printer to visibly reproduce the pixel image at the 300 x 600 dpi resolution. The pixel image may be thinned based on a checkerboard pattern while maintaining and enhancing edges.

Abstract: Image forming apparatus and method for forming half tone images by pulse width modulating multi-valued image signals comprises first and second pattern signal generators which generate pattern signals each having the same period and a phase shifted from each other, first and second pulse width modulators for pulse width modulating said image signals using the first and second pattern signals, respectively, a selector for selecting either of the first and second pulse width modulated signals and a controller for controlling the selector to obtain a screen angle of 45.degree..Further, image forming apparatus and method which realizes a screen angle .theta. wherein tan .theta. is represented by a rational number.

Abstract: An apparatus includes a media handler which is capable of processing a supply of media sheets which can take the form of plates, aluminum or plastic used in lithographic printing presses or the like, or can be film which is advanced to a drum and scanned by a scanning process and thereafter removed from the drum surface by appropriate handling means.

Abstract: Information is recorded on a heat-sensitive recording material including a photo-thermo conversion agent which converts supplied light energy into heat energy, a developing agent and a color forming agent which is encapsuled in micro-capsules whose permeability to materials increases with increase in said heat energy and forms a color by reaction with the developing agent. The photo-thermo conversion agent is localized in and/or on the micro-capsules. The heat-sensitive recording material is heated by supplying the heat-sensitive recording material with heat energy less than energy necessary to cause the heat-sensitive recording material to form a color. A light beam modulated according to the information to be recorded is caused to scan the recording material.

Abstract: An electrophotographic image recording apparatus that forms an electrostatic latent image so that the uniformly charged surface of a photoreceptor is scanned for its exposure with a beam spot of a light beam generated according to image information, to discharge the surface of the photoreceptor up to a medium potential. The electrophotographic image recording apparatus includes a light beam generator capable of varying an amount of light beam and a light intensity distribution pattern of a beam spot on the surface of the photoreceptor, an intensity distribution pattern controller for controlling the light beam generator according to the image information of peripheral pixels, to vary the intensity distribution pattern of the beam spot on the surface of the photoreceptor, and a light beam output controller for controlling the light beam generator to put the exposure energy on pixels, exposed to the beam spots of intensity distribution patterns, at a predetermined value.