Abstract: A digital printing apparatus accepts image data in the form of PDL files, and also instructions, external to each PDL file, about shifting images formed at the PDL file to precise positions on a print sheet. The PDL file is interpreted to yield a raw bitmap, and then compressed according to a compression algorithm. The external shift instructions are then included in the compressed data as blank-line instructions which add a number of blank lines equal to a number of scan lines the image is desired to be shifted. The shifting is useful for accommodating bindings in the finished printed documents.

Abstract: When a thermal inkjet print cartridge operates to eject ink, three things happen at once: (1) heating by the heating resistor with flow of heat into the ink chamber; (2) cooling by heat drain toward the reservoir, print cartridge body and to ambient; and (3) cooling by carrying away of heat in the ink drops and replacement by cooler ink from the reservoir. The present invention is a method of detecting a depleted ink supply by monitoring the temperature of the printhead substrate with a temperature sensitive resistive trace on the printhead surface. When the print cartridge is warmed with warming pulses to a temperature higher than its normal operating temperature: and then firing pulses are implemented to eject ink, the temperature measured by the thermal sense resistor will decrease if the print cartridge is ejecting its normal, or nearly normal, amount of ink. If the print cartridge is ejecting less than its normal amount of ink the temperature will decrease less, stay the same, or even increase.

Abstract: Higher quality printing is difficult in implementation in spatial light modulator printers. The two major problems are accomplishing gray scale within the line time constraints, and eliminating staircasing artifacts within the images printed (81). It can be improved by using an alternate way of resetting cells on the spatial light modulator when data is being loaded onto the cells, timing delay (86), horizontal offset (84), and differently sized pixels (80, 82).

Abstract: An image forming apparatus includes a photoreceptor allowing an electrostatic latent image to be formed by light exposure, a light source emitting light beams, a light deflecting device for deflecting light beams from the light source, an exposure controlling device for controlling deflecting actions of the deflecting device, and an image-forming optical device receiving light beams deflected by the light deflecting device and image-forming the light beams on the photoreceptor so as to create a latent image composed of a plurality of pixels thereon. In the configuration, the light deflecting device includes a micro-mirror array device which is composed of a multiple number of mirror facet elements arranged matrix-wise, in two-dimensions, and which is disposed so that each row of the mirror facet elements extends in parallel with the rotating axis of the photoreceptor and normals of the mirror facet elements are substantially perpendicular to the rotating axis of the photoreceptor.

Abstract: In a raster output scanning system (ROS) of a xerographic printing device, a plurality of input optical channels direct at least one of a plurality of light beams onto separate facets of a deflector, which may be a rotating polygon mirror. The deflector deflects the light beams onto disparate optical paths. An optical system located on the disparate optical paths directs at least one of the light beams onto each of first, second, third and fourth image receiving locations. The image receiving locations may comprise a plurality of photoreceptors.

Abstract: A laser printer produces a raster image of plural scan lines of image pixels, each raster scan line separated from an adjacent raster scan line by a pitch distance p. The printer includes a movable photoreceptor and n laser sources, where n.ltoreq.2. The laser sources produce n optical beams, separated by a distance of (n+1)p in a direction of movement of the photoreceptor. A scanner scans the n optical beams in parallel paths across the photoreceptor as they are modulated in accordance with pixel data provided from an image buffer. Control circuitry modulates the n optical beams, respectively, with pixel values from one set of n raster scan lines. The n raster scan lines of the set are separated from each other by a distance of (n+1)p. At the completion of each scan, the photoreceptor is moved by a distance (n.times.p). The n optical beams are again modulated with pixel values from another set of n raster scan lines that are respectively, (n+1)p distant from the n raster scan lines of the first set.

Abstract: An imaging system and method employ a linear perceived optical density interface that produces a substantially linear relationship between digital image values generated by an input imaging device and perceived optical densities of corresponding pixels within a visible representation of the image on film. The interface produces a linear change in perceived optical density in response to a linear change in the digital image values, enabling a system user to achieve predictable changes in appearance characteristics by simply adjusting the digital image values. The user can adjust the appearance characteristics in a flexible manner, without being constrained to a set of fixed transfer functions. The user can also perform desired formatting of the image at the input imaging device. The interface provides a single transfer function that is commonly applicable different input imaging devices, such that development of modality-specific transfer functions is unnecessary.

Abstract: A light emitting diode chip includes a substrate carrying thereon a number of light emitting diodes aligned in a row to form an array for producing a number of optical beams parallel to each other in a first direction, and monitoring element provided monolithically on the substrate for detecting the power of the optical beams produced by the light emitting diodes, wherein the monitoring element includes: a reference light emitting diode having a structure identical to the light emitting diodes in the array for producing an optical beam in a second direction perpendicular to the first direction; and a photodiode having a structure identical to the light emitting diodes in the array and separated from the reference light emitting diode by an isolation groove for detecting the optical beam produced by the reference light emitting diode.

Abstract: An ink jet recording head, which can be used in a recording apparatus, is manufactured by preparing a first base plate provided with an energy generating structure for generating energy to discharge ink, preparing a second base plate provided with a discharge opening plate member on which are to be formed ink discharge openings for discharging the ink and recessed portions for forming ink flow paths, the ink flow paths being communicated with the discharge openings, and applying an ink repellant treatment on a surface of the discharge opening plate at a side where the ink is to be discharged in at least an area where the discharge openings are to be formed.

Abstract: Disclosed is a method of determining imminent ink exhaustion in a thermal inkjet print cartridge based on the discovery that ink drop volume falls at a faster rate at high frequency firing rates than at low frequency firing rates as ink supply diminishes. The method includes warming the print cartridge printhead and ink to a predetermined temperature; then operating the print cartridge printhead at a first firing frequency to eject a volume of ink, said operating step including heating the ink and printhead, carrying away heat in the ejected volume of ink, and conveying a volume of cooler ink to the printhead to replace the ejected volume; and monitoring a first temperature change from the predetermined temperature.

Abstract: A laser beam printing device for conducting the print includes a control circuit for controlling a rotation speed of a rotation mirror which reflects the laser beam to scan, an image processing circuit for outputting image information in synchronism with an origin pulse signal, and an origin sensor to receive the laser beam to generate a detection signal and to transmit the signal to the image processing circuit as the origin pulse signal. The control circuit receives the detection signal from the origin sensor as a signal for detecting the rotation speed of the rotation mirror.

Abstract: An image forming apparatus in which two delay time generators input data for two delay times, and a reference signal, and outputs two pulse signals having predetermined pulse-widths. A pulse generator generates a pulse signal based on the phase difference between the two output pulse signals. The pulse-width and pulse position of the generated pulse signal is arbitrarily controlled by the two output pulse signals.

Abstract: A laser scanner control circuit which is used for an apparatus for scanning onto a photo sensitive material by a laser beam and forming and image thereon is constructed as a monolithic driver IC onto a single chip. A reset circuit is provided for a sample-hold circuit so as to minimize the laser power when the image forming apparatus is in a standby mode. A circuit to detect an abnormality of the laser power is further provided. Due to this, the safety of the laser power control of the sample-hold circuit is improved. The operation of the sample-hold circuit can be started at a time point when the laser emitting operation is stable.

Abstract: In an image reading apparatus, an optical unit goes out from a reference stop position, reads an image from a document, and returns to the reference stop position. A position sensor detects a position of the optical unit and output a trigger signal when the optical unit comes to a predetermined position. There is provided a frequency divider to divide a frequency of a pulse signal used to detect the rotations of a driving motor, a pulse width detector to detect the divided pulse width in response to the trigger signal, and a rectifier to rectify an braking amount applied onto the driving motor in accordance with the pulse width so that the optical unit is stopped at the reference stop position.

Abstract: A printer includes an active matrix liquid crystal display (AMLCD) light valve with a matrix of a plurality of filter elements, a backlight that emits a plurality of wavelengths of electromagnetic energy that correspond to the plurality of filter elements, and a multi-layer photoreceptor that is sensitive to the plurality of wavelengths of electromagnetic energy. The backlight flash exposes the AMLCD light valve. The distinct wavelengths of electromagnetic energy passing through each of the filter elements of the AMLCD light valve are focused onto the surface of the photoreceptor. Each layer of the photoreceptor is sensitive to only one of the distinct wavelengths of electromagnetic energy passing through the filter elements of the AMLCD light valve. Thus, a full color latent image is flash exposed onto the photoreceptor. A very compact lenslet array is used to focus the image onto the photoreceptor.

Abstract: In a printer, a controller keeps track of the imager's operation. The original image is transferred into a continuous tone image by using a tone reproduction curve. That signal is encoded into gray pixel data by a halftoner. The pixel data contains the pixel location and the desired darkness of gray, i.e., amount of toner deposited. An imager uses the pixel data to generate the final halftoned image in a printer. A controller generates a feedback signal based on the printer's operation and the quality of the final halftoned image. The imager uses the feedback signal to modify the encoded gray pixel data in order to adjust the final halftoned image. The original coding of the image into gray pixel data is generic and does not depend on the characteristics of the printer being used. This invention reduces the computation of gray pixel data and allows the imager to be separate from the apparatus generating the gray pixel data.

Abstract: A method of using color laser printing technology to create printed matter on heavy sheet stock incapable of being accepted by a color laser printer by instead using a plurality of sheets and laminating them after printing so as to be equivalent in total weight to the weight of the non-acceptable weight sheet stock. Laminating sheet stock enables applications requiring use of heavy weight sheet stock to take advantage of laser printer and computer graphics technology. Graphics are created by use of desk-top publishing software, and then are printed using a high-quality color laser printer onto sheet stock regularly capable of being accepted by color laser printers. Supplies of backing sheet stock are obtained and combined with the laser printed sheet stock so as to obtain an end-product weight comparable to that of a sheet stock weight ordinarily used for the given application.

Abstract: An image recording apparatus in which at least one light beam scans over an inner surface of a cylindrical member to record an image on a recording medium held on the inner surface. A light beam from light beam outputting means advances along a central axis of a cylindrical member and enters an optical head which includes deflecting means and an imaging optical system. The deflecting means and the imaging optical system rotate as one unit. The nodal point of the imaging optical system is located at or close to a point on the central axis which is nearest a beam irradiation position on the recording medium. Hence, displacement of the imaging position is prevented which makes it possible to record a high quality image, even if the optical head wobbles.

Abstract: A method and apparatus for maintaining contact between the recording media and the media support surface of a scanning system. A pressure load is applied on the recording media in the immediate vicinity of a scanning laser beam, thereby ensuring surface to surface contact between the recording media and the media support surface while scanning.

Abstract: A gray scale printer is adapted to modulate an exposure source in both amplitude and duration in accordance with an eight-bit data signal. The printer provides for modulating the amplitude of the exposure source in accordance with the six least significant bits of the data signal, and for modulating the duration of the exposure source in accordance with the two most significant bits of the data signal. Amplitude modulation may effect electrical current to the exposure source, and the duration modulation may effect pulse width of electrical current to the exposure source. The exposure source may be, for example, a laser diode or a light-emitting diode array.