Hewlett-packard Company

Texas Instruments Corporation

Other

Hewlett-packard Development Company, L.P.

James G Bearss

Thomas Camis

Dale D Russell

C S Chan

Jeffrey Scott Weaver

Terry M Nelson

George Henry Kerby

Eugene A Roylance

Arlin R Jones

Kent D Vincent

Bruce Cowger

David J Arcaro

John W Huffman

David E Hackleman

James A Hall, Jr

Gary E Hanson

Phillip R Luque

Michael Joseph Martin

Eric Robert Hansen

Chris A Storlie

Eldurkar V Bhaskar

Kenneth A Norton

Nancy Cernusak

Judd E Heape

Gar P Kelly

Pochiraju Srinivas Rao

Herman W Harrison

Wesley L Meyer

Wayne E Bradburn

A method of data processing is described for generating a screened bitmap in an adaptive manner. The page being printed is subdivided into a plurality of smaller areas, and the optimal screening method is selected based on the content of the data being processed. Areas of the page that primarily comprise of graphic elements and/or fonts are screened as part of the rendering process, while areas that are primarily continuous tone elements are screened as a secondary step after the rendering process.

Adaptive screening in raster image processing of complex pages

This invention comprises a converged printer architecture for controlling both electro-photographic (EP) processing and raster image processing (RIP) of data for laser modulation over a video line. By converging EP process control with image processing control, significant advantages in cost, image quality, and output stability are achieved. A digital signal processor (DSP) serves as the central processing resource of the architecture. The DSP is well suited for the dual role of image processing and real-time feedback process control. The DSP can operate in open loop motor/motion control, print process control, and in closed loop feedback control including image processing adaptations for quality and stability enhancements.

Integrated raster image processor and electro-photographic engine controller

The processor enhanced memory module PEMM can be incorporated into the hardcopy image processing pipeline of existing printer controllers by using the smart memory model. Here the data generated from RISC based PDL interpretation or pre-rasterized data can be processed in an accelerated fashion into page bit maps, color space converted, and compressed by the PEMM. Since the DSP on the PEMM is programmable, the resolution, color space, and type of compression along with other printer specific processing can have formats other than those determined by the fixed functionality of the ASIC devices present in the pipeline.

Using a processor enhanced memory module to accelerate hardcopy image processing within existing printer controller

Lower resolution source data is synthesized to a higher resolution format for subsequent rendering on a lower resolution output device. Synthesis occurs by selecting or generating and using a synthesis template that represents a configuration of a plurality of pixel data in the higher resolution format into which the lower resolution source data is to be synthesized. A working or active pixel is identified from the lower resolution source data, a synthesis template is selected, and then the synthesis template pixel data is substituted for the working pixel for rendering on the output device. The synthesized higher resolution data is rendered in a manner such that dots represented by the synthesized data are formed interstitially relative to scan lines of the given lower raster/resolution capability of the output device. The working pixel is identified in the lower resolution data by recognizing a configuration of a plurality of pixel data adjacent the working pixel. The synthesis template comprises at least a two by two cell matrix for pixel placement in the higher resolution format. The synthesis template pixel placement is formed to provide an apparent merge of the pixel data in the higher resolution format with the adjacent pixel data of the lower resolution format data.

Programmable mapping of lower resolution digital data to a higher resolution for output on a lower resolution device

Methods of providing lower resolution format data into higher resolution format are described. A laser printing system is provided having first and second lasers configured to receive and be driven by raster data. Image data, which is to be rendered onto a print medium is received in a first resolution format. The first resolution format is converted into a second resolution format which is greater than the first resolution format by mapping the image data to provide mapped image raster data in the second resolution format. The first laser is driven with a portion of the mapped image raster data, and the second laser is driven with another portion of the mapped image raster data.

Methods of providing lower resolution format data into a higher resolution format

The present invention includes image forming devices, imaging assemblies, sensors, and methods of forming an image. One aspect of the present invention provides an image forming device including a housing configured to guide media along a media path: an input device configured to receive an image; a sensor adjacent the media path and configured to monitor the media and to generate a signal responsive to the monitoring; and an imager adjacent the media path and configured to provide developing material corresponding to the image upon the media according to an imaging parameter and to adjust the imaging parameter responsive to the signal.

Image forming devices, imaging assemblies of image forming devices, and methods of forming an image upon media

Methods of providing lower resolution format data into higher resolution format are described. In one embodiment a first predetermined amount of image data is provided which is to be rendered onto a print medium. The first predetermined amount of image data is provided in a first resolution format. Using the first predetermined amount of image data, the first predetermined amount of image data is replicated into multiple predetermined amounts of data sufficient to provide said first predetermined amount of image data into a second resolution format which is greater than the first resolution format. At least one laser beam in a laser printer system is modulated using the multiple predetermined amounts of data.

Methods of providing lower resolution format data into higher resolution format

The present invention relates to image forming devices, fusing assemblies and methods of forming an image. According to one aspect of the invention, an image forming device includes a housing including a media path configured to guide media in a downstream direction within the housing; an input device configured to receive an image; a developing assembly adjacent the media path and configured to provide developing material; a sensor adjacent the media path and configured to determine a qualitative characteristic of the media and to generate a signal indicative of the qualitative characteristic; and a fuser adjacent the media path and configured to adjust a fusing parameter responsive to the signal and to fuse the developing material corresponding to the image to the media and according to the fusing parameter.

Image forming devices, fusing assemblies, and methods of forming an

The present invention includes image forming devices, imaging assemblies, sensors, and methods of forming an image. One aspect of the present invention provides an image forming device including a housing configured to guide media along a media path; an input device configured to receive an image; a sensor adjacent the media path and configured to monitor the media and to generate a signal responsive to the monitoring; and an imager adjacent the media path and configured to provide developing material corresponding to the image upon the media according to an imaging parameter and to adjust the imaging parameter responsive to the signal.

Image forming devices and sensors configured to monitor media, and

Text and line art image data is distinguished from halftone image data for selectively enhanced rendering thereof. Specifically, a method of rendering a raster pixel image from a stored bitmap includes (i) determining whether an orphan pixel is detected within a bounded sampling window of the bitmap, and, (ii) processing at least one selected pixel of the bitmap within the sampling window relative to the determining of whether an orphan pixel is detected. In general, an orphan pixel is defined as an isolated white or black pixel in a halftone image. In one embodiment, an orphan pixel is recognized as having a predefined pixel value and as having no other pixels with that value adjacent thereto within the sampling window. In the event an orphan pixel is detected within the window, then the bitmap within the window is determined to be halftone image data and the selected pixel is processed accordingly. In the event an orphan pixel does not exist within the window, then the bitmap within the window is recognized as text or line art image data and processed respectively. In addition, a method of forming a dither matrix for a halftone image includes generating a pixel pattern such that an orphan pixel exists within the pattern of the dither matrix. The orphan pixel is designed into the halftone image. This measure increases the probability that orphan pixels will exist and be detected in the resultant raster image array. Thus, during subsequent rendering of the raster pixel image, selective application of resolution enhancement techniques may occur based on whether or not an orphan pixel is detected in the sampling window.

Encoded orphan pixels for discriminating halftone data from text and

A printing system for printing multiple colors on a sheet of print media includes an electrophotographic printer having a photoconductor drum and a transfer roller configured to interact in co-rotation with the drum during transfer of a color image plane from the drum onto a sheet of print media passed therebetween. A paper drive sheet feeder system is included which has a grit shaft extending generally transverse of a paper travel path, a first pinch roller configured to interact in co-rotation with the grit shaft along a first edge of a sheet of print media, and a second pinch roller configured to interact in co-rotation with the grit shaft along a second edge of the sheet of print media. The grit shaft is driven in rotation to drive the sheet of print media along a bidirectional sheet travel path such that a plurality of different colored image planes is superposed onto the sheet of print media in accurate registration therebetween. A method for printing multiple colors is also described.

Color printer with shuttle type paper drive and method

A toner projection printer is provided with a developer surface which manifests a developer bias, and includes a cloud of entrained toner particles. A platen structure is positioned opposed to the developer surface and manifests a platen voltage that is attractive to the toner particles. An address plate is positioned between the developer surface and the platen structure. The address plate includes a determined thickness insulator with through pixel apertures. Each pixel aperture has at least first and second conductors that are electrically insulated from each other by the insulator, and a screen electrode for distorting the electric field between the address plate and the platen structure in a manner to reduce toner spreading. A first drive circuit is coupled to the first conductor for controllably applying a row drive voltage which is either a reference potential that exerts a repulsive force on the toner particles or a high voltage which is attractive to the toner particles. A second drive circuit is coupled to the second conductor for controllably applying a column voltage drive that is either a reference voltage (repulsive to the toner particles) or a high voltage (attractive to the toner particles). Both the column and row drive voltages are set at levels so that only when both are high can toner particles pass through the pixel aperture, be drawn towards the conductive platen and come under influence of the platen voltage. Control circuitry operates the first and second driver circuits to enable deposition of row and column dots of toner on a media sheet positioned on the platen, under influence of the platen potential. An improved platen structure is also shown which further reduces toner spreading.

Toner projection printer with means to reduce toner spreading

A color printer incorporating the invention hereof includes an ionographic image projection head which employs AC and DC potentials to provide an ion pool from which ions may be projected onto a movable dielectric surface. Plural developer modules are arranged about the dielectric surface, each developer module including an ion imaging head and a color toner module. Each developer module, after ion-beam imaging the movable dielectric surface, develops the charge image on the dielectric surface by bringing it into contact with a single color toner module. A processor controls each ionographic image projection head and each associated toner module to immediately apply the color toner after imaging of the dielectric surface. A transfer station is located downstream from the plural developer modules and enables transfer of the full color toned image from the dielectric surface to a sheet after a single pass of the dielectric surface past the plural developer modules.

Ionographic color printer with plural print heads removable toner

Various laser patterns for vertical cavity surface emitting lasers are disclosed. The patterns utilize lasers with different size apertures. By utilizing these laser patterns, an image forming system is able to form images with improved resolution and halftoning. Apparatus and method implementations which use these laser patterns are disclosed.

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Boise, ID, United States of America

James G Bearss