Abstract: A wiper assembly is used to mount large size wiper blades for use in industrial inkjet printers. In order to provide an even wiping action over the length of a print head the wiper is sideways clamped in a rigid wiper blade holder and held in place by a clamping block. Preferably the wiper assembly clamps the wiper over about 20% of the wiper height. The assembly allows for use of individual wiper blades having different characteristics. Separate wiper blades are more easily fabricated and can be replaced easily. The wiper blades may be provided with a heel which enhances mounting efficiency. The wiper assembly may include provisions for easy mounting to allow for rapid exchange of the whole wiper assembly in a printer.

Abstract: The present invention relates to ink jet printing, and more particularly to a method of printing and an apparatus for providing images having grey levels of varying intensity. The present invention provides a method and device for printing grey scale images on a printing medium. The method includes delivering at least a number of first droplets of printing material of a color with a first volume from a first printhead and a number of second droplets of printing material of that color with a second volume from a second printhead, the first volume and the second volume being different, and merging together the number of first droplets and the number of second droplets on a target pixel position on the printing medium to obtain a given greyscale dot on the printing medium.

Abstract: A multilevel printing process can be calibrated by: measuring a small number of recorded patches obtaining data points characterising the printing process, modeling a gradation of the printing process with a model curve incorporating different gradation behaviour of the printing process in different regimes based upon the obtained data points, and using the model curve to obtain a gradation-correction curve for calibrating the printing process, where it is sufficient to use only patches obtained by filling every pixel in a patch with a same recording level.

Abstract: A method to convert a color provided in a first color space into a color in a second color space defined by more than four colorants and a reproduction process. The method includes converting the color into a third color space, determining which of a set of gamut volumes defined in the third color space is appropriate for the color, with each point in the gamut volume achievable by an area coverage greater than zero and less than 100% of two of the colorants and an area coverage greater than zero and less than 100% of one or more darkening colorants with the remaining colorants either absent or at 100%. The method further includes carrying out any gamut mapping on the converted color so that the converted color is in the appropriate gamut volume and converting the gamut mapped color from the third color space into a set of the colorants of the second color space, such that the surface of any gamut volume with no darkening colorant is part of an umbrella surface for the N inks.

Abstract: Several methods for retrospective correction of intensity inhomogeneites in digital diagnostic radiation images are presented. The methods are based on the correction of a digital image representation by means of a bias field. The bias field is deduced from the digital image representation of the diagnostic radiation image.

Abstract: The invention relates to an image carrier for the storage of X-ray information, and includes an electronic memory in which data can be stored. In order to reduce the danger of loss of data it is envisaged that the image carrier comprises a mark that represents at least a part of the data stored in the electronic memory.

Abstract: A printing method and apparatus is disclosed for printing an image on a printing medium by means of a printing head having a first number n of marking elements, the method includes printing the image as a set of N sub-images, N being a number C of colours used for printing multiplied by a number I of interlacing steps and multiplied by a number P of mutually interstitial printing steps (N=C*I*P), where the number I of interlacing steps is greater than 1. Each interlacing step generates an interlaced sub-image, a swath of an interlaced sub-image being printed during a printing pass. There is at least one linear relative movement between the printing medium and the printing head over a uniform transport distance TD in a slow scan direction between the printing of two subsequently printed interlaced sub-images.

Abstract: An imaging system includes a first off-axis illumination source for providing a first illumination field at a surface of an illumination modulator such that when the modulator is in a first non-activated mode a zero-order reflected illumination field is directed toward a first illumination blocking device, and when the modulator is in a second activated mode one first order reflected illumination field is directed toward an imaging surface while another first order reflected illumination field is directed toward a second illumination blocking device.

Abstract: A plate cassette loader for a platesetter comprises a cassette holder for receiving a cassette, containing a stack of plates. A cassette inverter then rotates this cassette to a feed position in which the plates can be fed into the imaging engine of the platesetter. In this way, the somewhat unwieldy process of loading plates into the imaging engine is handled by the cassette inverter, in combination with the fact that the stack of plates, contained in the cassette, can be loaded in one step, rather than requiring the feeding of individual plates by a dedicated operator.

Abstract: A device and method prevents movement of a printing plate during clamping of an end of the plate to an external drum of an imaging system using a clamping apparatus having: a clamping portion disposed on the external drum, wherein the clamping portion may be selectively displaced between a clamping position for clamping the leading edge of the printing plate against the external drum and a release position; and an inflatable member positioned between the clamping portion and the external drum for displacing the clamping portion between the clamping position and the release position. The device includes: a first spring-metal component mounted onto the external drum wherein the end of the plate can be positioned between one end of the first spring-metal component and the external drum, and the first spring-metal component is positioned between the clamping portion and the plate, to prevent the plate from moving during clamping.

Abstract: A method, apparatus, and product to generate trap areas. One embodiment is a method for generating a trap pixel of a trap area surrounding one or more trapping edges of an image that includes, for each trapping edge in the image, and for each pixel within a predefined area around the trapping edge, comparing the distance of the pixel from the trapping edge according to a distance measure with a provided measure indicative of the distance of the pixel from any edge of the image to determine if said each pixel is closer to the trapping edge than to another edge. The method further includes, if said pixel is closer to said edge than to any edge, setting the pixel as a trap pixel of the trap area, including setting a trap color for the trap pixel.

Abstract: A substrate manager for a substrate exposure machine is used, in one example, as a platesetter. As such, it comprises a substrate storage system, containing one or more stacks of substrates, such as plates in one implementation. A substrate picker is provided for picking substrates from the stack of substrates. The substrates are then handed to a transfer system that conveys the substrates to an imaging engine. According to the invention, a substrate inverter system is also provided. This system inverts the substrates from being imaging or emulsion side down to emulsion side up in the present implementation. This allows plates, for example, which are stored emulsion side down in cassettes to be flipped to an emulsion side up orientation, and then transferred, using the substrate transfer system to the imaging engine. This flipping process has two advantages. First, the plates can be emulsion side up during the transfer. This prevents any damage to the sensitive plate emulsions.

Abstract: An apparatus and a method for making a digital color proof of an image on a surface of a receiving substrate, the apparatus including a plurality of application stations for imagewise applying each a specific type of marking particles to the surface of the receiving substrate, the application stations including a first number N1 of first application stations for applying marking particles of a first, dominant color and a second number N2 of one or more second application stations for applying marking particles of a second, non-dominant color, wherein N1 is larger than N2.

Abstract: An imaging system is disclosed including a first illumination source for producing a first illumination field, a modulation system for modulating the first illumination field, and an optical imaging system for directing the modulated illumination field to an imaging surface along a first optical path. In accordance with an embodiment, the imaging system includes a second illumination source for producing a second illumination field, a first sub-assembly, a second sub-assembly and a control assembly. The first sub-assembly is for directing the second illumination field toward the imaging surface along a second optical path that is different than and non-parallel with said first optical path. The first sub-assembly includes a beam splitter sub-assembly that includes a beam splitter and at least one lens. The second sub-assembly is for receiving a portion of the second illumination field from the imaging surface, and includes a lens and a sensor for producing a sensor output signal.

Abstract: A substrate manager for a substrate exposure machine is used, in one example, as a platesetter. As such, it comprises a substrate storage system, containing one or more stacks of substrates, such as plates in one implementation. A substrate picker is provided for picking substrates from the stack of substrates. The substrates are then handed to a transfer system that conveys the substrates to an imaging engine. According to the invention, a substrate inverter system is also provided. This system inverts the substrates from being imaging or emulsion side down to emulsion side up in the present implementation. This allows plates, for example, which are stored emulsion side down in cassettes to be flipped to an emulsion side up orientation, and then transferred, using the substrate transfer system to the imaging engine. This flipping process has two advantages. First, the plates can be emulsion side up during the transfer. This prevents any damage to the sensitive plate emulsions.

Abstract: A method for characterizing exposure levels in a platesetter comprises exposing regions of a plate at different exposure levels by modulating the power of an exposure beam and then analyzing the plate after development to determine a desired exposure level for plates on the platesetter by reference to the regions receiving the different exposure levels. The plates are preferably exposed in an area outside of a printing area. In this way, the exposure test can be performed as part of the normal plate printing process. The plate is not consumed. Moreover, the plate exposure setting can be constantly monitored throughout production in one implementation.

Abstract: A nip mechanism for a substrate transfer system includes: a first nip roller; a second nip roller located substantially vertically above the first nip roller; and a drive motor for driving the first nip roller and the second nip roller to feed a substrate between the first nip roller and the second nip roller when the drive motor is driven in a first direction. The second nip roller creates and maintains a nip with the first nip roller due to a force of gravity without using a spring or other mechanical device while the drive motor is driven in the first direction. The drive motor engages a one-way clutch for engaging a roller separation mechanism to raise and separate the second nip roller from the first nip roller when the drive motor is driven in a second direction. The first and second nip rollers maintain substantial vertical alignment with one another when the drive motor is driven in either direction.

Abstract: A method and apparatus is disclosed to precisely locate an edge of an imageable plate mounted on a drum or other support surface. A light source and light sensor are used to measure the difference in reflectivity between the plate and the support surface. The drum or support surface contains at least one groove to increase the difference in reflectivity between the plate and the support surface. The groove may also contain an anti-reflecting layer to further increase the difference in reflectivity. The groove may also have a geometric shape that causes incident light to be directed away from the light sensor.

Abstract: The present invention provides a method and apparatus for cleaning a coating material from a surface of a print substrate mounted on the plate cylinder of a printing press using an ultrasonic acoustic cleaning apparatus. The method comprises: applying a cleaning solution onto a surface of the print substrate, rotating the plate cylinder to displace the print substrate under an ultrasonic acoustic cleaning apparatus to dislodge a coating material from the surface of the print substrate, and removing the dislodged coating material and the cleaning solution from the print substrate using a vacuum system.