Abstract: A digitizing scanner particularly for scanning transparent films such as X-rays provides an improved illuminator for transmitting light through the film. The illuminator defines a line array of a plurality of individually calibrated and controlled LEDs. The LEDs are calibrated by determining their relative points of projection on a CCD camera array. The camera array scans the LEDs and adjusts them individually to produce a predetermined illumination pattern from the group. The adjustment occurs over a plurality of cycles that address cross-talk between LEDs in the array. The camera includes anti-reflection elements to minimize bounce-back of image light and noise suppression circuitry to reduce low-level signal noise. A central processing unit, interconnected with the camera assembly includes a pixel averager to reduce the inherent resolution of the CCD to a desired level and to attenuate further noise.

Abstract: A sheet feeding mechanism for a digitizing scanner particularly adapted to feed transparent and translucent film sheets provides two pairs of feed rollers each located on an opposing side of the scanner camera's image line. A tray for supporting a feed stack is provided. The tray pivots into and out of engagement with a pick roll at predetermined times during the feed cycle. The pick roll rotates to feed the top sheet of the stack into the feed rollers. The top sheet must climb a curved stripper that resists downstream movement of the next sheets in the stack. A pair of edge sensors are located upstream of the upstream feed rollers and downstream of the downstream feed rollers. The sensors sense, respectively, the trail edge and the lead edge of the sheet, respectively and enable a central processing unit to automatically determine the length of the sheet. The sheet can, thereby, be reversed and scanned fully over its entire length.

Abstract: A dual drum rotary image scanner has a headstock and a tailstock between which may be mounted drums of different diameter. The tailstock has substantially annular surfaces which contact corresponding surfaces on the different diameter drums. The different drums, when held in the scanner, each create a different separation between the headstock and tailstock. These different separations are detected by photodetectors, the outputs of which are received by a system controller. The controller uses the photodetector signals to control motors that position the scanning head and the transmittance illuminator relative to the surface of the particular drum mounted in the scanner. The motors turn pinions which, in turn, move racks to which are attached the scanning head and the transmittance illuminator, respectively. The movement of the scanning head also results in the modification of the optical path within the optics box of the scanner.

Abstract: A high quality, relatively inexpensive rotary scanner provides both transmission and reflection scanning of documents mounted on a rotary drum. The drum translates with respect to an imaging lens located adjacent the drum and on the exterior thereof. A first illuminating element surrounding the imaging lens illuminates the document on the drum for reflection scanning; a second illuminating element mounted on a cantilevered arm extending along the axis of the drum illuminates the document for transmission scanning. Focusing of the image is performed either automatically or under the control of the user. A high resolution and wide dynamic range is provided by a set of photomultiplier tubes which receive light from the imaging lens by way of an aperture wheel which provides apertures of selectable size in accordance with the desired resolution. User replaceable lamp modules allow the precise positioning of high intensity replacement lamps without need for a technician.

Abstract: A rotary color scanner has both linear and logarithmic mode static and dynamic calibration to quickly and automatically calibrate the scanner before each scan, as well as during a given scan, without operator intervention of any kind, whether in the factory or in the field. Close calibration is achieved, despite the use of photomultiplier detectors which are inherently particularly susceptible to drift, and despite the use of high intensity lamps whose output typically varies greatly with aging. The system establishes operation at an optimized data throughput rate up to a limit determined by the maximum scan rate of the system, and thereafter switches to operation at an optimized signal/noise ratio.

Abstract: A drum for a rotary scanner operable in both a transmissive and a reflective mode is manufactured to high concentricity yet relatively inexpensively by mounting an oversized (in thickness) drum blank of possibly varying diameter and thickness on a cylindrical mandrel and thereafter turning it on a lathe to the required external radius. End caps containing mounting means defining the effective scan axis are then secured to the drum for subsequent mounting in a rotary scanner.

Abstract: A rotary color scanner has both linear and logarithmic mode static and dynamic calibration to quickly and automatically calibrate the scanner before each scan, as well as during a given scan, without operator intervention of any kind, whether in the factory or in the field. Close calibration is achieved, despite the use of photomultiplier detectors which are inherently particularly susceptible to drift, and despite the use of high intensity lamps whose output typically varies greatly with aging. The system establishes operation at an optimized data throughput rate up to a limit determined by the maximum scan rate of the system, and thereafter switches to operation at an optimized signal/noise ratio.

Abstract: Color printing characterized by high color density and color contrast is provided by jetting an ink composition composed of an optically clear, phase change base material and a primary subtractive color dye which is soluble in the base material onto the surface of a printing medium to form a multiplicity of closely spaced color dots or spots arranged to define a line or character on the medium. Each dot consists of one or more well defined, optically clear, semitransparent color layers each of which has a different color so that the observed color of each dot is a true subtractive mixture of the colors in the layers. Specific ink compositions are also disclosed.

Abstract: A head tending apparatus for an ink jet printing system with at least one ink jet being disclosed. The apparatus includes a solvent supply system for spraying solvent on the faces of the ink jets and in the jet openings and a brush for scrubbing the ink jet faces during and immediately after the spraying process. Solvent vapors enter the jets and deprime the jets so that the ink remaining in the jets drains out of the jets back to the ink reservoir allowing solvent vapors to penetrate the jets to the reservoir. Resultantly, when the jets are next primed with ink, the jets are substantially free of air bubbles. Head tending is normally performed when the printer is shut down, or prior to the priming of the ink jets.

Abstract: A color reproduction controller accesses corrected color values for driving an output color reproduction device by forming, for each color value of each pixel to be reproduced, a data pointer comprising a first word portion of a first color value and second and third word portions of second and third color values, the second and third word portions being smaller than the first word portion. The resultant words are smaller than those of the combined length of the color values from which they are formed and result in significantly smaller memory space.

Abstract: A head tending apparatus for an ink jet printing system with at least one ink jet is disclosed. The apparatus includes a solvent supply system for spraying solvent on the faces of the ink jets and in the jet openings. The apparatus also has a brush for scrubbing the ink jet faces during and immediately after the spraying process. The solvent loosens and dissolves any solid matter that may have formed on the jet faces or in the jet openings and also deprimes any ink remaining in the jets when the printer is shut down; the brush cleans the loosened matter off the jet faces. If the printer has a rotating image insert assembly with the ink jets thereon, the brush and a solvent jet are mounted to a shell adjacent the ink jets. The brush includes a bristle-free section that is normally adjacent the image insert assembly and spaced away therefrom when the head tending appartaus is deactivated; this prevents the apparatus from interfering with the normal operation of the printer.

Abstract: An ink for hot-melt ink-jet printing comprising a benzoate solvent which is solid at room temperature. This ink is suitable for jetting onto an opaque substrate such as paper for directly readable print, or onto a transparent substrate, such as an acetate or polycarbonate sheet, to make a projectable transparency.

Abstract: An ink curing apparatus for use with an ink jet printer that discharges liquefied ink is disclosed. The apparatus includes a shell assembly disposed around the portion of the printer imaging assembly that includes the ink jets. The imaging assembly and the shell wall are shaped so that a first cavity is formed between the imaging assembly and the paper printed on, and a second cavity is formed between the paper and the shell wall. A pair of fans are arranged to draw air currents over both sides of the portion of the paper that is being printed on. The air currents cool the paper so the ink solidifies upon contact with the paper and does not soak through it. The air currents also insure that the ink solidifies at a uniform rate regardless where it is applied on the paper. This insures the final image on the paper has a uniform appearance.

Abstract: An ink jet priming system for an ink jet printer having a reservoir containing ink for ink jets connected thereto and a reservoir opening for receiving ink is described. The ink jet priming system is provided with a seal for selectively closing the reservoir opening. Pressurized air is supplied to the reservoir from a tank connected thereto through an opening in the seal. The flow of air to the reservoir is controlled so that there is an initial low pressure air flow to force ink into the jets followed by a high pressure flow to force the discharge of the streaming discharge of the ink. A gutter assembly, connected to a disposable waste container is provided for receiving and collecting the ink discharged during the priming process. The ink jet priming system can be used with a moving print head that contains two or more separate reservoirs each with a separate reservoir opening.

Abstract: A solid ink delivery system for supplying sticks of solid ink to a ink jet printer is disclosed. The solid ink delivery system includes a delivery assembly for each color ink stick supplied to the printer. Each delivery assembly includes a tube assembly where the ink sticks are stacked prior to their delivery to the printer. A triggerable ink stick feed assembly is provided for normally holding the in sticks in place. When triggered, the ink stick feed assembly releases the bottommost ink stick or sticks to an opening in the printer adapted to receive them, and restricts the movement of the above stacked ink sticks. The solid ink delivery system is adapted for use with a moving print head having a number of reservoir openings each adapted to receive ink sticks of a different color. A positioning means aligns the print head so the reservoir openings are under the tube assemblies that supply them with the appropriate color ink.

Abstract: A hot-melt ink for an ink jet printer is formed from a solid organic solvent having a melting point less than 150.degree. C. and a low molecular weight thermosetting resin having a high hydroxyl number, together with a dye. The ink has excellent jetting characteristics, forms a hard, stable print raised above the surface of the substrate, provides high dot resolution, and remains colorfast both in the ink jet printer and on the paper, even when exposed to continued high temperatures. It is non-toxic and odorless, and eminently suitable for office document preparation and other applications. In a preferred embodiment, the inks comprise color subtractive dyes, making them suitable for use in multi-color printing.

Abstract: Color printing characterized by high color density and color contrast is provided by jetting an ink composition composed of an optically clear, phase change base material and a primary subtractive color dye which is soluble in the base material onto the surface of a printing medium to form a multiplicity of closely spaced color dots or spots arranged to define a line or character on the medium. Each dot consists of one or more well defined, optically clear, semitransparent color layers each of which has a different color so that the observed color of each dot is a true subtractive mixture of the colors in the layers. Specific ink compositions are also disclosed.

Abstract: A printed record in color comprises a transparent sheet on which is jet-printed subtractive color inks in layers of different color. The inked surface of the transparent sheet is adhered to the surface of an opaque backing sheet, usually white in color, so that the backing sheet reflects ambient light back through the ink layers and the transparent sheet so as to provide a color image visable through the transparent sheet that is characterized by high color density and brightness.

Abstract: A rotary ink jet printer can print at high speed in black and white as well as in color using hot-melt inks. The printer includes a rotary print wheel which supports a plurality of ink jetters distributed around its periphery. The jetters are divided into color groups with the jetters in each group drawing ink from a separate chamber of an ink reservoir with the different chambers containing different-colored inks. Each jetter can be aimed separately from all of the other jetters in the print wheel in a direction parallel to the rotary axis of the wheel as well as in a direction perpendicular thereto and tangent to the print wheel, enabling the jetters in the different groups during each revolution of the print wheel to print in a plurality of colors on a plurality of different lines of a recording medium advancing as a cylinder past the periphery of the print head. A mechanism for automatically aiming the jetters on the print wheel is also disclosed.

Abstract: A printed record in color comprises a transparent sheet on which is jet-printed subtractive color inks in layers of different color. The inked surface of the transparent sheet is adhered to the surface of an opaque backing sheet, usually white in color, so that the backing sheet reflects ambient light back through the ink layers and the transparent sheet so as to provide a color image visable through the transparent sheet that is characterized by high color density and brightness.