Abstract: A method and apparatus to accurately control the size of the spots or dots produced by individual lasers within an array of lasers of an image scanning device is disclosed. The lasers are driven in accordance with image information indicating an image to be scanned onto the image bearing member. Output intensity feedback information from each of the lasers is obtained by monitoring an intensity output from each of the lasers. Using this feedback information, the driving energy values of the lasers are adjusted to overcome any unwanted nonuniformities or otherwise calibrated. The invention can also be implemented as an apparatus. Regardless of how the invention is implemented, an image scanning/forming apparatus utilizing the invention is able to scan or print with an array of lasers without being susceptible to streaks and other defects which otherwise occur during the printing or scanning of an image when all of the lasers do not function in a uniform and consistent manner.

Abstract: An electroluminescent device used as an illuminating source in a scanner. The device includes at least one solid-state electroluminescent element, which has a transparent electrode with a top surface, a radiation generating stack under the transparent electrode, and a second electrode with a bottom surface under the radiation generating stack. Radiation is generated from the radiation generating stack when a selected voltage source is coupled across the electrodes. Most of the radiation generated is emitted either from the top surface or from (the top and the bottom surfaces). When the scanner scans a medium, the emitted radiation is substantially uniform at least across the top surface of the transparent electrode to create a uniform radiation source for illuminating the medium.

Abstract: A broadband line source that is directional, rugged, compact, spatially and temporally uniform, stable, without the need for warmup, and relatively easy to implement. The source can be in single-color or multi-color, and it can be used, for example, in a scanner. In one embodiment, the line source includes a first thin-film electroluminescent stack with at least a bottom electrode, a top electrode, and a first active film between the two electrodes. The active film generates radiation in an area that has a width and a length, with the length being larger than the width. The length of the area sets the length of the line radiation, which is substantially homogenous along the line. In another embodiment, three of such stacks are encapsulated through thin-film processes by a cap, which sits on a substrate. The cap has one side surface that is more transmissive to radiation.

Abstract: A desktop printer for plain paper sheets includes the integral combination of a color printer and a text printer. The color printer is of the inkjet type to print color images incrementally and the text printer is of the laser-electrophotographic type to print monochrome text continuously. The printing information is segregated into color and text components, and the color printer is controlled to print only color components while the text printer is controlled to print only text components. A conveyor transports sheets from the text print engine to the color image print engine with incremental indexing motion.

Abstract: A high pressure meter pump system with improved accuracy is provided by subdividing a large meter pump capacity into metered subvolume charges which are incrementally delivered to a high pressure slave pump.This enables the pump sytem to achieve improved accuracy independent of flow rate and therefore increasing the range of flow rates available with acceptable accuracy. Additionally, the pump system self-primes independently of flow rate and therefore does not require degassing of the solvent being pumped.

Abstract: A new mechanism for pulsation damping in a reciprocating diaphragm pump system is disclosed which is especially suitable for solvent delivery in modern high pressure liquid chromatography requiring a wide range of solvent flow rates and pressures. The disclosed damper has good overall performance over the full range of liquid chromatographic conditions, a dead volume independent of solvent pressure, and largely eliminates the necessity for continuously pumping the working oil of the diaphragm pump to a maximum operating pressure.

Abstract: In U.S. Pat. No. 3,906,199, issued to R. B. Kieburtz and K. V. Mina on Sept. 16, 1975, limit cycle noise is reduced in a second order recursive digital filter by a circuit which randomly inhibits the rounding signal in one of the digital multipliers disposed in the filter. It has been found, however, that in certain instances, this approach results in even longer transients.In accordance with the present invention, random inhibiting is constrained to instances in which limit cycle noise is reduced, by monitoring, with suitable logic circuitry, the signals present in the various feedback loops of the filter. Generally, it has been found that the inhibiting circuit should be allowed to operate only if D.sub.1 and D.sub.2 satisfy predetermined magnitude and polarity relationships, where D.sub.1 .ident. a version of the filter output signal Y(n) that is removed in time by one sample interval, and D.sub.2 .ident. a version of the filter output signal Y(n) that is removed in time by two sample intervals.