Abstract: Fixed pattern odd/even noise in the video signal output from a self-scanned photosensor array is substantially eliminated by integrating the video signal at the cell scan rate, and converting the resultant to a pulse having a width proportional to the charge current generated by a photosensor cell. Even and odd pulses corresponding to alternate sensor cell video signals are produced, and the pulse widths are compared to form a correction signal. A current sink responsive to the correction signal adjusts the output of the integrator during even cell scans to eliminate fixed pattern odd/even noise in the output video signal.In a specific embodiment, the fixed pattern odd/even noise correction system coacts with an AGC control system and a black reference control system to substantially eliminate fixed pattern odd/even noise and cell clock noise in the output video signal, and to provide an effective system immunity to variations in the parasitic capacitance of the photosensor array.

Abstract: A modulator for ink jet printers is provided for operation over a wide bandwidth of high frequency drop rates. The longitudinal dimensions of each part of the modulator are made small compared to the wavelength of the shortest standing longitudinal acoustic wave that may be produced in a structure of the same material as the part in question. A piezoelectric crystal is seated within a mount acoustically decoupled at the edges therof. An electrode is axially aligned with the crystal and placed in contact with the crystal. A short hollow cylinder forms an ink chamber axially aligned with the crystal. The end of the ink chamber opposite the crystal is closed by a front plate having a nozzle axially located therein.Plural nozzles may be utilized to produce parallel ink streams which break into droplets at substantially the same time and at a near uniform distance from the nozzles.

Abstract: Signature verification where an image mosaic for a signature to be verified is stored in a memory and wherein a prototype feature set for said signature is stored in memory. Binary signals representative of the location and magnitude of positive and negative peaks in mosaic and the stroke character in the region of each of said peaks are generated. A two-dimensional feature set patterned after the prototype set is stored with the signals ordered in dependence upon the occurrence of the peaks in the signature and accompanied by (i) peak rank in terms of peak magnitude and (ii) stroke character in the vicinity of each peak. The feature vector set is then compared with the prototype vector set and identity is signaled when within predetermined limits the feature set matches the prototype set.

Abstract: Automated processing of bank checks encoded with alphanumeric characters on the face of each check by transporting said checks as a serial constant velocity train through a processor to a sorter while at a first station generating an item control number unique to each document and at a second station sensing each character in the encoded line to produce a string of data signals for each document. At a third station the control number and other data is imprinted on the back of each document in code form and the control number and other data is imprinted on the face of each document in human readable form.

Abstract: In biphase operations where logic 1's are represented by a logic 0-1 code in a data stream which controls bar code printing, and logic 0's are represented by a logic 1-0 code, the invention involves altering to a logic 0-0 code in the stream each logic 1-0 code which follows a logic 0-1 code.In a more specific aspect, binary information signals are encoded for detection by a reading system effective within a bandwidth of bar densities. Such encoding is effected by sensing each bit time period of the binary information signal, and representing a logic one level occurring within a bit time period by inserting a logic one level in a trailing half of a corresponding bit time period of an encoded signal. If a logic zero level is sensed in a bit time period of the binary information signal after the detection of a logic one level in an immediately preceding bit time period, logic 0's are inserted in the leading and trailing halves of a corresponding bit time period of the encoded signal.

Abstract: A method and system is provided for driving a self-scanned photosensor array at high sensor cell scan rates, and sampling the sensor cells serially addressed by the array without comprising either image integrity or array frame rate.End of line (EOL) and end of frame (EOF) timing signals generated by the array are sensed and operated upon to limit the voltage amplitude swings of the signals, and to reduce noise modulation in the output video signal. A single synchronization signal is formed from the timing signals to accurately identify the last cell of a frame to be scanned, and to synchronize a row counter driving one of two flip-flops providing biphase array clock signals as the flip-flops have minimal pulse skew between complementary outputs, the effects of fixed pattern odd/even noise in the output video signal are substantially reduced. Further, the flip-flops uniquely provide large voltage amplitude swings without attendant heat generation problems.

Abstract: A line image or a line signature is optically scanned to generate digital signals for storage in an image matrix. These digital signals represent black and white cells defining the line signature or line image and are initially processed by tracing the image boundary. During the tracing a "thinning" or "peeling off" operation is performed that evaluates black cells in the image matrix for conversion into white cell digital signals. This thinning or peeling off process, also identified as data compression, continues until the line signature or line image is composed of a single cell thickness. The final phase of the data compression operation includes another boundary tracing of the one cell thick image, and connecting a sequence of boundary points defining each black cell to form a string of vectors which represent the signature. The resulting vector catalog comprises a composition of data including a vector starting point and vector directions which are encoded and stored for future retrieval.

Abstract: In the automatic processing of documents having bar encoded printing thereon, selectively variable error detection and correction codes are added to a bar encoded data field. Read errors which may occur from the reading of document data fields having overprints of inks of various types, colors and densities thereby may be substantially reduced. More particularly, either, neither or both a random parity code and a Bose-Chaudhuri-Hocquenghem (BCH) code may be added to a data message for a bar code printing to accommodate error correction and detection systems having differing processing capabilities. Further, the BCH code may be dynamically and selectively altered to accommodate both documents and data fields of varying lengths.

Abstract: To read characters printed on a document it is transported beneath a self-scan photocell array extending substantially the entire width of the document. Output signals from the photocells of the array are scanned by a plurality of channels, amplified and converted into a digital data format representing the character patterns. The digital data is then processed to memory electronics and search electronics to select lines of character pattern data for transmission to a character recognition unit. The search electronics compresses the character data into search segments to evaluate the top and bottom position of character lines. Further, the search electronics determines line linkages between the elements of one search segment of compressed data and the elements of the preceding search segments for future processing in a line tracker. The line tracker provides signals to extract character lines from a temporary storage for transmission to a line block memory.

Abstract: A method and system for recording information on a document surface to accommodate the automatic processing of documents is provided, which requires neither ink jet nor impact printing. A photosensitive material, such as a dye, is applied as a continuous coat over a field of the document surface. Selected locations within the field thereafter are irradiated with a light beam. The light beam is of an intensity and wavelength to effect a change in the light emitting properties of the photosensitive material at the selected locations. Either alphanumeric or bar encoded information may be recorded thereby on a document surface for subsequent detection by an optical reader.

Abstract: A valve system for selective control of flow of fluids from plural sources to a common conduit. Plural valves, are aligned along the conduit at different distances from a system axis. A cam array serves to selectively force the valves against a diaphragm to close off ports leading to the conduit upon rotation about the system axis.The invention is particularly suitable for use with a pressurized ink reservoir connected to one port, an ink solvent to a second port, and a drying gas to a third port. The valve system then may be rotated sequentially for initiating an ink operation, cleansing with the ink solvent, and drying with the gas without necessitating a disassembly of the system.

Abstract: A method and system for uniformly illuminating a field of information is provided for optical readers having a scanning device loosely constrained in movement. Lamps are symmetrically located about the optical axis of a sensor and enclosed within a four-sided illuminator. The sides of the illuminator converge at one end to a port having dimensions defined by the field to be viewed. A plate between the lamps and the sensor partially closes the second end of the illuminator, with an aperture therein symmetrical to the optical axis of the sensor. Internal wall portions of the illuminator adjacent to the reflecting plate are of a high diffuse reflectance, while portions adjacent to the port are of a low diffuse reflectance.

Abstract: Apparatus for attaching a nose section to the main body of a hand-held optical reader (Wand) is provided to accommodate the replacement of internal lamps illuminating a field of information. A nose attachment having a centrally located aperture encompassed by an integral and externally threaded cylindrical extension is secured to the nose section. The aperture and cylindrical extension are aligned and concentric with the optical image path of the Wand. In attaching the nose section to the Wand main body, the cylindrical extension is passed through an aperture in a partitioning frame of the Wand into which the lamps are seated. A screw-on cap, having a centrally located aperture with internal helical threads complementing the external threads of the nose attachment extension, is screwed onto the extension to secure the nose section to the partitioning frame. An outwardly extending flange integrally formed on the cap extends through opposing apertures of the Wand outer covers to accommodate access by hand.

Abstract: A stack of edge supported mail pieces delivered batchwise to a feed system requiring a continuous supply includes fingers moving the back of the stack with pressure responsive means in the fingers to discontinue the drive thereof when the pressure reaches a predetermined level.

Abstract: Printed bar codes which are either biphase modulated or bar-no-bar modulated are read as they pass an optical sensor. The video signal generated thereby is given a waveform having a constant reference level within an amplitude envelope of constant magnitude. The signal then is differentiated to provide a bipolar waveform having character dependent properties. The bipolar waveform is applied to a synchronizer to establish a digital synchronization waveform defining the time periods during which bar signals may occur. The bipolar waveform also is separated into positive and negative halves which are integrated separately and compared to a predetermined threshold to detect the presence of a bar. When a bar is present, the time of occurrence of the bar signal peak is correlated with the synchronization signal to identify either a logic one or a logic zero representation from the half-period position of the bar signal.