Abstract: Machine readable fragments of a code pattern that is parameterized in N-dimensional space, where N.gtoreq.2, are affixed to two or three dimensional physical objects, such that the objects are uniquely identified by the addresses of the machine readable address space fragments affixed thereto.

Abstract: A method and apparatus for quasi-reprographically replicating a source document. The source document is digitized, appropriate locations for embedded code are detected, and any embedded code located in the digitized document along with the detected locations are forwarded to a decoder. The decoder forwards the decoded information to a control unit which processes this information and forwards it to a encoder whereafter it is inserted in the digitized document. The hardcopy replication of the source document being substantially visually identical to the source document, even though new or additional embedded machine-readable data has been added or existing data has been changed. The process occurs without intervention by an operator and without knowledge of the operator producing the replicated documents.

Abstract: A code pattern such as a self-clocking glyph code pattern is parameterized in at least three dimensions by parallel propagating, unique numeric sequences.

Abstract: A code pattern, such as a glyph code pattern, is parameterized in two-dimensional space by encodings of parallel propagating unique numeric sequence which incrementally vary in phase transversely of the code pattern.

Abstract: To facilitate the recovery data from an embedded data pattern through the use of a appropriately sized capture window that is randomly positioned within the data pattern, the embedded data pattern is composed of a plurality of identical, one dimensionally or two dimensionally regularly tiled embedded data blocks which contain sufficient spatial addressing information to permit the logical reconstruction of a complete data block from any set of fragments that collectively provide a full cover for the surface area of any one tile. To this end, the capture window is sized to include a shape which is completely registered with the data pattern in which is capable of tiling the recording medium in accordance with the tiling vectors.

Abstract: A method of achieving optimum optical contrast for detecting registration marks in a multicolor electrophotographic printing machine. The reflectivity of the image carrying member which is usually an intermediate transfer belt is determined. The reflectivity of each of the toners is then determined. If one of the toners has a contrasting reflectivity, while the remaining toners do not contrast then a uniform field of the contrasting toner is imaged and developed and the registration marks for the other toner colors are then developed on top of the uniform field. A void in the field in the shape of the other toner marks is used as the registration mark for the contrasting toner. If all of the toners have a contrasting reflectivity with the belt, the registration marks are imaged and developed directly on the belt.

Abstract: An image forming apparatus and method use interlace scanning of plural light beams by deflecting the plural beams with a rotating polygon onto a recording medium. Corrections are made to the scan envelope to compensate for errors due to perceived imperfections in the spot profile or aberrations in the optical and mechanical systems used to scan the spot. The corrections are performed by adjusting intensity of gaussian components of the envelope according to a look up table.

Abstract: Self-clocking glyph codes encode interleaved or interlaced codes to facilitate the partitioning and correlation of data embedded within such glyph codes.

Abstract: An optically readable record for storing encoded information comprises (1) a recording medium, (2) a self-clocking data code for encoding the information, with this data code being composed of glyphs that are written in a two dimensional code field on the recording medium on centers that are spatially distributed in nominal accordance with a predetermined spatial formatting rule, where the glyphs are defined by respective symbols that are selected from a finite set of optically discriminable symbols to encode the information, and (3) a self-clocking synchronization code pattern that is written on the recording medium to fully frame at least a portion of the data code, with this the synchronization code pattern defining multiple paths of self-clocking glyphs for reaching any given glyph of synchronization code pattern from any other glyph thereof.

Abstract: Machine readable electronic domain definitions of part or all of the electronic domain descriptions of hardcopy documents and/or of part or all of the transforms that are performed to produce and reproduce such hardcopies documents are encoded in codes that are printed on such documents, thereby permitting the electronic domain descriptions of such documents and/or such transforms to be recovered more robustly and reliably when the information carried by such documents is transformed from the hardcopy domain to the electronic domain.

Abstract: An optically readable record for storing encoded information comprises (1) a recording medium, (2) a self-clocking data code for encoding the information, with this data code being composed of glyphs that are written in a bounded two dimensional code field on the recording medium on centers that are spatially distributed in nominal accordance with a predetermined spatial formatting rule, and the glyphs being defined by respective symbols that are selected from a finite set of optically discriminable symbols to encode the information, and (3) a self-clocking address pattern written on the recording medium to extend across the code field along at least one axis, with this address pattern being composed of a unique glyph pattern that disambiguates spatial position within the address pattern to a subpattern precision.

Abstract: A self-clocking glyph code is composed of data glyphs which encode logically ordered data values, together with one or more multi-glyph synchronization code patterns. Each of the synchronization code patterns is distinguishable from the data glyphs, but the synchronization code pattern or patterns provide an explicit spatial reference for the data glyphs. To this end, the glyphs of the synchronization code pattern or patterns are written on the recording medium in accordance with the same spatial formatting rule as the data glyphs, plus at least one additional formatting rule that establishes a predetermined geometric relationship between the glyphs of the synchronization code pattern or patterns and corresponding ones of the spatially formatted data glyphs, such that the logical order of at least a significant number (>>1) of the data glyphs is inferable from the synchronization code pattern or patterns.

Abstract: An optically readable record for storing encoded information comprises (1) a recording medium, (2) a self-clocking data code for encoding the information, with this data code being composed of glyphs that are written in a two dimensional code field on the recording medium on centers that are spatially distributed in nominal accordance with a predetermined spatial formatting rule, where the glyphs are defined by respective symbols that are selected from a finite set of optically discriminable symbols to encode the information, and (3) at least one additional glyph pattern that is written on said recording medium in nominal accordance with the spatial formatting rule, the additional code pattern providing physical addressing information for random access from any given location within the glyph pattern to any other given location within the same glyph pattern or another glyph pattern on the same or a differnt recording medium.

Abstract: A process for the authentication of documents which comprises generating developed documents in an electophotographic apparatus, or in a laser printer with an encapsulated toner comprised of a core comprised of polymer, an optional pigment, and an infrared emitting component, and thereover a polymeric shell; and subjecting the document to an infrared reader whereby the infrared component is detected spectroscopically.

Abstract: A technique for reducing interpixel crosstalk in an electrooptic total internal reflection light modulator image bar. A particular electrode length is selected to tailor a portion of the spatial frequency response of the image bar. The pixel size and quality resulting from a voltage difference between electrodes are determined primarily by the overall image bar spatial frequency response, and a set of preferred physical parameters can be determined by selecting parameter values to provide the desired spatial frequency response. It has been found that a desirable frequency response is one that approximates sin(.pi.Pf) for absolute values of f less than about 1/P, where f is the spatial frequency and P is the minimum pixel pitch. Further, it has been found that a particular electrode length provides the desired response for small absolute values of f. The particular electrode length is approximately E.sup.1/2 P/.gamma.

Abstract: The glyphs of a self-clocking glyph code for encoding n-bit long multi-bit digital values are preordered in a cyclical sequence, based on their analytically or empirically determined probabilities of being confused with each other, such that each glyph is adjacent in that sequence to the two glyphs with which it is more likely to be confused during decoding. Binary encoding values then are assigned to these ordered glyphs in accordance with an n-bit long Gray code sequence, so that the value assigned to any given glyph differs in just one bit position from the values assigned to the glyphs with which it is most likely to be confused.

Abstract: A technique for reducing interpixel crosstalk by selecting particular illumination conditions and thus tailoring a portion of the spatial frequency response of an optical image bar. A desirable frequency response is one that approximates sin(.pi.Pf) for absolute values of f less than about 1/P, where f is the spatial frequency and P is the minimum pixel pitch. A skew angle of zero and a grazing angle that is approximately twice the interorder diffraction angle provides the desired cutoff of the response for absolute values of f above about 1/P. The desired frequency response for absolute values of f near zero can be achieved by selecting appropriate values for other physical parameters.

Abstract: The electrooptic internal reflection modulator of the present invention provides a technique for reducing interpixel crosstalk by using a compensation filter to help define the spatial frequency response of an image bar. The diffraction efficiency of the system is in part defined by a set of properties of the modulator, the illumination and the imaging subsystems, and is characterized by a spatial frequency response. It has been found that a desirable frequency response is one that approximates sin(.pi.Pf) for absolute values of f less then 1/P, where f is the spatial frequency and P is the minimum pixel pitch.

Abstract: Increasing the addressing capability of an optical image bar having a particular pixel center-to-center spacing (pixel pitch) is accomplished by employing a plurality of N electrodes per pixel. Compared to an optical image bar with one electrode per pixel, this provides N times as many locations for the electric potential transition which establishes the center of the pixel. The provision of multiple electrodes per pixel interval can be used to implement interlacing.

Abstract: Microaddressable printers and other types of display systems are provided for rendering two dimensional images on high gamma, photosensitive recording media. These systems are microaddressable because they are operated in an overscanned mode to render images by scanning one or more intensity modulated scan spots over a high gamma, photosensitive recording medium in accordance with a scan pattern that causes the spot or spots to superimpose multiple discrete exposures on the recording medium on centers that are separated by a pitch distance that is significantly less than the effective spatial diameter of the scan spot or spots (e.g., the full width/half max. diameter of a gaussian scan spot). Overscanned systems have substantially linear addressability responses, so boundary scans that are intensity modulated in accordance with preselected offset values are used by these systems for spatially positioning the transitions that are contained by the images they render to a sub-pitch precision.