Abstract: A circuit is shown for use with a bar code scanner wherein the scanner includes a laser for producing a beam of light that is scanned across the bar code so that the light reflected from the bar code may be focused upon a sensor which produces an electrical signal representing the bar code. Scanning is stopped by a first circuit after a predetermined number of scans. Thereafter, a second circuit completes the decoding of the electrical signal and outputs the results if that decoding is successful. If not, a third circuit restarts the scanning within the first circuit.

Abstract: This is a cutter assembly for linerless strip media having an uncovered adhesive backing. There is a cutter mounted for transverse movement across the media and a backing bar with at least two cutting edges. The backing bar can be rotated to place one of the cutting edges in position to cooperate with the cutter to cut the media. The backing bar is rotatable about a transverse axis simultaneously with feed movement of the media at a rotational speed equal to the feed speed of the media. This causes the media to ride up on a pointed portion of a cutting edge without dragging across the cutting edge as the cutting edge moves into a use position in which the media is supported by a support surface of the cutting edge. A cleaning station cleans the previously used cutting edge as the bar is rotated. Rotating and fixed cutters can be used. The cutter is replaceable and can be supplied in combination with an associated media for which it is designed.

Abstract: The new bar code symbology under the present invention directly encodes one symbol character for each human readable character in known 16-bit data character encoding standards, such as Unicode. The symbology employs six bars and six spaces for each symbol, and has a total width of 21 modules for each symbol character, and thus is a (21,6) symbology. Bars and spaces in symbol characters having greater than six modules in width are eliminated, as are bounding strings of more than six adjacent one-wide elements. As a result, the symbology is wand scannable, readily printable, and can be read when out-of-focus. Parity codes are employed, to enable Hamming distances between symbol characters to be maximized, and thereby improve data security of the symbology (e.g., the total width of all bars in each symbol character is equal to an even number). As a result, the present symbology preferably encodes 80,077 data characters.

Abstract: An apparatus and method for imaging low contrast one and two-dimensional symbols are provided. A light source directs light onto a target that includes a low contrast symbol. An imaging element receives light reflected off of the target and creates an image of the target therefrom. A light level detector determines the intensity level of the light received by the imaging element, and when the intensity level exceeds a predetermined threshold, a controller causes the image data created by the imaging element to be stored in a data memory.

Abstract: A method and apparatus locates multiple "bounding boxes" within an image of a symbol located within an image stored by a reader. The symbol preferably has a recognition pattern with an longitudinally extending bar and at least one vertically extending reference bar, such as in the Code One symbology. The method locates the positions of landmark points within the stored image. Landmark points include points at the end of the longitudinally extending bar, points at the corner or root formed between the longitudinally extending bar and the vertically extending bar, points at the ends of the vertically extending bars, and points at the intersection between the bars and blocks that extend transversely therefrom. Based on the locations of the landmark points, horizontal and vertical line functions are defined between collinear landmark points. Based on the intersection of the line functions, multiple bounding boxes are constructed to determine the periphery and all data areas of the symbol within the stored image.

Abstract: A label printer having a stepping motor and the ability to dynamically accurately control longitudinal label registration as a function of steps of the stepping motor. The effective length of the steps moving the labels between a known point prior to the printhead and the printhead are monitored and the number of steps actually used to move the labels between the known point and the printhead are adjusted as a function of changes in the effective step length. In one embodiment, a sensor counts the steps between consecutive labels or averages a number of labels to determine the effective step length. In another embodiment, a sensor detects the start of label and start of printing on the label and the step distance between the two is used to determine the effective step length.

Abstract: Linerless media for labels is visibly or invisibly marked along its length with marks or small holes to indicate motion marks and/or position marks related to pre-printed label information. The marks are used to properly position pre-printed label information with respect to a printer printhead. The marks can also be used to detect critical speeds of the media that can cause problems such as standing waves or poor print quality from the printhead. The marks are also used to position and print on linerless media being pulled by hand through a printer having no drive motor.

Abstract: Disclosed is apparatus for scanning a field of view for two-dimensional data and for rapidly processing the data. There is a video device viewing the field of view and producing a two-dimensional matrix of pixel data as an output representing a plurality of pixel positions of the field of view. A digital memory receives and holds the two-dimensional matrix of pixel data output from the video device in a plurality of multiple pixel data words. There is also a digital processor including a register for receiving pixel data and logic for processing data to decode it. Primarily, there is pixelizer logic and associated circuitry connected between the digital memory and the digital processor for removing data associated with a specified pixel position within the field of view from an associated one of the plurality of multiple pixel data words in the digital memory and for placing the data into a pre-established bit position within the register of the digital processor.

Abstract: A method and apparatus for decoding profiles which fail to resolve narrow elements in machine-readable symbols formed as relief patterns, first begins by identifying which elements in the profile are resolved. Second, the distances between the centers of the resolved elements are determined. Third, closure boundaries are determined, and the widths of resolved elements are determined at the closure boundary. The type of resolved element is determined based on its measured width. Thereafter, a unit distance is determined for 1-wide narrow elements unresolved in the profile. Based on the unit distance and the width of two adjacent resolved elements, a matrix is constructed for determining the number of narrow elements unresolved between two resolved elements. Based on the measured center distances, the resolved element widths and the matrix, all of the unresolved narrow elements are identified in the profile and the profile is subsequently decoded.

Abstract: A method and apparatus for locating and decoding machine-readable symbols is provided. The present invention stores an image of the symbol and locates all Jordan curves having an angular length less than .pi. within the image of the symbol. The present invention finds and selects all convex Jordan curves from the set of all Jordan curves found within the stored image. The present invention determines equations of a pair of tangent lines from end points of each convex Jordan curve and determines an equation of a center line for each pair of tangent lines. The present invention determines a point of intersection of the center lines, and based on the point of intersection, locates a center point of a finder pattern of the symbol. The present invention confirms that the located center point is indeed the center of the finder pattern, and thereafter decodes the symbol.

Abstract: A method and apparatus for locating and decoding machine-readable symbols is provided. In a preferred embodiment, an image of the symbol is stored and a sampling path through the stored image is selected. The sampling path represents a reflectance signal profile formed through the symbol. Characteristic or critical points are selected along the profile, including minimum and maximum points of peaks and valleys in the profile. Distances between the centers of peaks and valleys are determined. The present invention locates a defined portion of the symbol, such as a finder pattern, by locating a predetermined series of measured distances, such as a series of adjacent, substantially equal distances. After having located the finder pattern, the present invention determines the location of the symbol within the stored image, and thereafter decodes the symbol.

Abstract: A bar code imaging system provides increased resolution for accurately interpreting width modulated bar code symbols. The bar code imaging system comprises an imaging element adapted to receive light reflected from a bar code symbol and provide a two-dimensional image of the bar code symbol. The two-dimensional image is decoded into data representative of the bar code symbol. More particularly, the spacing between adjacent bar elements and adjacent space elements of said bar code symbol is measured by sampling along a diagonal line segment that intersects the adjacent bar elements. The diagonal sampling allows a greater number of pixels to be included in the measurement. If necessary, a perpendicular spacing measurement can be derived from the diagonal measurement.

Abstract: A bar code imaging system capable of accurately and efficiently reading a printed bar code that is partially damaged, distorted, or erased. The bar code imaging system comprises an imaging element adapted to receive light reflected from a bar code symbol and provide a two-dimensional image of the bar code symbol. The two-dimensional image is decoded into data representative of the bar code symbol. More particularly, code words in the bar code pattern are decoded along a path beginning at the start of the bar code and moving toward the end of the bar code. As each code word is decoded, the decoded data is stored in a memory. When an invalid code word is encountered, decoding continues along a path beginning at the end of the bar code and moving toward the beginning of the bar code, and the decoded data is stored in the memory with the previously decoded data.

Abstract: An on-demand narrow web electrophotographic printer and method of printing forms a latent image and a narrow web paper feeding mechanism feeds paper from a roll for closely spaced printouts of tickets or labels, such as adhesive-backed labels, for bar codes, receipts of arbitrary length, or lottery tickets. An endless rotary latent image carrier mechanism and cutter blade are synchronized with a paper infeed mechanism, a fixing unit, and an outfeed to feed, print and cut the paper printout at a controlled length and with no paper wastage. In different embodiments, a length of paper is either accumulated in advance or drawn back to a position ahead of the drum to allow on-demand operation without sacrificing printing efficiency.

Abstract: A method and associated apparatus for printing font character bars comprised of a plurality of rows which are in turn comprised of a plurality of close adjacent dots to improve print quality and readability thereof by optical reading apparatus while increasing potential print speeds. The basic method comprises removing a portion of one dot or more from an end of each of the plurality of rows of a character bar which is too wide for optimal reading by optical reading apparatus. Alternative methods and apparatus for automatically adjusting the fonts and printing temperature of a thermal printhead as a function of system parameters are also disclosed.

Abstract: An electro-optical imaging system that utilizes an efficient search algorithm to find a coded symbol within a digitized image is provided. A digitized image of an area of an object having a coded symbol attached or printed thereon is created and stored in an image memory. A search algorithm is then activated to search for the coded symbol within the digitized image stored in the image memory. The search is limited to an area of the digitized image that is defined by boundary parameters. The search begins with the scan of an initial horizontal line of pixels that passes through the center of the search area, and an initial vertical line of pixels that also passes through the center of the search area. Subsequent horizontal and vertical lines of pixels are then scanned, one each subsequent line is located an integer multiple number of step sizes from one of the initial lines.

Abstract: A coded symbol encoding and decoding system and method provides improved efficiency and security by compressing and/or encrypting data prior to encoding the data into a coded symbol symbology. Prior to encoding the data into the coded symbol symbology, the encoding portion of the system compresses and/or encrypts the data. If compression decreases the size of the data by a given threshold, the system encodes the compressed data. Otherwise, the system encodes the uncompressed data. An unused character in the encoded data is used as a flag to indicate whether the data was compressed and/or encrypted. The encoded data is then printed as a coded symbol pattern. Conversely, the decoding portion reads the printed pattern, decodes the resulting data, and if necessary, decompresses and/or decrypts the data. Use of an unused character in the encoded data to indicate whether the data was compressed and/or encrypted allows the system and method to be used with existing symbologies.

Abstract: A printer for printing on an outer layer of a print medium on a print medium roll. The printer may use thermal or inkjet printing. The printer is used without a mechanical paper drive mechanism. The printer monitors movement of an outer wrap of the print medium as the print medium roll rotates in response to a user pulling print medium from the print medium roll. In one embodiment, the printer detects movement of the print medium with a metering roller and an optical rotation sensor. In another embodiment, the printer monitors movement of the print medium by detecting movement of index marks on the print medium. From the monitored movement of the print medium, the printer identifies a portion of the print medium aligned to the printhead and selects image portions to print in the identified portion. The printer then activates the printhead to print the selected image portions in the corresponding identified portion.