Abstract: A method and apparatus for reading encoded symbols such as bar code labels at any orientation to a raster scanning device. A pattern of virtual scan lines is selected over the two-dimensional imaging region according to the specifications of the images to be read. The pattern is generated by defining a family of parallel lines of a certain spacing and rotating the family by a specified angle until the two-dimensional imaging region is covered. Only the data at selected raster locations on the virtual scan lines is stored and processed. One-dimensional signal processing methods are used to detect edges and decode the encoded symbols.

Abstract: A scanner window through which a laser beam is projected to define a scanning pattern comprises a substrate formed of light transmissive material which allows the laser beam to project through a light transmissive hard material layer deposited onto the substrate, and a light transmissive lubricous coating deposited onto the hard material resulting in the scanner window having improved resistance to abrasive wear. The present invention is also directed to a method of producing such a scanner window. The present method may incorporate various deposition techniques to form a wear resistant scanner window in accordance with the present invention.

Abstract: An optical system and method for data reading having a light source which generates an optical beam directed toward an object to be read and a focusing system in the outgoing light path which establishes multiple beam functions. In a preferred application, a scanning system includes a multifocal lens having a single lens element having an inner lens portion of a first focal length and an outer annular lens portion with a second focal length, the optical system of a bar code scanner therefore establishing two separate focal positions from a single light source. Alternately, the system includes a focusing lens system with an corrector element disposed in the outgoing optical path, the corrector element having a plurality of optical zones, each zone having a different optical characteristic for modifying a portion of the outgoing optical beam. A zone may be a refractive region, a reflective region, a diffractive region, an empty region, a window region, or combinations thereof.

Abstract: An interface selection and configuration system for a computer peripheral in which configuration for the peripheral and/or the host interface is at least in part accomplished by the interface connector cable. In a preferred embodiment, the computer peripheral is equipped with one or more hardware interfaces. The interface connector cable has a first end connector for attaching to the computer peripheral. The first end connector of the interface connector cable is typically a multiple pin connector constructed and arranged to be properly physically and electrically connectable only to a specific computer peripheral or class of computer peripherals, the first end connector including at least one electrical connection between two pins for completing a circuit within the computer peripheral thereby enabling the computer peripheral.

Abstract: A lens configuration integral with the output window of an enclosure at least partly surrounding a source of a beam is provided. In one embodiment, the beam is an anomorphic diverging beam, such as that produced by a diode laser, having differing angles of divergence along parallel and perpendicular axes, and the at least one lens is configured to at least partly equalize the angles of divergence along the perpendicular and parallel axes.

Abstract: In an optical scanning system, a method and apparatus for decoding labels of single or multiple block formats by stitching together partial label segments obtained from multiple optical scans across the label is provided. Partial scans are decoded into strings of character information which are assembled by locating sub-strings of common elements between two strings. Strings in which the common elements occur at the ends are merged by deleting one set of redundant common characters and joining the remaining characters in proper sequence. The method assembles strings in which the common elements occur in the middle of one or both strings by testing for valid string combinations made by deleting characters adjacent to the common sub-string, on opposing ends of each string, and merging the resulting strings. Feature characters, parity information, checksum digits, and other label structural characteristics are used to verify resulting strings and completed blocks and labels.

Abstract: A bar code scanning system such as for use in retail checkout in which the scanning system has a conveyor defining a first surface and a second surface disposed adjacent the first surface and arranged generally orthogonally thereto forming a scan volume therebetween; sets of pattern mirrors positioned adjacent the respective surfaces; and one or more laser beam sources associated with a rotating mirror polygon for producing scan patterns which are routed to the pattern mirrors and out through the respective surfaces into the scan volume.

Abstract: A method and apparatus for increasing the speed of scanners reading multiple bar code symbologies by changing the order of priority in which the various symbologies are tested by the decoder. After a particular symbology has been read a given number of times in a row, its priority is increased. A particular symbology will continue to advance in priority the more often it is read until it becomes the highest priority symbology.

Abstract: An optical system and method for data reading in which a light source generates an optical beam directed toward an object to be read and a variable aperture mechanism positioned in the outgoing light path establishes at least two separate focal planes. The variable aperture device may comprise a variable aperture system in which the size of the aperture is selectively varied about a range within the diffractive limit of the light beam. A preferred aperture mechanism is a liquid crystal aperture with one or more aperture regions which are selectively or consecutively activated. The optical system therefore establishes two or more separate waist locations from a single light source resulting in greater depth of field or multiple depths of field.

Abstract: An optical system and method for data reading. The preferred system is directed to a scanner which includes a multiple beam service, such as a laser diode and a beam splitter which generates first optical beam and a second optical beam, the first optical beam being directed toward one side of a scanning optical element such as a rotating polygon mirror and to a first mirror array, the second optical beam is being simultaneously directed toward a second optical element such as another side of the rotating polygon mirror and then to a second and a third mirror array. The first mirror array is configured to generate a scan pattern through a vertical window and the second and third mirror arrays are configured to generate scan patterns passing through a horizontal window. In combination, the three mirror arrays generate three sets of scan lines so as to scan the bottom and all lateral sides of an object being passed through the scan volume.

Abstract: A laser bar code system is described which includes a first scan module releasably affixed to a housing, which scan module is readily interchangeable with and plug compatible with a second scan module which is configured at least partly differently from the first scan module. In addition, a partitioned scan module is described which comprises a first laser diode subsystem, a first scanning subsystem, a first collection subsystem, and a first signal processing subsystem, a selected one of which is releasably affixed to a chassis, and readily interchangeable and plug compatible with a second laser diode subsystem, a second scanning subsystem, a first collection subsystem, and a second signal processing subsystem, respectively, which is configured at least partly differently from the first.

Abstract: A method and apparatus for determining the transitions between binary levels of an input signal such as a scanned bar code label by detecting zero crossings of an approximated second derivative of the input signal. Samples of the input signal are obtained by using delay lines, sample-and-hold circuits, an analog shift register or similar device. The first derivative of the signal is approximated by the slope of a straight line between two sampled points on the waveform. The second derivative is approximated by the difference between two first derivatives. Zero crossings of the second derivative indicating transitions of the input signal may be determined either by detecting a signal peak on both sides of the zero crossing, or by comparing the second derivative signal to zero when the first derivative exceeds a positive or negative threshold. The time between sample points may be adjusted to match a particular range setting of a scanner having a plurality of range settings.

Abstract: A method and apparatus for reading encoded symbols such as bar code labels at any orientation to a raster scanning device. A pattern of virtual scan lines is selected over the two-dimensional imaging region according to the specifications of the images to be read. The pattern is generated by defining a family of parallel lines of a certain spacing and rotating the family by a specified angle until the two-dimensional imaging region is covered. Only the data at selected raster locations on the virtual scan lines is stored and processed. One-dimensional signal processing methods are used to detect edges and decode the encoded symbols.

Abstract: A method and an apparatus facilitate scanning an Add-On code portion of a bar code label to determine the bar code data printed thereon by sweeping a scanning beam in a scan path across the Add-On code portion of the label. The bar code label includes bar codes of the type which have a primary code portion and which may also have an Add-On code portion.

Abstract: An optical system and method for data reading having a light source which generates an optical beam directed toward an object to be read and a focusing system in the outgoing light path which establishes multiple beam functions. In a preferred application, a scanning system includes a multifocal lens having a single lens element having an inner lens portion of a first focal length and an outer annular lens portion with a second focal length, the scanning system therefore establishing two separate focal positions from a single light source. Alternately, the system includes a focusing lens system with an corrector element disposed in the outgoing optical path, the corrector element having a plurality of optical zones, each zone having a different optical characteristic for modifying a portion of the outgoing optical beam. A zone may be a refractive region, a reflective region, a diffractive region, an empty region, a window region, or combinations thereof.

Abstract: A data gathering system including a scanner and scale including one or more of the following features: a construction of compact dimensions with a low profile; integrated construction of the locations of the scanner and scale, and their associated components; modular components that are easily detachable and serviced; a rigid casing which is integrated into the overall data gathering system and which prevents a countertop from contacting the scale; and diagnostic capability incorporated into the data gathering system.

Abstract: A method and apparatus for holding an otherwise variable parameter in a scanner approximately constant over a desired scan volume to improve the ability to compensate for unwanted variations in the amplitude modulation depth of a signal is provided, the signal being determined from collected light reflected from a target. In one embodiment, the time domain impulse response of the opto-mechanical system is the parameter which is held approximately constant by appropriately positioning the beam waist so that the beam spot size diverges approximately linearly along the beam axis within the scan volume.

Abstract: A point of sale (POS) bar code scanner such as in common use in retail stores includes provision for reading bar coded redemption coupons (or other bar coded documents redeemable for value) in a manner secure from a human operator. Integration of functions between the POS scanner and the coupon reader varies with different embodiments described. Through software associated with bar code decoding logic, a comparison is made between information on a validation coupon and information on items presented for purchase, and a decision is made as to whether the redemption coupon is valid and redeemable in this transaction. In one embodiment, the bar code scanner simply receives the redemption coupon face down on the product scanner window, and integrated decode logic of the scanner identifies the bar code as belonging to a redemption coupon, then makes the comparison and validation of the coupon for the particular transaction.