Abstract: A laser scanning system that employs synchronous time-division-multiplexed laser scanning operations and signal processing operations (for bar code detection). A plurality of successive non-overlapping time slots are defined and logically assigned to a unique laser scanning beam and corresponding photosensor. During a given time slot, the laser scanning beam logically assigned thereto is selectively generated (or selectively projected) into the scanning volume while generation (or projection) of the other laser scanning beam is disabled. Moreover, during the given time slot, the photosensor logically assigned thereto is operably coupled to signal processing circuitry that performs bar code detection operations on the data signals derived therefrom while the other photosensor is operably decoupled from such signal processing circuitry.

Abstract: A bioptical laser scanning system employing a plurality of laser scanning stations about a two independently controlled rotating polygonal mirrors. The system has an ultra -compact construction, ideally suited for space-constrained retail scanning environments, and generates a 3-D omnidirectional laser scanning pattern between the bottom and side-scanning windows during system operation. The laser scanning pattern of the present invention comprises a complex of quasi-orthogonal laser scanning planes, including a plurality of substantially-vertical laser scanning planes for reading bar code symbols having bar code elements (i.e. ladder type bar code symbols) that are oriented substantially horizontal with respect to the bottom-scanning window, and a plurality of substantially-horizontal laser scanning planes for reading bar code symbols having bar code elements (i.e. picket-fence type bar code symbols) that are oriented substantially vertical with respect to the bottom-scanning window.

Abstract: The effects of paper/substrate noise are significantly reduced in multi-focal zone laser scanning systems by processing analog scan data signals with a scan data signal processor having a plurality of pass-band filters and amplifiers that are automatically selected for passing only the spectral components of an analog scan data signal produced when a bar code symbol is scanned at a particular focal zone in the laser scanning system. Two or more different pass-band filter structures can be provided for use in the scan data signal processor, wherein each pass-band filter structure is tuned to the spectral band associated with a particular focal zone in the laser scanning system. When a bar code symbol is scanned by a laser beam focused within the first focal zone or scanning range of the system, the pass-band filter structure associated with this focal zone or scanning range is automatically switched into operation.

Abstract: A modular omnidirectional laser-based bar code symbol scanning system having at least one scan module insert that is removably disposed (e.g., removably installed) within a system housing (or portion thereof) through a service port (e.g., opening) in the system housing (or portion thereof). The scan module insert is a self-contained unit including at least the following components (in addition to mechanical support structures for such components): at least one laser diode, a rotating scanning element, an electric motor that rotates the rotating scanning element, one or more photodetectors, and analog signal processing circuitry that conditions (e.g., amplifies and/or filters out unwanted noise in) the electrical signal produced by the one or more photodetectors. The scan module insert can optionally include additional components including one or more light collecting optical elements, one or more beam folding mirrors, circuitry for detecting and decoding bar code symbols scanned by the system, etc.

Abstract: A bioptical laser scanning system employing a plurality of laser scanning stations about a two independently controlled rotating polygonal mirrors. The system has an ultra-compact construction, ideally suited for space-constrained retail scanning environments, and generates a 3-D omnidirectional laser scanning pattern between the bottom and side-scanning windows during system operation. The laser scanning pattern of the present invention comprises a complex of quasi-orthogonal laser scanning planes, including a plurality of substantially-vertical laser scanning planes for reading bar code symbols having bar code elements (i.e. ladder type bar code symbols) that are oriented substantially horizontal with respect to the bottom-scanning window, and a plurality of substantially-horizontal laser scanning planes for reading bar code symbols having bar code elements (i.e. picket-fence type bar code symbols) that are oriented substantially vertical with respect to the bottom-scanning window.

Abstract: A laser scanning system that employs synchronous time-division-multiplexed laser scanning operations and signal processing operations (for bar code detection). A plurality of successive non-overlapping time slots are defined and logically assigned to a unique laser scanning beam and corresponding photosensor. During a given time slot, the laser scanning beam logically assigned thereto is selectively generated (or selectively projected) into the scanning volume while generation (or projection) of the other laser scanning beam is disabled. Moreover, during the given time slot, the photosensor logically assigned thereto is operably coupled to signal processing circuitry that performs bar code detection operations on the data signals derived therefrom while the other photosensor is operably decoupled from such signal processing circuitry.

Abstract: A bioptical laser scanning system employing a plurality of laser scanning stations about a two independently controlled rotating polygonal mirrors. The system has an ultra-compact construction, ideally suited for space-constrained retail scanning environments, and generates a 3-D omnidirectional laser scanning pattern between the bottom and side-scanning windows during system operation. The laser scanning pattern of the present invention comprises a complex of quasi-orthogonal laser scanning planes, including a plurality of substantially-vertical laser scanning planes for reading bar code symbols having bar code elements (i.e. ladder type bar code symbols) that are oriented substantially horizontal with respect to the bottom-scanning window, and a plurality of substantially-horizontal laser scanning planes for reading bar code symbols having bar code elements (i.e. picket-fence type bar code symbols) that are oriented substantially vertical with respect to the bottom-scanning window.

Abstract: A laser scanning system that employs synchronous time-division-multiplexed laser scanning operations and signal processing operations. A plurality of successive non-overlapping time slots are defined and logically assigned to a unique laser scanning beam and corresponding photosensor. During a given time slot, the laser scanning beam logically assigned thereto is selectively generated (or selectively projected) into the scanning volume while generation (or projection) of the other laser scanning beam is disabled. During the given time slot, the photosensor logically assigned thereto is operably coupled to signal processing circuitry that performs bar code detection operations on the data signals derived therefrom while the other photosensor is operably decoupled from such signal processing circuitry.

Abstract: A laser scanning system including a multi-path scan data signal processor having multiple signal processing paths. Each signal processing path processes the same data signal (which is derived from the output of a photodetector) to detect bar code symbols therein and generate data representing the bar code symbols. And each signal processing path has different operational characteristics (such as low-pass filter cutoff frequencies, amplifier gain characteristics, and/or positive and negative signal thresholds). The varying operational characteristics of the signal processing paths are optimized to provide different signal processing functions (e.g., minimize paper noise, or maximize the scan resolution of the system). The data signal derived from laser scanning is supplied to each path of the multi-path scan data processor, where it is processed (preferably in parallel) to identify signal level transitions therein.

Abstract: A modular omnidirectional laser-based bar code symbol scanning system having at least one scan module insert that is removably disposed (e.g., removably installed) within a system housing (or portion thereof) through a service port (e.g., opening) in the system housing (or portion thereof). The scan module insert is a self-contained unit including at least the following components (in addition to mechanical support structures for such components): at least one laser diode, a rotating scanning element, an electric motor that rotates the rotating scanning element, one or more photodetectors, and analog signal processing circuitry that conditions (e.g., amplifies and/or filters out unwanted noise in) the electrical signal produced by the one or more photodetectors. The scan module insert can optionally include additional components including one or more light collecting optical elements, one or more beam folding mirrors, circuitry for detecting and decoding bar code symbols scanned by the system, etc.

Abstract: A modular omnidirectional laser-based bar code symbol scanning system having at least one scan module insert that is removably disposed (e.g., removably installed) within a system housing (or portion thereof) through a service port (e.g., opening) in the system housing (or portion thereof). The scan module insert is a self-contained unit including at least the following components (in addition to mechanical support structures for such components): at least one laser diode, a rotating scanning element, an electric motor that rotates the rotating scanning element, one or more photodetectors, and analog signal processing circuitry that conditions (e.g., amplifies and/or filters out unwanted noise in) the electrical signal produced by the one or more photodetectors. The scan module insert can optionally include additional components including one or more light collecting optical elements, one or more beam folding mirrors, circuitry for detecting and decoding bar code symbols scanned by the system, etc.

Abstract: A laser scanning system including a multi-path scan data signal processor having multiple signal processing paths. Each signal processing path processes the same data signal (which is derived from the output of a photodetector) to detect bar code symbols therein and generate data representing the bar code symbols. And each signal processing path has different operational characteristics (such as low-pass filter cutoff frequencies, amplifier gain characteristics, and/or positive and negative signal thresholds). The varying operational characteristics of the signal processing paths are optimized to provide different signal processing functions (e.g., minimize paper noise, or maximize the scan resolution of the system). The data signal derived from laser scanning is supplied to each path of the multi-path scan data processor, where it is processed (preferably in parallel) to identify signal level transitions therein.

Abstract: A bioptical laser scanning system employing a plurality of laser scanning stations about a two independently controlled rotating polygonal mirrors. The system has an ultra-compact construction, ideally suited for space-constrained retail scanning environments, and generates a 3-D omnidirectional laser scanning pattern between the bottom and side-scanning windows during system operation. The laser scanning pattern of the present invention comprises a complex of quasi-orthogonal laser scanning planes, including a plurality of substantially-vertical laser scanning planes for reading bar code symbols having bar code elements (i.e. ladder type bar code symbols) that are oriented substantially horizontal with respect to the bottom-scanning window, and a plurality of substantially-horizontal laser scanning planes for reading bar code symbols having bar code elements (i.e. picket-fence type bar code symbols) that are oriented substantially vertical with respect to the bottom-scanning window.

Abstract: The effects of paper/substrate noise are significantly reduced in multi-focal zone laser scanning systems by processing analog scan data signals with a scan data signal processor having a plurality of pass-band filters and amplifiers that are automatically selected for passing only the spectral components of an analog scan data signal produced when a bar code symbol is scanned at a particular focal zone in the laser scanning system. Two or more different pass-band filter structures can be provided for use in the scan data signal processor, wherein each pass-band filter structure is tuned to the spectral band associated with a particular focal zone in the laser scanning system. When a bar code symbol is scanned by a laser beam focused within the first focal zone or scanning range of the system, the pass-band filter structure associated with this focal zone or scanning range is automatically switched into operation.

Abstract: A modular omnidirectional laser-based bar code symbol scanning system having at least one scan module insert that is removably disposed (e.g., removably installed) within a system housing (or portion thereof) through a service port (e.g., opening) in the system housing (or portion thereof). The scan module insert is a self-contained unit including at least the following components (in addition to mechanical support structures for such components): at least one laser diode, a rotating scanning element, an electric motor that rotates the rotating scanning element, one or more photodetectors, and analog signal processing circuitry that conditions (e.g., amplifies and/or filters out unwanted noise in) the electrical signal produced by the one or more photodetectors. The scan module insert can optionally include additional components including one or more light collecting optical elements, one or more beam folding mirrors, circuitry for detecting and decoding bar code symbols scanned by the system, etc.

Abstract: A laser scanning system that employs synchronous time-division-multiplexed laser scanning operations and signal processing operations (for bar code detection). A plurality of successive non-overlapping time slots are defined and logically assigned to a unique laser scanning beam and corresponding photosensor. During a given time slot, the laser scanning beam logically assigned thereto is selectively generated (or selectively projected) into the scanning volume while generation (or projection) of the other laser scanning beam is disabled. Moreover, during the given time slot, the photosensor logically assigned thereto is operably coupled to signal processing circuitry that performs bar code detection operations on the data signals derived therefrom while the other photosensor is operably decoupled from such signal processing circuitry.

Abstract: The zone laser scanning systems by processing analog scan data signals with a scan data signal processor having a plurality of pass-band filters and amplifiers that are automatically selected for passing only the spectral components of an analog scan data signal produced when a bar code symbol is scanned at a particular focal zone in the laser scanning system. Two or more different pass band filter structures can be provided for use in the scan data signal processor, wherein each pass-band filter structure is: tuned to the spectral band associated with a particular focal zone in the laser scanning system. When a bar code, symbol is scanned by a laser beam focused within the first focal zone or scanning range of the system, the pass-band filter structure associated with this focal zone or scanning range is automatically switched into operation using a control signal produced by determining the spot speed of the laser scanning beam producing the analog scan data signal being processed.

Abstract: A multi-focal zone laser scanning system for scanning bar code symbols having a minimum bar element width (MBW). The multi-focal zone laser scanning system comprises a laser beam producing device for producing a laser beam, and a laser beam scanning mechanism for scanning the laser beam so as to generate a laser scanning pattern having a plurality of different focal zones. In the system, the scanned laser beam has a minimum beam dimension (MBD) with each focal zone, and the ratio of the minimum beam dimension (MDB) within each focal zone to the minimum bar element width (MBW) of a scanned bar code symbol therewithin (i.e. MDB/MBW) is greater than or equal to 2.0. Consequently, less modulation of the laser scanning beam is required during scanning operations, and therefore, bar code symbols having narrower minimum bar element widths can be resolved.

Abstract: A scan data signal processor is disclosed for use with a laser scanning system having a plurality of different focal zones within which a laser scanning beam is scanned across one or more bar code symbols and an analog scan data signal is automatically produced. The scan data signal processor comprises a first and second derivative signal generation stages, a second-derivative zero-crossing detector, a real-time bar code element detector, and a control logic circuitry. The first derivative signal generation stage derives a first derivative signal from the analog scan data signal. The second derivative signal generation stage derives a second derivative signal from the first derivative signal. The second-derivative zero-crossing detector detects zero crossings in said second derivative signal. The real-time bar code element detector automatically detects the presence and absence of bar code element data encoded within said analog scan data signal.

Abstract: A laser scanning system including a multi-path scan data signal processor having multiple signal processing paths. Each signal processing path processes the same data signal (which is derived from the output of a photodetector) to detect bar code symbols therein and generate data representing the bar code symbols. And each signal processing path has different operational characteristics (such as low-pass filter cutoff frequencies, amplifier gain characteristics, and/or positive and negative signal thresholds). The varying operational characteristics of the signal processing paths are optimized to provide different signal processing functions (e.g., minimize paper noise, or maximize the scan resolution of the system). The data signal derived from laser scanning is supplied to each path of the multi-path scan data processor, where it is processed (preferably in parallel) to identify signal level transitions therein.