Abstract: A bar code reader includes a first and second memory arrangement in which a two dimensional image containing the image of a bar code symbol at a random location and orientation is stored in a first memory. Thereafter, the contents of the first memory is processed by a specialized controller to determine whether any portion of the stored image is likely to contain a bar code symbol, and if so, at what location. If a bar code symbol is located, then the portion of the image stored in the first memory which has been identified as likely to contain a bar code symbol is transferred to a second memory. In the second memory, the stored image is processed by a digital signal processor in order to orient, filter and scan the stored bar code image.

Abstract: Optical scanning of one- and two-dimensional barcode symbols is carried out first in an aim mode wherein the symbol is scanned using a first scan pattern that is relatively small and dense so as to be visible to the user and thereafter using a second, larger and more robust scan pattern for decoding. During aiming, the symbol is partially decoded to determine type and orientation, and this information is applied to control the angle of the scan pattern produced, the rate at which the scan pattern is increased for optimum decoding, and the ultimate pattern size. Preferred scan patterns, as well as unique scan mechanisms, are described.

Abstract: The present invention relates to an ambient light detector, a laser lighting control device using the same suitable for a bar code reader, and a bar code reader. The object is to require no explanation on a special operation and to realize an easy device design and a low manufacturing cost. Each device includes an ambient light detector to detect light around a peripheral device, and judging device to provide a signal indicating that an ambient light detected by the ambient light detector has exceeded a predetermined value over a predetermined time.

Abstract: A method and apparatus for decoding profiles which fail to resolve narrow elements in multi-width symbols, 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: Random partial scans of a bar code label are utilized to re-create the entire symbol. The symbol is reconstructed by a re-match operation which places partial scanned data into memory and allows the data to be examined so that it is properly loaded whether data is acquired from scanning either the left or right side of the label first. Re-match allows labels having very small aspect ratios at extreme scanning angles to be readily captured.

Abstract: A bar code is formed of a number of parallel bars adapted to be provided circumferentially on a tubular or rod-like work and extend spirally about the center line of the work. In an alternative form, the bar code includes a number of parallel bars each adapted to extend continuously along the entire length of the work. In another alternative form, the bar code includes a number of parallel bars adapted to be provided on the surface of a belt-like work and each adapted to extend continuously along the entire length of the work.

Abstract: A bar code reader for an article (17) which is moved at least substantially in one direction (26) has a scanner (12) which generates a scanning light beam (11) which scans a surface (18) of the article (17) linewise, a light receiving arrangement (13) which includes an electronic evaluation circuit (14) with which bar codes (16) applied to the surface of the article (17) and scanned by the light beam (11) can be recognized and which is arranged outside of the parth of movement (20) of the article (17) and directed towards the front surface (18) of the article (17) as seen in the direction of movement.

Abstract: A scanner for reading indicia having portions of differing light reflectivity has means for directing a light beam from the scanner towards the indicia and collecting reflected light returning from the indicia. The scanner includes a scanning arrangement with a scanner component, such as a mirror. First and second vibratory means support the scanner component for angular oscillatory movement to scan the light beam in first and second orthogonal scan directions. The scanning arrangement includes read-start means for moving the scanner component to simultaneously scan the light beam in the first and second scan directions.

Abstract: To simplify a data reading apparatus for two-dimensional code data, a line sensor detection unit (30) for reading two-dimensional data includes an optical fiber band cable (3) bundling multiple optical fibers (31) of specified diameter in a band, and an upper end of the fibers is connected to a line sensor element (2) unit incorporated in the reading apparatus (S), and a lower end of the fibers is disposed opposite to an opening (11) of a specified size in the region of one or more two-dimensional code data in the bottom of the reading apparatus (S). The line sensor detection unit (3) including the optical fiber band cable (3) is disposed reciprocally parallel along the surface to be detected in an orthogonal direction, and the line sensor detection unit (30) is set movable within the range of the opening (11). A detection unit moving device (4) is disposed so as to read the two-dimensional code data.

Abstract: A symbol scanning system which adaptively changes scanning system parameters including light beam pattern and focus to improve barcode readability. The scanning system including; a scanner, responsive to coordinate control signals, for directing a light beam in a pattern at a symbol at a predetermined location, detecting a reflected portion of the light beam, and generating a feedback signal corresponding to the detected portion of the reflected light beam, a microprocessor, responsive to the feedback signal, for generating pattern control signals, and a pattern generator for generating the coordinate control signals in responsive to the pattern control signals and for determining the light beam pattern.

Abstract: A scan head is adjustably mounted in a ball-and, socket joint on a scan module or housing of an electro-optical system for reading coded indicia. The scan head is movable about three mutually orthogonal axes intersecting within the scan head, thereby steering a light beam emitted from the head and/or steering a field of view of a sensor.

Abstract: A hand-held symbology reader having a handle for grasping by a user and a head attached to the handle for adjustable angular movement of the head relative to the handle between the plurality of angular orientations. The head is selectively retained in a selected one of a plurality of angular orientations. The head is rotatable about three axes of rotation relative to the handle. The reader head has a rectangular pixel array that defines a rectangular imaging area, with the pixel array having a first position with a horizontal dimension of the pixel array that is greater than the vertical dimension of the pixel array, and a second position with the horizontal dimension that is less than the vertical dimension of the pixel array. The reader head is moveable such that the pixel array can be rotated between the first and second positions by rotating the reader head relative to the handle while the handle remains in a fixed position.

Abstract: A scanning arrangement in a scanner incorporating a scan element which is capable of the repetitive high-speed scanning of indicia having parts of different light reflectivity; for example, such as barcode symbols, and more particularly, pertains to the operation of a scanning arrangement of the type which, at high scanning speeds, will enable the scanning of indicia in variable and specified omni-directional scanning patterns. The variable omni-directional scanning pattern is attained through control over the electrical energy input to a read-start device for activating the scan element of the scanner for vibratory motion between first and second pairs of scan end position, in which the energy input is controlled and varied, and the scan element is rotated, in a manner so as to enable the scan element to implement the aforementioned omni-directional scanning patterns over the indicia.

Abstract: The present invention discloses a hand-held terminal adapted for data gathering, data processing, and voice and data communication. Included is a housing which includes a front section having an exterior and an interior, and a rear section having an exterior and an interior, wherein the front section is hinged to the rear section. These front and rear sections may be disposed in either a linear, angular, or parallel relationship. Key means for entering information into the terminal and display means for displaying information are incorporated into the exterior of the front section. A low power frequency hopping transceiver is disposed at least partially within the housing for receiving and transmitting information via the terminal. Also included are scanning means disposed within the housing for optically reading information stored in coded information sets and battery means disposed within the housing for providing electrical power.

Abstract: A portable optical scanner has a hand-held housing containing an optical sensor, a first memory for storing information representative of the output of the optical sensor, and a fiber optic image guide extending from the lower end of the housing to a position proximate the optical sensor for communicating an image being scanned from a scanned surface to the optical sensor. A lens disposed intermediate the optical sensor and image guide focuses the image upon the optical sensor. The fiber optic image guide has a lower surface formed at an angle of approximately 65 degrees to the longitudinal axis thereof such that the portable optical scanner is held at a conveniently comfortable angle during the scanning process to mitigate fatigue and improve the reliability of the scanning process. A microphone and second memory for storing information representative of the output of the microphone facilitates the recording of voice annotations to the image being scanned.

Abstract: An optical information reading method and device which prevents the generation of erroneous reading by specifying a reliable reading range for a bar code or like information. A microcomputer calculates the distance between the position of reflection of laser light from the bar code and a position at which the same laser light enters the scanning unit based on a time difference between the emission of the laser light and the reception of the reflected laser light. The microcomputer determines, through the calculation process, that the bar code is present within the suitable reading range only when the calculated distance is determined to be within the set reading range, and permits the scanning of the bar code.

Abstract: A method is disclosed for the reading graphical indicia that are encoded in accordance with a multidimensional symbology. The indicia are repeatedly scanning a signal representative of a pattern thereof until sufficient information is recognized to assure a valid reading operation. The signal, or a memorized representation thereof is decoded to obtain character information from code words of the indicia. A first value is assigned to each newly recognized character, and a second value is assigned to each character that was recognized in a preceding scan of the indicia. The first and second values are respectively cumulated into first and second sums. A function of the first sum and the second sum is computed, an audible click produced whenever a predetermined value of the function has been attained. The first and second sums are then reset. The rate of clicks informs the user of the progression of the reading operation.

Abstract: A bar-code reader includes a selection circuit which selects one of two operating modes of reading a bar code label by using the whole section or partial section of an image sensor.

Abstract: A scanner for reading two-dimensional optical information sets is described which includes a housing for supporting a photosensitive array associated with an optical string adapted to focus optical information on the array. Also provided are array and optical string controls for controlling the array and optical string such that the output of selected images on the array are processed via pattern recognition means. Images recognized to contain decodable optical information are displayed and highlighted by a display. In this fashion a user is assisted in aiming, recognizing, confirming the decodability, and decoding images of optical information incident on the array.

Abstract: A scanning arrangement in a scanner which is operative for repetitively scanning indicia having parts of different light reflectivity; for example, such as bar code symbol, and also pertains to the operation of a scanning arrangement of that type at high scanning speeds in two-dimensional or multi-axes scan patterns. A resonance asymmetric scan element (RASE) in which a scan element, which is preferably constituted of a mirror, is in effect attached along the upper side edges thereof to oscillation-imparting spring-means and not at the center of mass of the mirror as heretofore. This allows for higher frequencies of operation for the scan element at lower encountered stresses in that the fast axis of rotation of the scan element or mirror; in essence, the axis of oscillatory rotation about which the mirror is rotated at high frequencies substantially coincides with its center of mass.

Abstract: To reduce the size and weight of an optical scanner, the present invention provides a mirrorless beam scanning unit wherein the light emitter itself moves back and forth. In the preferred embodiments the light emitter is a visible light diode (VLD) mounted on the axis of a rotatable shaft. The VLD emits light in a direction perpendicular to the axis of the shaft. A lever arm attached to the shaft and an induction motor for moving the arm repeatedly rotate the shaft back and forth through a small rotational arc. The mirrorless scanner is mounted on a finger sized ring. This allows a user to wear the miniature optical scanner on a finger. A separate unit houses the other components of the scanning system, such as the analog signal processing circuitry, digitizer, decoder and any necessary interface to a data processing system. The separate unit can be worn on the user's belt or in a pocket, and a cable connects the separate unit to the ring mounted scanner.

Abstract: In a bar code reader, a field of view which includes a symbol to be read is imaged upon a light-responsive array such as a CCD imager device. The output of this array is transferred to a memory array to provide a bit-mapped type of binary representation of the image including the symbol. The memory is scanned (instead of the field of view itself being mechanically scanned) to recognize and decode the symbol. Because the angular orientation of the symbol is variable, this binary representation may be interpreted to determine how the memory array is to be scanned to recognize the bar code symbol. For example, the distinctive patterns of characters used in bar codes may be found by scanning the memory and the relative positions of these patterns interpreted to determine the position, size and shape of the symbol in the memory, thereby defining at what angular displacement the memory array need be addressed to traverse the rows of the bar code symbol.

Abstract: Sorting apparatus for flat, stackable articles, such as CDs, micro-cassettes, video tapes or similar articles. A single article is continuously removed from a stacked stock at the bottom side of the stack, and is then coded and moved forward by pushing members of a conveyor along an horizontal path, which is inclined transverse to the direction of travel. A series of discharge stations are positioned at the lower side of said path. The code applied ensures that each article is discharged at the correct station. Characterizing features of the apparatus are:1) the slanting position of both the stock, the path of travel and the conveyor;2) the adjustable bottom construction of the stock holder in conjunction with the pushing members of the conveyor.3) the transparent first portion of the path along which the objects are moved by the conveyor with scanning means and additional printers for stickers to be applied upon the passing articles.

Abstract: A bar code reader decodes a bar code symbol in a pixel image by transforming the data corresponding to the symbol along a first scan line, where the transformation comprises rotation and stretching. The reader generates a composite vector and a count vector from the transformed data. The reader then transforms (by rotating and stretching) another set of data corresponding to the symbol along a second scan line. The reader updates the composite and count vectors using the second set of transformed data. The reader then generates a one-dimensional composite signal from the composite and count vectors. The reader decodes the symbol by decoding the composite signal.

Abstract: A micro-bar code data processing system is capable of reducing the number of digits to be expressed by the micro-bar code by compressing information to be contained therein. The micro-bar code data processing system includes a receiver for receiving an original data to be contained in a micro-bar code; a reducer for reducing the number of digits of the original data by compressing the received original data; a converter for converting the compressed data into an encoded micro-bar code data; an outputter for outputting the encoded micro-bar code data; a receiver for receiving encoded data contained in the micro-bar code; a converter for converting the received encoded data into a compressed data; a restorer for restoring the original data from the compressed data by decompression of the compressed data, and an outputter for outputting the restored original data.

Abstract: A compact beam scanning information readout device and method for reading bar code or other information requires little or no orientation of the information to be scanned by virtue of its raster or omni directional scan capabilities. Only a single mirror is needed to generate two dimensional scans. A wide range of scan speeds are also possible for simple or complex one or two dimensional patterns. Scanning in two dimensions may be done with independent and continuous control of the scan in each dimension. The scan patterns may be electronically controlled to instantly achieve various orientations ranging from a straight line rotated about a point to continuously rotating complex patterns. A light collector, light detector, processor, and means of signal transmission are also included. In one embodiment the device is packaged in a housing resembling a wand or a thin flashlight and in another embodiment the device is packaged in a ceiling mountable housing which will not interfere with counter top work space.

Abstract: A stop sensing section senses movements by comparing data on two lines separated by a time interval in the same place (line) of the digital image information on the bar codes from a signal processing section and, when there is no movement, outputs a decode start trigger signal to a decoder section. A CPU in the decoder section, receiving the decode start trigger signal, judges that the bar codes have stopped in the proper position, and reads the bar code image information stored in a frame memory at that time for decoding.

Abstract: A management system automatically manages order and sales operations by facsimile communication between an orderer and a supplier. The management method of this system comprises checking the steps of the kind and number of commodities written on an order sheet which is sent from the orderer by facsimile, checking the stock of such commodities, sending an order content check request sheet to the orderer by facsimile in order to have the orderer check the contents of the order, collecting the ordered commodities based on an order content confirmation sheet sent from the orderer by facsimile, managing the remaining stock of the commodities, and performing accounting operations for the ordered commodities.

Abstract: A bar code conversion system and method identifies good data in the scan data array and analyzes that data to generate machine-interpretable code. A vision system optically scans bar code labels and places the resulting digital camera data into a two dimensional line scan data array of pixels. A process.sub.-- line function then searches the scan data array for three lines that intersect the initial bars and spaces of the bar code (called starting lines) and 3 lines that intersect the last bars and spaces (called ending lines). For each pair of starting and ending lines, a build.sub.-- composite generates a composite line using pixels in positions between the first pixel of a starting line and the last pixel of a corresponding ending line. A run.sub.-- length decode function is then invoked on each composite line to create a run length array of width values, each of which indicates the width (in pixels) of a bar or space of the bar code. Using statistical analysis, a convert.sub.-- bars.sub.-- and.sub.

Abstract: A method of recording a large quantity of data by one code mark. Four bit indicating fields (2a, 2b, 2c, 2d) for denoting a binary number of four bits are provided on the surface of a card (1). One numerical value is recorded by indicating predetermined bit parts of the four bit indicating fields (2a-2d) with the same color, and plural kinds of colors are mixedly given to the four bit indicating fields (2a-2d).

Abstract: A bar code reader decodes a bar code symbol, one character at a time, by analyzing the spaces of each character independently from the bars of each character. The reader determines the widths of each space and each bar. The reader then determines a space-width threshold based on the widths of the spaces and a bar-width threshold based on the widths of the bars. The reader then classifies each space as being either narrow or wide by comparing each space to the space-width threshold. The reader also classifies each bar as being either narrow or wide by comparing each bar to the bar-width threshold. The reader then decodes the character according to the narrow/wide classifications.

Abstract: A method which provides for handling misplaced transaction documents in an image based transaction processing system which performs transaction balancing. A preferred form of the method provides for displaying out-of-balance transactions such that transaction debit and credit data are displayed along with one or more document images. Using this transaction display, it is determined whether a transaction includes a misplaced document which does not belong, or whether a document is missing from the transaction. If a transaction is found to include a document which does not belong, data corresponding to the document is stored in a free item store. If a transaction is found to have a missing document, the free item store is accessed and one or more documents therefrom are displayed to permit determining whether any of these candidates correspond to the missing document.

Abstract: The imaging result obtained by an imaging device for imaging light reflected by a bar code symbol and incident on it via a first mirror is decoded by a decoder and stored in a first symbol label memory. The bar code symbol label is again imaged by the imaging device via a second mirror, and the imaging result is decoded and stored in a second symbol label memory. A comparator compares the contents of the two symbol label memories and synthesizes them in accordance with the comparison result. The result of synthesis is stored in the first symbol label memory.

Abstract: An automatic facsimile-receiving-sheet recognizing apparatus including: a device for automatically receiving facsimile information transmitted from an orderer; a device for detecting the position of a bar code, a mark sheet and a figure in a received sheet and automatically cutting their images; and a device for automatically recognizing the cut bar code, the mark sheet and the figure and transmitting the result of the recognition to a store controller of an automatic order receiving and sales control system.

Abstract: Two resonant cantilever beams oscillate in a sinusoidal pattern. Mirrors disposed on the oscillating ends of the cantilever beams are used to multiplex two scanning and collecting light beams. The cantilever beam parameters and mirror configuration are selected so that the scanning light beam is on the first mirror during the linear portion of its scan. As the first cantilever beam oscillates out of the linear portion of the sine wave, the deflection of the first mirror is just great enough to allow the scanning beam to strike the second mirror during the linear portion of the second mirror's scan. The process is repeated twice each cycle. The collection lens is large enough to receive the full aperture of both mirrors at all times. Multiplexing of scanning diodes is also accomplished by a controller circuit which alternately enables diodes disposed on the ends of respective first and second cantilever beams during the linear portion of each sine wave oscillation.

Abstract: The present invention discloses a hand-held terminal adapted for data gathering, data processing, and voice and data communication. Included is a housing which includes a front section having an exterior and an interior, and a rear section having an exterior and an interior, wherein the front section is hinged to the rear section. These front and rear sections may be disposed in either a linear, angular, or parallel relationship. Key means for entering information into the terminal and display means for displaying information are incorporated into the exterior of the front section. A low power frequency hopping transceiver is disposed at least partially within the housing for receiving and transmitting information via the terminal. Also included are scanning means disposed within the housing for optically reading information stored in coded information sets and battery means disposed within the housing for providing electrical power.

Abstract: The present invention provides methods and means for encoding digital data in the angular orientation of circularly asymmetric halftone dot patterns that are written into the halftone cells of digital halftone images. In keeping with standard practices, the sizes of these halftone dot patterns are modulated in accordance with the grayscale data sample values that are provided to define the image, so the average reflectance or transmittance of each of the halftone cells is modulated to provide a more or less standard halftone rendering of the image. In accordance with this invention, however, provision is made for modulating the angular orientation of the halftone dot patterns in accordance with digital data values, thereby embedding the digital data in the halftone image.

Abstract: A portable, hand-held data terminal of modular structure includes a base module with a keyboard and a display screen. A data collection and communications module includes a stacked arrangement of a communications interface main circuit board, a radio and a laser scanner assembly which are housed in a housing shell which is attachable to the base module. The radio is mounted in spaced relationship to one side of the main circuit board, while the laser scanner assembly is mounted to the other side of the main circuit board. A support frame and a plurality of ground planes in the sandwiched main circuit board and a routing circuit board form an RF cage for shielding RF interference which may be generated by the radio.

Abstract: In a method of distributing packages according to addresses, headings or the like applied to their surfaces by means of a separating and conveying device, it is provided that along a conveying path all surface portions of each previously separated package are scanned optically, for each package images are obtained from the surface portions of the package and, for further evaluation, the images are displayed simultaneously or approximately simultaneously. For each package, one or a plurality of the images are selected, and each selected image is assigned a sorting information for the distribution of the package corresponding to that image.

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: A goods scanning device in which the goods scanning window fitted in a housing is arranged upright beside the goods conveying surface has already been proposed. Furthermore, goods scanning devices in which the goods scanning window is arranged in the goods conveying surface and level with or above the latter are known from practice. In the case of the novel goods scanning device, the goods scanning performed by the goods scanning window is to be facilitated.For this purpose, the housing (12) is adjustable in such a way that the goods scanning window (13) is located as desired in a horizontal or vertical position (B, C, D). In a preferred embodiment, the goods scanning window (13) is arranged in the horizontal position (B, D) as desired in the region of the goods conveying surface (11) and level with the latter or above the goods conveying surface (11) and at a distance therefrom.The goods scanning device is particularly suitable for registering heavy and/or bulky articles.

Abstract: After a two-dimensional bar code is scanned to provide a stored image, the location (i.e., bounds, including orientation) of the bar code image within the scanned area image must be determined to enable decoding. Methods for locating the bar code image include the steps of sampling the stored image, identifying sampling traversals of bar code start and stop patterns, and correlating the identified start and stop pattern traversals to a common bar code image. The correlating data is then used to identify a nominally rectangular area bounding the bar code image. A bounding box may be identified as the smallest area capable of encompassing all of the start and stop pattern traversals related to a common bar code image. Output location data may specify the coordinates of the four corners of a bounding box for use in subsequent decoding. Related systems are described.

Abstract: A device for reading a bar code applied to a semiconductor wafer includes a laser source producing a coherent diverging light beam along a first optical path. An optical transmit/receive (T/R) unit has a first focal point on the first optical path upstream of the optical T/R unit for producing collimated light downstream thereof. The coherent diverging light beam is focussed into the first focal point of the optical T/R unit so that a parallel light beam having a planar wavefront is created downstream of the optical T/R unit for scanning the bar code. A beam divider mirror is disposed optically between the optical T/R unit and the first focal point for allowing the light beam from the laser source to pass through the T/R unit and for allowing light reflected from the semiconductor surface through the T/R unit to pass into a second focal point of the T/R unit on a second optical path and on to an image plane of the T/R unit on the second optical path for imaging the bar code.

Abstract: A reflection-transparence scanner comprises a reflection type scanner and a scanner converter which converts reflection type scanner as transparence type scanner, the scanner converter comprises: a casing, having a flat upper surface equipped with a scanning window; a light source, fixed to the casing; a power supply, to provide the electricity to the light source; and a light transmitter, fixed to the scanning window of the casing, and used to evenly distribute over a plane the light emitted by the light source.

Abstract: A scan pattern generator for use in a bar code reader which uses a single drive (one coil and one magnet) to produce movement of a reflective surface so as to produce an oscillating movement of the surface in two directions, thereby forming a raster-type scanning pattern when a light beam is reflected off the surface.

Abstract: A bar code label is read by automatically initiated scanning of the bar code symbol by a beam of light, as from a laser in a bar code scanner. Initially, the scanner is operated in a pulsed mode with low duty cycle (5%) pulses. These pulses are reflected from a reflective tape on one side of a detection zone or from an object carrying the label in the beam path. Then (because the beam is not scanning across the code) the reflected pulses (which are detected much like the bars and spaces of the code) are not detected. The ratio of the number of generated pulses to the reflected pulses is computed for a succession of pulses (ten pulses for example). If this ratio exceeds two (i.e., that the number of effective bars is less than the number of generated pulses during the succession), then the presence of the object is detected and the system, implemented in an application program in the microprocessor controller of the bar code scanner, initiates scanning of the bar code.

Abstract: A bar code scanner employs an electronic means for causing the light beam to scan a bar code symbol, rather than using a mechanical device to generate the scan. A linear array of light sources, activated one at a time in a regular sequence, may be imaged upon the bar code symbol to simulate a scanned beam. Instead of a single linear array of light sources, a multiple-line array may be employed, producing multiple scan lines. The multiple scan lines may be activated in sequence, or activated simultaneously (time-division or frequency-division multiplexed. The multiple scan lines can provide signal enhancement, noise reduction or fault correction if directed to the same bar code pattern. Multiple scan lines may be generated using a single light source and a beam splitter, with mechanical scanning, as well as by the sequentially-activated light suorces. Multiple simultaneous scan lines may be employed to generate a raster scan at lower mechanical scan frequency.

Abstract: A reflective deflector of a light beam which scans in opposite directions across a bar code is controlled in scan angle by monitoring the AC component of a current passing through a winding of a scanning motor which oscillates the deflector to scan the beam across the code over a scan angle. The inductance of the winding corresponds to the length of the scan angle and is measured in terms of the peak to peak value of the AC component during a scan period or frame which occurs over an interval corresponding to the reciprocal of the scan rate. During successive periods, successive trains of pulses are generated. The number of pulses or their duty cycle during each period is changed in accordance with an error signal corresponding to the difference between the desired scan angle and the peak to peak value of the AC component.

Abstract: An optical scanning wand is disclosed that provides improved illumination of the document scanned and improved visual control of the movement of the wand. The wand comprises a handle having a hollow tip disposed at an oblique angle thereto. The tip has a scanning window opening at its distal end that defines the target zone through which the image being scanned should pass. In one embodiment light is directed to the document through the transparent tip. In another embodiment the light is directed toward the document by optical fibers from a light source located behind the wand's light sensor and the tip is cut away to provide viewing window openings.

Abstract: In bar code symbol scanning systems employing laser, optical and sensor components, a mirrorless scanner arrangement mounts one or more of these components on a drive for repetitive reciprocating movement either about an axis or in a plane to effect scanning.