Abstract: A method for on-premise processing of articles such as food items bearing linear or two-dimensional bar code symbols comprises the steps of defining an on-premise storage unit such as a refrigerator or pantry for releasable storage of the articles, scanning and storing the bar codes of articles entering and withdrawn from the storage unit, scanning and storing the bar codes of articles returned to the storage unit following the withdrawal thereof from the storage unit and providing output indication of failure of correspondence of storage of stored bar codes in the steps of entry and withdrawal scanning and return scanning. A "shopping list" or inventory readout is obtainable from the failures of correspondence. Methods are provided also for processing two-dimensional bar codes symbols wherein messages encoded therein are selectively audibilized in connection with a refrigerator or pantry.

Abstract: An optical scanning system for scanning indicia having portions of differing light reflectivity has a light emitter assembly, with a single light source, for emitting a beam of light to scan across the indicia. A first optical detector receives light reflected back from a first portion of the indicia. A second optical detector receives light reflected back from a second portion of the indicia. Each of the optical detectors includes a photodetector, a lens and an aperture which is disposed between the photodetector and lens.

Abstract: A data processing system includes a head for electro-optically reading coded indicia to generate digital decoded data in a predetermined data exchange format. An interface arrangement is used for connecting the head to any selected one of a plurality of electronic devices having individual data processors. Thus, a common data exchange format is established for all the devices, and conversion circuitry is employed for converting the predetermined data exchange format to the common format. The conversion circuitry is operatively connected between the head and the selected device.

Abstract: A scanning device for reading indicia of differing light reflectivity, including bar code or matrix array symbols, has a single light emitter, such as a laser or light emitting diode, for generating a scanning light beam to visually illuminate sequential portions of the indicia. A sensor, such as a charge coupled or other solid state imaging device, simultaneously detects light reflected from portions of the indicia and generates an electrical signal representative of the spacial intensity variations the portions of the indicia. The scanning device may also include an ambient light sensor, and a second light emitter for use only in aiming or orienting the scanning device. A photodetector may also be provided to separately detect one symbol virtually simultaneous with the detection of another symbol by the sensor or to provide dual modalities. A method for reading indicia is also provided.

Abstract: A target bearing a coded indicium is found by a system for electro-optically reading indicia. Upon the determination that the indicium is located within a range of working distances relative to a hand-held housing, a user is prompted that the indicium is ready to be read. A sonic signal is transmitted by a ranger, and a return echo from the indicium is received. An auditory prompt, such as a single tone or a series of tones, advises the user that the indicium is within range.

Abstract: A packet data transmission system is used to link a number of remote hand-held data-gathering units such as bar code readers to a central computer. Data packets are sent from the remote units by an RF link to intermediate base stations, then sent by the base stations to the central computer by a serial link. Direct sequence spread spectrum modulation is used for the RF link. The remote hand-held units initiate an exchange using RF transmission to and from the base stations, receiving only during a rigid time window following a transmission from the remote unit. The base stations cannot initiate an exchange with the remote units, but instead send data to the remote units only as part of the exchange. To alert a remote unit when a message is waiting at a base station to be sent to a particular unit, some of the acknowledge (base-to-remote) packets sent by the base station may contain an identification such as a list of all remote units (identified by ID number) which have messages waiting.

Abstract: An oscillator is provided having a plurality of cascade coupled inverters Each one of the inverters is a differential amplifier having a p-input and an n-input. The output of each one of the amplifiers is connected to: the n-input of the next succeeding amplifier to provide a closed loop, or ring oscillator; and, the p-input of an amplifier positioned an even number of amplifier stages forward of such next succeeding amplifier. In a preferred embodiment, each amplifier in the ring includes an n channel transistor (nMOS transistor) connected in a totem pole arrangement, to a p channel transistor (pMOS transistor). The gate of the nMOS transistor provides the n-input and gate of the pMOS transistor provides the p-input. The source and drain paths of the pMOS and nMOS transistors are connected together to provide an output for the amplifier.

Abstract: A scanner module for directing a light beam to scan an optically encoded symbol includes a scanner component and a permanent magnet mounted for joint oscillatory motion on a support to scan the light beam by a flexible, resilient member having one end connected to the support, and an opposite end connected to a frame. This oscillatory motion is induced by the interacting magnetic fields established by the permanent magnet and an electromagnetic coil driven by an AC current. Bidirectional light beam scanning is achieved by an additional electromagnetic coil.

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 sources. Multiple simultaneous scan lines may be employed to generate a raster scan at lower mechanical scan frequency.

Abstract: An interface arrangement is connected between a scanning head for electro-optically reading bar code symbols and a host device having a host processor operative for processing signals with a predetermined data exchange format. The interface arrangement includes a housing; a first connector on the housing for direct connection to the host device; a second connector on the housing for direct connection to a head cable connected to the scanning head; and a conversion circuit within the housing for converting decoded signals generated in the head into data signals having a format compatible with the predetermined data exchange format of the host processor.

Abstract: To reduce the size and weight of an optical scanner, the present invention provides a mirrorless beam scanning unit. A flexible support structure, such as one or more strips of mylar, movably mounts the light emitter in response to a motive force, for example as might be applied by a combination of a permanent magnet coupled to the light emitter and a fixedly mounted electromagnet driven by an alternating current signal. Reciprocation of the light emitter during emission of light by the light emitter causes the light to scan a surface, such as a surface beating a bar code label.

Abstract: A portable terminal has a housing with a motion detector housed therein. Movement of the housing from a a rest position is detected by sensing the motion of a coil or magnet located within the housing. A controller activates circuitry within the housing responsive to the detected movement. The terminal may include a touch sensitive display, on a flat front surface of the housing. A light emitter and an optical detector may also be disposed within the housing. Preferably, the terminal also houses a sensor for sensing different specific positional orientations of the terminal and activating or deactivating terminal functions depending on the sensed orientation.

Abstract: An optical scanner includes a light source for producing a light beam for scanning a target wherein the light beam scans a target at a first low frequency and the beam also dithers in a direction orthogonal to the scanning direction at a second, high frequency. The dithering motion can be imparted by a oscillating mirror and allows improved reading of, for example, bar code symbols. In addition an optical scanner includes a laser light source producing a laser light beam into which a time-varying phase is introduced in order to reduce laser speckle noise.

Abstract: Inventory item records are affixed to inventory item holders. The inventory item records comprise two-dimensional bar code labels containing encoded item identification information and reordering information for ordering replacement inventory items. The replacement inventory items are labeled with two-dimensional bar-coded information describing the ultimate destination, and packed into a container for shipment to a receiving/distribution center. The destination information is scanned and decoded at the receiving/distribution center to enable proper routing of the replacement inventory items.

Abstract: An original document of one or more pages containing human-readable printed information is encoded in one or more two-dimensional bar code symbols and transmitted by facsimile to a remote site where a facsimile of the symbols is machine read, decoded and printed to provide an accurate reproduction of the original document. The facsimile symbol can be facsimile transmitted to another remote site where the facsimile symbol is regenerated, machine read, decoded and printed as another reproduction of the original document. The machine readability of the symbol facilitates computer entry of the original document printed information. The coded symbol may also contain data used at a remote site to control processing and dissemination of the original document printed information.

Abstract: A method and apparatus for bias suppression which includes a transmitter having a bias suppression encoder and a closed-loop VCO FM modulator and a receiver having a bias suppression decoder and an AC coupled FM demodulator. The bias suppression encoder generates a running sum of an encoded digital data signal as well as the sum of an (N+1)-bit block of an injected digital data signal such that the encoder may invert a block of (N+1)-bits of the injected data signal if both sums are of the same polarity thereby reducing the average DC bias of the encoded digital data signal. The encoded data signal is modulated using a closed-loop VCO FM modulator with the DC tracking effect minimized as compared to modulating the non-encoded signal directly.

Abstract: A reader for reading a bar code symbol consisting of badly printed bars on a clean background generates a signal having portions corresponding to the different light reflectivities of the bars and the spaces. Those portions of the signal corresponding to the bars will include high frequency noise components owing to the badly printed bars whereas portions of the signal corresponding to the spaces will be noise-free. The information encoded in the bar code symbol can thus be recovered by identifying the noisy and noise-free portions of the signal.

Abstract: An optical scanning module has a metal base, a first circuit board mounted across one end of the metal base and a second circuit board mounted orthogonal to the first circuit board. The metal base supports a light emitter for producing a scanning beam and serves as a heat sink for the emitter. A flexible support attached to the metal base supports a mirror for oscillating motion. The module includes a drive mechanism, typically in the form of a permanent magnet and electromagnet, for producing reciprocal motion of the mirror. A detector included in the module senses light reflected from an indicia scanned by the beam. A flexible electrical cable connects the circuitry on the first and second circuit boards so that circuitry operates together to produce all signals necessary for operation of the scanner module and to process the electrical signals from the detector. Preferred embodiments include a flexible support consisting of a planar spring located between the mirror and one of the magnets.