Abstract: A portable laser diode scanning head, aimable at each symbol to be read, emits and receives non-readily-visible laser light, and is equipped with a trigger-actuated aiming light arrangement for visually locating and tracking each symbol. A compact laser diode optical train and an optical folded path assembly, as well as an interchangeable component design and an integral window construction for the head also are disclosed.

Abstract: A method for combining decoded scan fragments of a bar code symbol composed of a delimited plurality of bar code elements representing an ordered sequence of data characters. The method includes scanning the symbol along a first scan path that includes a delimiter to obtain a first sequence of data characters; scanning the symbol along a second scan path that includes another delimiter to obtain a second sequence of data characters; comparing the predetermined length to the lengths of the first and second sequences of data characters; and based on the comparison combining the first and second sequences to produce the ordered sequence of data characters.

Abstract: A method of entering a hand-marked response into a system by altering a predetermined modified bar code symbol in a manner so that the bar code is rendered readable. In this manner, bar code reading devices can be utilized to detect the hand marked response. In an alternative embodiment, one of several potential responses may be marked and rendered non-decodable. A bar code reading device determines which of the several responses has been hand-marked by ascertaining which is non-decodable. Marking the response sheets may be aided by using an opaque template sheet or using a pressure sensitive overlay sheet.

Abstract: A multi-bit digitizer for a bar code reader for detecting and reading bar code symbols, which are generally printed on a label or on the surface of an article. The multi-bit digitizer detects the presence of edges of a scanned bar code symbol, and also measures the strength of each detected edge therein. During a scanning operation, a sensor senses light reflected from a bar code symbol and produces an analog scan signal representative thereof. Positive and negative edges in the analog scan signal are detected, and timing signals are developed representative thereof. The strength of each detected edge in the analog scan signal is determined by measuring the pulse-widths of the timing signals. A separate edge-direction signal is also developed which indicates the nature of the edge.

Abstract: An optical scanning method for reading indicia of a type having regions of different light reflectivity, the method comprising the steps of providing a scanning unit having a field of view in which indicia may be read; providing an object sensor directed at a location within or nearby the field of view of the scanning unit; supporting the scanning unit and object sensor on a movable structure; moving the scanning unit and object sensor in unison with the structure; and electrically connecting the object sensor and scanning unit, including the steps of differentiating an output of the object sensor to provide an electrical signal representative of the degree of change in the amount of reflected light, and activating the scanning unit when there is more than a predetermined change in the differentiated signal, whether that change is from an increase or decrease in the amount of reflected light; wherein when an object that is more or less reflective than the background enters the field of view the scanning unit

Abstract: A method of and arrangement for updating inventory markings include printing an updated label containing updated information such as price obtained from the data base of a host computer on a real-time basis, The updated label is applied to a product identified by a scanner,

Abstract: A system for digitizing an analog electric signal generated from a photoelectronic conversion of reflected light when scanning indicia having specifically-separated, light-reflective portions. The system detects zero-crossings of the second derivative signal, and ignores noise signals from a first derivative of the analog signal.

Abstract: Combining scan fragments of a bar code symbol. Each fragment is represented by a series of values, with each value representing the width of an element in the fragment. The alignment at which the fragments are combined is determined by shifting the alignment of the fragments over a range of positions, and determining for each position an index of the overall degree of similarity between the aligned values of the two fragments at that position. The fragments are combined at an alignment that produces a relatively larger index value (e.g., that maximizes the index). The index of overall similarity may be a correlation factor representing the degree of correlation, at each tested alignment, between the series of values representing each fragment. The index of overall similarity may alternately be the number of consecutive matching elements. At each position, the values in each series are compared and the number of consecutive values that match within a preselected tolerance is determined.

Abstract: A trigger-operated or triggerless scanner reads symbols with a first scan pattern in a first intended position of hand-held use. Either scanner may be mounted on a stand-alone fixture wherein the first scan pattern is converted to a second, different scan pattern, again for reading indicia in a second intended position of workstation use. Various signal processing digitizing circuits for faithful digital reconstruction of the symbols are disclosed.

Abstract: In order to improve security for holographic labels which are positioned on a substrate base, a bar code symbol with regions of different light reflective properties is holographically recorded on the base. The base may be, for example an information card, such as a credit card, a label, or a container for a product. The bar code symbol can be recorded so that it is visible to the eye in white light (e.g., as a rainbow hologram) or so that it requires an appropriate reference beam for reconstruction. A reading apparatus (e.g., a bar code reader) directs light at the holographic bar code symbol and detects the reflected optical information with a detector such as a CCD array. The reading apparatus can be a stand-alone device or, in the case of a credit card, can be incorporated into a conventional swiper for reading magnetic information on a strip on the card. A non-holographic bar code symbol can also be provided on or near a holographic display element, e.g., a rainbow hologram.

Abstract: The laser diode of an optical scanning system is located in a separate unit and light therefrom carried to a remote scan head via an optical fiber. This reduces the size and weight of the scan head and reduces the temperature sensitivity of the scan head. The scan head may include an optical sensor for detecting light reflected from scanned symbols. Alternatively, the separate unit may house the sensor, and the same fiber or an additional fiber will collect the reflected light and transmit that light back to the sensor. A portion of the optical fiber is attached to the optical scan unit such that the first end is free to vibrate within the optical scan unit in response to a mechanical force applied to the optical scan unit by a user, for example by shaking or striking the scan unit.

Abstract: A combined range laser scanner and method for electro-optically reading indicia such as bar codes having parts of different light reflectivity which utilizes two laser diode optical illumination systems optimally focused for different working ranges. A first laser illumination system is optimized for contact operation and has a range extending to approximately two feet. The second laser illumination system is optimized for longer range scanning from approximately two to seventeen feet, and the two laser scanning systems are integrated into one combined range laser scanner. The combined range laser scanner incorporates therein logic circuitry which enables either laser illumination system as required from the particular scanning application. Depending upon which laser illumination system is selected, the laser spot speed (e.g. amplitude of the drive signal for the scanning motor) is controlled to limit the frequency of received light signals to that of standard signal processing and decoding circuits.

Abstract: A packet data transmission system is disclosed in which remote units, such as remote hand-held data gathering units, which normally communicate with remote base stations via a spread spectrum RF communications, are initialized via spread spectrum RF communications. A network chipping sequence is provided for encoding normal communications and a universal chipping sequence is provided for encoding communications relating to initialization of the remote units. The network chipping sequence is adjustable and must be initialized in each of the remote units to enable normal communications. The universal chipping code is fixed for all remote devices and base stations. Since the universal chipping code is fixed, spread spectrum RF communications of the initialization data, using the universal chipping code, can be effected even if the network chipping sequence is not initially set in the remote units.

Abstract: A portable data input or computer system includes a keyboard, another data input device such as an optical scanner, a data processor module, and a display. All of those system components are configured for carrying and/or securing on a garment, such as a vest. Typically, the garment has a number of pockets. The operator can wear the garment and carry the system components in pockets when not using them. At such times, the system components are out of the way. The display may be flipped up so that, when the system is in use, displayed data is visible to the operator without removing the display from the pocket. The operator may activate the keyboard with only one hand while it is still in its pocket, or the operator can remove the keyboard from the pocket, hold it in one hand and key in data with the other hand. To input other data, for example by scanning bar code type indicia, the operator removes the scanner from its pocket, points the scanner at the bar code and triggers the scanner to read the indicia.

Abstract: An apparatus and method for reading data in the form of indicia on a surface of a target, the indicia having a preferred reading direction, including a light source for illuminating a portion of the surface to be read with a laser beam in a scanning pattern at a predetermined scanning angle so as to scan spatially adjacent portions of the surface. A detector and a processor is provided that is operative for detecting at least a portion of the light reflected from the indicia and storing representations thereof, and further determining the angular difference between the preferred reading direction and the scanning angle.

Abstract: A method for operating a point-of-transaction system carried by a fixture to efficiently use areas of a store during periods of differing intensity of usage, by placing the fixture at a prescribed area of the store and configuring the point-of-transaction system with point-of-transaction terminal components for processing items to be purchased by customers during a period of relatively intense usage. During a period of relatively less intense usage, the fixture is reconfigured as a display stand by relocating at least some of said point-of-transaction components from the fixture, and overlying remaining point-of-transaction components of the fixture with a display surface. During intense usage periods the components are located on a shelf overlying the fixture. The reconfiguration includes repositioning the shelf together with the remaining components to a location beneath the display surface within the fixture.