Abstract: A code reader configured with a plurality of types of illuminators is disclosed. Having access to the plurality of illuminator types, the code reader controls a reading attempt by first selecting and using one of the available illuminators. If the use of that illuminator fails to yield a valid read, the code reader selects a second of the available illuminators and reattempts the read. Again, upon failure to obtain a valid read, the coder reader selects yet another illuminator and so on until a valid read is obtained else all illuminator options have been exhausted. Illuminator selection order is set as a factory default, but adapts based on actual performance in a users environment. Alternately, illuminator order selection is based on range from the target. Such range may be proximity based, or based on marker beam distance calculations. Additionally, the illuminators are mounted on a single assembly along with read control program memory for ease in upgrade replacement.

Abstract: An optoelectronic system for reading reliefs, such as a mould number, on a transparent container. The optoelectronic system associates a light source and a reception system, the light source illuminating the entire periphery of part of the body of the container and the reception system being capable of reproducing a complete image of the periphery of that part of the body of the container.

Abstract: A hand scanner for scanning a document by being moved by hand and sending the resulting image data to a host is disclosed. The scanner is easily movable over a document without meandering. Because the scanner includes a minimum number of parts, it is small in size and simple in configuration.

Abstract: This invention relates to a technique of contrast measurement especially useful for the measurement of contrast of laser mark. The technique involves measuring the light intensity coming from a laser mark and the intensity coming from a background on the integrated circuit, calculating the contrast based on the intensities, and comparing to a gray scale. This invention enables contrast to be measured and communicated with respect to a set of references and hence eliminates subjective judgement.

Abstract: A method of arranging an item imager with a least two imaging site, each lit by a beam through a fibre-optic array, this method including: providing a beam-intensity-adjust array including a lens stage for focusing each beam on each fibre optic array such that a shift in lens-focus changes output light from the array.

Abstract: A hand-held scanning device is disclosed in which the scanning device housing window has a recessed optical portion of the window formed such that the recessed optical portion of the window does not come into contact with the object being scanned while a scan is being performed. This recessed optical portion of the window eliminates damage caused by contact with the object being scanned to the optical portion of the window. The recessed portion of the window is formed without corners in such a manner that it may easily be wiped clean by the end user without dirt, dust and the like building up in corners of the recess. The recessed portion of the window is also formed in such a manner as to maintain the object in a relatively flat position under the scan window throughout the scanning process.

Abstract: An information transducing system including a data tag for digitally storing data and a tag reader for selectively activating data tags such that a terminal may at least receive the digitally stored data in a selected data tag for storage and/or transmission of the digitally stored data in the data tag. The tag reader may be operated so as to transmit a unidirectional beam of radiant energy such that it impinges on a data tag to be read. The radiant energy radiating from the tag reader activates the data tag causing the data tag to transmit its digitally stored data via radiant energy to the tag reader and/or a terminal operably coupled to the tag reader.

Abstract: A scanner with an extended depth of focus for electro-optically reading indicia having parts of different light reflectivity, comprises a collection optical system for collecting radiation reflected from objects in the field of view along plural different optical axes and an optical detector for detecting radiation collected by the collection optical system along each of the plural different optical axes and for generating electrical output signals indicative thereof. The scanner further includes processing circuitry for processing the output signals of the optical detector by comparing the output signals of the optical detector with one another, a memory for storing the detector output signals and further processing circuitry receiving the stored output signals of the optical detector from the memory and selectively outputting one of the received signals to a decoder.

Abstract: A portable optical reader system for reading optical information over a substantial range of distances includes a casing having a light receiving opening for alignment with optical information. Further included is a reading sensor for converting a reflected light image of optical information into an information signal and reflected light optical elements for forming a reflected light image. The optical system is adjustable to tend to focus a reflected light image of optical information, located within a substantial range of distances, onto the reading sensor. A light beam generator is associated with the casing and directed relative to the optical elements and the light receiving opening such that a light beam generated thereby will impinge on an information carrier, having optical information to be read, and will be reflected therefrom through the light receiving opening and via the optical elements to the reading sensor.

Abstract: A bar code reader comprises: a laser for projecting light; a polygon mirror for scanning a bar code with light from the laser; a way-in window allowing the reflecting light from the bar code to pass therethrough; and a light receiving surface including a photo diode, for receiving the reflecting light through the way-in window and transforming the reflecting light into an electrical signal, wherein the light receiving surface is formed to take a rectangle corresponding to a shape and a size of the way-in window, the light receiving surface is placed apart from the way-in window, while facing the way-in window, and no condenser lens is provided between the light receiving surface and the way-in window.

Abstract: A method of and an apparatus for detecting information from a code marking formed on a carrier by illuminating the code marking with illuminating light and detecting an emission from an illuminated position on which the illuminating light is projected. The code marking is a two-dimensional code marking bearing the information in first and second directions perpendicular to each other, and an illuminated area at the illuminated position is of a fine ribbon-like shape having a length greater than a maximum possible width of the code marking in the first direction and smaller than a minimum possible information width in the second direction. Illumination of the code marking is carried out by moving in a direction parallel to the second direction while traversing in the first direction.

Abstract: An optical reader for reading indicia such as bar codes comprises a first and second light source for generating first and second light beams of mutually orthogonal polarization orientations, and a polarized beam splitter for combining the beams without the effects of parallax or vignetting. One of the light sources is a short range light source and the other is a long range light source. The reader may be a scanner or a field of view reader. In addition, an optical reader is provided capable of reading all 2D symbologies comprising a flying spot laser scanner arrangement and a field of view reader. The respective laser sources generate light at different wavelengths and a dichroic filter is provided to allow either system to be used without parallax effects. The laser scanner beam can be used to aim the reader when carrying out field of view reading.

Abstract: A bar-code optical scanner in which a converging prism is disposed in front of the light source to concentrate emitted light into a light beam, permitting it to be projected onto the bar code; the lens which is disposed between the reflector and the photosensor has a rectangular through hole forming a diaphragm, the long side of the through hole being disposed in parallel to the transversely disposed charge coupled device of the photosensor, the diameter of the through hole gradually reducing from the side of the photosensor toward the side of the reflector to match with the light path of reflected light passing therethrough; a converging meniscus lens is disposed in front of the photosensor to concentrate reflected light from the lens into the charge coupled device of the photosensor.

Abstract: An electro-optical scanning device reads indicia having parts of different light reflectivity, including bar codes and matrix arrays such as UPSCODES. The scanning device includes laser or light emitting diodes for emitting at least two light beams of the same or different wavelengths. The light beams may be visible to the human eye, and the beams are optically directed to form one or two scan lines to scan portions of a symbol. Dual photosensor(s) or a charge coupled device detects light reflected from the different portions of the symbol. The charge coupled device can be used to detect either reflected ambient light or the reflected visible light from the beams emitted by the diodes. The photosensors generate signals corresponding to the detected light which can be processed simultaneously. The device is particularly useful in reading two dimensional or more complex symbols. Methods for reading indicia are also described.

Abstract: An intensity compensated scanning system includes laser means for providing a laser beam; scanner means for sweeping the laser beam in an arcuate path across a surface to be scanned; means for sensing the return laser beam reflected from the surface to be scanned; means for quantifying the decrease in the intensity of the return laser beam at the scan extremity portion relative to the intermediate scan portion; and means responsive to the means for quantifying for varying the power to the laser means at the scan extremity portion relative to that at the intermediate scan portion for balancing the intensity of the return laser beam reflected from the surface to the means for sensing.

Abstract: A lamp projecting a high-intensity optical beam of spectral radiation, with an IR-extracting (cooling) array including an IR-dissipating "black-box" arranged to receive IR and convert it to box-heat, plus an IR-diverting "hot-mirror" interposed along the beam to divert (only) the IR to this "black-box".

Abstract: A self-monitored optical sensor having a code plate having a plurality of tracks disposed thereon. Each of the tracks comprises a pattern of reflective and absorptive segments that form a code that is indicative of a discrete position of the code plate. The code plate further includes a monitoring track that encodes a number of expected absorptive or reflective segments in the code plate at each discrete position. A detector circuit compares the number of absorptive or reflective segments detected and the number of expected absorptive or reflective segments in order to determine if there is a fault in the code plate.

Abstract: The invention relates to a method for the detection of imprint markings (6) made into an object, especially for reading a bar code, the markings (6, 6a) of which are formed into a second level (8) which differs from the surface level (4) of the object, the second level (8) being arranged to reflect a radiation (5) to at least some extent. The method utilizes apparatus which transmit (1) and receive (2) a radiation, the apparatus being separated from each other by a separating wall (3) which is arranged transversely with respect to the surface plane of the object and near the surface (4), the wall preventing radiation from passing from the transmitting (1) to the receiving apparatus (2) at such locations where the surface (4), which is at a higher lever, extends to an edge (7) of the separating wall (3).

Abstract: A symbology reader having a pair of optical sources for producing cursor beams. The cursor beams are emitted from two spaced apart locations on the reader and angled with respect to an image direction of a detector assembly within the reader. The cursor beams intersect at a desired object distance to form a composite image indicating that the reader is positioned an appropriate distance from a target object. In one embodiment, multiple composite images are formed. The composite images are spaced apart to delineate the extent of an object field of the detector assembly. In one embodiment, the optical sources are LEDs concealed beneath a mounting platform and emitting light transversely to the image direction. In this embodiment, turning mirrors redirect the light forward of the reader to form the cursor beams.

Abstract: The present invention relates to a method and an apparatus for enhancing the optical image of information-containing symbols captured off reflective surfaces/using a conventional optical scanning camera. The method involves positioning the imaging assembly of the camera atop an information-containing coded symbol located on a component surface, where the imaging assembly includes a diffuser element and LED lighting array for illuminating the symbol, illuminating the surface and the symbol, and moving the diffuser element to a location between the coded symbol and the camera lens such that only light returning directly from the symbol is able to pass through the voided region of the diffuser element, before imaging the coded element.

Abstract: A data symbol reader which reads a two-dimensional data symbol includes a reading device which receives light reflected from the data symbol, a casing in which the reading device is provided, and a guide member which defines a symbol reading area in which the data symbol can be positioned. The guide member is attached to the casing and is moveable between a fisrt postion in witch the position of the data symbol realative to the symbol reading area can be viewed from the exterior of the data symbol reader, and a second position in whitch the data symbol can be read by the the reading device in the casing.

Abstract: A laser beam scanning apparatus including a device for scanning a laser beam, and a device for changing the scanning direction of the laser beam into a plurality of different scanning directions in one of which the laser beam is attenuated in comparison to a laser beam traveling in another scanning direction. A scanning optical path detecting device detects whether or not the laser beam is being scanned in the scanning direction in which it is attenuated. The laser beam scanning apparatus further includes a device for detecting a laser beam reflected from a bar code scanned by a laser beam emanating from the scanning direction changing device, and a device for controlling the intensity of the laser beam incident on the laser beam detecting device in response to the result of detection made by the scanning optical path detecting device.

Abstract: A symbology reader which reduces the effects of specular reflection. A plurality of illumination sources emit light toward a target object. A first polarization filter receives the unpolarized light from the illumination sources and transmits only light polarized in a first direction. Light reflected from the target object travels back to the reader where it is received by a second polarizer which is oriented to block light polarized in the first direction and transmit only light polarized in a second direction orthogonal to the first polarization direction. Non-specularly reflected light reflected from the target object is largely transmitted by the second polarizer to a detector assembly within the symbology reader. In one embodiment the polarization filters are part of a window which covers an output aperture of the reader. The polarization filters are implemented as discrete pieces of laminar polarizing film attached to a transparent window base.

Abstract: A lamp projecting a high-intensity optical beam of spectral radiation, with an IR-extracting (cooling) array including an IR-dissipating "black-box" arranged to receive IR and convert it to box-heat, plus an IR-diverting "hot-mirror" interposed along the beam to divert (only) the IR to this "black-box".

Abstract: A solid-state scanner for reading bar codes or projecting images is described. The scanner operates either in a reading mode or a calibrate mode using the same hardware. Use of two-dimensional array light sources minimizes the size of the semiconductor chips containing the light source arrays is provided. Use of oversampling or anamorphic optical systems increase tolerances to angular misorientations is also discussed. Used in conjunction with a mechanical scanning device, the scanner is capable of reading two-dimensional bar codes or generating two-dimensional images.

Abstract: A wiring base for a bar code scanner or the like provides a conductive housing open at one face for connecting cables at various screw terminals to a circuit board providing signal processing for the signals and permitting various different-connections of the cables. The shields of the cables pass into the conductive housing to be terminated on conductive housing thereby enlisting the conductive housing as a shield around all the cables. Attachment of the scanning head to the upper face of the wiring base closes the housing to be free from the egress of dust or liquid and completes a Faraday cage around the connections while connecting two multi-pin connectors one within the base and one within the scanner, communicating the signals to the scanner. A visual indicator attached within the conductive housing indicates the presence of power and its polarity prior to connection of the scanning head to the conductive housing.

Abstract: An optical memory diffraction grating having a plurality of spaced ridges each having a plurality of optically reflective facets. When illuminated with an incident light beam the grating produces a number of diffracted beams corresponding to the number of facets. The diffracted beams can be machine read by a reading device which produces a reading light beam directed at the grating. The reading device has a plurality of detectors positioned to be illuminated by the diffracted light beams. Information can be stored in the optical memory by locally changing the optical properties of the grating. The grating may be employed in security cards and documents. The grating may be arranged as a bar code or as a pixelgram. Reading, writing and erasing devices are also claimed.

Abstract: Scan units scan top surfaces of articles A and B with a laser beam as they are transported by a conveyor belt. The scan units are capable of changing the focal position of the laser beam within a predetermined range. Changing the focal position of the laser beam requires a predetermined response time. The heights of articles A and B are detected by a height detection unit in an amount of time equal to or less than the response time before they are scanned by the laser beam. When the heights of the articles as detected by the height detection unit change, a control unit will change at predetermined time intervals the focal position of the laser beam that is generated by each of the scan units. This allows the top surfaces of articles A and B, which are transported at short time intervals, to be scanned efficiently with the focused laser beam, permitting the efficient reading of bar codes and any other symbols that are formed on the top surfaces of articles A and B.

Abstract: A paper attribute detector for use in combination with a strip chart recorder includes a paper web having a plurality of connected pages. Each of the pages has electronically scannable indicia preferably on an unrecorded side of the paper. In the preferred embodiment, the indicia are realized in bar code form and are used to encode various attributes such as page number, paper quality, paper sensitivity, and so on. Indicia scanning means are provided for detecting the page indicia as the paper web travels through the recorder. In the preferred embodiment, the scanning means includes one or more electro-optical sensors. The indicia may be aligned parallel to or transverse the travel direction of the web.

Abstract: An apparatus and method is presented wherein the lens system or assembly is fixed in its location along an optical axis between an object and its image. The focusing of the object, which may vary its position along the optical axis, occurs through adjusting a detection medium or an imager to the position in image space where the image space is focused on its image plane. The invention is structured to facilitate this focusing in an automatic and very rapid manner to accommodate rapid changes in the location of the object along the optical axis.

Abstract: Each identification mark consisting of hologram or diffraction grating having a unique diffractive property which can be detected with optical identification means is formed on a seal, and, by affixing such seals as a combination and reading them, the analysis or forgery of each identification mark is made highly difficult. Since the possible modes of combination and the possible number of combinations can be freely and easily selected, high levels of expandability, identification power and handling facility can be achieved at a relatively low cost. This system can be applied to various articles such as information storage cards including magnetic cards, and keys. By using the system for verifying the authenticity of the article, an effective prevention of the counterfeiting of the article can be achieved.

Abstract: A system and method for testing bar code scanner window viability which determines whether the window is scratched or otherwise damaged enough to require replacement. The system includes a laser beam source. The laser beam passes through a window glass for scanning a bar code label. Light reflected from the bar code label passes through the window glass and is detected and converted into an electrical signal. Finally, a processor determines the bar code information from the electrical signal and determines whether the window glass is damaged enough that the bar code information cannot accurately be determined. The method determines the variance between the widths of the bars and spaces from a plurality of bar code scans and compares the variance to a predetermined threshold. The window glass is replaced when the threshold is exceeded.

Abstract: The invention relates to a guiding device for hand scanners which makes it possible to use such scanners with straight guidance, with uniform applied pressure, with uniform scanning speed and defined overlapping of scanned columns. For this purpose, the device has a device block, comprising a longitudinal guide rail with a longitudinal guide slot, guided in which is a guide frame, on which a carriage is mounted displaceably perpendicularly with respect to the guide slot and has a clamp or similar device for a scanner, and comprising a drive for adjusting the guide frame.

Abstract: A symbol code reader comprises a two-dimensional array of photosensitive elements for converting light scattered by the symbol code into image signals representative of the symbol code, image storage means for storing image signals produced by the photosensitive elements, and selection means for selectively passing image signals from the photosensitive elements to the image storage means. Preferably, the selection means are arranged for passing the image signals from predetermined sets of photosensitive elements, the elements of each set constituting a pattern in the array.

Abstract: An apparatus for illuminating and imaging a surface includes a two-dimensional array of LEDs for providing uniform illumination to the surface, the LEDs being mounted on a planar surface with a centrally defined aperture, and a CCD-based camera with appropriate lensing for obtaining an image of the illuminated surface and providing a signal representative of that obtained image to a processing unit, the CCD-based camera lensing being disposed through the centrally defined aperture in the planar surface of the LED array, and the LED array and CCD-camera lensing being disposed inside an opaque shroud.

Abstract: An apparatus for illumination and imaging of a surface includes an apparatus for illuminating the surface, an apparatus for obtaining an image of the illuminated surface and providing an output signal representative of the obtained image, and an apparatus for limiting the exposure time of the image-obtaining apparatus to a selected fast exposure time less than the video frame rate of the image-obtaining apparatus. The image-obtaining apparatus may be a CCD-based camera. The CCD-based camera and the illumination apparatus may be mounted in a shroud having an opaque side wall. A first polarizing film may be provided intermediate the illumination apparatus and the surface, and a second polarizing film, having a polarization orientation orthogonal to that of the first polarizing film, may be provided intermediate the surface and the image-obtaining apparatus.

Abstract: A hand-held optical scanner comprising a hand-displaceable scanner housing; scanner electrical components mounted within the housing for performing scanner operating functions; a battery disposed in the housing and electrically connected to the electrical components; a generator disposed in the housing and operatively associated with the battery; and a roller assembly mounted in the housing and drivingly linked to the generator.

Abstract: A guide for mounting on an optical scanner, said guide including a guide framework provided with a laterally extending guide arm having a straight edge bearing surface which cooperates with a bearing surface on the scanner housing whereby the scanner can be moved in a parallel relationship with the straight edge to prevent lateral movement of the scanner or unintentional rotation of the scanner for superior scanning capability. The guide arm is preferably received within a passage or channel in the framework for reciprocal, lateral movement to adjust the guide arm and hence the bearing surface to be in proper alignment with the bearing surface on the scanner. Double sided adhesive tape provides secure attachment and detachment from the scanner without mutilation of the scanner.

Abstract: A stacker system or an autoloader system includes a tape drive and one or more magazines which each include a plurality of tape cassettes or cartridges. A positioning system moves the magazine to a specific position to load or unload a particular cartridge or cassette from the magazine. A control system controls the operation of the tape drive and the magazines between a loaded and unloaded position. Each magazine includes a unique identification code which can be read by the stacker or autoloader to determine if the correct magazine has been inserted. In addition, each magazine includes a memory to record information about the contents of the recording media stored in the magazine or the performance of each recording media stored in the magazine.

Abstract: A method for identification of a roll and for determining its diameter, in which a device for reading the identifier and the sensor for measuring the diameter are mounted to a unit moving on a vertical lead, and its position is tracked by a position sensor. The diameter of the roll is detected by a mechanical detector that turns up when it contacts the surface of the roll enabling thus an uninterrupted movement of the unit past the measurement site. After the measurement of the diameter the identification unit moves to the center of the roll, inferred from the diameter, where the device for reading the identifier reads the identification code of the roll. During the return movement of the identification unit, markings can be made on the end of the roll by an ink-jet printer.

Abstract: An apparatus for scanning bar code data recorded on a target includes a source emitting a beam of radiation, and optics for deflecting the beam of radiation along an axis normal to the beam. The apparatus further includes an electronic shutter element defining a plurality of adjacent regions, each region independently capable of assuming a substantially transparent state, and, digital logic, for causing the adjacent regions of the shutter element to assume substantially transparent states in a sequential, directional manner along the axis to affect directional transmission of less than all of the deflected beam onto the target. The apparatus further includes a detector for sensing the presence of radiation reflected from the target, and, optics for converting the radiation reflected from the target into a beam and for focussing the beam onto the detector.

Abstract: Optical reader apparatus for reading data on a data carrier. A housing defines a data carrier slot having an optical data window at a prearranged position. An optical reading means is mounted within the housing for reading data scanned past the optical data window. A door assembly is mounted in a hinged relation to the housing means opposite the optical read window. The door has closed and open positions and permits access to the optical data window in the open position. The door assembly carries a resilient pressure spring. The resilient pressure spring urges a data carrier passing through the data carrier slot into optical reading contact with the optical data window. The door assembly mounts the resilient spring member within a frame for easy removability. The resilient pressure spring carries an optical compensation member on a forward surface thereof so that the optical compensation member is presented to the optical data window when a data carrier is not present.

Abstract: An optical scanning system comprises an optical scanner, a first circuit for generating a reference pulse and a second circuit for comparing a benchmark pulse scanned by the scanner to the reference pulse. The comparing circuit provides an indicating signal of one of a less than, a greater than and an equal to signals as a result of the comparison. There is a third circuit for adjusting sensitivity of the scanner based on the indicating signal. In one embodiment a visual indication is provided to distinguish between the less than, greater than and equal to signals so that a manual adjustment can be made to the scanner sensitivity. In another embodiment, automatic adjustments are made if a predetermined number of less than or greater than signals are provided before an equal to signal is provided by the comparing circuit.

Abstract: A barcode identification system is shown that includes a user operable personal computer for creating print jobs. The personal computer is coupled to a number of printers for printing the data for a job in a selected format on a record member such as a tag, label or the like. The system employs modular software. During the initialization of each of the software modules, the system determines whether the module includes a key identification that matches a system key and if not, the operation of the software module is limited to a demonstration mode if that mode is allowable. A data entry routine aids the user entering valid data for a selected format. In response to a print command, the data entered by the user is combined with the selected format to form a job. The job is then sent to a spooler which distributes the job to one of the barcode printers of the system.

Abstract: A symbol reader which projects an illumination window or field that is the same size as a field of view of a sensor used to read a symbol. The illumination window is aligned with the field of view of the sensor. The window or field can provide an area of relatively constant illumination or edges of the window or field can be at a higher illumination creating an outline or capture border. The outline alone can be projected when the ambient light level is sufficient for capture of the symbol. The window or field can be created by projecting light from various light sources.

Abstract: Dual-focus optical scanner for scanning an object, provided with optical illuminating means for illumating the object to be scanned with a light point derived from a light source, which illuminating means have their own optics, and with optical imaging means for imaging the object onto a point sensor, which imaging means have their own optics. Said illuminating means and said imaging means are embodied in a coaxial relation with substantially coincident optical axes. The focal plane of the illuminating optics and the focal plane of the imaging optics in the object area are slightly spaced, the separation of said two spaced focal planes being such that the working range of the scanner is the sum of the depths of field of the illuminating and imaging optics, defined according to required spatial resolution. Said optical scanner can be used as a wandtype symbol code reader, such as a bar code reader, for reading the symbol code by relative manual scan movement.

Abstract: A tip assembly for a bar code scanner having a concentric design which prevents rotational, axial and tilting movement among the components of the tip assembly. A tip housing with an internal detent is snap fitted over a scanner housing having multiple cantilevered, flexible beams, each with a circumferential groove adapted to receive the detent therein. An optical assembly housing containing optics is received within the scanner housing, between the flexible beams thereof. The optical assembly housing has tabs extending outwardly to mate with corresponding recesses in the beams to prevent rotation of the optical assembly relative to the scanner housing. The tip housing is sized to frictionally engage and press the beams inward so they frictionally engage the optical assembly housing. A scanner barrel is positioned about the scanner housing and extends to a position outward of the lip portion of the tip housing to prevent outward travel of the beams, thus locking the tip assembly components securely together.

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: An identification mark comprises a set of a plurality of mark elements. One mark element is divided into a large number of first and second fine square regions alternately arranged. One or two basic gratings selected from a plurality of types of basic gratings is/are drawn in both fine square regions, so that patterns are formed. Since the basic gratings are different in direction of the grating or spatial frequency, the types of the basic gratings are different from each other. One selected type of basic gratings is drawn in all first fine square regions. Similarly, the one or another type of basic gratings is drawn in all second fine square regions. At least one first fine region and at least one second fine region exist in the diameter of the light beam when light is radiated on the mark element for optical read. Thereby, types of patterns, which one mark element can obtain, are increased.

Abstract: To prevent unauthorized duplication of an information storage cards such as magnetic cards, IC cards, and optical cards, the card carries an identification region which may be identified by a simple optical sensor. The identification region may consist of holograph, diffraction grating, a multiplicity of parallel grooves and other processed surfaces having certain reflective or transmissive directivities. In particular, the identification region comprises a plurality of segments having two or more different reflective or transmissive directivities, and these segments are uniformly distributed in the identification region so that all of the segments may be accessed simultaneously by the optical sensor which comprises a light emitter and a light receiver including a plurality of parts each capable of individually detecting light reflected by or transmitted through the identification region.