Abstract: An excess heat-generating element is coupled to a heat sink through a heat conduction path. A thermal switch is mounted in the heat conduction path. A temperature-sensitive element is coupled to the heat conduction path on a same side of the thermal switch as the excess heat-generating element. A temperature monitor is mounted adjacent the temperature-sensitive element. A temperature controller has an input coupled to the temperature output of the temperature monitor and an output control line coupled to an input of the thermal switch. The temperature controller switches off the thermal switch, in response to detecting a temperature below a temperature threshold from the temperature output. When the thermal switch it off, it impedes heat flow from the excess heat-generating element to the heat sink, and the heat flow is redirected to increase heat flow from the excess heat-generating element to the heat-sensitive element.

Abstract: An optical rotary joint for optical signal transmission is described, said optical rotary joint having at least two units that are respectively rotatably mounted about an axis of rotation, the axes of rotation of which, at least in sections, have a lateral distance from one another. The invention is distinguished by a rotary transformer that is embodied in the form of an endless loop respectively resting in a circumferential manner on both units along a contact region and positively coupling the at least two units with one another in a rotationally movable manner. Attached to both units is respectively one optical unit for conjoint rotation, said optical unit comprising at least one optical signal line, a beam splitter and/or beam coupler, which is optically coupled to the at least one optical signal line, and at least two optical partial signal lines, said optical unit being optically coupled to the at least one optical signal line via the beam splitter and/or beam coupler.

Abstract: A system for processing printed products includes a transfer station which is provided with an infeeding location for infeeding printed products to the transfer station from a delivery station. The transfer station further comprises a number of connecting locations and a removal location. To each of the connecting locations is connected a processing station. An output station is connected to the removal location. The transfer station is further provided with a transporting device for moving the printed products within the transfer device between the infeeding location, the various connecting locations and the removal location. The printed product infed to the transfer station at the infeeding location is transported in any sequence from the transfer station to one of the processing stations. After completion of the processing operation in a particular processing station, the printed product is moved back to the transfer station.

Abstract: In an example, a method of communication includes receiving a data set comprising a plurality of data items, and analyzing the data set to determine a plurality of distinct data values of the plurality of data items. The method also includes associating, based on the analysis of the data set, each distinct data value with a respective wavelength among a plurality of wavelengths. The method further includes transmitting each data item, one data item at a time, as an optical signal at the wavelength associated with the distinct data value of the data item.

Abstract: A portable device (10, 20) includes at least a control element (14, 24, 34) for receiving command signals and a reader (12, 22, 32). A detection element (18, 28, 38) is connected with the control element (14, 24, 34) and they communicate with each other. Operation of the reader (12, 22, 32) in relation to the object to be identified is controlled through command signals so that at least one of the command signals received by the control element (14, 24, 34) is based on information indicating movement or position received from the detection element (18, 28, 38). The reader (12, 22, 32) is easy to use and quick to operate in its operating environment as no separate actions are required of the user in order to initiate operations.

Abstract: An imaging system includes a detector for receiving electromagnetic energy and generating sampled data in accordance with the electromagnetic energy so received. The detector is characterized by a threshold point such that the sampled data is in one of two states: i) below threshold, when the intensity of the electromagnetic energy so received is less than the threshold point; and ii) above threshold, when the intensity of the electromagnetic energy is greater than the threshold point. The imaging system also includes saturation optics for providing a characteristic of the sampled data, wherein the characteristic of the sampled data when below threshold is different from the characteristic of the sampled data when above threshold.

Abstract: In the automatic analyzer, the height of the test tubes is measured using the function of the optical information reader installed for discrimination of a sample. Various sensors installed so as to measure the height of the test tubes of the automatic analyzer can be omitted and decrease in cost, improvement of reliability, and improvement of maintenance capacity result.

Abstract: The invention relates to a detection system and a detection method for the detection and tracking of optical codes on objects which are transported along a monitored zone, comprising a plurality of optoelectronic sensors to read the codes and to generate corresponding reading data and comprising at least two data buses, each having its own associated bus control unit, wherein each of the plurality of sensors is connected both to the one and to the other of the two data buses and wherein the one of the two data buses with the associated bus control unit, on the one hand, and the other data bus with the associated bus control unit, on the other hand, are divided into a primary branch and a secondary branch which is subordinate to the primary branch.

Abstract: A reference frame provided in a vacuum chamber is supported by support pillars extending through and isolated from the vacuum chamber walls to isolate the reference frame from vibrations in the vacuum chamber. The gap between the support pillar and the vacuum chamber wall may be sealed by a low-stiffness seal. The low stiffness seal may be a three part seal allowing relative motion in six-degrees of freedom.

Abstract: A system for illuminating and reading information on a target (12) includes an illuminating device (14) for illuminating the target, separate from the illuminating device a user wearable reader device (11) for capturing an optical image of the target when illuminated by the illuminating device, detector means (30, 35) for detecting the location of the reader device and adjustment means (36, 22) for adjusting the illumination provided by the illumination device in response to a signal provided by the detector means so that a region (33) on the target illuminated by the illuminating means is readable by the reader device. A method of use of the system and an illumination unit for use in the system are also described.

Abstract: An optical code reader for reading optical codes in any orientation with a preferred depth of field (DOF), the optical code reader including imaging sensor arrays arranged at angles to one another and tilted in accordance with the Scheimpflug principle to allow for omni-directional reading and a preferred DOF. In addition, an optical code reader may also include an optical device to rotate an image as it is projected upon a stationary tilted image sensor array. Still further, an optical code reader may include a rotating imaging sensor array tilted in accordance with the Scheimpflug principle to allow for omni-directional reading with a preferred DOF.

Abstract: The invention relates to a detection system and a detection method for the detection and tracking of optical codes on objects which are transported along a monitored zone, comprising a plurality of optoelectronic sensors to read the codes and to generate corresponding reading data and comprising at least two data buses, each having its own associated bus control unit, wherein each of the plurality of sensors is connected both to the one and to the other of the two data buses and wherein the one of the two data buses with the associated bus control unit, on the one hand, and the other data bus with the associated bus control unit, on the other hand, are divided into a primary branch and a secondary branch which is subordinate to the primary branch.

Abstract: The present invention provides an optical apparatus comprising an optical gain correction filter having a multilayer film structure formed by stacking a plurality of thin films with different diffractive indexes on a light transmitting board, wherein when the light with the wavelength &lgr; enters at the incident angle &thgr;, the transmissivity is assumed to be T1(&lgr;, &thgr;)(0≦T1(&lgr;, &thgr;)≦1), and the thickness and stacking state of each thin film of the optical gain correction filter are adjusted to increase the transmissivity T1 (&lgr;0, &thgr;) when the incident angle &thgr; increases close to the predetermined maximum incident angle &thgr;max with respect to the incident light with the wavelength &lgr;0. The optical apparatus is applied to a bar code reader.

Abstract: This small, inexpensive, non-contact laser sensor can detect the location of a retroreflective target in a relatively large volume and up to six degrees of position. The tracker's laser beam is formed into a plane of light which is swept across the space of interest. When the beam illuminates the retroreflector, some of the light returns to the tracker. The intensity, angle, and time of the return beam is measured to calculate the three dimensional location of the target. With three retroreflectors on the target, the locations of three points on the target are measured, enabling the calculation of all six degrees of target position. Until now, devices for three-dimensional tracking of objects in a large volume have been heavy, large, and very expensive. Because of the simplicity and unique characteristics of this tracker, it is capable of three-dimensional tracking of one to several objects in a large volume, yet it is compact, light-weight, and relatively inexpensive.

Abstract: A surveillance system uses pulsed laser near infrared light to illuminate a retroreflecting tag attached to a target for providing a return image that pulsates and that can be monitored by a camera for covert tracking of a target. The surveillance system may instead use pulsed near infrared polarized laser light to illuminate a transparent ¼ waveplate tag affixed to a moving vehicle or transitory containers for monitoring enhanced return images reflected from the tags serving to change the polarization of the illuminating laser beam so as to provide a co-located camera with return images that pulsate relative to background images for enhanced viewing and surveillance of the vehicle or container.

Abstract: An optical scan module, for example for an optical scanner, includes an integrally molded plastics material member which defines not only the laser focusing lens, but also the laser focusing aperture and the collection mirror. In addition, the molded member may act to house and to locate both a semiconductor laser and a photodetector, thereby ensuring easy and accurate placement of those elements within the scanning assembly. The optical assembly may be in modular form, mounted onto a common printed circuit board with a beam scanner.

Abstract: An optical reader for reading optical indicia which includes an imaging element for forming an image of the optical indicia at an image plane. The optical reader further includes an aperture positioned at the image plane and having a width smaller than the width of a smallest element in the image to be discerned by the optical reader, the aperture permitting illumination from a portion of the image to impinge upon a photodetector. The optical reader further includes a displacement system which produces relative movement between the image and the aperture to produce an output of the photodetector indicative of the optical indicia.

Abstract: A method and apparatus for reading bar codes or other images while reducing or eliminating the need for self-generated illumination. An image reader is preferably embodied as a handheld unit and comprises an efficient optical collection system including an aperture with a high aspect ratio and/or a multi-focal lens or lenses. An optically transmissive spacer affixed to the front of the handheld unit allows ambient light to be collected at close range, and a diffuser may be used to reflect ambient light from the handheld unit to provide additional illumination at close range. A masked CCD detector with rectangular pixels receives collected light and is coupled to an adaptive exposure circuit for preventing saturation of the CCD detector at high illumination levels. A correlated double sampling circuit coupled to the adaptive exposure circuit rejects common mode noise and allows operation in lower light levels.

Abstract: An optical assembly for use with optoelectronic readers. An imaging optical assembly having an imaging optical axis forms an image of a two-dimensional region on an optoelectronic imaging device. An aiming pattern generator including at least a point-like aiming light source and an interferometric pattern generating optical element project onto the two-dimensional region a luminous aiming pattern that approximately coincides with the field of view of the imaging device. The aiming optical axis of the aiming pattern remains approximately coincident with the field of view of the imaging device over the range of reader-to-target distances over which the reader is used.

Abstract: A method and apparatus for reading bar codes or other images while reducing or eliminating the need for self-generated illumination. An image reader is preferably embodied as a handheld unit and comprises an efficient optical collection system including an aperture with a high aspect ratio and/or a multi-focal lens or lenses. An optically transmissive spacer affixed to the front of the handheld unit allows ambient light to be collected at close range, and a diffuser may be used to reflect ambient light from the handheld unit to provide additional illumination at close range. A masked CCD detector with rectangular pixels receives collected light and is coupled to an adaptive exposure circuit for preventing saturation of the CCD detector at high illumination levels. A correlated double sampling circuit coupled to the adaptive exposure circuit rejects common mode noise and allows operation in lower light levels.

Abstract: The invention relates to an optoelectronic sensor, in particular a bar code reader, with an optical receiving system positioned in front of a light receiver for the deflection of a light beam reflected from an object, in particular a bar code, onto the light receiver. Through the provision of aperture diaphragms, or a plurality of light receivers, or regions with different image forming characteristics in the optical receiving system, a situation is achieved in which the receiving characteristics of the overall system, which result by reason of the shape of the sensing laser beam, as a result of the characteristics of the electronic evaluation system and as a result of different light intensities of the light returned, for example from a bar code, are optimized for different sensing distances.

Abstract: This small, inexpensive, non-contact laser sensor can detect the location of a retroreflective target in a relatively large volume and up to six degrees of position. The tracker's laser beam is formed into a plane of light which is swept across the space of interest. When the beam illuminates the retroreflector, some of the light returns to the tracker. The intensity, angle, and time of the return beam is measured to calculate the three dimensional location of the target. With three retroreflectors on the target, the locations of three points on the target are measured, enabling the calculation of all six degrees of target position. Until now, devices for three-dimensional tracking of objects in a large volume have been heavy, large, and very expensive. Because of the simplicity and unique characteristics of this tracker, it is capable of three-dimensional tracking of one to several objects in a large volume, yet it is compact, light-weight, and relatively inexpensive.

Abstract: A beam projecting apparatus which includes a light source emitting a laser beam; and a beam projecting device which includes a beam projecting portion from which the laser beam is projected outwardly so that the laser beam has a beam waist position at a predetermined position apart from the beam projecting apparatus. The beam projecting apparatus further includes a beam waist position adjusting optical system which is disposed along a light path from the light source to the beam projecting portion, at least one lens element of the beam waist position adjusting optical system being movable along an optical axis thereof; a temperature detecting device for detecting a temperature in the beam projecting apparatus; and a controller for controlling a movement of the at least one lens element in association with the temperature detected by the temperature detecting device so that a deviation of the beam waist position from the predetermined position due to a temperature change is minimized.

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: An optical system and method for data reading in which a light source generates an optical beam directed toward an object to be read and a variable aperture mechanism positioned in the outgoing light path establishes at least two separate focal planes. The variable aperture device may comprise a variable aperture system in which the size of the aperture is selectively varied about a range within the diffractive limit of the light beam. A preferred aperture mechanism is an electronically actuable mechanism with no moving parts which may include a liquid crystal aperture with one or more aperture regions which are selectively or consecutively activated. The optical system therefore establishes two or more separate waist locations from a single light source resulting in greater depth of field or multiple depths of field.

Abstract: A high speed imaging apparatus for CCD based scanners comprises a housing having separate compartments which complement modular assemblies installed therein. A decoder compartment houses components associated with locating and decoding an image. An optics compartment houses the mirrors and associated optics for reflecting the subject image onto the CCD detector. A lighting compartment includes high intensity lamps and the associated components for illuminating an object to be imaged. The lighting compartment includes a heat management system which removes the heat from the high intensity lamps and prevents heat from migrating to other compartments within the housing.

Abstract: A method and apparatus for reading bar codes or other images while reducing or eliminating the need for self-generated illumination. An image reader is preferably embodied as a handheld unit and comprises an efficient optical collection system including an aperture with a high aspect ratio and/or a multi-focal lens or lenses. An optically transmissive spacer affixed to the front of the handheld unit allows ambient light to be collected at close range, and a diffuser may be used to reflect ambient light from the handheld unit to provide additional illumination at close range. A masked CCD detector with rectangular pixels receives collected light and is coupled to an adaptive exposure circuit for preventing saturation of the CCD detector at high illumination levels. A correlated double sampling circuit coupled to the adaptive exposure circuit rejects common mode noise and allows operation in lower light levels.

Abstract: An optoelectronic device for identifying a mark having a defined contrast pattern includes a transmitting element for emitting a beam of transmitted light. A deflector unit periodically guides the transmitted light beam over the mark. A receiving element receives the transmitted light beam after being reflected by the mark and produces an analog received signal which exhibits an amplitude modulation impressed by the contrast pattern of the mark and is dependent on the spatial intensity distribution of the transmitted light beam. An n-bit analog-digital converter has a word width greater than 1 for converting the analog received signal into a digital received signal. A digital filter includes an input for receiving the digital received signal.

Abstract: A method and apparatus are provided for reading bar codes or other images while reducing or eliminating the need for self-generated illumination. An image reader comprises an efficient optical collection system including an aperture with a high aspect ratio and/or a multi-focal lens or lenses. A CCD detector receives collected light and is coupled to an adaptive exposure circuit for preventing saturation of a CCD detector at high illumination levels. A correlated double sampling circuit receives the output of the CCD detector to allow lower light levels to be detected by the system. The correlated double sampling circuit is connected to a signal processing block which uses a derivative based technique for enhanced edge detection. Edge detection information may be provided to a decoder for decoding. Various other embodiments may utilize some but not all of the above elements, or may include additional refinements, while obtaining the benefit of reducing or eliminating the need for self-generated illumination.

Abstract: A bar code scanner comprises a radiant energy source for generating a radiant energy beam of a given configuration, a detector for generating output electrical signals indicative of radiant energy incident thereon, an optical system having a focus portion for transmitting segments of the radiant energy beam in separate optical paths extending from the scanner to a bar code to be scanned and a scan portion for collecting radiant energy transmitted by the focus portion as modified by the bar code and applying the same to the detector and a decoder for decoding the output electrical signals of the detector to provide indication of information contained in the bar code.

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: A system for bar code reading and scanning is provided having automatic bar code signal size control. The scanner includes a processor which calculates, in response to a signal power level of the symbol which has been read, a first optical power level when the beam is scanned in a first direction and a second optical power output level when the beam is scanned in a second direction. This calculation is responsive to the power level and the detected signal size of the preceding scan.

Abstract: An elongated, flexible, generally planar spring used for mounting an oscillatable scanning component in an electro-optical scanning module for reading coded indicia is rendered resistant to over flexing during scanning by receiving a pin with radial clearance in an oversized opening, thereby attenuating the effects of external shock forces to the module.

Abstract: A digital signal output device including a revolving shaft, a transparent gear wheel fixedly mounted around the revolving shaft and turned by it, the transparent gear wheel having a plurality of teeth alternatively spaced by gaps around the periphery and an annular sloping wall at one side around the center, and a plurality of photoelectric inductors spaced from the periphery of the transparent gear wheel and arranged in parallel, wherein when the transparent gear wheel is turned by the revolving shaft, the light of the light source is projected onto the sloping wall of the transparent gear wheel and reflected radially through the teeth and/or gaps of the transparent gear wheel onto the photoelectric inductors, causing the photoelectric inductors to be or not to be triggered, and therefore the amplification circuit which is connected to the output ends of the photoelectric inductors is driven to provide a digital output signal corresponding to the revolving direction and amount of movement of the revolving sh

Abstract: An optical system and method for data reading in which a light source generates an optical beam directed toward an object to be read and a variable aperture mechanism positioned in the outgoing light path establishes at least two separate focal planes. The variable aperture device may comprise a variable aperture system in which the size of the aperture is selectively varied about a range within the diffractive limit of the light beam. A preferred aperture mechanism is a liquid crystal aperture with one or more aperture regions which are selectively or consecutively activated. The optical system therefore establishes two or more separate waist locations from a single light source resulting in greater depth of field or multiple depths of field.

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 hand held bar code scanning device includes scanning circuitry to conduct bar code scanning and a manually actuated optical trigger switch, connected to the scanning circuitry, to initiate bar code scanning.

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 hand held bar code scanning device includes scanning circuitry to conduct bar code scanning and a manually actuated optical trigger switch, connected to the scanning circuitry, to initiate bar code scanning.

Abstract: A system for reading two-dimensional code marks on an article includes a camera for imaging the marks and signal processing means coupled to the camera for processing information contained in the marks. The article bears code marks in a fixed-size marking zone on the article surface. Each of the code marks has a pattern of light and dark areas. The code marks are arranged in a matrix patterned unit block; the matrix may be a single row or column as well as rectangular or truncated rectangular. The unit block includes at least one position code which in turn includes code marks denoting an address code, a start code, an end code, and a line feed code. The code marks are preferably each a block of four squares, with each square being bisected by a respective diagonal line to form two triangles. Each triangle in a square may be differently colored (light or dark).

Abstract: An optical reader, such as a bar code reader, includes improved circuitry to enable the bar code reader to respond more quickly and more accurately to signal variations due to changes in the ambient light condition and in the contrast presented by the information being read. In particular, the reader includes "slice" circuitry to sense the transitions of signals corresponding to the black-to-white and white-to-black edges of a bar code. The slice circuit includes two ideal diodes whose inputs are connected to an analog input terminal and whose outputs are respectively connected to first and second capacitors to sense and peak detect the values ofincreasing and decreasing signals. Two diodes are connected in series between the postive peak detector and the negative peak detector and the junction of the two series connected diodes functions as an output terminal at which is produced a reference voltage applied to a comparator.

Abstract: An optical data reader including a device for producing a light beam, and a device for changing a condensing position of the light beams before the light beam is reflected from a target such as a bar code. The device for changing the condensing position is either a variable focus lens or mirror, each adapted to change the curvature of the surface of the lens or mirror in order to move the condensing position cyclically and continuously. The variable focus mirror changes the shape of its reflecting surface in response to electrical signals from a driving circuit. Excess pressure within the mirror caused by the mirror surface being attracted inwards is expelled through intake/outlet ports formed in the drive electrode. The variable focus lens alters the focal length of the lens each time the curvature of the surface thereof is changed. Preferably, the curvature of the lens surface is changed by increasing fluid pressure within the lens, while the curvature of the variable focus mirror is electrically driven.

Abstract: A portable symbology reader utilizing an anamorphic lens system. The anamorphic lens system allows a low cost, high volume CCD sensor to be used in a hand-held, point and shoot, portable imaging system. The anamorphic lens system provides vertical sensor resolution equal to the horizontal while providing a maximum field of view.

Abstract: An optical system and method for data reading in which a light source generates an optical beam directed toward an object to be read and a variable aperture mechanism positioned in the outgoing light path establishes at least two separate focal planes. The variable aperture device may comprise a variable aperture system in which the size of the aperture is selectively varied about a range within the diffractive limit of the light beam. A preferred aperture mechanism is a liquid crystal aperture with one or more aperture regions which are selectively or consecutively activated. The optical system therefore establishes two or more separate waist locations from a single light source resulting in greater depth of field or multiple depths of field.

Abstract: A photonic system for compressing and decompressing data using a hologram that converts a plurality of spatially modulated light beams into a single reference beam that has a wavelength unique to a bit string of data. The single reference beam is then converted into a plurality of spatially modulated light beams by a diffraction grating. The light beams are detected by a bank of photodetectors which convert the photonic energy into electrical signals that correspond to the originally transmitted bit string.

Abstract: A optical system having optically encoded information includes a microptic multiplet (MOM) optical system on compact arrays or cards for both secure (encrypted) and non-secure applications where the presence or position of optical micro-lenses is indicative of the encoded information. The system is characterized by a first microptic lens module (MLM) that has data optically encoded thereon based on the position of a lenslet in a lenslet cell. One or more additional microptic lens modules can be used as a key(s) to interpret the data.

Abstract: An information processing apparatus such as an optical disc device which is provided with an integrated photo detector for transducing a reflected light beam from an optical information medium to an electric signal. The integrated photo detector used in the apparatus comprises a substrate; an optical guide formed on the substrate; and a plurality of integrated photo detecting sections each including a grating coupler for guiding the reflected light beam to the optical guide, and a photo detecting unit for detecting a guided light beam in the optical guide. The use of this integrated photo detector results in increasing error tolerance relative to incident angle and incident position to improve the incidence efficiency, thereby elevating the reliability of the apparatus.

Abstract: A bar code is scanned to generate a signal which is representative of the bar code and contains a series of maxima and minima. The signal is sampled to detect the maxima and minima corresponding to the encoded information of the bar code. The detected maxima are compared with an upper threshold value while the detected minima are compared with a lower threshold value. For each detected maximum and minimum, a "0" or "1" is entered in a memory depending upon whether or not the detected maximum or minimum exceeds the corresponding threshold value. This produces an array of bits which is then decoded.

Abstract: A high speed imaging apparatus for CCD based scanners comprises a housing having separate compartments which complement modular assemblies installed therein. A decoder compartment houses components associated with locating and decoding an image. An optics compartment houses the mirrors and associated optics for reflecting the subject image onto the CCD detector. A lighting compartment includes high intensity lamps and the associated components for illuminating an object to be imaged. The lighting compartment includes a heat management system which removes the heat from the high intensity lamps and prevents heat from migrating to other compartments within the housing.