Abstract: A scribe mark reader (10) uses a source of circularly polarized light and a holographic beam-shaping optical element (40) to uniformly illuminate an area of a substrate (20) that includes a scribe mark (18). Light incident on the substrate at a scribe mark is predominantly scattered, whereas light incident on the substrate at a processed area (30) of the wafer surface between the pits (28) of the scribe mark is predominantly specularly reflected. The phase-reversed, specularly reflected light from the processed area is blocked by a circular analyzer that passes light scattered from the scribe mark. Light passing the polarizer can then be used to form an image of the scribe mark. The intensity of the images formed are sufficiently consistent that the automatic gain control of the CCD camera can be used and the images formed can be readily interpreted by optical character recognition software.

Abstract: A system and method for scanning a bar code target by continuously varying the focal range of a bar code scanning system. A light source is provided for generating light rays, and a lens is provided for focusing the light rays. The lens has a variable focal length. The focused light rays are scanned across the bar code target with a beam scanner. While the focused light rays are being scanned, the focal length of the lens is continuously varied.

Abstract: A scanner interface is operatively connected to an electro-optical scanner for scanning bar code symbols. A status/condition interface is operatively connected with a system component, e.g., a photodetector, a decoder, a battery, etc., whose status/condition is to be monitored. Threshold information about the system component is stored in a memory. A system processor generates updated information about the system component during scanning, compares the updated information with the threshold information and generates an output signal upon such comparison. In response to the output signal, an indicator signals a user as to the status/condition of the system component.

Abstract: A bar code scanner system includes a laser light source that periodically produces a light beam that is swept across a bar code label. The laser light source is periodically turned "on" and "off" according to a duty cycle. A detector produces a first electric signal representative of received bar code label reflected light and ambient light when the laser light source is on, and produces a second electric signal representative of received ambient light when the light source is "off". A demodulator circuit, coupled to the detector, provides a first gain to the first electric signal and provides a second gain to the second electric signal. The gains applied are selected such that the signal and signal component produced solely as a result of the ambient light will significantly cancel out one another when the signals are combined. A filter, coupled to the demodulator circuit, receives the electric signals from the demodulator circuit and reduces out-of-band signal components such as noise.

Abstract: An electronic apparatus having a plurality of states, and including a detection mechanism for detecting an external light and outputting a detection signal indicative of an intensity of the external light, a transition mechanism for making a state transition from a first state to a second state which is different from the first state and vice versa depending on the detection signal, and a varying mechanism for varying a light detection sensitivity of the detection mechanism depending on the detection signal when the state transition is made by the transition mechanism.

Abstract: A system for bar code reading and scanning is provided having automatic bar code signal size control. In the first embodiment of the system, a processor selects on successive scans of a bar code one of a plurality of different optical power levels from a laser diode which provides a light beam illuminating the bar code. This selection is responsive to the size of the signal from a photo-detector which receives returned light from the bar code during scanning. The signal size is detected by a signal size detecting circuit, and is measured by the processor during scanning. In a second embodiment of the system, the processor calculates an optical power level after every two consecutive scans across the bar code. The laser power level is calculated differently for alternative scans occurring in different orders (even or odd counting from the first scan).

Abstract: An exposure control apparatus for use with optical readers, such as bar code readers, which utilize photosensitive image sensors. An illumination signal generating circuit generates an illumination signal having a magnitude that varies in accordance with the time averaged value of the illumination level at the image sensor. A window detecting circuit periodically samples the illumination signal to determine if that signal is or is not within a window of acceptability. Exposure period determining circuitry uses the output of the window detecting circuit to upwardly or downwardly adjust the value of a control variable as necessary to cause the illumination signal to approach, enter and remain within the window of acceptability.

Abstract: In an optoelectronic recording element for point-by-point and line-by-line recording, the recording element is composed of a laser diode for generating a light beam, of an objective, of a light detector arranged spaced from the laser diode and of a reflector arranged turned in the beam path of the light beam that reflects a part of the light beam onto the light detector. The reflector is composed of concave mirror segments that are positioned between the laser diode and the objective. The reflector has an aperture whose center line coincides with the optical axis and whose diameter at least corresponds to the diameter of the light part of the light beam employed for the recording. As a result thereof, the light part of the light beam employed for the recording passes through the reflector loss-free, and the light part of the light beam that is not used is nearly completely focussed onto the light detector.

Abstract: The apparatus for reading a symbol of a 2-dimensional code has a diffusion plate and a diffuse reflection surface between a light source unit and an opening to prevent light emitted from the light source unit from directly reaching the opening. Illumination light from the light source unit reaches the diffuse reflection surface while the central axis of the light is shifted from the optical path to the diffusion plate. With this arrangement, nonuniformity of illumination light irradiated on a a symbol on object can be prevented, and a halation of light can be prevented. The symbol of the 2-dimensional code can therefore be accurately read.

Abstract: A hand held label reader is capable of illuminating a label, capturing a digital image of two-dimensional information indicia on the label, and decoding the digital image to provide decoded output data to a terminal. The target label is illuminated by a low variation illuminator that includes a circular LED array mounted behind a plano-concave dispersing lens. The automatic electronic camera, which includes a CCD camera and control circuitry, uses three images to adjust the intensity of the digital image and store a properly exposed image of the label in video RAM. The intensity of the digital image is adjusted by controlling the video system gain via adjusting the CCD array's integration time, the gain of a video amplifier, and the gain provided by an analog-to-digital converter. The gain provided by the analog-digital-converter is adjusted to compensate for the attenuation of light through the camera's lens assembly. For the first image, the digital image is obtained using a default setting for the gain.

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 bar code scanning engine is disposed in a housing with a device that tracks the movement of the housing over a surface displaying symbols, such as bar codes, and provides an integrated bar code reading and locating assembly, commonly known as a mouse. When the mouse is in proximity to the bar code on the surface over which is tracks, switches on the mouse are actuated and circuitry in the mouse associated with the device and with the scanning engine initiates scanning, and provide outputs representing the location of the mouse on the surface and the bar code. The circuitry may be adapted to enable bar code scanning only when the mouse is located at selected positions on the surface where bar codes are expected to be found. The entire mouse assembly may be lifted from the surface and operated in a manner similar to a tethered hand-held bar code scanner using switches and scanner engine.

Abstract: An extended working range dataform reader with reduced power consumption having a camera assembly and a circuit control board including game control circuitry and exposure control circuitry configured to set an initial gain value and an initial exposure period, respectively, resulting from a previous dataform reading session. Subsequent fields of image data are captured by the camera which are used to correct the gain and exposure relative to the initial values for gain and exposure period, thereby reducing the latency period for realizing correct values and reducing power consumption during power up. Furthermore, the gain control system and the exposure control system each utilize an open loop feedback such that successive fields of image data captured by the camera are utilized to calculate correct values, thereby reducing the latency time for realizing a correct value.

Abstract: A casing, including a grip portion and a head portion, houses a pair of light sources for illumination, an image sensing device, an optical system for forming an image on the image sensing device, a photosensor for detecting the luminance of symbol reading area, a signal processing circuit, and a light quantity detection circuit. The housing extends from the head portion towards the symbol reading area. An ambient light window is provided in the housing for introducing ambient light into the symbol reading area. A light source driving circuit controls an amount of light emitted by the light source, by increasing or decreasing the amount of light, such that the combined ambient light and light source illumination is between predetermined levels.

Abstract: A bar code scanner comprises a first collection optical system having an optical axis and a first magnification, a detector disposed along the optical axis and in optical communication with the first collection optical system, a second collection optical system having a second magnification greater than the first magnification and having an optical axis and displacing means operable for selectively moving the second collection optical system to dispose the optical axis thereof in coincidence with the optical axis of the first collection optical system.

Abstract: A unitary hand-held bar code scanner and reader produces an elliptical beam, oriented with its major axis along the direction of the bars, utilizing optics employing far field diffraction effects to shape the beam and maintain its elliptical aspect (length to width ratio) constant over a distance in front of the scanner were bar codes may be located. The optics eliminates parallax even though the photodetector and light source (preferably a laser diode) are located offset from each other on a board on which the optics are mounted. A housing assembly has channels which mount the board therein without shock absorbing devices. A digital microcomputer controller and peripheral devices regulate the optical power output from the laser diode and prevents catastrophic failure, if the electrical current through the laser diode exceeds safe limits.

Abstract: A low profile optical unit for use in a 2D bar code reader. A vertically disposed light redirecting panel having contoured reflective openings therein is mounted in the front of the unit and an LED behind the panel. Light emitting diodes for illuminating a target are mounted on the LED board behind the contour openings whereby direct light and reflected light illuminates a target. An imager housing is mounted on the back of the LED board and contains a recess that passes through the back of the housing and a lens barrel that extends forward through holes provided in the LED board and the light redirecting panel. An imager board is secured to the back of the housing which holds a 2D imager that is contained within the housing recess. Circuitry for generating image data signals is mounted on the back of the imager board. A lens holder is threadably mounted in the lens barrel which contains a lens system having a short back focal length for focusing a target image on the imager.

Abstract: A scribe mark reader (10) uses a source of circularly polarized light and a holographic beam-shaping optical element (40) to uniformly illuminate an area of a substrate (20) that includes a scribe mark (18). Light incident on the substrate at a scribe mark is predominantly scattered, whereas light incident on the substrate at a processed area (30) of the wafer surface between the pits (28) of the scribe mark is predominantly specularly reflected. The phase-reversed, specularly reflected light from the processed area is blocked by a circular analyzer that passes light scattered from the scribe mark. Light passing the polarizer can then be used to form an image of the scribe mark. The intensity of the images formed are sufficiently consistent that the automatic gain control of the CCD camera can be used and the images formed can be readily interpreted by optical character recognition software.

Abstract: A stationary data symbol reader includes a CCD, lens, CCD drive circuit, amplification circuit, binarization circuit, memory, CPU, light sources, light source drive circuit, communication driver, switch circuit and trigger switch. When reading, a frame image capture is carried out, and a number of picture elements of the fields of the frame corresponding to the displacement of an authenticator pattern (associated with the data symbol) between a second field image and a first field image is calculated. The moving speed of the data symbol is calculated from the displacement. The optimal light exposure time is calculated from the moving speed, and the optimal intensity of illumination is calculated from the exposure time.

Abstract: A lighting apparatus includes: a plurality of light emitting diodes; a printed circuit board on which the light emitting diodes are arranged in one row; and a rod-like projection lens disposed in front of the light emitting diodes along a light emitting direction, for irradiating an object with light in a strip-like manner. Each of the light emitting diodes is a chip-type light emitting diode which has a substantially parallelpiped shape and which comprises a light-emitting face and a pair of electrode faces. The light-emitting faces are in a plurality of planes which are perpendicular to one common plane, respectively. An optical information reader has the lighting apparatus.

Abstract: A radiant energy source, e.g., solar energy, is employed to power an electro-optical reader, preferably by charging an on-board battery. A solar light collector is mounted on the reader in a location exposed to ambient light.

Abstract: A projector projects an image. A scanning mirror deflects the projected image by mirror oscillation method. A reading device reads the projected image deflected by said scanning mirror and outputs an image data corresponding to the projected image. A discriminating device discriminates which projection lens is mounted on said projection lens mount among said plurality of lenses. A memory device stores respective distortion data of said plurality of projection lenses and distortion data concerned with a distortion being due to the oscillation method. A correcting device corrects distortion of the distortion data of the projection lens which is discriminated to be mounted on the projection lens mount and the distortion data concerned with a distortion being due to the oscillation method.

Abstract: An optical reading apparatus (bar code reader) including a plurality of light emitting elements, each light emitting element emitting light in different directions onto an information recording surface which has a linear recording (bar code pattern) printed thereon. A light receiving element receives reflected light from the information recording surface and generates a recording medium read signal for each light emitting element which is transmitted to a signal processing section. The signal processing section includes a plurality of conversion processing routes for converting the recording medium read signals from the plurality of light emitting elements into a plurality of display signals. Each of the display signals is then decoded separately.

Abstract: A code reader, for reading a code printed on a surface of a printing medium, includes a photoelectric device for converting light reflected from the code into an electric signal. An amplifier is provided for amplifying the electric signal converted by the photoelectric device. A gain adjusting device is provided for adjusting a gain of the amplifier such that a summit level of the electric signal can be raised to a predetermined upper limit level. A digitizing device is provided for converting the electric signal amplified by the amplifier into a binary signal, using a predetermined level.

Abstract: In an optical information recording and reproducing apparatus, information is recorded or reproduced by moving a recording medium relative to an optical head. In order to execute information recording onto the medium in the course of the relative movement involving acceleration and deceleration, the generation timing and intensity of a light beam to be generated in correspondence with the information to be recorded are controlled in response to a varying speed of the relative movement so that data pits to be formed in the recording medium can be standardized in pitch and size irrespective of the relative movement speed. Also, in order to permit information reproduction from the medium in the course of the relative movement involving acceleration and deceleration, reproduction timing of data read by the optical head is set in synchronism with variation in the relative movement speed so that the data can be reproduced at proper timing irrespective of the relative movement speed.

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: A system for bar code reading and scanning is provided having automatic gain control for accurate reading of bar codes over a range of distance. An amplifier within the system provides a plurality of selectable amplification gain levels for increasing the size of the signal received by a digitizing element. A processor is programmed to select the gain level. The system has a light source, preferably a laser diode, and a laser diode circuit, which provides accurate setting by the processor of the laser optical power output. The laser diode is calibrated according to each selected gain level of the amplifier such that the system can scan within a desired range of distances from the system to a bar code. The system successively scans a bar code, with each scan being at a different amplification level. In the alternative, a signal size detector provides a signal representative of the size of the signal to the digitizer.

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 optical reading apparatus for reading a two-dimensional symbol includes a housing having an opening portion for confronting the symbol, a gripping portion, and a serial I/F for transmitting a two-dimensional code data corresponding to the two-dimensional symbol to an external apparatus. LEDs mounted near the opening portion generate light to illuminate the two-dimensional symbol. A mirror reflects light reflected from the two-dimensional symbol toward the gripping portion. An automatic diaphragm mechanism regulates the light from the mirror. A two-dimensional type CCD generates electrical signals corresponding to the regulated light. Image processing circuits convert the electrical signals to the two-dimensional code data.

Abstract: An optical reading apparatus (bar code reader) including a plurality of light emitting elements, each light emitting element emitting light in different directions onto an information recording surface which has a linear recording (bar code pattern) printed thereon. A light receiving element receives reflected light from the information recording surface and generates a recording medium read signal which is transmitted to a signal processing section for converting the recording medium read signal into a display signal. The recording medium read signal is also transmitted to a regular reflection detection section. When the regular reflection detection section detects the occurrence of a regular reflection condition from the recording medium read signal, the regular reflection detection section transmits a regular reflection detection signal to a driving controlling section which controls light emission from the plurality of light emitting elements.

Abstract: A system for bar code reading and scanning is provided having automatic gain control for accurate reading of bar codes over a range of distance. An amplifier within the system provides a plurality of selectable amplification gain levels for increasing the size of the signal received by a digitizing element. A processor is programmed to select the gain level. The system has a light source, preferably a laser diode, and a laser diode circuit, which provides accurate setting by the processor of the laser optical power output. The laser diode is calibrated according to each selected gain level of the amplifier such that the system can scan within a desired range of distances from the system to a bar code. The system successively scans a bar code, with each scan being at a different amplification level. In the alternative, a signal size detector provides a signal representative of the size of the signal to the digitizer.

Abstract: A device suitable for a laser-type bar code reader used in a POS (point of sales) system in the distribution industry, and more particularly, to a laser lighting control device in a laser scanner device which reads a bar code using a reflection light of a laser beam. A prolonged operational life and an improved reliability of the laser light source build-in device under intermittent light on/off control is achieved by monitoring its lighting time to execute the operational life control thereof. The laser lighting control device includes a laser light source, a drive unit for performing a light on/off drive of the laser light source to control the light on/off thereof, a control unit for outputting a light on/off command to the drive unit for laser light source control, and a timer unit for measuring the total lighting time of the laser light source.

Abstract: An optical data reading device has a main housing and an optical system housing connected to the main housing. A light source and an imaging optical system are housed in the optical system housing. An image sensor, an image signal processing unit and a light source control unit are housed in the main housing. The light source illuminates a bar code, and the imaging optical system passes light reflected from the bar code into the main housing. The image sensor outputs a signal in accordance with the light passed by the imaging optical system. The image signal processing unit performs a predetermined process on the signal. The light source control unit controls the amount of light generated by the light source in accordance with a processing result obtained by the image signal processing unit.

Abstract: To accurately read optical information more than an opening diameter of a read opening without the read opening contacted with a reading object, in a reader for reading a bar code by irradiating light from a light source to a bar-code label, converging the reflected light through a mirror and a stop by a lens and focusing the converged light on a line image sensor with a shutter, a wavelength detector for detecting a wavelength of the reflected light and a light guide for irradiating light spots indicative of a readable range to the label are provided. Whether a reading state is in a contact reading state in which a read opening contacts the label or in a noncontact reading state in which the read opening separates from the label is determined based on a wavelength of the reflected light detected by the wavelength detector.

Abstract: A barcode scanner, which is particularly suitable for reading barcode information from surfaces having various reflective properties, includes a light intensity control for the light source of the barcode scanner. The light intensity control preferably comprises a means for ramping voltage and a summing circuit which allows the current flowing through the light source to be controlled. In addition, the light intensity control utilizes a clocking means which controls the rate of voltage ramping.

Abstract: An optical reader for optically reading an information pattern representing coded data includes a reading head having a hollow casing with a first opening formed in a wall portion thereof to define a reading area, and a light source to illuminate the reading area. The hollow casing has a second opening formed in another wall portion thereof. The second opening is closed by an optical filter which exhibits a large transmissivity to a part of the light emitted from the light source and included in a predetermined wavelength band. Thus, the reading area is visible through the optical filter and a user can visually confirm whether or not the information pattern to be read is encompassed by the reading area.

Abstract: A contact bar code reader is suitable for reading 2-dimensional bar codes. The reader comprises a housing having therein a source of illumination and optics for producing a diverging beam for illuminating a bar code symbol. A transparent frustoconical guide is removably attached to the housing, and has an conical angle corresponding to the beam's angle of divergence. The guide is dimensioned to encompass the bar code symbol, and its line of contact with the data carrier is substantially fully visible to the operator, who can thus confirm that the guide is in proper operating position relative to the bar code symbol prior to initiating a reading operation. A reading operation can be initiated by pressing on the guide to actuate a switch, or on a manual trigger.

Abstract: An optical information reading apparatus comprises: a semiconductor laser (30); an optical scanning mechanism (50) for scanning bar code (90) using a laser beam emitted from the semiconductor laser (30); a photodetector (70) receiving a returning laser beam reflected at the bar code (90); information reading device (130, 140) for reading out information from the bar code on the basis of the returning laser beam received by the photodetector (70); sweep angle regulating mechanism (150, 180) for restricting a sweep angle of the laser beam used in a scanning operation of the optical scanning device (50) within a predetermined angle so as to scan only one bar code; an operational current detecting circuit (120) for detecting an operational current value of the semiconductor laser (30); and a deterioration judging device for making a judgement as to whether the semiconductor laser (30) is deteriorated or not on the basis of the operational current detected by the operational current value detecting circuit (120).

Abstract: Non-Imaging beam conditioning optical elements are disclosed which allow nearly full power usage from a light source, in a beam scanning information readout device such as a bar code reader. Light which would have been otherwise wasted by using stop apertures as in prior art scanning devices, is utilized efficiently by apportioning a greater amount of the light to the far out targets and less to the close in targets, effectively solving the problem of signal amplitude variation over a long working range. At the same time the novel optical elements provide multiple focal ranges which may be made to overlap thereby providing small beam cross sections for near and distant targets, significantly extending the depth of scanning range over prior art scanners. Amplification and signal processing of received light signals is simplified thereby eliminating the need for complex and fussy AGC amplifiers and limiters to deal with both strong and weak signals from close and distant targets respectively.

Abstract: The optical scanner has an optical scanning head with LED light sources, focusing and receiving optics and a CCD detector array all mounted on a printed circuit board. This assembly, along with a storage buffer and a decoder is contained within a small housing which is attached on its lower side to a semi-glove which the user can wear on the back of his or her hand. The automatic sensing feature of the invention provides hands-free operation by automatically and periodically testing for the presence of a bar code in the scanner's field of view. If the presence of a bar code is detected, the scanner is placed in active mode. When the scanner is not in use, the scanner is powered down to conserve energy.

Abstract: A method and apparatus for calibrating a bar code scanner. The bar code scanner contains circuitry including a programmable read-only memory (PROM) which stores data affecting the operation of other circuitry in the bar code scanner. The operation of the bar code scanner can be optimized by being monitored by an adjustment circuit under the control of a computer, the adjustment circuit producing signals which change the data stored in the PROM. Among the aspects of the bar code scanner which can be affected are optimization of the output signal, optimization of the signal which causes the bar code symbol to be illuminated, and response of the bar code scanner to the lack of a bar code symbol to read.

Abstract: The optical scanning head includes at least one trio of light emitting diodes arranged so the LEDs emit light at different angles to create a fan of light. An optical module includes a light shield or "dark room" and a lens/filter assembly which provides control of the depth of focus of the scanner. The optical module is located behind the light source, and the detector, made up of a CCD array is mounted behind the optic module for detecting the light intensity in the reflected beam over a field of view across a bar code symbol. The CCD array generates an electrical signal indicative of the detected light intensity. A DC source or battery provides DC voltage to the LEDs and CCDs in response to a clocked signal which provides a gradual or sequential illumination of the LEDs and coordinates the activation of the CCDs in order to minimize power consumption during scans.

Abstract: A symbol read device useful as a bar code reader, optical character reader or the like. A symbol bearing surface is illuminated by two different light sources that are distinguishable based on their respective wavelengths or modulated frequencies. A detector detects light reflected from the symbol surface and provides a detection signal indicative thereof. The detection signal is processed to recognize the symbol being read. In a multi-scan embodiment, an automatic gain control (AGC) circuit controls a level of detector signal to aid in recognition of the symbols being read.

Abstract: An optical code reader includes a reading window, a reading control circuit for sensing an image of a 2-dimensional code via the reading window and for converting the sensed image into image data, and a portable frame having an opening used as the reading window, for accommodating the reading control circuit.

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

Abstract: Disclosed is a fully automatic bar code symbol reading system having an hand-supportable laser bar code reading device which can be used in either an automatic hands-on mode of operation, or in an automatic hands-free mode of operation. The system includes a scanner support frame for supporting the hand-supportable device in a user-selected mounting position, and permits complete gripping of its handle portion prior to its use in the hands-on mode of operation. In general, the hand-supportable bar code reading device has long-range and short-range modes of object detection, bar code presence detection and bar code symbol reading. In the illustrative embodiment, the long-range mode is automatically selected when the hand-supportable bar code reading device is placed within the scanner support stand during the automatic hands-free mode of operation.

Abstract: The system has an optical scanning device formed of a plurality of pixel elements for providing a scan output signal representative of a scanned region of an object. The system has a reflector, an illumination source, a light compensator, and an object positioner. The reflector defines an ellipse. The object positioner disposes the object substantially near the major axis of the ellipse. The illumination source emits and applies light energy to the object disposed at a first focus of the ellipse. The light compensator, which varies the light energy emitted from the illumination source, has one or more dedicated pixels of the optical scanning device. The light compensator also has fiber optical transmitters that receive light transmitted from the illumination source and couple to the dedicated pixels, which are unavailable for receiving reflected light from the scanned region of the object.

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

Abstract: In order to prevent a digitizer which receives signals from a bar code reader which scans an inverse code (white bars on black background as opposed to a direct or normal code with black bars on white background) from improperly digitizing a white space as a black bar and also, if desired, to enable the digitizer to operate properly in digitizing signals from direct or inverse codes without switching the digitizer from direct to inverse digitizing mode by operator control, the digitizer is operated, automatically under computer control on different ones of a series of successive scans of the code, which are carried out until the code is successfully read, to provide an output, which is of different states when reading white sections and black sections of the code, and to be restored, respectively, to a state corresponding to the reading of a black section of the code and to a state corresponding to the reading of a white section of the code, when a direct code is to be digitized and when an inverse code is to

Abstract: After serial signals output from a CCD sensor are amplified, a peak value of white levels corresponding to the space portions of bar codes is held by a peak hold circuit, and then the held peak value is converted into a digital value by an analog-to-digital conversion circuit. The value obtained by multiplying accumulation time data from the CCD sensor by the target value of the white level peak value is divided by the digital value. The next accumulation time of the CCD sensor is set on the basis of the result of this division. In this way, the sensitivity of the scanner is adjusted.