Patents by Inventor Yajun Li

Yajun Li has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 5859418
    Abstract: An optical funnel evenly distributes light from an array of LEDs to a bar code. A support member with a central aperture holds the LEDs. A shroud with an angled reflective interior surface spreads the light from the LEDs to the bar code. The funnel also optically isolates the LEDs from the photodector in the scanner.
    Type: Grant
    Filed: January 25, 1996
    Date of Patent: January 12, 1999
    Assignee: Symbol Technologies, Inc.
    Inventors: Yajun Li, Joseph Katz
  • Patent number: 5821522
    Abstract: A bar code scanner comprises a lens structure for effecting magnification of a bar code image along an optical axis of the scanner. A support member supports the lens structure, the support member being movable into first and second bi-stable positions along the optical axis and disposing the lens structure in respective first and second locations spaced mutually along the optical axis, and a displacing unit for displacing the support member exclusively into residence in one or the other of the first and second positions.
    Type: Grant
    Filed: April 3, 1996
    Date of Patent: October 13, 1998
    Assignee: Symbol Technologies, Inc.
    Inventors: Yajun Li, Eugene Joseph
  • Patent number: 5821521
    Abstract: Optical scanning is established by superimposing the alternating magnetic field of a coil magnet with the permanent field set up by a permanent magnet which surrounds the coil magnet. Both magnets are fixedly secured to a support at one axial end of the magnets and a flexible diaphragm is secured to the other axial end of the permanent magnet. A scanning mirror is effectively attached between the support and the diaphragm. When the coil magnet is activated, the diaphragm is rapidly flexed which causes the movement of the scanning mirror.
    Type: Grant
    Filed: September 19, 1997
    Date of Patent: October 13, 1998
    Assignee: Symbol Technologies, Inc.
    Inventors: Raj Bridgelall, Joseph Katz, David P. Goren, Paul Dvorkis, Yajun Li
  • Patent number: 5811773
    Abstract: To reduce the size and weight of an optical scanner, the present invention provides a mirrorless beam scanning unit. A flexible member, such as a multi-wire, flat, electrical cable is connected to the light emitter. Reciprocation of the light emitter during emission of light by the light emitter causes the light to scan a surface, such as a surface bearing a bar code label. The cable flexes during such reciprocation.
    Type: Grant
    Filed: February 14, 1997
    Date of Patent: September 22, 1998
    Assignee: Symbol Technologies, Inc.
    Inventors: Simon Bard, Yajun Li, Jerome Swartz, Boris Metlitsky, Joseph Katz, Askold Strat, Harold Charych
  • Patent number: 5798515
    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.
    Type: Grant
    Filed: April 3, 1996
    Date of Patent: August 25, 1998
    Assignee: Symbol Technologies, Inc.
    Inventors: Yajun Li, Edward Barkan
  • Patent number: 5744790
    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.
    Type: Grant
    Filed: January 25, 1996
    Date of Patent: April 28, 1998
    Assignee: Symbol Technologies, Inc.
    Inventor: Yajun Li
  • Patent number: 5717221
    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.
    Type: Grant
    Filed: October 11, 1996
    Date of Patent: February 10, 1998
    Assignee: Symbol Technologies, Inc.
    Inventors: Yajun Li, Robert A. Doran, John Barile
  • Patent number: 5710417
    Abstract: A plurality of the areas of differing light reflectivity of a bar code symbol or the like are simultaneously illuminated using, for example, a beam of light that has an elongate cross-section. The light beam is swept over the symbol to be read in a direction transverse to the elongated dimension of the illuminated region so that a two-dimensional area of the symbol is illuminated over time. The reflected light is sensed by a 1D CCD array. A microprocessor within the scanner provides visual feedback to aid a user in aligning the device, and also provides for a selectable aspect ratio for the image, a selectable image resolution and size, a selectable aspect ratio of the illumination, and a selectable pixel size. All of these options may be programmed within the microprocessor, enabling the device to read a large variety of two-dimensional symbols.
    Type: Grant
    Filed: June 2, 1995
    Date of Patent: January 20, 1998
    Assignee: Symbol Technologies, Inc.
    Inventors: Eugene Joseph, Yajun Li, Duanfeng He, Joseph Katz, Jerome Swartz
  • Patent number: 5708262
    Abstract: A miniature high speed bar code scanning element is detachably mounted within an industry standard PCMCIA card for implementation in personal computing devices.
    Type: Grant
    Filed: June 20, 1996
    Date of Patent: January 13, 1998
    Assignee: Symbol Technologies, Inc.
    Inventors: Ron Goldman, Edward R. Alexander, Yajun Li, Simon Bard, Askold Strat, Joseph Katz, Boris Metlitsky
  • Patent number: 5705799
    Abstract: An optical scanning assembly turns an optical element in opposite circumferential directions about a longitudinal axis along which a light beam from a light source is emitted. The optical element and the light source are mounted on individual supports between which torsion elements are connected. An electrical coil arrangement interacts with a permanent magnet to effect the turning movement.
    Type: Grant
    Filed: April 3, 1996
    Date of Patent: January 6, 1998
    Assignee: Symbol Technologies, Inc.
    Inventor: Yajun Li
  • Patent number: 5672858
    Abstract: A scanning device for reading indicia of differing light reflectivity, including bar code or matrix array symbols, has a single light emitter, such as a laser or light emitting diode, for generating a scanning light beam to visually illuminate sequential portions of the indicia. A sensor, such as a charge coupled or other solid state imaging device, simultaneously detects light reflected from portions of the indicia and generates an electrical signal representative of the spacial intensity variations the portions of the indicia. The scanning device may also include an ambient light sensor, and a second light emitter for use only in aiming or orienting the scanning device. A photodetector may also be provided to separately detect one symbol virtually simultaneous with the detection of another symbol by the sensor or to provide dual modalities. A method for reading indicia is also provided.
    Type: Grant
    Filed: June 30, 1994
    Date of Patent: September 30, 1997
    Assignee: Symbol Technologies Inc.
    Inventors: Yajun Li, Joseph Katz, Jerome Swartz, Daniel McGlynn
  • Patent number: 5661290
    Abstract: To reduce the size and weight of an optical scanner, the present invention provides a mirrorless beam scanning unit. A flexible support structure, such as one or more strips of mylar, movably mounts the light emitter in response to a motive force, for example as might be applied by a combination of a permanent magnet coupled to the light emitter and a fixedly mounted electromagnet driven by an alternating current signal. Reciprocation of the light emitter during emission of light by the light emitter causes the light to scan a surface, such as a surface beating a bar code label.
    Type: Grant
    Filed: February 7, 1996
    Date of Patent: August 26, 1997
    Assignee: Symbol Technologies, Inc.
    Inventors: Simon Bard, Yajun Li, Jerome Swartz, Boris Metlitsky, Joseph Katz, Askold Strat, Harold Charych
  • Patent number: 5637856
    Abstract: Optical scanning of one- and two-dimensional barcode symbols is carried out first in an aim mode wherein the symbol is scanned using a first scan pattern that is relatively small and dense so as to be visible to the user and thereafter using a second, larger and more robust scan pattern for decoding. During aiming, the symbol is partially decoded to determine type and orientation, and this information is applied to control the angle of the scan pattern produced, the rate at which the scan pattern is increased for optimum decoding, and the ultimate pattern size. Preferred scan patterns, as well as unique scan mechanisms, are described.
    Type: Grant
    Filed: September 25, 1995
    Date of Patent: June 10, 1997
    Assignee: Symbol Technologies, Inc.
    Inventors: Raj Bridgelall, Joseph Katz, David P. Goren, Paul Dvorkis, Yajun Li
  • Patent number: 5621203
    Abstract: A plurality of the areas of different light reflectivity of a bar code symbol, or the like, are simultaneously illuminated, using, e.g., a beam of laser light that has an elongated cross-section. The laser light beam is swept over the symbol in a direction transverse to the elongated dimension of the illuminated region so that a two-dimensional area of the symbol is illuminated over time, until the symbol is read. The light that reflects from the illuminated region of the symbol is imaged on a linear sensor array, which is then scanned or read out to produce signals representative of spatial intensity variations of the imaged light along a linear path in the field of view.
    Type: Grant
    Filed: June 30, 1994
    Date of Patent: April 15, 1997
    Assignee: Symbol Technologies
    Inventors: Jerome Swartz, Yajun Li, Paul Dvorkis, Glenn Spitz
  • Patent number: 5536925
    Abstract: An optical reading system for reading optically encoded information represented by a symbol on a target includes a rotational shaft, a light emitter for producing a beam of light to scan a path through a scan field, and a light detector for detecting light reflected from the symbol to read the optically encoded information. A means for oscillating the light emitter and light detector about a longitudinal axis of the rotational shaft is also provided. At least one electrical conductor is connected to each of the light emitter and light detector for providing electrical energy thereto. Each electrical conductor is affixed between distal ends thereof at a point coincident with a point on the longitudinal axis of the rotational shaft.
    Type: Grant
    Filed: March 28, 1994
    Date of Patent: July 16, 1996
    Assignee: Symbol Technologies, Inc.
    Inventors: Simon Bard, Yajun Li, Jerome Swartz, Boris Metlitsky, Joseph Katz, Askold Strat, Hal Charych
  • Patent number: 5521367
    Abstract: The laser diode of an optical scanning system is located in a separate unit and light therefrom carried to a remote scan head via an optical fiber. This reduces the size and weight of the scan head and reduces the temperature sensitivity of the scan head. The scan head may include an optical sensor for detecting light reflected from scanned symbols. Alternatively, the separate unit may house the sensor, and the same fiber or an additional fiber will collect the reflected light and transmit that light back to the sensor. The invention also encompasses a number of electromagnetic and piezoelectric systems for producing a scanning motion of the beam emitted by the scan head.
    Type: Grant
    Filed: August 3, 1994
    Date of Patent: May 28, 1996
    Assignee: Symbol Technologies, Inc.
    Inventors: Simon Bard, Joseph Katz, Miklos Stern, Yajun Li
  • Patent number: 5506392
    Abstract: A bar code reader capable of working over a wider range of working angle and for a wider range of bar code densities, using improved optics and sensing elements. The optics and sensing elements and/or the associated circuitry are arranged to provide two channels of data derived from the scanned bar code. The two channels have differing resolutions. Analysis of the data from the two channels provides a single decoded result. As the working angle and density vary at least one of the resolutions will be appropriate for sensing all or most of the bar coded data. The data from the channel producing a valid result can be used, or if neither channel produces a valid result by itself, data from each channel can be analyzed and valid portions of the data from both channels combined to produce the single decoded result. The different resolution of the two channels can be provided using different size photodetection areas, e.g., small and large groups of active areas on a sensor array.
    Type: Grant
    Filed: September 28, 1994
    Date of Patent: April 9, 1996
    Assignee: Symbol Technologies, Inc.
    Inventors: Edward Barkan, David P. Goren, Joseph Katz, Yajun Li, Jerome Swartz, Thomas Mazz
  • Patent number: 5504316
    Abstract: Optical scanning of one- and two-dimensional barcode symbols is carried out first in an aim mode wherein the symbol is scanned using a first scan pattern that is relatively small and dense so as to be visible to the user and thereafter using a second, larger and more robust scan pattern for decoding. During aiming, the symbol is partially decoded to determine type and orientation, and this information is applied to control the angle of the scan pattern produced, the rate at which the scan pattern is increased for optimum decoding, and the ultimate pattern size. Preferred scan patterns, as well as unique scan mechanisms, are described.
    Type: Grant
    Filed: November 17, 1993
    Date of Patent: April 2, 1996
    Assignee: Symbol Technologies, Inc.
    Inventors: Raj Bridgelall, Joseph Katz, David P. Goren, Paul Dvorkis, Yajun Li
  • Patent number: 5468952
    Abstract: A miniature high speed bar code scanning element is housed within an industry standard PCMCIA card for implementation in personal computing devices. In one embodiment, the scan element is mounted on the exterior of the card for pivotal movement about vertical and horizontal axes.
    Type: Grant
    Filed: June 20, 1994
    Date of Patent: November 21, 1995
    Assignee: Symbol Technologies, Inc.
    Inventors: Edward R. Alexander, Ron Goldman, Yajun Li, Simon Bard, Askold Strat, Joseph Katz, Boris Metlitsky
  • Patent number: 5404001
    Abstract: The laser diode of an optical scanning system is located in a separate unit and light therefrom carried to a remote scan head via an optical fiber. This reduces the size and weight as well as temperature sensitivity of the scan head. The separate unit may include an optical sensor for detecting light reflected from scanned symbols. If the separate unit houses the sensor, the same fiber or an additional fiber will collect the reflected light and transmit that light back to the sensor. An electromagnetic system produces a scanning motion of the beam emitted by the scan head where the optical fiber is attached to a magnet.
    Type: Grant
    Filed: October 8, 1992
    Date of Patent: April 4, 1995
    Inventors: Simon Bard, Joseph Katz, Miklos Stern, Yajun Li