摘要:
A coplanar laser illumination and imaging subsystem deployable in an image capturing and processing system, and including an image formation and detection (IFD) subsystem having an image sensing array and optics providing a field of view (FOV) on the image sensing array, and forming an image of an object within the FOV and detecting said image on the image sensing array and producing a digital image thereof. The system includes a spectral-mixing based illumination subsystem having an array of VLDs for producing a visible illumination beam, and an array of IR laser diodes (LDs) for producing an invisible illumination beam. The visible and invisible illumination beams spatially overlaps and spatially/temporally intermixes with each other to produce a composite spectrally-mixed illumination beam having a relative power ratio (VIS/IR), and is substantially coplanar with the FOV of said image sensing array. A laser despeckling mechanism is provided for reducing the coherence of the composite spectrally-mixed illumination beam, and/or its components, so that the digital images produced by the IFD subsystem having substantially reduced levels of speckle-pattern noise when the laser despeckling mechanism is operational.
摘要:
A laser illumination beam generation system including a laser diode (LD) for producing a laser beam in response to a diode current supplied thereto, wherein the laser beam has a central characteristic wavelength. Diode current drive circuitry generates the diode current and supplies the same to the VLD. A high frequency modulation (HFM) circuitry modulates the diode current supplied to the laser diode, so as to produce a spectral side-band components about the central characteristic wavelength, and thereby reduces the coherence of the laser illumination beam as well as its coherence length. An optical multiplexing (OMUX) device receives the laser beam as an input beam and generates multiple laser beams therefrom and recombines the multiple laser beams so as to produce a composite output laser illumination beam having reduce coherence.
摘要:
A method of driving a plurality of visible and invisible laser diodes so as to produce an illumination beam having a dynamically managed ratio of visible to invisible (IR) spectral energy/power during object illumination and imaging operations. The method involves supplying a plurality of visible laser and invisible laser diodes with a predetermined/default values of diode drive currents so as to illuminate the object with a spectral mixture of illumination during object illumination and imaging operations. One or more digital images of the illuminated object are captured and the image contrast quality thereof is measured, in real-time, so as to generate feedback or control data. This feedback or control data is used to dynamically generate the necessary values for the adjusted diode drive currents that are used to drive the visible and invisible laser diodes and produce an illumination beam having a dynamically managed ratio of visible to invisible (IR) spectral energy/power required to produce images of sufficient image contrast to ensure satisfactory image processing, while minimizing visual brightness to humans, at a POS station during object illumination and imaging operations.
摘要:
A digital image capturing and processing system for illuminating objects using automatic object detection and spectral-mixing illumination technique. The system comprises an area-type illumination and imaging module for projecting a coextensive area-type illumination and imaging field (i.e. zone) into a 3D imaging volume during object illumination and imaging operations. The area-type illumination and imaging module includes a spectral-mixing based illumination subsystem for producing a first field of visible illumination from an array of visible LEDs, and producing a second field of invisible illumination from an array of infrared (IR) LEDs, wherein the first and second fields of illumination spatially overlap and intermix with each other and produce a composite illumination field that is at least substantially coextensive with the FOV of the image sensing array. An automatic object detection subsystem automatically detects an object moving through the 3D imaging volume, while an illumination control subsystem controls the relative power ratio (VIS/IR) of visible illumination and invisible illumination during system operations so as to achieve sufficient image contrast in captured digital images to ensure satisfactory image processing.
摘要:
Digital image capture and processing systems and methods for generating and projecting coplanar illumination and imaging planes and/or coextensive area-type illumination and imaging zones, through one or more imaging windows, and into a 3D imaging volume in a retail POS environments, while employing automatic object motion and/or velocity detection, real-time image analysis and other techniques to capture and processing high-quality digital images of objects passing through the 3D imaging volume, and intelligently controlling and/or managing the use of visible and invisible forms of illumination, during object illumination and imaging operations, that might otherwise annoy or disturb human operators and/or customers working and/or shopping in such retail environments.
摘要:
A method of illuminating objects using adaptively controlled mixing of spectral illumination energy to form and detect digital images of objects at POS environments with sufficiently high image contrast and quality. The method comprises providing, at a POS environment, a digital image capture and processing system having a system housing with an imaging window, and a coplanar illumination and imaging station disposed within said system housing, for projecting a coplanar illumination and imaging plane through the imaging window into an imaging volume during object illumination and imaging operations. As the object is moved through the imaging volume, its motion is automatically detected, and signals indicative of said detected object are generated. In response to the generated signals, a first field of visible illumination is produced from an array of visible laser diodes (VLDs), simultaneously with a second field of invisible illumination from a array of infrared (IR) laser diodes (LDs). These first and second fields of illumination spatially overlap and intermix with each other and produce a composite planar illumination beam that is substantially coextensive with the FOV. During object illumination and imaging operations, the relative power ratio (VIS/IR) of these fields of visible illumination and invisible illumination are controlled as one or more linear digital images of the illuminated object are formed and detected, captured and buffered, and ultimately processed so as to read one or more 1D and/or 2D code symbols graphically represented in the digital images. In an illustrative embodiment, during object illumination and imaging operations operation, the relative power ratio (VIS/IR) is adaptively controlled to form and detect digital images of objects at POS environments with sufficiently high image contrast and quality.
摘要:
A multi-stage laser beam despeckling device including a first laser beam despeckling module for optically multiplexing an input laser beam into a temporal/spatial coherence-reduced output laser beam; and a second laser beam despeckling module, optically coupled to the first laser beam despeckling module, for receiving the temporal/spatial coherence-reduced as an input laser beam to the second despeckling module and producing a further temporal/spatial coherence-reduced output laser beam.
摘要:
A digital image capturing and processing system including a system housing having an imaging window; illumination and imaging stations for generating and projecting illumination and imaging planes or zones through the imaging window, and into a 3D imaging volume definable relative to the imaging window, for digital imaging an object passing through the 3D imaging volume, and generating digital linear images of the object as the object intersects the illumination and imaging planes or zones during system operation. A digital image processor processes the digital images and automatically recognizes graphical intelligence (e.g. bar code symbols, alphanumeric characters etc) graphically represented in the digital images.
摘要:
A POS-based digital image capturing and processing system for illuminating objects using automatic object detection and spectral-mixing illumination technique. The system comprises an area-type illumination and imaging station for projecting a coextensive area-type illumination and imaging field (i.e. zone) into a 3D imaging volume during object illumination and imaging operations. The area-type illumination and imaging station includes an illumination subsystem for producing a first field of visible illumination from an array of visible LEDs, and producing a second field of invisible illumination from an array of infrared (IR) LEDs. wherein the first and second fields of illumination spatially overlap and intermix with each other and are substantially coextensive with the FOV of the image sensing array. An automatic object motion detection subsystem automatically detects the motion of an object moving through the 3D imaging volume, while an illumination control subsystem controls the relative power ratio (VIS/IR) of visible illumination and invisible illumination during system operation so as to minimize the amount of visible illumination energy required to capture sufficiently high-contrast images of said objects and successfully process the same.
摘要:
A laser beam despeckling device including a laser diode for producing a laser beam having a central characteristic wavelength. The device includes diode current drive circuitry for producing a diode drive current to drive said laser diode and produce said laser beam. High frequency modulation (HFM) circuitry modulates the diode drive current at a sufficiently high frequency to cause said laser diode to produce spectral side-band components about the central characteristic wavelength, and reducing the coherence as well as coherence length of the laser beam. An optical beam multiplexing (OMUX) module is provided for receiving the laser beam as input beam, a generating as output, a plurality of laser beam components that are recombined to produce a composite laser beam having substantially reduced coherence for use in illumination applications where a substantial reduction in speckle pattern noise is achieved.