摘要:
A hand-supportable digital imaging-based bar code symbol reading system comprises: an automatic object presence detection subsystem; an image formation and detection subsystem employing a CMOS area-type image detection array; an LED-based illumination subsystem employing a LED illumination array for generating a field of narrow-band LED illumination; an automatic light exposure measurement and illumination control subsystem employing LED illumination driver circuitry; an image capturing and buffering subsystem; an image-processing bar code symbol reading subsystem; an input/output subsystem; a narrow-band transmission-type optical filter subsystem; and a system control subsystem for controlling the subsystems. The time duration that the CMOS area-type image sensing array is exposed to narrow-band illumination, from the LED-based illumination array, is managed by controlling the time that the LED-based illumination array generates narrow-band illumination in response to first and second control activation signals generated by the CMOS image sensing array and the automatic object presence detection subsystem, respectively, aboard the system.
摘要:
A portable digital image capturing and processing system comprising: an image formation and detection subsystem; a narrow-band illumination subsystem; a narrow-band transmission-type optical filter subsystem; an automatic light exposure measurement subsystem; and an automatic illumination control subsystem. The image formation and detection subsystem has an area-type image sensing array for detecting digital images of objects formed thereon by image formation optics providing a field of view (FOV) for the system. Within the FOV of the image formation and detection subsystem, the narrow-band illumination subsystem produces a field of narrow-band illumination consisting essentially of a narrow band of wavelengths of visible illumination. The narrow-band transmission-type optical filter subsystem transmits substantially only the narrow band of wavelengths of visible illumination produced from the narrow-band illumination subsystem, and rejects all other optical wavelengths outside the narrow band however generated by ambient illumination sources. The automatic light exposure measurement subsystem employs a photo-detector operated independently from the area-type image sensing array, for automatically measuring the light exposure incident upon a selected portion of the FOV, and producing an electrical signal representative of the light exposure measurement. The automatic illumination control subsystem responds to the electrical signal and controls the duration of narrow-band illumination produced from the narrow-band illumination subsystem.
摘要:
A hand-supportable digital image capture and processing system comprises: an area-type image formation and detection subsystem having an area-type image detection array; an LED-based illumination subsystem having a LED-based illumination array; an automatic light exposure measurement and illumination control subsystem; an image capturing and buffering subsystem; and an image-processing subsystem. The LED array is automatically driven in a precise manner to globally expose the area-type image detection array with LED-based illumination only when substantially all of its rows of pixels are in a state of integration and have a common integration time, thereby enabling the capture of high quality images independent of the relative motion between the object and the hand-supportable digital image capture and processing system.
摘要:
A hand-supportable digital imaging-based bar code symbol reading device comprises: an automatic object presence detection subsystem; a multi-mode area-type image formation and detection subsystem having a field of view (FOV), and narrow-area and wide area image capture modes of operation; a multi-mode LED-based illumination subsystem having narrow-area and wide area illumination modes of operation; an automatic light exposure measurement and illumination control subsystem; an image capturing and buffering subsystem; an image-processing bar code symbol reading subsystem; an input/output subsystem; and a system control subsystem. In the digital imaging-based bar code reading device of the present invention, the automatic illumination and exposure control subsystem continuously measures the light exposure incident upon a central portion of the FOV, and automatically controls the operation of the LED-based multi-mode illumination subsystem so that the detected object is sufficiently illuminated and the multi-mode image formation and detection subsystem enabled to form and detect good quality digital images of the automatically detected object during illumination and imaging operations.
摘要:
Method of and apparatus for processing captured images within a semi-automatic hand-supportable imaging-based bar code symbol reader in order to read 1D and/or 2D bar code symbols graphically represented therein. The semi-automatic hand-supportable digital imaging-based bar code symbol reader comprises: an automatic object presence detection subsystem; a multi-mode area-type image formation and detection subsystem having narrow-area and wide area image capture modes of operation; a multi-mode LED-based illumination subsystem having narrow-area and wide area illumination modes of operation; an image capturing and buffering subsystem; a multi-mode image-processing bar code symbol reading subsystem; an input/output subsystem; a manually-activatable trigger switch; and a system control subsystem integrated with each of the above-described subsystems. The bar code symbol reader embodies advanced image processing methods for reading 1D and/or 2D bar code symbols graphically represented in captured digital images.
摘要:
A hand-supportable digital imaging-based bar code symbol reading system comprises: an automatic object presence detection subsystem; an image formation and detection subsystem employing a CMOS area-type image detection array; an LED-based illumination subsystem employing a LED illumination array for generating a field of narrow-band LED illumination; an automatic light exposure measurement and illumination control subsystem employing LED illumination driver circuitry; an image capturing and buffering subsystem; an image-processing bar code symbol reading subsystem; an input/output subsystem; a narrow-band transmission-type optical filter subsystem; and a system control subsystem for controlling the subsystems. The time duration that the CMOS area-type image sensing array is exposed to narrow-band illumination, from the LED-based illumination array, is managed by controlling the time that the LED-based illumination array generates narrow-band illumination in response to first and second control activation signals generated by the CMOS image sensing array and the automatic object presence detection subsystem, respectively, aboard the system
摘要:
A wireless hand-supportable digital imaging-based bar code symbol reading device comprising: an automatic object presence and range detection subsystem; a multi-mode image formation and detection subsystem having narrow-area and wide area image capture modes of operation; a multi-mode LED-based illumination subsystem having narrow-area and wide area illumination modes of operation; an automatic light exposure measurement and illumination control subsystem; an image capturing and buffering subsystem; a multi-mode image-processing bar code symbol reading subsystem; an input/output subsystem; a manually-actuatable trigger switch; and a system control subsystem for controlling these subsystems.
摘要:
A method of determining the lower limit of decoding resolution in a digital imaging-based bar code symbol reader. A software-based optical design program is used to generate the composite DOF chart of image formation optics employed in the digital imaging-based bar code symbol reader. The modulation transfer function (MTF) of the object image is used to determine the smallest mil size code that can be decoded, at a given object distance, to produce an optical performance curve. The program calculates the size of the field of view (FOV) of a single sensor pixel, when projected through the image formation optics and out into object space. For both the 1.4 and 1.6 sampling limit pixel rules, the calculated FOV values are plotted on the same axes as the optical performance curve. Using graphical solution techniques, the sampling limit line of choice determines the lower limit of the decoding resolution in the imaging-based bar code symbol reader.
摘要:
A hand-supportable digital imaging-based bar code symbol reading device comprises: a image formation and detection subsystem; a LED-based illumination subsystem; an automatic light exposure measurement and illumination control subsystem; an image capturing and buffering subsystem; an image-processing bar code symbol reading subsystem; an input/output subsystem; and a system control subsystem for controlling the subsystems. During each image capture cycle, a single frame of pixel data is automatically detected by the CMOS area-type image sensing array when substantially all rows of pixels therein are in a state of integration and have a common integration time, and then the single frame of pixel data is transmitted from the CMOS area-type image sensing array into a FIFO buffer, and then mapped into memory, for subsequent image processing.
摘要:
A hand-supportable digital imaging-based bar code symbol reading device comprises: an automatic object presence and range detection subsystem; an area-type image formation and detection subsystem having a CMOS area-type image detection array, and narrow-area and wide area image capture modes of operation; an LED-based illumination subsystem having LED arrays, and narrow-area and wide area illumination modes of operation; an automatic light exposure measurement and illumination control subsystem; an image capturing and buffering subsystem; and an image-processing bar code symbol reading subsystem. The LED arrays associated with the LED-based illumination subsystem are automatically driven in a precise manner to globally expose the CMOS area-type image detection array with LED-based illumination only when substantially all of its rows of pixels are in a state of integration and have a common integration time, thereby enabling the image capturing and buffering subsystem to capture high quality images independent of the relative motion between the hand-supportable digital imaging-based bar code symbol reading device and the object.