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.
摘要:
A hand-supportable automatic digital imaging-based bar code symbol reading device comprises: an automatic object presence detection subsystem; an area-type image formation and detection subsystem having a narrow-area image-capture mode of operation; a LED-based illumination subsystem having narrow-area illumination mode of operation; an image capturing and buffering subsystem; and an image-processing bar code symbol reading subsystem. The automatic object presence detection subsystem automatically detects an object, and the LED-based illumination subsystem automatically illuminates the detected object in a field of narrow-area narrow-band illumination, while the area-type image formation and detection subsystem captures a narrow-area image thereof. The image-processing bar code symbol reading subsystem automatically and directly applies decode image processing operations on the captured image, in an outwardly-directed manner, referenced from the center of the captured narrow-area image, to automatically read a 1D bar code symbol on the detected object.
摘要:
Method of performing autodiscrimination of 1D/2D bar code symbologies in a semi-automatic hand-supportable imaging-based bar code symbol reader having narrow-area and wide-area image capture modes of operation. The hand-supportable digital imaging-based bar code symbol reading device comprises: 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-activatable trigger switch; and a system control subsystem integrated with each of the above-described subsystems.
摘要:
A method of reading bar code symbols comprising the steps of: (a) projecting an image cropping zone (ICZ) framing pattern within the FOV of an image sensing array during wide-area illumination and image capturing operation; (b) visually aligning an object to be imaged within the ICZ framing pattern; (c) forming and capturing an wide-area image of the entire FOV, which spatially encompasses the ICZ framing pattern aligned about the object to be imaged; (d) using automatic software-based image cropping algorithm to automatically crop the pixels within the spatial boundaries defined by the ICZ framing pattern, from those pixels contained in the entire wide-area image frame captured during step (c); and (e) automatically decode processing the image represented by the cropped image pixels in the ICZ framing pattern so as to read a 1D or 2D bar code symbol graphically represented therein.
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 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. Only when all sensor elements in the image-sensing sensing array are activated and in state of integration, then narrow-band illumination is produced for illuminating objects in FOV of the system and simultaneously detected by a photo-detector for measuring light exposure within the FOV, and also by an area-type image sensing array for detecting a digital image of said illuminated object.
摘要:
A method of reading bar code symbols using a digital-imaging based code symbol reading system employing an event-driven multi-tier modular software architecture and supporting automatic operating system login and loading of a bar code symbol reading application.
摘要:
A method of reading bar code symbols comprising the steps of: (a) projecting an image cropping zone (ICZ) framing pattern within the FOV of an image sensing array during wide-area illumination and image capturing operation; (b) visually aligning an object to be imaged within the ICZ framing pattern; (c) forming and capturing an wide-area image of the entire FOV, which spatially encompasses the ICZ framing pattern aligned about the object to be imaged; (d) using automatic software-based image cropping algorithm to automatically crop the pixels within the spatial boundaries defined by the ICZ framing pattern, from those pixels contained in the entire wide-area image frame captured during step (c); and (e) automatically decode processing the image represented by the cropped image pixels in the ICZ framing pattern so as to read a 1D or 2D bar code symbol graphically represented therein.
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.