Microscan Quadrus Verifier, User Manual

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Quadrus Verifier User’s Manual
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Appendices
Gradient —The rate of change of pixel intensity (first derivative).
Gray Scale —Variations of values from white, through shades of gray, to black in a digitized
image with black assigned the value of zero and white the value of one.
Grid Non-Uniformity— A measurement of the largest vector deviation of a 2D symbol’s
grid intersections.
Half Duplex— A configuration in which auxiliary port data is sent directly to the host and
displayed on the auxiliary port screen.
Histogram —A graphical representation of the frequency of occurrence of each intensity or
range of intensities (gray levels) of pixels in an image. The height represents the number of
observations occurring in each interval.
Host— A computer, PLC, or other device that is used to execute commands and process
data.
IEC (International Electrotechnical Commission)—A global organization that publishes
international standards for electrical, electronic, and other technologies.
Image —Projection of an object or captured area onto a plane (i.e. screen or image sensor).
Image Processing —Transformation of captured image data into an output image with
desired properties.
Image Resolution —The number of rows and columns of pixels in an image. An image
sensor’s total number of pixels.
Image Sensor— Array of pixels on a CCD or CMOS sensor.
Initialize— To implement serial configuration commands into the Verifier’s active memory.
Input— A channel or communications line. Data or a discrete signal received by a device.
See also Output .
Integration— Exposure of pixels on a CCD or CMOS sensor.
ISO (International Organization for Standardization)—A network of the national standards
institutes of more than 155 countries, with a central headquarters in Geneva, Switzerland.
IUID (Item Unique Identification)—A United States Department of Defense initiative to
implement a globally accepted identification system based on globally unique and
unambiguous identifiers.
Ladder Orientation— A linear symbol in which the bars are parallel to the symbol’s
direction of travel (assuming horizontal movement).
LED —Light emitting diode. Often used as a strobe for objects traveling at medium speed.
Lens —A transparent piece of material with curved surfaces which cause light rays to
converge or to diverge.
Machine Vision —The automatic acquisition and analysis of images to obtain desired data
for the control of a specific application.
Modulation —A measurement of the uniformity of light and dark elements within a symbol.
Multidrop— A communications protocol for networking two or more readers or other
devices with a concentrator (or controller), and characterized by the use of individual
device addresses and the RS-485 standard.