Microscan Quadrus Verifier, User Manual

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Quadrus Verifier User’s Manual
Glossary of Terms
Noise —The same as static in a telephone line or “snow” in a television picture, noise is
any unwanted electrical signal that interferes with the image being read and transferred by
the reader.
Normally Closed— A discrete output state that is only active when open.
Normally Open— A discrete output state that is only active when closed.
Output— A channel or communications line. Data or discrete signals that are transmitted
or displayed by a device.
Parity —An error detection routine in which one data bit in each character is set to 1 or 0
so that the total number of bits in the data field is even or odd.
Picket Fence Symbol Orientation —A linear symbol orientation in which the bars are
perpendicular to the symbol’s direction of travel.
Pixel —The basic unit of image composition in a digitized image array.
Pixels Per Element —The number of pixels making up each symbol element.
Port —Logical circuit for data entry and exit. (One or more ports may be included within a
single connector.)
Print Growth —The extent to which dark or light symbol. elements fill their module
boundaries.
Processing Time —The time used by a vision system to receive, analyze and interpret
image information. Often expressed as parts per minute.
Progressive Scan —A non-interlaced scan that doubles the number of visible picture lines
per field by displaying all picture lines at once.
Protocol —The rules for communication between devices, providing a means to control
the orderly flow of information between linked devices.
Quiet Zone —A clear space surrounding a symbol, required for symbol readability.
RAM —Random Access Memory for storage and retrieval of data.
Read Cycle —A pre-defined period of time during which the Verifier will accept symbol
input.
Reference Decode Algorithm— A decoding algorithm that can be found in a specific
symbology specification.
Reference Gray Scale Image— A plot of the reflectance values in x and y coordinates
across a two-dimensional image.
Reflectance Calibration— The process of determining the optimal conditions for symbol
verification in terms of reflected light from the substrate.
Region —An area of an image. Also called a Region of Interest for image processing
operations.
RS-170 —The Electronic Industries Association (EIA) standard governing monochrome
television studio electrical signals. The broadcast standard of 30 complete images per
second.
Saturation —The degree to which a color is free of white. One of the three properties of
color perception along with hue and intensity.
Scattering —Redirection of light reflecting off a surface or through an object.