Microscan Quadrus Verifier, Руководство пользователя

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Quadrus Verifier User’s Manual
A-25
Appendices
Cell Fill —The percentage of the ideal cell size filled by a directly marked “dot” element.
Check Digit— A Modulus 43 or Modulus 10 digit that is added to the symbol message for
additional data integrity.
CMOS —Complementary Metal Oxide Semiconductor. Like CCDs, CMOS readers include
an array of photo-sensitive diodes, one diode within each pixel. Unlike CCDs, however,
each pixel in a CMOS reader has its own individual amplifier integrated inside.
Connector— A plug or socket on a device or cable to provide in/out connectivity for various
circuits and pins.
Concentrator— Intermediary device that relays data from multiple readers to a host and
that relays commands from the host to the readers or other devices.
Counter— Memory space provided to keep track of reader events.
Daisy Chain— Linkage of master and secondary readers to allow data to be relayed up to
the host via auxiliary port connections.
Data Matrix— A 2D matrix symbology consisting of dark and light square modules, or
elements, within an L-shaped finder pattern.
Decode— A good read. The successful scanning and decoding of the information
encoded in a symbol.
Default— Restores ROM or flash settings, initializes serial commands, and resets all
counters.
Delimited— Bracketed by pre-defined characters.
Decode Rate— The number of good reads per second achieved by the reader.
Dark Field Illumination —Lighting of objects, surfaces, or particles at very shallow or low
angles, so that light does not directly enter the reader’s optics.
Depth of Field —The range of an imaging system as measured by the nearest distance to
the farthest distance that an object in the field of view remains in focus.
Diffused Lighting —Scattered soft lighting from a wide variety of angles used to eliminate
shadows and specular interference from highly reflective surfaces.
Digital-to-Analog Converter (DAC) — A VLSI circuit used to convert digitally-processed
images to analog for display on a monitor.
Digital Imaging —Conversion of a video image to pixels by means of an analog-to-digital
converter, where the level of each pixel can be stored in a host computer.
Digital Signal Processor (DSP)—A VLSI chip designed for ultra-high-speed arithmetic
processing. Often embedded in a vision engine.
Direct Part Mark (DPM)—A machine-readable symbol applied to an individual part using
such techniques as dot peen, laser etch, and chemical etch.
Discrete I/O— Inputs and outputs characterized by discrete signal transitions from one
voltage level to another so that digital switching can occur.
DMA —Direct Memory Access. A capability provided by some computer bus architectures
that allows data to be sent directly to memory from an attached device.
Dot Center Offset —The deviation of the center of a directly marked “dot” element from
the ideal dot center.