Microscan Quadrus MINI Imager, Руководство пользователя

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Quadrus MINI Imager User’s Manual
Glossary of Terms
Half Duplex
— A communications system in which signals can travel between devices in
both directions, but not simultaneously.
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 and discrete signals.
Image
— Projection of an object or scene onto a plane (i.e. screen or image sensor).
Image Processing (IP)
— Transformation of an input image into an output image with
desired properties.
Image Resolution
— The number of rows and columns of pixels in an image. A higher
resolution means that more pixels are available per element of the symbol being read.
Examples: 640 x 480 (VGA); 854 x 480 (WVGA); 1280 x 1024 (SXGA); 2048 x 1536
(QXGA).
Image Sensor
— A device that converts a visual image to an electrical signal; a
CCD
or
CMOS
array.
Initialize
— Implement serial configuration commands into the imager’s active memory.
Input
— A channel or communications line. Decoded data or a discrete signal that is
received by a device.
Integration
— Exposure of pixels on a
CMOS
sensor.
IP
— See
Image Processing
.
Ladder Orientation
— A linear symbol orientation in which the bars are parallel to the
symbol’s direction of travel.
LED
— See
Light-Emitting Diode
.
Light-Emitting Diode (LED)
— A semiconductor device that emits light when conducting
current.
Lens
— A transparent piece of material with curved surfaces which either converge or
diverge light rays.
Machine Vision
— The automatic acquisition and analysis of images to obtain desired
data for controlling a specific activity.
Multidrop
— A communications protocol for networking two or more imagers or other
devices with a concentrator (or controller) and characterized by the use of individual
device addresses and the RS-485 standard.
Noise
— The same as static in a phone line or “snow” in a television picture, noise is any
unwanted electrical signal that interferes with the image being read and transferred by the
imager.
Normally Closed
— A discrete output state that is only active when open.
Normally Open
— A discrete output state that is only active when closed.
Object Plane
— An imaginary plane in the field of view, focused by an imager’s optical
system at the corresponding image plane on the sensor.