Omron V440-F, Руководство пользователя

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Appendices
S-2 V440-F C-Mount Code Reader User Manual
S-1 Glossary of Terms
Aberration — The failure of an optical lens to produce an exact point-to-point correspondence
between the object and its resulting image. Various types are chromatic, spherical, coma, astigmatism,
and distortion.
Absorption — The loss of light of certain wavelengths as it passes through a material and is converted
to heat or other forms of energy.
Active Illumination — Lighting an area with a light source coordinated with the acquisition of an
image. Strobed flash tubes and pulsed lasers are examples.
Ambient Light — Light which is present in the environment of the imaging front end of a vision system
and generated from outside sources. This light, unless used for actual illumination, will be treated as
background
Noise by the vision system.
Analog — A smooth, continuous voltage or current signal or function whose magnitude (value) is the information.
Analog-to-Digital Converter (A/D Converter or ADC) — A device that converts an analog voltage or
current signal to a discrete series of digitally encoded numbers (signal) for computer processing.
Application-Specific Integrated Circuit (ASIC) — An integrated circuit that is customized for a
particular kind of use, rather than general use. All vision system elements including firmware can be
integrated into one ASIC.
Architecture — The hardware organization of a vision system designed for high speed image analysis.
Aspect Ratio — The ratio between the height and width of a sensor or display. Found by dividing the
vertical number of pixels (height) by the horizontal number of pixels (width) leaving it in fractional format.
Automatic Gain Control (AGC) — Adjustment to signal strength that seeks to maintain a constant
level regardless of the distance between a reader and symbol.
Auxiliary Port — RS-232 connection to an auxiliary terminal or device for remote viewing.
Blooming — A situation in which too many photons are being produced to be received by a pixel. The
pixel overflows and causes the photons to go to adjacent pixels. Blooming is similar to overexposure in
film photography, except that in digital imaging, the result is a number of vertical and/or horizontal
streaks appearing from the light source in the picture.
Baud Rate — The number of discrete signal events per second; bits per second.
Capture — The act of acquiring and storing video images in an imager or host computer. Also, the
image captured.
Charge-Coupled Device (CCD) — A semiconductor device with an array of light-sensitive elements
that converts light images into electrical signals.
Check Character — A Modulus 43 or Modulus 10 character that is added to encoded symbol data for
additional data integrity.
Complementary Metal Oxide Semiconductor (CMOS) — Like CCDs, CMOS imagers include an
array of photo-sensitive diodes, one diode within each pixel. Unlike CCDs, however, each pixel in a
CMOS imager has its own individual amplifier integrated inside.
Connector — A plug or socket on a device or cable providing in/out connectivity for various circuits and pins.
Concentrator — Intermediary device that relays data from imagers to a host and commands from the
host to the imagers or other devices.
Counter — Memory space allocated to keep track of imager events.
Daisy Chain — Linkage of primary and secondary imagers allowing data to be relayed up to the host
via auxiliary port connections.