Microscan MS-3000 User Manual page 122

Appendices
Relay Driver. A TTL signal sent by the decoder. The output is determined
by the relay driver selection during configuration.
Round Spot. The standard laser beam as it appears on the label being
scanned, sometimes slightly ovalized.
Scanner. A scanning device which is comprised of a scan head and a
decoder integrated in one package.
Scan Head. The module that projects laser light on bar code labels and
receives reflected light back. This device changes the analog signal to a
digital representation of the bar code and outputs it to a decoder.
Scan Width. The measurement (inches or centimeters) of the scan beam
line at the readable scan range of a given application.
Serial Commands. On-line data strings (including configuration and opera-
tions) from a host or other terminal to the decoder, which are always pre-
ceded by a < left angle bracket symbol (unless redefined by Command
Start Character command) and followed by a > right angle bracket symbol.
Skew. Label (or scan head) rotation around the center of the skew axis.
Specular Reflection. The direct, mirror-like reflection of laser light back to
the scan head, causing over-light saturation.
Symbology. A set of bar code symbols, such as Code 39 or Code 128,
which have special rules to define the widths and positions of bars and
spaces to represent specific numeric or alphanumeric information.
Tilt. Label (or scan head) rotation around the centerline of the scan beam.
Timeout. A user-selected period of time that ends a decoder's read cycle.
Trigger. A signal, either external or serial, that initiates the read cycle and
causes the decoder to expect label input.
TTL. Abbreviation for transistor-transistor logic, the standard for signal out-
put.
Wide-to-narrow Ratio. The ratio of the width of the widest (or wider) bar to
the narrowest bar of a given bar code symbology. For example, 2:1, 2.5:1,
3:1, and 4:1.
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MS-3000 Single Head Decoder User's Manual