space reflectance (Rs): The largest reflectance value in a space or quiet zone.
speck: See “spot”.
spectral response: The sensitivity of a scanner or other device to light of
different wavelengths.
specular reflection: Reflection from a surface in which the angle of reflection to
normal equals the angle of incidence to normal. Specular reflection from a
surface perpendicular to the scanner may “blind” the scanner. Compare to
“diffuse reflection.”
spot: (1) An ink or dirt mark or other area of low reflectance in an area of a
symbol that is intended to be of high reflectance. (2) The area illuminated by
either a laser scanner or light pen. See “void.”
SSCC: The 18-digit structure used within the UCC and EAN systems that serves
as the unique package identifier for transport units, formerly known as the Serial
Shipping Container Code or SSCC-18.
start character; start pattern: A pattern that indicates the beginning (left hand
side) of a machine-readable symbol.
stop character; stop pattern: A pattern that indicates the end (right hand side)
of a machine-readable symbol.
substitution error: The situation where the reading process extracts the wrong
symbol character from the printed image. Compare to “misread,” “non-read.”
substrate: The material or medium upon which printed matter (such as a
machine-readable symbol or a coating) is imposed.
supplier: In a transaction, the party that produces, provides, or furnishes an
item or service. Compare to “customer”.
symbol: A combination of bar code or two-dimensional symbol characters
including start/stop characters, quiet zones, data characters, special function,
and error detection and/or correction characters required by a particular
symbology, that forms a complete, scannable entity.
symbol aspect ratio: See “aspect ratio.”
symbol character: The physical representation of the codeword as a pattern of
dark and light elements. There may be no direct one-to-one mapping between
symbol character and data character or auxiliary character. Decoding through
the compaction rules may be necessary to identify the data. Symbol characters
may have a unique associated symbol character value.
symbol check character: A symbol character calculated from the other symbol
characters in a machine-readable symbol in accordance with an algorithm
defined in the symbology specification and used to check that the machine-
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