Wasp Bar Code WLS 8400 FZ Omnidirectional, Optical Throw, Orientation, Overhead, Percent Decode

Glossary GL-11

Omnidirectional	Bar codes read in any orientation relative to the
	scanner.
Optical Throw	The distance from the scanner face to the closest
	point at which symbol can be read; also, optical throw
	is the difference between range and depth of field.
Orientation	The alignment of the symbol's scan path. Two
	possible orientations are horizontal with vertical bars
	and spaces (picket fence) and vertical with horizontal
	bars and spaces (ladder).
Overhead	The fixed number of characters required for start,
	stop and checking in a given symbol. For example, a
	symbol requiring a start, stop and 2 check characters
	contains 4 characters of overhead.
Parameter	A variable that can have different values assigned to
	it.
PDF417	An error correcting 2-dimensional multi-row symbol
	developed in 1992 by Symbol Technologies, PDF417
	symbols are constructed from 4 bars and 4 spaces
	over 17 modules. The symbol size is from 3 to 90
	rows. There is no specified minimum or maximum
	for X or Y dimension. With at least the recommended
	minimum level of error correction, the recommended
	Y dimension is 3X. With less than the minimum
	recommended level of error correction, the
	recommended Y dimension is 4X. A quiet zone of 2X
	is specified on each side of a symbol. Because of
	delta decode techniques, the symbology is immune
	from uniform bar width growth. PDF417 supports
	cross-row scanning. The intellectual property rights
	associated with PDF417 have been committed to the
	public domain.
Percent Decode	The average probability that a single scan of a bar
	code would result in a successful decode. In a well-
	designed bar code scanning system, that probability
	should approach near 100%.
Pitch	Rotation of a bar code symbol in an axis parallel to
	the direction of the bars.
Plessey Code	A pulse-width, modulated bar code commonly used
	for shelf marking in grocery stores.