RJS Inspector D4000 SP (FIRMWARE version A.06 and Later) User Manual
Page 65
Operator
’s Guide
Appendix K
002-5572
RJS, Minneapolis, MN
57
Edge Contrast (EC) See Edge Contrast(min)
The difference between the space reflectance (Rs)
and adjoining bar reflectance (Rb).
EC = Rs - Rb
Edge Contrast (min)
This parameter grade can be
“A” or “F.” Edge co
n-
trast is the Reflectance difference between adjoin-
ing bars and spaces. The minimum edge contrast
is the smallest value of EC = R space
–
R bar
found in the scan.
The grade is determined by calculating the edge
contrast of every element in a symbol and then
comparing the lowest value to a fixed threshold in
the specification (15%).
If the value is equal to or greater than the thresh-
old, the grade is
“A.” If the value is less than the
threshold, the grade is
“F.”
Element
A generic term used to refer to either a bar or
space in a bar code symbol.
Element Edge
The location where the scan reflectance profile in-
tersects the midpoint between the space reflec-
tance (R space) and bar reflectance (R bar) of ad-
joining elements. Visual measuring techniques will
generally locate the element edge closer to the
center of the bar.