RJS Inspector D4000 Auto Optic (FIRMWARE version A.05 and Earlier) - Manual (Page 70)

Operator
’
s Guide Appendix K
002-5564 RJS, Minneapolis, MN 63
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 contrast is the Reflectance difference
between adjoining bars and spaces. The minimum edge contrast is the smallest value of
EC = Rspace - Rbar 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 threshold, 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 intersects the midpoint between the space
reflectance (Rspace) and bar reflectance (Rbar) of adjoining elements. Visual measuring
techniques will generally locate the element edge closer to the center of the bar.
Element Reflectance Nonuniformity (ERN)
The reflectance difference between the highest peak and lowest valley within each
individual element and quiet zone. When an element consists of a single peak or valley,
its element reflectance non-uniformity is zero.