Hand Held Products Quick Check Bar Code Verifiers 800, Руководство пользователя

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Quick Check® 600/800 Series User’s Guide 4 - 1
4
Reviewing Scan Data
Reviewing Scan Results
After you customize the verifier settings for your use, you are ready to scan bar
code symbols. The verifier acquires and analyzes data using the ScanProfile
Methodology specified in ISO/IEC’s
Bar Code Print Quality Guideline (ANS X3,
182). After a scan, the audio signal and the LEDs provide auditory and visual
information about the symbol. The verifier provides results using either
traditional print quality parameters to make a pass/fail judgement about the
symbol or the ISO/IEC methods to judge a symbol and report an ISO/IEC scan
grade. You can also review specific traditional or ISO/IEC parameters
(dimensional, reflectance and format parameters). Each parameter is described
later in this section. The flow chart in
Chapter 10, Flow Charts displays all the
scan data you can review and how to access each item using the menus.
Scan Grades
The scan grade is also known as the “Scan Profile Grade.” You can think of the
scan grade as the grade resulting from a single scan across the symbol, for
example, at exactly three millimeters from the top of the symbol. The scan grade
is the lowest grade received by one of the following parameters after a specified
number of scans (you specify the number of scans using the Extended Accuracy
setting):
• Edge determination
• Rmin/Rmax
• Symbol contrast
• Minimum edge contrast
• Modulation
• Decodability
• Defects
The scan grade must also comply with any additional requirements imposed by
the appropriate industry application standard, symbology specification or both for
each scan. For example, if you set the passing option test criteria to traditional,
the scan grade is a pass/fail judgement. However, if you set the passing option
to ISO/IEC, the scan grade is a letter or number grade.
Using the Extended Accuracy mode greatly reduces reading variability due to
variations in scanning motion and minor scan path variations. The Extended
Accuracy settings you can specify to calculate the scan grade include off (1), 2
through 10, 12, 15, 20, 30, 50 and 100.