Omron V440-F, Руководство пользователя

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4 Setup
4-4 V440-F C-Mount Code Reader User Manual
4-2 Train using Autocalibration
This section describes how to perform
Autocalibration
in the WebLink user interface.
The Autocalibration function is used to automatically determine the best combination of image acquisition
and image preprocessing parameters that will result in optimum decoder performance on a single difficult
to read symbol in the field of view.
The following settings are optimized during Autocalibration:
• Exposure
• Gain
• Morphology
• Morphology Size
• Binning
The calibration algorithm performs an exhaustive search for the optimum combination of the above
parameters that will result in the highest decode success rate, with the lowest decoding time variance
between successive read cycles. Decode speed is also optimized, but is secondary to high success
rate and low read time variance. Decode success and decode time repeatability are critical to real time
production line performance.
You must position the reader, and choose the best type of lighting to create the highest contrast image
possible, with the lowest amount of background noise.
Set the aperture of the C-Mount lens to F5.6 or F8 to ensure good depth of field. Use a lower F# if fast
exposure times are more important than Depth of Field. Focus the lens using live video mode so that
the code is in good focus.
Perform a Quick Photometry operation with the code in the center of the field of view.
4-2-1 Steps to Take Before Autocalibration
Ensure Adequate Resolution
You should choose the correct lens and reader standoff to ensure the adequate resolution for either 1D
or 2D code reading. Two pixels per thin bar on a 1D code, or 5 pixels per cell on a 2D code are
considered a good starting place. Refer to
2-2-1
,
Determining the Optical Setup
, to determine exact
resolution and optical setup for customer applications.
Optimize Lighting
Set Good Focus
Perform Quick Photometry