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1D Barcode Required Resolution

I am thinking about using NI VisionBuilder with mutiple GigE cameras to read UPC-A barcodes at a 100% scale factor, for which the minimum bar width would be 13mil, or about 0.33 mm.

Using the VisionBuilder 1D barcode tool, what is the required resolution to be able to reliably read these codes.

 

I would guess that to be conservative, I would want for the minimum bars to be at least 2 pixels wide (Niquist), but I notice that Cognex sells barcode scanners with a 1DMax algorithm that claim to operate successfully at 1 pixel per bar.

 

This is an important $$$ issue because of the large field of view, possibly requiring mutiple high-resolution cameras and lenses. 

 

Thanks!

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Hi Nelson,

 

If you haven't seen it already, this is an excellent guide to determining the minimum resolution and focal length you will need for an imaging application. To be on the safe side, I would recommend 3 pixels for the smallest feature. Once you have this information, you can look at some of the cameras we sell to find one with a resolution just higher than the minimum you calculated using the first article. After you have a camera picked out, you can use this tool to find lenses for the camera in the needed focal length.

 

Kind Regards,

 

Andrew T.
"His job is to shed light, and not to master" - Robert Hunter
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