- 32 -
If this gradual dimming is not completely uniform then a factory
recalibration would be required to re-establish the situation of creating
uniform scan reflectance profiles from the scanning heads.
If a uniform profile is not being achieved then a barcode symbol may start
to achieve lower grades, particularly for modulation, than it should be
getting. However, this may not always be obvious to the user when simply
trying to verify barcodes symbols.