Apparatus for on-line defect zoning

An apparatus for obtaining sheet product from a web running at on-line speeds including inspection means for determining the existence and location of anomalies in said web and generating corresponding anomaly output signals, classifying means responsive to said anomaly output signals for classifying, by generating reject signals, preselected rectangular areas of said web as acceptable or rejectable, means for chopping said web into sheets of said preselected areas, and means responsive to said reject signals for segregating said unacceptable sheets from said acceptable sheets, the improvement wherein:

• said classifying means including logic means responsive to said anomaly output signals for generating region signals defining a closed region containing all of said anomalies in each said preselected area, and
• computer means for comparing said region signals with reference signals defining acceptable product to classify said preselected areas as acceptable or rejectable for optimizing the yield of sheet product.