| 摘要 |
PURPOSE:To detect paper face correctly regardless of longitudinal or lateral shift thereof by projecting light from each light emitting element onto a print face then receiving the reflected light through each light receiving element and converting the information on the print face into an electrical amount thus monitoring the print face. CONSTITUTION:A square sensor 1 comprises a group of light emitting elements and a group of light receiving elements 4 arranged on a substrate 2. A plurality of light receiving elements R00, R01... are arranged in matrix and a plurality of light emitting elements 6, 6a are arranged around the group of light receiving elements 3. Light emitted from each light emitting element is projected onto a print face 5 to be measured then the reflected light is received by a light receiving element, e.g. R08, and converted into an electrical amount thus monitoring the print face. Such a print face monitoring sensor 1 can monitor a print matter over a relatively large face and can monitor the print face even if it is shifted from a predetermined position. By such arrangement, the print face can be monitored reliably and gathering work can be improved. |
