Epson Stylus Pro 4400 - Paper Left;Right Edge Detection During Printing; Paper Width Detection Timing

EPSON Stylus Pro 4400/4450/4800/4880/4880C Revision C
Operating Principles Printer Mechanism Components 147
PAPER WIDTH DETECTION
When paper is fed, the paper and platen are scanned and the change points of
the detected reflective light levels (paper present level <=> paper absent level)
are confirmed as the paper edges. The diagrams below show scan/detection
timing.
Figure 2-52. Paper Width Detection Timing
PAPER LEFT/RIGHT EDGE DETECTION DURING PRINTING
This is performed during borderless printing. For borderless printing of the
conventional printers, the data have been enlarged so that the data would run
out of the left/right edges by 3mm in printing. This printer detects the paper
edges with every pass, and by making immediate adjustments, the amount
forced out is reduced to 1.1mm from the paper edge and the quantity of
scattered ink is reduced. By executing every pass detection, printing can be
performed while following skew of the paper when the paper has skewed
(within the manufacturer's permitted range for skew), and the amount forced
out is maintained at a fixed level. However, in order to prevent forcing out from
absorption materials used for borderless printing, the printing is performed by
maintaining a fixed quantity for one side.
Figure 2-53. Paper Left/Right Edge Detection During Printing
2nd job
1st job
At paper set
At printing complete
At paper feed
ASF
Borderless Print
ON
ASF
Borderless Print
OFF
Roll Paper
Borderless Print
ON/OFF
Manual insertion
1.1mm 1.1mm
Absorption Material