Tektronix PHASER 380, Service Manual

Page: 131 / 346

Service Manual 5-29
Theory of Operation
5
Double scan image deposition. B-size or wide-format images are placed on the
drum using two scans the printhead separated by a long non-deposition skip
move. The image is laid down on the drum in the same manner as a single scan
image using 4-jet interlacing, except the image is divided into two halves. Jets
columns 18 through 88 deposited the right-half scan on the drum. Jets columns
1 through 71 deposit the left-half scan. Jet 18 through 20 of the right-side scan
interleave with jet columns 69 through 71 of the left-side scan to seamlessly join
the two halves together. This area of interleaving between the two images is
sometimes referred to as the “stitch.”
Figure 5-17 Printing the double scan pre-transfer image on the drum
Jet 69
Jet 70
Jet 71
Jet 18
Interleave or “stitch”
of the two image
depositions
9661-86
Jet 19
Jet 20
112 pixel-wide
field traveled by a jet
Left half scan
Right half scan
28 pixel
separation
between jets
2 Step
2 Step
1 Step