Oki LP-1040 Maintenance Manual page 641

(2) Subscanning direction grid chart's center: Four positions
<Items to Check>
Image at sensor connection parts, on the center of the original
<Check and Criteria>
Check that the horizontal lines are not disconnected at the sensor connection part.
Areas on the original marked by the ▲ symbol are guides designating CIS sensor
connections. When horizontal lines at connections are not disconnected, the results are
OK.
Chapter 11 Scanner Calibration
11-43