Canon F-1, Service Manual

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Technology > Controls > Reader > Original size detection
Technology > Controls > Reader > Original size detection
Following is the combination of detection result and original size.
A/B: Original presence/absence detection result of 2 points (Refer to [a. 2 point original
detection at each detection position].).
Y: Output level has no change (refer to [Detection operation]).
-: Output level has change (refer to [Detection operation]).
Original size
Scanner unit detection position
Original size sensor 1 1 2 3 4 5
A B A B A B A B A B
A3 Y Y Y Y Y Y Y Y Y Y Y
B4 Y Y Y Y Y Y Y Y - - Y
A4R Y Y Y Y Y Y - - - - Y
A4 Y Y Y Y Y Y Y Y Y Y -
B5 Y Y Y Y Y Y Y Y - - -
B5R Y Y Y Y - - - - - - Y
A5 Y Y Y Y Y Y - - - - -
B6 Y Y Y Y - - - - - - -
A5R Y Y - - - - - - - - -
None - - - - - - - - - - -
Original size
Scanner unit detection position
Original size sensor 2 1 2 3
A B A B A B
11” x 17” Y Y Y Y Y Y Y
LGL Y Y Y Y - - Y
LTRR Y Y Y Y - - -
LTR Y Y Y Y Y Y -
STMTR Y Y - - - - -
STMT Y Y Y Y - - -
Absent - - - - - - -
To keep the high accuracy detection even though an original moves when the DADF is
closed, this machine has 2 types of controls.
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a. 2 point original detection at each detection position
In main scanning direction, the machine determines whether the original is present or not
from the 2 points of reading sensor output near the original detection position.
Near 4 mm
Near 13 mm
1A: additional point
of detection
Original size
border line
Original size
border line
1B: conventional point
if detection
Result
Judgment
A B
Y Y Present
Y - Present
- Y Present
- - Absent
* Signal change with DADF Open to Close
Changed: -
Others: Y
The machine uses OR combinations of 2 points for identification.
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