5-9
IM AQ1200-01EN
W
aveform Display
3
2
1
4
5
6
7
8
9
10
11
12
13
14
15
16
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18
Index
App
Ghost Cursors
Ghost cursors are used to check for secondary reflections. A secondary reflection is a reflection that is
detected in a location where no event actually occurs.
Off: Ghost cursors are not displayed.
On: Ghost cursors are displayed.
Ghost cursor
Turn the rotary knob to move to the next secondary reflection detection point.
Secondary reflection
How Secondary Reflections Are Generated
The optical pulse that is generated from position I in the following figure propagates in the direction
of II.
↓
Light ray A that is reflected at connection II is reflected again at connection I and propagates in the
direction of II as light ray B.
At this point, the AQ1200 detects A as an event.
↓
B is again reflected by connection II, and this generates reflected light ray C. At this point, the
AQ1200 detects C as an event.
Because the AQ1200 measures all the reflected light rays, A, C, and D, C is also detected as an
event in the same manner that an actually generated reflection is. Therefore, while there is no
actual event in this location, it appears as if an event has in fact occurred.
Distance 2L
Distance L
Optical fiber cable connection
I
II
III
A
B
A
C
D
C
D
5.5 Setting the Waveform Information Display
