Pioneer AVIC-Z2/XU/UC Service Manual page 298

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1.2.4 Focus jump
Focus jump is used for single-sided, double-layered or double-sided, double-layered discs. The layer closest to the
objective lens is called layer 0 (L0), and the other layer is layer 1 (L1).
L 1
( L a y e r 1 )
L 0
( L a y e r 0)
The waveforms in the focus jump mode are shown below:
Focus jump waveform
L0→L1
TE
FD
The focus-jump operation flow is described below:
1. The tracking loop is unlocked on the layer that is being played.
2. A jump command is issued to jump to the targeted layer.
3. The tracking loop closes on the targeted layer and reproduction starts.
The detailed processes after a jump command is issued are as follows:
1. The pickup lens is accelerated towards the target layer until the FE signal detects the focus jump acceleration
completion level. If the acceleration timeout occurs before the acceleration completion level is detected, the
acceleration is forcibly terminated.
2. No drive voltage is applied until the FE signal detects the deceleration starting level, and the lens is kept moving by
the inertia.
3. With the deceleration starting level detected, the lens starts decelerating, and continues it until the deceleration
completion level is detected. If the deceleration timeout occurs before the deceleration completion level is detected,
the deceleration is forcibly terminated.
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6
L 0 L 1
L 1
L 0
O b j e c t i v e l e n s
L1→L0
C X - 3 01 6
6
7
L 1 L 0
B C
A D
7
8
A
B
C
D
E
F
9
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