Sony DVP-NS300 Training Manual page 6

Disc Warp Correction
Because of the finer DVD pitch, the laser must be perpendicular to the disc for maximum RF output from the
optical block. Figure 1-3 illustrates the differences between old servo tilt mechanism system (A) and the new
DTC system (B) that keeps the laser beam perpendicular. In earlier generations, a tilt servo (A) adjusted the
angle of the laser platform to keep the monitored RF level at peak. This system is complex and the platform can
"bottom out", limiting its range.
A TILT SERVO WARP
DISC COMPENSATION
B DTC WARP
DISC COMPENSATION
DISC
MOTOR
DISC
WHOLE
ASSEMBLY
ROTATES
FROM
HORIZONTAL
DISC
DISC
FIGURE 1-3 - TILT SERVO (A) VS. DTC (B)
LENS
PIVOT
LENS
PIVOT
LENS
OPTICAL
ASSEMBLY
LENS
OPTICAL
ASSEMBLY
4
WHOLE
ASSEMBLY
PIVOTS UP
ROTATES
FROM
HORIZONTAL
PIVOTS
DOWN
(LIMITED RANGE)
ILLUSTRATES
ROTATION OF
LENS
ONLY
ASSEMBLY REMAINS
HORIZONTAL
ILLUSTRATES
ROTATION OF
LENS
ONLY
ASSEMBLY REMAINS
HORIZONTAL
GGW5 1545
1. What's New?
4/9/03