Sony VPH-G90E, Service Manual

Page: 82 / 546

1-72
VPH-G90E/G90U/G90M
82
Adjustments
Adjustments
Adjusting the Lens Focus and Scheimpflug
3
Press the CUT OFF R and B keys to display the green signal only.
4
Open the upper cover.
For opening the cover, see page 18.
5
Adjust the center-focus.
Loosen the G1 screw, slide it so that the letters H at the center of the
screen are in focus, and then tighten the screw.
6
Adjust the corner-focus.
Loosen the G2 screw, slide it so that the letters H at all four corners of
the screen (white areas illustrated below) are in focus, and then tighten
the screw.
Repeat steps
5 and 6 until the green focus adjustment is completed.
(If the corner-focus cannot be adjusted completely, adjust it again after
finishing the Scheimpflug adjustment of the green lens.)
H H H H H H H H H H H H H H H H
H H H H H H H H H H H H H H H H
H H H H H H H H H H H H H H H H
H H H H H H H H H H H H H H H H
H H H H H H H H H H H H H H H H
H H H H H H H H H H H H H H H H
H H H H H H H H H H H H H H H H
H H H H H H H H H H H H H H H H
H H H H H H H H H H H H H H H H
H H H H H H H H H H H H H H H H
H H H H H H H H H H H H H H H H
H H H H H H H H H H H H H H H H
H H H H H H H H H H H H H H H H
H H H H H H H H H H H H H H H H
H H H H H H H H H H H H H H H H
H H H H H H H H H H H H H H H H
Hint for the lens focus adjustment
The letter “H” is made up of dots. Adjust the focus so that dots of the letter
“H” can be clearly seen as illustrated below.
Placing a white paper over the front of the screen will make it easier to see
the dots.
G1 screw R1 screw B1 screw
B2 screw G2 screw R2 screw
Adjustments
83
Adjustments
H screw
V screw
2
Adjusting the green magnetic focus and AQP/DQP roughly, if necessary.
The magnetic focus and AQP/DQP will be adjusted precisely after the lens
focus and scheimpflug adjustments. Adjust the green magnetic focus and
AQP/DQP roughly at this stage to make the later adjustments easily.
For details of the magnetic focus and AQP/DQP adjustments, see page 87.
3
Adjusting the green scheimpflug
After adjusting the green lens focus, adjust the green scheimpflug (angle of
the green CRT) so that the upper and lower parts, and the left and right
parts of the screen are equally in focus.
1
Open the upper cover.
For how to open the upper cover, see page 18.
2
Place a white paper over the front of the screen. Note whether the focal
planes on the upper, lower, left and right parts of the screen appear to
be leaning forward or backward.
H H H H H H H H H H H H H H H H
H H H H H H H H H H H H H H H H
H H H H H H H H H H H H H H H H
H H H H H H H H H H H H H H H H
H H H H H H H H H H H H H H H H
H H H H H H H H H H H H H H H H
H H H H H H H H H H H H H H H H
H H H H H H H H H H H H H H H H
H H H H H H H H H H H H H H H H
H H H H H H H H H H H H H H H H
H H H H H H H H H H H H H H H H
H H H H H H H H H H H H H H H H
H H H H H H H H H H H H H H H H
H H H H H H H H H H H H H H H H
H H H H H H H H H H H H H H H H
H H H H H H H H H H H H H H H H
3
Adjust the focus on the upper and lower parts with the V screw on the
green CRT using the supplied tool.
The supplied tool can rotate the screw in one direction only. To rotate
the screw in the reverse direction, turn the tool upside down.
Caution
Do not turn the tool forcibly when the screw has fully rotated. Otherwise,
the tool may slip out and injure your hand.
(continued)