Nokia 920C Service Manual page 10

4-2 Display Control Adjustments
4-2-1 Centering
Centering means to position the center point of
the display in the middle of the display area.
Horizontal size and position and vertical size and
position control the centering of the display.
Adjust the horizontal size and vertical size to their
optimal settings: 355 mm (H) x 266 mm (V)/920C.
310 mm x 232 mm/720C. 1280 x 1024 mode (91kHz/85Hz)
Adjust the horizontal position and vertical
position to ² 4.0 mm of the center point of the
screen.
|A-B| ² 4.0 mm. |C-D| ² 4.0 mm.
C
A
D
Figure 4-3. Centering
4-2-1 (a) HORIZONTAL SIZE ADJUSTMENT
CONDITIONS
Scanning frequency:
Display image:
Brightness:
Contrast:
Click on the << or >> box next to H_SIZE to
adjust the horizontal size of the display pattern to
355 mm. (Tolerance: ± 3 mm.)
4-2-1 (b) VERTICAL SIZE ADJUSTMENT
CONDITIONS
Scanning frequency:
Display image:
Brightness:
Contrast:
Click on the << or >> box next to V_SIZE to
adjust the vertical size of the display pattern to
266 mm. (Tolerance: ± 3 mm.)
4-2-1 (c) HORIZONTAL POSITION ADJUSTMENT
CONDITIONS
Scanning frequency:
Display image:
Brightness:
Contrast:
Click on the << or >> box next to H_POSI to
center the horizontal image on the raster.
720C/920C
DISPLAY AREA
B
EDGE OF BEZEL
91 kHz/85 Hz
Crosshatch pattern
Cut-off
Maximum
91 kHz/85 Hz
Crosshatch pattern
Cut-off
Maximum
91 kHz/85 Hz
Crosshatch pattern
Cut-off
Maximum
4-2-1 (d) VERTICAL POSITION ADJUSTMENT
CONDITIONS
Scanning frequency:
Display image:
Brightness:
Contrast:
Click on the << or >> box next to V_POSI to
center the vertical image on the raster.
4-2-2 Linearity
Linearity affects the symmetry of images as they
appear on the screen. Unless each row or column
of blocks in a crosshatch pattern is of equal size,
or within the tolerances shown in Tables 4-1 and
4-2, an image appears distorted, elongated or
squashed.
Table 4-1. Factory Preset Modes Linearity
Each block (10 %)
Horizontal: 20.9~23.1
4 : 3
Vertical : 20.9~23.1
Table 4-2. Other Modes Linearity: VGA, SVGA, XGA,
MAC, etc.
Each block (14 %)
Horizontal: 20.5~23.5
4 : 3
Vertical : 20.5~23.5
4-2-2 (a) HORIZONTAL LINEARITY ADJUSTMENT
CONDITIONS
Scanning frequency:
Display image:
Brightness:
Contrast:
To adjust the Horizontal Linearity, refer to Tables
4-1 and 4-2 for the tolerance range.
Click on the << or >> box next to H_LIN to
optimize the image.
4 Alignment and Adjustments
91 kHz/85 Hz
Crosshatch pattern
Cut-off
Maximum
Standard Modes Linearity
Difference between
adjacent blocks (4 %)
Horizontal: Less than 0.88 mm
Vertical : Less than 0.88 mm
Supported Timing Mode
Difference between
adjacent blocks (5 %)
Horizontal: Less than 1.10 mm
Vertical : Less than 1.10 mm
91 kHz/85 Hz
Crosshatch pattern
Cut-off
Maximum
4-3