Samsung DP15HS/HT Service Manual page 15

4-3-2 (d) WHITE BALANCE ADJUSTMENT VERIFICATION
CONDITIONS
Scanning frequency:
Display image:
X-Y Coordinates:
ABL Luminance
Brightness:
Contrast:
1. Check whether the color coordinates of the
back raster satisfy the above spec.
If they do not, return to 4-3-2 (a) and readjust
all settings.
2. Display a full white pattern.
3. Select ÒGeometryÓ in softjig menu.
4. Select Ò@7: 5-ft Ò in right menu.
5. Check whether the white coordinates of the
video meet the above coordinates spec.
6. Select Ò@8: 24-ft Ò in right menu.
7. Check whether the white coordinates of the
video satisfies the above spec.
If they do not, return to 4-3-2 (a) and readjust
all settings.
Select ÒColorÓ and click Ò@2: CHANNEL 2Ó
for color ajdustment for 6500K
Repeat the sequence of 9300K adjustment.
The luminance values the same as 9300K, but
the color coordinated of back raster and white
box are : x = 0.313 ± 0.02 y = 0.329 ± 0.02
4-3-3 Luminance Uniformity Check
Luminance is considered uniform only if the ratio
of lowest to highest brightness areas on the screen
is not less than 7.5:10.
CONDITIONS
Scanning frequency:
Display image:
Brightness:
Contrast:
DP15H*/DP17L*
68 kHz/85 Hz (17Ó)
54 kHz/85 Hz (15Ó)
Back raster pattern
Full White Pattern
x = 0.283 ± 0.02,
y = 0.298 ± 0.02
Refer to 4-3-2(c)
Maximum
5 ft-L, 24 ft-L
68 kHz/85 Hz (17Ó)
54 kHz/85 Hz (15Ó)
(1024 x 768)
White flat field
Cut off point at 24 ft-L
Maximum
PROCEDURE
Measure luminance at nine points on the display
screen (see figure below).
Figure 4-10. Luminance Uniformity Check Locations
4-3-4 Focus Adjustment
CONDITIONS
Scanning frequency:
Display image:
Brightness:
Contrast:
PROCEDURE
1. Adjust the Focus VR on the FBT to display the
sharpest image possible.
2. Use Locktite to seal the Focus VR in position.
4-3-5 Color Purity Adjustment
Color purity is the absence of undesired color.
Conspicuous mislanding (unexpected color in a
uniform field) within the display area shall not be
visible at a distance of 50 cm from the CRT
surface.
CONDITIONS
Orientation:
Scanning frequency:
Display image:
Luminance:
Note: Color purity adjustments should only be
attempted by qualified personnel.
4 Alignment and Adjustments
68 kHz/85 Hz (17Ó)
54 kHz/85 Hz (15Ó)
(1024 x 768)
ÒHÓ character pattern
Cut off point
Maximum
Monitor facing east
68 kHz/85 Hz (17Ó)
54 kHz/85 Hz (15Ó)
White flat field
Cut off point at the center
of the display area
4-7