Dell 1907FPf - Page 34

Service Manual
33
Item
Content
Equipment
Test OSD
function
1.Signal is set as 1280×1024@60Hz under General-1
2. LCM button are from left to right, checking whether each
single function key and compound function key can be worked.
Chroma
Signal Generator
Contrast Check 1. Set input mode to 1280×1024@60Hz
2. Set to 32gray scale pattern
3. Set contrast to the maximum. At most 6 bars cannot be
distinguished.
4. At default setting (B=75%, C=50%), No bar over saturation.
Chroma
Signal Generator
Color
Temperature
1. Do “Auto color Balance” at 1280×1024@60Hz, White
and black pattern
2. Measure color temperature, check if it complies with the
following temperature :
Normal Preset(sRGB)
03
.
0
329
.
0
,
03
.
0
313
.
0
±
=
±
=
y
x
Blue Preset
03
.
0
297
.
0
,
03
.
0
283
.
0
±
=
±
=
y
x
Red Preset
03
.
0
344
.
0
,
03
.
0
328
.
0
±
=
±
=
y
x
u x, y 範圍設限於 ± 0.02
u R, G, B Min.設限分別為 240, 245, 220
Chroma Signal
Generator and color
analyzer
CCT
(Correlated
Colour
Temperature)
Variation
1. Do “Auto color Balance” at 1280×1024@60Hz, White and black
pattern
2. Background Colour: RGB 204, 204, 204
3. The measurement position “Pc” shall be a 40mm x 40mm square
positioned in the centre of the screen (RGB settings: 255, 255, 255)
4.
22
)''()''(''
mCCTmCCT
vvuuvu −+−=∆
CCT in K
CCT
u'
CCT
v'
9300 (Blue) 0.1888 0.4457
6500 (Normal) 0.1978 0.4684
5700 (Red) 0.2028 0.4781
5.
m
u' and
m
v' : measured values of the screen for the preset CCT
CCT
u' and
CCT
v' : CIE reference chromaticity co-ordinates
6. 01.0''
≤
∆
vu
v If the TCO’03 set is not complied with 6500K, adjust B color (Min.為
240); otherwise, return as TCO’99 set.
Adjust it if not complied with either 9300K or 5700K.
Modes switching
check
1. Use Chroma Pattern Generator to make sequence.
VESA (640x480 800x600 1024x768 1152x864 1280x1024),
the detail supported modes (see table 1) and power saving
signal.
2. Confirm the above timing modes must be full screen and
the picture must be normal.
3. LED is amber at power saving mode.
Chroma
Signal Generator
VGA cable
detector
When VGA cable is not plugged out, self-test OSD will be
floated.
Visual check
Y measurement
at default setting
1. Set brightness and contrast to default value 75 at 6500K
2. With full white pattern, Y shall be 230
±
20 cd/m
2
3. Brightness 100%, contrast 100%, Full white pattern, User Mode, R,G,B
to 100%, Y should be over 250nits.
Chroma Signal
Generator and Color
Analyzer
OSD Lock Test Soft Lock: When OSD is locked, this icon should appear for only 2 seconds
with all buttons pressed, except for the “Menu” and “Power” ones.
Hard Lock: Press “Menu” button for 15 seconds enables the “locked” icon
to be displayed, which will lock A ll buttons expect for the “Power”. Press
“Menu” button for another 15 seconds enables the “unlock” icon to be
shown.
Visual Inspection