Sharp LC-20B2UA, Service Manual

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15
LC-20B2UA
Test patterns in adjustment process mode
[1] IC801 (Video decoder) test patterns
1-1. Getting the test patterns displayed
Put the screen in AV1, AV2 or COMPONENT but keep out any signal. Call the adjustment process mode,
select “TEST PATTERN” in the 3rd line of page 7, make the settings 1 thru 6, and the following test patterns
show up.
1-2. Test patterns
}
Setting 1
}
Setting 2
Finer vertical stripes than Setting 1 are displayed.
}
Setting 3
}
Setting 4
A rather dark green-only pattern is displayed.
}
Setting 5
A half-tone green-only pattern is displayed.
}
Setting 6
A rather bright green-only pattern is displayed.
[2] IC1201 (LCD controller) test pattern
2-1. Getting the test pattern displayed
Put the screen in AV1, AV2 or COMPONENT but keep out any signal. Call the adjustment process mode,
select “G/A TEST PATTERN” in the 13th line of page 16, turn on the setting, and the following test pattern
shows up.
2-2. Test pattern
The following test pattern appears.
Note: When the IC801 and IC1201 test pattern display commands are both turned on at the same time, the IC1201
test pattern is given priority.
green green Y
ellow
Y
ellow
Cyan Cyan Magenta Magenta Green Green Red Blue
The color bars are displayed as shown at left.
Bright
Bright
Bright
Bright
Dark Dark
Dark
Dark
Dark
Dark
Dark
Dark
Green
Red
Blue
Black
0-level
gradation
White
63-level
gradation
W
h
i
t
e
Gray
16-level
gradation
Gray
32-level
gradation
Gray
48-level
gradation
Gray scale
Bright Bright Dark
Green
The green pattern is displayed as shown at left.