Acer AM501, Service Manual

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18
4.10.7 Geometric Distortion By Luminance
The test pattern is composed of two white areas and a black area, the three areas are equivalents. The
input signal level is 700 mV with brightness control at cut-off and contrast control at maximum(see
Figure 12).
The distortion introduced by dynamic High Voltage variation, due to different brightness level on the
screen, are admitted with following limits:
|AC - BD| or |A'C'-B' D'|
≦
2.0mm
Figure 12
4.10.8 Linearity
The linearity of an image displayed on the CRT must meet the following requirements, with reference to
figure 13 for both X and Y axis.
The measured value of linearity shall be less than 6% when calculated using all lattices and shall be less
than 4% when calculated using adjacent lattices.
X1 X2 X3 X4 X5 X6 X7 X8
Y1
Y2
Y3
Y4
Y5
Y6
Y7
Y8
Figure 13:Linearity
Where: X max and X min are belong to the set Xi,i=1......8
X max, X min, be Calculated Same Line
Y max, Y min, be Calculated Same Row
Y max and Y min are belong to the set Yi,i=1....8
min max
min max
min max
min max
Y Y
Y Y
OR
X X
X X
+
−
+
−