Pixel Defects On Screens - Medion AKOYA P54037 Mode D'emploi

12. Pixel defects on screens

For active matrix TFTs with a resolution of 1600 x 900 pixels, each of which
consist of three sub-pixels (red, green, blue), there are a total of approx. 4,3
million control transistors in use. Due to this very high number of transistors
and the associated extremely complex manufacturing processes used, occa-
sionally one or more pixels can fail or become incorrectly controlled.
In the past, there were a number of approaches for defining the permitted
number of pixel defects. However, these approaches were mostly very compli-
cated and varied from one manufacturer to the next. When handling warran-
ty issues for all of its display products, MEDION therefore adheres to the strict
and transparent requirements of the standard ISO 9241-307, Class II; which
has been briefly summarised below.
The ISO standard ISO 9241-307 defines, amongst other things, the generally applicable guidelines relating to pixel de-
fects. Pixel defects are categorised into four fault classes and three defect types. Every individual pixel consists of three
sub-pixels, each of which is assigned a basic colour (red, green, blue).
Pixel fault class
0
I
II
III
IV
n* = 1,5
The table describes the maximum number of pixel failures allowed on the screen, before a warranty claim arises. A war-
ranty claim may be applicable if the above number of defects in a category is exceeded.
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Defect type 1
Continuously lit pixel
0
1
2
5
50
Sub-Pixel
Defect type 2 Defect type 3
Continuously black Defect sub-pixel
pixel
lit
0
1
2
15
150
5 Pixel
Rows
Pixel
blue
green
red
black
0 0
2 1
1 3
0 5
5 0
5-n* 2xn*
0 10
50 0
50-n* 2xn*
0 100
500 0
500-n* 2xn*
0 1000